Oncology News Neuro-oncology Supplement 2016 by Oncology News

Oncology news

Neuro-oncology Supplement 2016

The Oncology News Neuro-oncology supplement is brought to you by medac GmbH (UK)

ISSN 1751-4975

This Neuro-oncology supplement has been brought to you by medac GmbH UK Branch, Scion House, Stirling University Innovation Park, Stirling, FK9 4NF T: + 44 (0)1786 458086 • F: + 44 (0)1786 458032 • E : info@medac-uk.co.uk • www.medac-uk.co.uk

NEURO-ONCOLOGY SUPPLEMENT

ast year Oncology News released a special Supplementary British Neuro-oncology Society (BNOS) issue to coincide with the Society’s annual conference at Nottingham. This appeared to be well received and so, once again, a collection of articles from previous issues as well as a couple of new pieces have been brought together to accompany the very first BNOS conference to be held at Leeds. This year focuses on the development of research centres supported by Brain Tumour Research and the critical role of establishing such centres which bring together critical masses of dedicated brain tumour researchers to address some of the challenges which must be confronted in the quest for knowledge that will lead to clinical improvements for brain tumour patients. It also covers some of the diverse areas of research within the centres and also addresses the importance of nurse specialists in neuro-oncology, particularly in the context of patient survivorship. The regular articles in Oncology News serve a particular need in providing fundamental updates on research and clinical practise to a broad based audience without the complexity and detail of publications in standard scientific/medical journals. Oncology News is always seeking contributions to its Neuro-oncology section and I would be very pleased to receive short articles from BNOS members who feel that they have something of interest within their own particular field which would appeal to anyone in the brain tumour sector as well as to those nurses, clinicians, researchers and charity members who represent other areas of oncology.

Professor Geoffrey J Pilkington BSc PhD CBiol FSB FRCPath, Professor of Cellular and Molecular Neuro-oncology, Institute of Biomedical and Biomolecular Sciences, School of Pharmacy and Biomedical Sciences, University of Portsmouth, Portsmouth, UK E: geoff.pilkington@port.ac.uk

Professor Geoffrey Pilkington, Neuro-oncology Editor, Oncology News.

INSIDE 04 Brain Tumour Research reaches important milestone 06 The clinical and scientific team members at the new Imperial College Brain Tumour Research Centre of Excellence 08 Brain Tumour Research – the research centre model 10 New therapeutic approaches for the treatment of brain tumours 12 The therapeutic potential of targeting brain tumour metabolism through LDHA 16 Malignant Gliomas and long term survivorship – exploring the vital role of the Neuro-Oncology Specialist Nurse 19 Dysregulation of Histone Deacetylases in paediatric brain tumours

Oncology News is published by McDonnell Mackie, 88 Camderry Road, Dromore, Co Tyrone, BT78 3AT, N Ireland. Publisher: Patricia McDonnell Web: www.oncologynews.biz Advertising and Editorial Manager: Patricia McDonnell E: Patricia@oncologynews.biz T/F: +44 (0)288 289 7023 M: +44 (0)7833 185116 Printed by: Warners Midlands PLC, T: +44 (0)1778 391057 http://is.gd/oncologyfacebook

Copyright: All rights reserved; no part of this publication may be reproduced, stored in a retrieval system or transmitted in any form or by any means, electronic, mechanical, photocopying, recording or otherwise without either the prior written permission of the publisher or a license permitting restricted photocopying issued in the UK by the Copyright Licensing Authority. Disclaimer: The publisher, the authors and editors accept no responsibility for loss incurred by any person acting or refraining from action as a result of material in or omitted from this magazine. Any new methods and techniques described involving drug usage should be followed only in conjunction with drug manufacturers’ own published literature. This is an independent publication – none of those contributing are in any way supported or remunerated by any of the companies advertising in it, unless otherwise clearly stated. Comments expressed in editorial are those of the author(s) and are not necessarily endorsed by the editor, editorial board or publisher. The editor’s decision is final and no correspondence will be entered into.

Oncology News | Neuro-oncology supplement 2016 | © McDonnell Mackie

NEURO-ONCOLOGY SUPPLEMENT

Brain Tumour Research reaches important milestone

Neurosurgeon Kevin O'Neill who leads the new Brain Tumour Research Centre of Exellence.

he charity Brain Tumour Research has reached an important landmark with the opening of a new research centre in London. The launch of a ground-breaking partnership with Imperial College Healthcare NHS Trust (London) means the charity is more than half-way towards its aim of creating a network of seven dedicated research centres. Patients, carers, scientists, clinicians and charities from across the UK gathered at the Burlington Danes building adjacent to Hammersmith Hospital, for the official launch of the Centre of Excellence on 24th September. It joins centres at Queen Mary University of London, and at universities in Portsmouth and Plymouth, to become the fourth funded by Brain Tumour Research. The charity’s Chief Executive, Sue Farrington Smith, said: “This new centre brings a welcome and timely boost to long-term sustainable and continuous research into brain tumours. It is also a great milestone as it signifies we are more than half-way on our journey to create seven dedicated research centres. This number will ensure there is a critical mass of researchers who will bring us closer to a cure. With the assistance of our supporters and member charities, we will continue to work on behalf of the 16,000 people who are diagnosed with a brain tumour each year in order to fund the fight. “Brain tumours kill more children and adults under the age of 40 than any other cancer … yet just 1% of the national spend on cancer research is allocated to this devastating disease. This is unacceptable!” The new centre was chosen after a rigorous selection process including international peer review. While existing

centres are led by neuroscientists, Imperial College Healthcare NHS Trust’s is the first in the charity’s network to be headed up by a pioneering brain surgeon, Kevin O’Neill. Earlier this year Mr O’Neill, consultant neurosurgeon at Imperial College Healthcare NHS Trust’s Charing Cross Hospital, was part of a team who used an “intelligent” knife – or iKnife to diagnose abnormal tissue during an operation to remove a brain tumour. It was the first time it had been used in Europe. Mr O’Neill was consultant to John Fulcher who was lost to a glioblastoma multiforme (GBM) in June 2001 at the age of 52. John’s widow Wendy went on to set up the Brain Tumour Research Campaign (BTRC) and is now chairman of Brain Tumour Research. “John and I had been married for 16 years,” said Wendy, 63, from West London. “When John was ill and after his death I learnt how little was known about brain tumours and how little research funding was available. Brain tumour research was seriously under-funded and I was shocked to learn there was no national charity dedicated to this area. “There was nothing Kevin or I could do to save John but by launching my own charity and later becoming chair of trustees at Brain Tumour Research, I felt perhaps some good might come from bad – and it is helping Kevin and others who are able to tackle the terrible effects of the disease, and save others from the suffering that John and so many others have endured,” she said. Mr O’Neill said: “I continue to be astounded by the courage of patients and their families, none more so than in the case of Wendy who, in her grief, has found great depths of drive and determination

Oncology News | Neuro-oncology supplement 2016 | © McDonnell Mackie

NEURO-ONCOLOGY SUPPLEMENT

Wendy Fulcher with Kevin O’Neill placing a tile dedicated to her husband onto the “Wall of Hope’.

to ensure our work has a future. We must fight this disease until we have a cure and we remain committed to doing all we can to improve outcomes for our patients. “As a brain surgeon, it’s my job to go in and remove brain tumours, but I know all too well that this isn’t enough to remove the cancer. Working with a team of researchers, we are exploring novel treatments to halt brain tumour cell invasion into healthy brain tissue. “I am delighted to be working with Brain Tumour Research to help push forward scientific frontiers to bring us closer to a cure.” Among those who attended the event was author Marion Coutts, who read an extract from The Iceberg, which won The Wellcome Book Prize 2015 and is a memoir about the diagnosis, illness and death of her husband, the art critic Tom Lubbock who died of a brain tumour in January 2011. The research and fundraising partnership between Brain Tumour Research and the Trust aims to raise £1 million a year towards new studies involving clinicians at the Trust’s neurooncology unit at Charing Cross Hospital working with scientists from Imperial College London. The occasion also saw the unveiling of a new “Wall of Hope”. Each day of research costs £2,740 and is represented

Marion Coutts.

by unique tiles on the wall which are dedicated to patients, their families, friends and corporate supporters. The new centre is the second in London. Last year saw the opening of the Brain Tumour Research Centre of Excellence at Queen Mary University of London. Research here is focused on GBM and is led by Professor Silvia Marino, a leading brain tumour scientist and neuropathologist working within Queen Mary’s Blizard Institute. Also opened in 2014, the Brain Tumour Research Centre of Excellence at Plymouth University sits within the Peninsula Schools of Medicine and Dentistry. The team here, led by Professor Oliver Hanemann has a world-leading track record in researching low-grade brain tumours occurring in teenagers and adults. By identifying and understanding the mechanism that makes a cell become cancerous, the team explores ways in which to halt or reverse that mechanism. A key innovation is fast track: testing new drugs in human primary cell cultures leading to innovative phase 0 trials leading to adaptive phase II/III trials with the potential for making drug therapies available to patients both safely and faster. The charity’s first centre was established at the University of Portsmouth in 2009 and is now the largest dedicated brain

Oncology News | Neuro-oncology supplement 2016 | © McDonnell Mackie

tumour research centre in the UK under the leadership of Professor Geoff Pilkington. The centre has five research sub-groups which address different areas of brain tumour biology critical to the provision of knowledge which will underpin patient outcomes: childhood brain tumours, blood brain barrier (cancer metastasis and drug delivery), novel and re-purposed therapeutics, mitochondria and metabolism and tumour micro-environment. Fundraising in its own right, Brain Tumour Research is also an umbrella charity, working in collaboration with member charities around the UK. Together with this network and supported by the fundraising achievements of Umbrella Groups and fundraisers across the UK, some £4 million was raised in 2014 to fund both brain tumour research and to provide support for patients and families. The charity is striving to fund a network of seven dedicated research centres whilst challenging the government and larger cancer charities to invest more in brain tumour research.

To donate £5 to help the work of Brain Tumour Research, text RSCH01 £5 to 70070. www.braintumourresearch.org

NEURO-ONCOLOGY SUPPLEMENT

The clinical and scientific team members at the new Imperial College Brain Tumour Research Centre of Excellence Clinical

Mr Kevin O’Neill is Head of Neurosurgery and Honorary Senior Lecturer in the Division of Brain Sciences, Department of Medicine, Imperial College London and now directs the new Brain Tumour Research Centre of Excellence at Imperial College London. Kevin is a Consultant Neurosurgeon, Head of Neurosurgery and Trust lead for Neuro-oncology at Imperial College Healthcare NHS Trust specialising in neurosurgical oncology and complex neurovascular surgery. He also leads the Neuro-oncology research group at Imperial College and its various collaborations internally, nationally and internationally. Over and above his medical practice, he chairs the Board of Trustees for the Brain Tumour Research Campaign a founder member of the charity Brain Tumour Research. More generally he is the National Institute of Healthcare Research (NIHR) Specialty Lead for Cancer in The North West London Clinical Research Network and sits on the Clinical Pathway Group for Brain and CNS cancer for the London Cancer Alliance (LCA) integrated cancer network. During his early career in neurosurgery Kevin also experienced the value of a working brain tumour research lab by spending time in Prof. Geoff Pilkington’s laboratories at King’s College London where he was engaged in work on the cell adhesion molecule receptor, CD44 in glioma. This appreciation of lab science has led to the development of a team of world-class researchers to investigate the biology of tumour metabolisms to further

understand the behaviour of this disease. Moreover, the clinical team will also be able to extend their use of innovative 3D real time surgical imaging. Earlier this year and along with Mr Babar Vaqas, he used Raman Spectroscopy to diagnose abnormal tissue during an operation to remove a brain tumour; the first time such technology had been used in Europe.

From a scientific perspective, he is interested in the application of novel scientific and computational techniques to clinical problems. These include novel techniques for systemic reviews and evidence aggregation as well as mathematical modelling of prognosis in patients receiving palliative chemotherapy. Matt works mainly at Charing Cross Hospital, with an excellent multidisciplinary team of surgeons, radiologists, nurses, oncologists and others who provide diagnostic and treatment services across, and beyond, north-west London. The most recent National Cancer Intelligence Network data shows that the team have the best brain tumour survival in the country.

Scientific Research Dr Matt Williams is Consultant Clinical Oncologist and Honorary Clinical Senior Lecturer at Imperial. Matt has a clinical and research interest in brain and central nervous system tumours. Clinically, he delivers radiotherapy and chemotherapy to patients with brain and spinal tumours, including Intensity Modulated Radiation Therapy and stereotactic radiotherapy. His clinical research focuses on patterns of care and outcomes in patients with a wide range of tumours, and developing better ways of assessing patient outcomes.

The primary aim of the research team is to use genetic, epigenetic and metabolomic approaches to identify the key molecular events underpinning development of Glioblastoma Multiforme (GBM); the most aggressive and lethal primary brain tumour. Cancer is increasingly recognised as a disease underpinned by profound changes in cellular metabolism. This altered metabolism represents cancer’s achilles’ heel and our key questions are based around identifying and testing these

Oncology News | Neuro-oncology supplement 2016 | © McDonnell Mackie

NEURO-ONCOLOGY SUPPLEMENT

metabolic changes to determine if they would be novel therapeutic strategies for GBM. Moreover, since tumour hypoxia (low 02 levels) constitutes a major challenge to current cancer therapies, they are investigating gene regulation and expression under such physiologically relevant conditions. They envisage that their comprehensive approach will reveal cancer specific altered pathways and identify new therapeutic strategies for brain tumours.

Dr Nelofer Syed is Principle Investigator of the John Fulcher Molecular Neurooncology Laboratory at Imperial College. Dr Syed obtained her PhD in Molecular Immunology from Imperial College under the direction of Professor Margaret Dallman. After her PhD training she pursued her interests in translational cancer epigenetics at the Ludwig Institute of Cancer Research, London. Her main focus here centred on identifying cancer specific epigenetic changes that could be targets for therapy. She continued her research at the Institute of Cancer Research, London, where she played a key role in identifying a gene (Tip60) having a critical involvement in breast cancer development. In 2009 she returned to Imperial College to set up the John Fulcher Molecular Neuro-oncology Laboratory funded by the Brain Tumour Research Campaign (BTRC). Her programme of research investigates various aspects of brain tumour biology, genetics and epigenetics with a particular emphasis on identifying altered metabolic pathways to devise novel therapeutic strategies. Her lab has already generated novel data on deranged amino acid metabolism that she believes will form the basis of a phase 2 clinical trial of arginine depletion as a novel therapeutic strategy for brain tumours. Mr Babar Vaqas is a Neurosurgeon and Research Fellow at the Imperial College Healthcare NHS Trust.

Mr Vaqas is carrying out two cutting edge studies looking at new ways of diagnosing tumour tissue during surgery. Together with Mr O’Neill he is leading the first application of the iKnife system during Neurosurgery in the world. Earlier this year he used a laser probe to diagnose abnormal tissue during an operation to remove a brain tumour. This was the first time the technology had been used in Europe. His post as a neurosurgeon is supported by the Pickard Foundation and the project is supported by Brain Tumour Research Campaign (BTRC) and Brain Tumour Research (BTR). Mr Vaqas obtained his medical degree from the University of Oxford and completed basic surgical training in Cambridge.

Dr Matthew Grech-Sollars is a Research Associate in MRI physics working in the field of Neuro-Oncology Neuroimaging with Dr Adam Waldman. His key interest is in developing novel imaging techniques, with a particular focus on MRI, to improve clinical outcomes for patients with brain tumours, and a vision of having these methods integrated into clinical practice. Matthew joined Imperial College London in 2014, after receiving his PhD from University College London, titled “Diffusion MRI for characterising childhood brain tumours” and supervised by Prof Chris A Clark. Previously, he obtained his MSc in Biomedical Engineering with Medical Physics from Imperial College London in 2010, after having worked in industry as an Engineer for three years.

Oncology News | Neuro-oncology supplement 2016 | © McDonnell Mackie

Dr Fernando Abaitua has been a Postdoctoral Research Associate since 2013 in Dr Syed’s group at the molecular neuro-oncology John Fulcher Molecular laboratory, funded by BTRC, and is involved in multiple projects tackling epigenetic differences in cancer metabolism of the most aggressive form of brain tumours, glioblastoma multiforme. His projects are focused on the cellular and molecular mechanisms behind arginine deprivation and the role of collagen-prolyl hydroxylases in glioma biology, in the context of primary cell lines and isolated tumour stem cells under physiological oxygen conditions. Dr Combiz Khozoie, a Postdoctoral Fellow and Alexander Renziehausen, a PhD student are currently funded by the Barrow Neurological Foundation UK, a UK charity based in London that acts as the international fund-raising and education arm of the world-renowned Barrow Neurological Institute (BNI) in Phoenix, Arizona. Julia Langer is supported by a Grassini PhD studentship through BTRC, she is currently in the process of writing up her thesis. John DeFelice joined BTRC in 2011 as lab manager. The newest recruits include Richard Perryman, an MRC funded PhD student and Dr Tzouliana Stylianou, a BTRC funded postdoctoral fellow.

NEURO-ONCOLOGY SUPPLEMENT

Brain Tumour Research – the Research Centre Model Dr Kieran Breen is Director of Research at Brain Tumour Research which supports four dedicated centres of excellence across the UK. Correspondence address: E: Kieran@ braintumourresearch.org

hen it was established as a research-funding charity, Brain Tumour Research made a strategic decision to support Centres of Research Excellence within the UK rather than funding individual project and programme grants. These Centres were chosen following a strict peer review by international research experts. At the current time, the charity supports four Centres at the University of Portsmouth, Queen Mary University of London, Imperial College Healthcare NHS Trust (London) and Plymouth University Peninsula Schools of Medicine and Dentistry. The charity is dedicated to funding scientific research into all types of brain tumour. The establishment of a secure long-term funding partnership underpin the key salaried positions within the centres. The researchers are thus freed from the limitations and frustrations of applying for one research project grant after another. Instead they are allowed to pursue the sustainable and continuous research so desperately needed if we are to achieve our vision of finding a cure for brain tumours. The establishment of the centres also stimulates the interaction between both basic scientists and clinicians which is vital for the translation of lab-based discoveries into new cutting edge treatments, technologies, diagnostics and other interventions and bring them forward into a clinical setting. In order to be effective the centres require substantial levels of sustained funding in order that they can thrive, attract the foremost talent and ultimately produce worldclass research outputs. One of the key challenges within the current UK research infrastructure is the sparsity of opportunities for new researchers to join the “academic ladder”. Too often, we support promising postgraduate and postdoctoral researchers at the beginning of their careers. Because of the shortage of further opportunities in the area of brain tumour research, they are likely either to leave the country or exit from the neuro-oncology research space to other research areas for which more opportunities and support funding exist. The development of Brain Tumour Research-funded Research Centres of Excellence provides an infrastructure within which promising young scientists are provided with an opportunity to develop specialist brain tumour research expertise and knowledge. This will ultimately help them to realise their full

potential including through the application for personal research Fellowships and ultimately for tenured positions. Another key component of the research Centre model is to stimulate more junior researchers to move between centres within the network and thus encourage and facilitate the cross-pollination of the very best thinking at the cutting-edge of brain tumour research. The funding of Centres of Excellence stimulates the development of outstanding teams of collaborative researchers within both the academic and medical communities. This facilitates the development of long-term multidisciplinary strategic plans to explore new research avenues, that will bring us closer to that key breakthrough which the brain tumour world so desperately needs. This contrasts with, but also complements, the approach of developing one discrete project after another. Sometimes a long-term goal or a new field of research needs to be broken down into smaller parts, but that greater vision must be free to be held in the knowledge that it will be achieved. Our Centres collaborate to form a powerful network with each other as well as with other research facilities, both within the UK and internationally. This stimulates the acceleration of brain tumour research development and it will have a real clinical impact for those suffering from brain tumours, both in the shorter and the longer terms. But, there is a stark lack of funding available for research into the area of neuro-oncology. A recent report by the House of Commons Petitions Committee on “Funding for research into brain tumours” highlighted the real impact of a general lack of support for research in this area by successive Governments. The Governments have maintained the opinion that they have no role in making a decision of the specific areas of research that are funded but rather just to agree on an overall budget. The Committee however concluded that the Governments have “failed [brain] tumour patients” and “must put this right”. One of the key problems associated with the development of new and more effective therapies for brain tumours is the ability of drugs and other therapeutic agents to cross into the brain through the blood brain barrier. While some very effective drugs have been developed for the treatment of the more common cancers, these have not been demonstrated to be effective

Oncology News | Neuro-oncology supplement 2016 | © McDonnell Mackie

NEURO-ONCOLOGY SUPPLEMENT

for brain tumours. Therefore, while the five-year survival rates for breast and prostate cancers are over 80%, this rate is less than 20% for brain tumours. It is no coincidence that there is a correlation between clinical outcome and long-term research investment and this underlines neuro-oncology as an area of great unmet clinical need. The report concluded that the Government “should use its powerful influence on funding levels to send a clear message that brain tumour research is a major priority for the UK”. This can be achieved by ensuring that there is “adequate support for young people who wish to pursue a career in brain tumour research”. This is very much in keeping with Brain Tumour Research’s aim of establishing and nurturing new research talent. The report also highlights that the fact that the majority of research funding in this area is derived from the voluntary sector, such as Brain Tumour Research. The Government must now play its role as long term research cannot be dependent purely on public fundraising. The development of a research centre model can also help to overcome other research barriers that exist to prevent the development of a world-class neurooncology infrastructure within the UK. One obstacle is associated with tumour tissue collection and biobanking. It is vital that we obtain a better understanding of the process of tumour formation at a cellular level in order to be able to identify new drug targets and ultimately develop new and more effective drugs. Therefore, it is particularly important that the appropriate infrastructure is in place to make optimal use of the tissue samples as they become available, primarily following surgery. It has been reported that while 90% of patients would be keen for their tissue to be used for research following surgery, only 30% of patients have been given this opportunity. Some local procedures, and particularly those associated with ethical permission requirements, can have a significant impact on the process. An “opt in” approach, where patients are asked whether they would be willing to donate tissue following surgery, is currently used in the vast majority of centres. However, the introduction of an “opt-out” approach would simplify the process and lead to provision of more tissue for research and thus to acquisition of new knowledge to benefit patients. This would be particularly beneficial for the study of rarer tumours for which only a small number of samples

exist and it is essential that we maximize their collection. So, the development of a harmonised process is required with local ethics approval mirroring that obtained at a national level through the National Research Ethics Service. It is agreed that the process of tissue donation is a sensitive one and the appropriate staff, including research nurses, should be available to provide advice and support. This model, funded by the National Institute for Health Research, is already in existence for whole brain donation. A further barrier is the implementation of an appropriate technical framework in order to ensure consistency between collection centres. In some, for example, the tissue is used to derive cell lines that can be cultured and stored over a longer term. This requires very specific treatment of the tissue samples. The cell

identify both the format and location of the samples. They can request these for research use. However, this is largely supported locally by existing staff and facilities, many of whom are already overstretched due to a general increase in routine clinical requirements. In order to maintain the BATON research model, it is important to develop the appropriate infrastructure which will require investment at a national level. This will include the appropriate local pathology and clinical support. This is another area where the Government can invest into an infrastructural element that will facilitate additional research into brain tumours. A model for the development of a brain bank network has been developed within the UK and this could be used as a model for brain tumour biobanking.

“While the five-year survival rates for breast and prostate cancer are over 80%, this rate is less than 20% for brain tumours”

lines generated by Brain Tumour Research Centres of Excellence are available to other research centres throughout the country, again highlighting how the coordination of research centres at a national level can play a key role in the biobanking process. There is currently a coordinating centre (BRAIN UK Neurosurgical biopsy extension, BATON) which is hosted by the University of Southampton and funded by three charities Brain Tumour Research, Charlie’s Challenge and Brainstrust (www. brain-uk.org). To date, 26 (out of a possible 30) Neuropathology Centres throughout the UK have opted to be part of this virtual centre. For each of the samples, a pathology report can be provided. Although the tissue samples are held locally at the point of collection, the national database held at Southampton is available to researchers in order to

Oncology News | Neuro-oncology supplement 2016 | © McDonnell Mackie

While a chronic underinvestment in the area brain tumour research has been highlighted by the House of Commons Petitions Committee, this increased awareness has provided a window of opportunity within which the issue can be addressed. The support of the Brain Tumour Research Centres of Research Excellence play a key role in the development of a national network which will share research expertise and best practice. The Centres can also play a key role in the establishment and maintenance of national structures such as biobanking. But the Government must also appreciate that it has its role to play by consolidating the appropriate clinical, scientific and academic infrastructure which will allow brain tumour research to develop its full potential.

NEURO-ONCOLOGY SUPPLEMENT

New therapeutic approaches for the treatment of brain tumours Dr Kieran Breen is Director of Research at Brain Tumour Research which supports 4 dedicated centres of excellence across the UK Correspondence address: E: Kieran@ braintumourresearch.org

lioblastoma Multiforme (GBM) is the most common type of primary malignant brain tumour in adults, accounting for 54% of all gliomas. Approximately 0.59 to 3.69 GBM cases per 100,000 of the population are diagnosed annually worldwide. GBM is also one of the most lethal brain tumours, with only one-third of patients surviving for one year and less than 5% living beyond five years with an average survival of 12 to 15 months [4]. Therefore, the development of new and effective therapies for brain tumours, and GBM in particular, is a priority. While a number of key challenges exist, there are also promising treatment strategies being developed which could hold real hope for the future. When considering the development of new therapies, the first challenge is to ensure that the drug reaches its target within the brain. The blood brain barrier (BBB) prevents the entrance of many small drugs, in addition to larger molecules which have a therapeutic effect on the tumour cells, from entering the brain. One approach is to develop drugs attached directly to carrier proteins which bind to specific components of the BBB to facilitate their entry into the brain. A similar approach for targeting drug delivery is to load the drug into lipid vesicles which express the carrier protein in the outer membrane which can also transfer across the BBB [6]. Two particular receptor proteins have shown

particular promise. The transferrin receptor (TfR) is expressed at a low level in most human tissues but at a high level in brain capillary epithelial cells. Therefore, drugs which are conjugate to the transferrin protein (Tf) can cross the BBB more readily, resulting in an increase in brain levels of a drug. This can also be achieved using Tf-containing liposomes [9]. A second target is the low-density lipoprotein (LDL) receptor. Again, these are expressed at a high level in the BBB epithelium and also in glioma cells. The angiopep-2 protein, which binds to the LDL, can increase drug uptake into the brain and initial pre-clinical experiments have demonstrated that liposomal membranes containing angiopep-2 can readily be taken up into the brain and deliver small marker peptides into glioma cells [1]. Integrins are cell-surface proteins involved in communication between cells which are overexpressed on tumour cells. Although there are a number of potential peptide ligands which may target integrins, the most promising to date is the [c(RGDfK)] tripeptide. When it is attached to the surface of liposomes, it increases their uptake into tumour cells. One study reported an increase in the uptake of the drug paclitaxel which is currently used to treat ovarian, breast, lung and other non-brain tumours. This demonstrates that the development of an appropriate drug delivery strategy will increase the library of drugs that may be used to target brain tumour cells [10]. A similar drug, cilengitide,

Oncology News | Neuro-oncology supplement 2016 | ÂŠ McDonnell Mackie

NEURO-ONCOLOGY SUPPLEMENT

also binds to cell surface integrins and has undergone investigation. While this showed potential anti-tumour activity in pre-clinical models, a phase II clinical trial did not demonstrate any efficacy, either alone or when administered with temazolamide. This discrepancy highlights the challenge in translating the results obtained in pre-clinical studies into the clinical arena. The second challenge is to develop drugs that are effective in killing the tumour cells as some GBM cells have a particularly high resistance to currently employed radio- and chemotherapy approaches. A subclass of cells, termed GBM initiating cells (GIC), play a key role in the process of tumour initiation and sustained growth, and so represent a potential drug target. The bone morphogenic protein (BMP) is one of a group of compounds associated with the inflammatory response within the brain which reduces glioma cell growth and makes them more susceptible to conventional chemotherapy, including temozolamide. Early clinical studies have reported that glioma cells which themselves express higher levels of endogenous BMP, have a better clinical prognosis. However, the pre-clinical studies that have been carried out to date have used direct intracranial injections of the protein which would not be routinely clinically appropriate. A similar target is the CD133 protein which is expressed on cancer stem cells (CSCs) which are associated with increased tumour malignancy. Peripherally administered liposomes containing antibodies to CD133 bind and are taken up into tumour cells, leading to a significant increase drug levels within the cells [8]. CD133 has also been used as a target using the emerging chimeric antigen receptor (CAR-T) cell approach. These cells have been engineered to express the CD133specific antigen to target and ultimately kill CD133-positive CSCs, both in vitro and in a pre-clinical model [11]. Interestingly, the promising results using the CAR-T technology is associated with the entry of the immune cells into the brain, thus questioning the dogma that the brain is an immune privileged site. Activation of the epidermal growth factor receptor (EGFR) increases glioma cell proliferation and tissue invasion, and its expression is upregulated in up to 50% of glioblastoma cells. The tumour-specific mutation EGFRvIII is also expressed in

glioblastoma cells, making it an appealing therapeutic target. A number of strategies have been developed to inhibit receptor activation and therefore decrease tumour cell proliferation and penetration. Liposomes which contain an agent directed against EGFR, cetuximab, were reported to enhance their uptake and accumulation within the cells, although this was not observed in tumours which only expressed the EGFRvIII mutation, thus highlighting the potential selectivity of such cell-targeted approaches. A vaccine targeted against EGFRvIII receptor variant, rindopepimut, is currently undergoing phase II clinical trials with initial positive reports [3]. CAR-T cells have also been engineered to target both the EGFR and EGFRvIII epitopes and intracranial injections in pre-clinical models have reported positive results [5]. Another growth factor that has been identified as a therapeutic target is the vascular endothelial growth factor (VEGF) which binds the VEGF-R receptor to activate cell growth. This is expressed particularly by higher grade glioblastmas and is indicative of a poor treatment outcome. A study using the VEGF-R inhibitor, axitinib, has reported promising pre-clinical results [7]. However, a trial of an antibody directed against the VEGF peptide, bevacizumab, was unsuccessful in initial clinical trials. a subsequent analysis of the data suggested that a subgroup of patients demonstrated a positive response, so this warrants further research to be able to identify those who will respond to the therapy [2]. However, a clinical trial combining bevacizumab with rindopepimut represents an approach using complementary immunological approaches targeted against two proteins. Early results have reported potential clinical benefits [3]. In conclusion, while the library of existing treatments for brain tumours remains extremely limited at present, new technological approaches may provide the next-generation of therapies that will be more effective against brain tumours. This will address the key current challenges including access of the treatments to the tumour and the identification of new therapeutic targets which will be effective against the heterogeneous populations of brain tumour cells.

Oncology News | Neuro-oncology supplement 2016 | ÂŠ McDonnell Mackie

REFERENCES 1. Chiu RY, Tsuji T, Wang SJ, et al. Improving the systemic drug delivery efficacy of nanoparticles using a transferrin variant for targeting. J Control Release 2014;180:33-41. 2. Erdem-Eraslan L, van den Bent MJ, Hoogstrate Y. Identification of patients with recurrent glioblastoma who may benefit from combined bevacizumab and CCNU therapy: a report from the BELOB trial. Cancer Res 2016;76(3):525-34. 3. Gatson NT, Weathers SP, de Groot JF. ReACT Phase II trial: a critical evaluation of the use of rindopepimut plus bevacizumab to treat EGFRvIII-positive recurrent glioblastoma. CNS Oncol 2016 Jan;5(1):11-26. 4. Gigineishvili D, Shengelia N, Shalashvili G, et al. Primary brain tumour epidemiology in Georgia: firstyear results of a population-based study. J Neurooncol 2013;112:241-6. 5. Han J, Chu J, Keung Chan W, et al. CAR-engineered NK cells targeting wild-type EGFR and EGFRvIII enhance killing of glioblastoma and patient-derived glioblastoma stem cells. Sci Rep 2015;5:11483. 6. Karim R, Palazzo C, Evrard B, et al. Nanocarriers for the treatment of glioblastoma multiforme: Current state-of-the-art. J Control Release 2016 Feb 15. [Epub ahead of print] 7. Lu L, Saha D, Martuza RL, et al. Single agent efficacy of the VEGFR kinase inhibitor axitinib in preclinical models of glioblastoma. J Neurooncol 2015;121(1):91-100. 8. Shin DH, Lee SJ, Kim JS, et al. Synergistic effect of pliposomal gemcitabine and bevacizumab in glioblastoma stem cell-targeted therapy. J Biomed Nanotechnol 2015;11(11):1989-2002. 9. Tong H, Wang Y, Lu X, et al. On the preparation of transferrin modified artesunate nanoliposomes and their glioma-targeting treatment in-vitro and in-vivo. Int J Clin Exp Med 2015;8(12):22045-52. 10. Zhang P1, Hu L, Yin Q, et al. Transferrin-modified c[RGDfK]-paclitaxel loaded hybrid micelle for sequential blood-brain barrier penetration and glioma targeting therapy. Mol Pharm 2012;9(6):1590-8. 11. Zhu X, Prasad S, Gaedicke S, et al. Patient-derived glioblastoma stem cells are killed by CD133-specific CAR T cells but induce the T cell aging marker CD57. Oncotarget 2015;6(1):171-84.

NEURO-ONCOLOGY SUPPLEMENT

The therapeutic potential of targeting brain tumour metabolism through LDHA Cara Valvona, BSc, Final year PhD student, Brain tumour research centre, University of Portsmouth, UK. Correspondence to: cara.valvona@port.ac.uk

esearch into targeting tumour metabolism as a therapeutic approach has increased since it was added to the list of hallmarks of cancer in 2011 [1]. Lactate dehydrogenase A (LDHA) is a key enzyme involved in the Warburg effect, a metabolic pathway which appears to be universal in tumours, including primary brain tumours. Most studies on LDHA have been conducted in noncentral nervous system tumours, and although studies into inhibiting LDHA as a therapeutic target for brain tumours, presented in brief here, have shown promise in reducing tumour growth and migration, they are few in number and currently no LDHA inhibitors are available for clinical use.

Lactate dehydrogenase metabolism Lactate dehydrogenase (LDH) enzymes increase the rate of the reaction depicted in figure 1. LDHA has a high affinity for pyruvate, preferentially converting pyruvate to lactate and NADH to NAD+ whereas LDHB has a high affinity for lactate, preferentially converting lactate to pyruvate and NAD+ to NADH [2].

is available, a characteristic termed aerobic glycolysis or the Warburg effect, first observed by Otto Warburg in the 1920s [4]. Brain metabolism is complex and able to respond dynamically to changes in blood glucose and lactate concentrations [5]. In mouse and rat brains, LDHB mRNA expression is predominant with the exception of strong LDHA expression in the hippocampal regions CA1, CA2 and CA4, the ventromedian hypothalamic nucleus, and the dorsal raphe nucleus as well as moderate expression in the cerebral cortex [6]. However, studies have shown that the energy needs of the brain changes over a lifespan. The human brain uses high levels of aerobic glycolysis during foetal growth and development but then switches to oxidative phosphorylation which is seen predominantly in the adult brain [7].

LDHA and tumour malignancy LDHA over-expression is a common characteristic of cancers; it promotes elevated lactate concentrations which have been shown to predict tumour malignancy, recurrence, survival and metastasis in many types of cancer patients [3,8]. LDHA is also associated with other poor prognostic factors including tumour hypoxia [9], angiogenesis [10], proliferation and glucose uptake [11] as well as resistance to chemotherapy [12] and radiotherapy [13].

Deregulation of LDHA in brain tumours

Figure 1: The reaction catalysed by lactate dehydrogenase (LDH). Adapted from Valvona et al [3]. LDH catalyses the reversible conversion of pyruvate and NADH to lactate and NAD+.

Under normal physiological conditions, pyruvate is used to fuel oxidative phosphorylation and ATP production. However, when oxygen becomes scarce, ATP is produced using anaerobic glycolysis, which requires LDHA to convert pyruvate to lactate (Figure 1). Although it is less efficient at producing ATP, anaerobic glycolysis is 100 times faster than oxidative phosphorylation. Cancer cells upregulate LDHA to convert pyruvate to lactate in order to generate ATP via glycolysis even when oxygen 12

LDHA has long been known to be regulated by major transcription factors; hypoxiainducible factor 1 (HIF1) and c-Myc [9, 14]. HIF1 is often stabilised in brain tumours [15] and associated with a significantly poorer survival rate [16]. C-Myc expression is also often deregulated in brain tumour cells, including the medulloblastoma (MB) subgroup with the worst outcome (Group 3) [17], and has been shown to transform rat fibroblasts by up-regulating LDHA [14]. More recently forkhead box protein M1 (FOXM1) and Kruppel-like factor 4 (KLF4) have been shown to regulate LDHA transcription [18, 19]. FOXM1 is a marker of poor prognosis in MB [20] and regulates glioma tumourigenicity [21] whereas KLF4 is also suppressed in MB [22] and mutated in meningioma [23]. Like many enzymes, LDHA post-transcriptional activity is regulated by phosphorylation and acetylation of amino-acid

Oncology News | Neuro-oncology supplement 2016 | ÂŠ McDonnell Mackie

NEURO-ONCOLOGY SUPPLEMENT

Figure 2. Schematic showing processes that are reportedly affected by lactate dehydrogenase A (LDHA). Adapted from Valvona et al [3]. LDHA has been reported to be involved with the processes listed in the orange box. LDHA has also been reported to indirectly influence the processes listed in the red box via aerobic glycolysis and lactate production. Inhibition of LDHA obstructs aerobic glycolysis and the processes listed in the red and orange boxes. Cancer cells are then forced to use oxidative phosphorylation and pyruvate enters the mitochondria. This leads to reactive oxygen species (ROS) generation and apoptosis (green box).

residues. The oncogenic receptor tyrosine kinase FGFR1, expressed in meningioma and glioma [24], has been shown to directly phosphorylate LDHA at Y10 and Y83 [25]. Y10 phosphorylation of LDHA promotes active, tetrameric LDHA formation whereas phosphorylation of Y83 promotes NADH substrate binding [25]. Together these studies suggest that LDHA expression is commonly deregulated in a range of brain tumours.

LDHA and brain tumour growth and survival Reports predominantly indicate that LDHA suppression inhibits tumour cell proliferation and survival [3, 26]. Aerobic glycolysis benefits cancer cells by avoiding generation of reactive oxygen species by oxidative phosphorylation, and the intermediates of the citric acid cycle (required for oxidative phosphorylation) are utilised to synthesise the lipids, fatty acids and nucleotides required for rapid cell proliferation [27]. Interestingly, recent studies have demonstrated that LDHA is inhibited in the Isocitrate dehydrogenase (IDH) subgroup of glioblastoma (GBM) which characteristically has a slower progression, greater survival rates and better prognosis than the other GBM subgroups [28]. Even brain tumour stem cell (BTSC) lines which once had IDH mutations but lost their mutant IDH allele had silenced LDHA. Analysis of data from The Cancer Genome

Atlas and REMBRANDT public databases, revealed that low expression of LDHA and high methylation of the LDHA promoter was found in IDHmt GBM patients and glioma patients whose tumours overexpressed LDHA had a median survival of 16 months whereas patients whose tumour under-expressed LDHA had a median survival of >50 months [28]. These studies suggest that the silencing of LDHA in GBMs with IDH mutations may be responsible in part for the characteristically slow progression of IDH mutant GBMs.

LDHA and brain tumour migration and metastasis Secondary brain tumours, derived from other cancers such as breast, lung and melanoma, are the most common type of adult brain tumour and the reported incidence is rising. LDHA expression correlates with metastasis and poor patient prognosis in many tumours [11, 29]. The most frequently reported mechanism by which LDHA modulates cell migration and invasion is through lactate production. Lactate causes acidification of the microenvironment which promotes tumour cell invasion by inducing apoptosis of normal cells and pH-dependent activation of metalloproteinases (MMPs) and cathepsins which degrade the extracellular matrix and basement membranes [30, 31]. Seliger et al found that, in high grade glioma cell lines, the knockdown of LDHA resulted in a decrease in lactate

Oncology News | Neuro-oncology supplement 2016 | © McDonnell Mackie

concentrations which caused a reduction of THBS-1 and TGF-β2 expression and reduced migration by approximately 40% compared to the control [32]. Furthermore, addition of lactate or synthetic THBS-1 rescued TGF-β2 expression and glioma migration [32]. In another study it was found that MMP-2, which is over-expressed in high-grade glioma, is also up-regulated by LDHA through lactate induction of TGF-β2 [33]. It is probable that reducing lactate production through targeting LDHA would cause a reduction in metastasis and prolong patient survival.

LDHA and brain tumour evasion of the immune response Again, it is thought that lactate generation, promoted by LDHA, is the predominant cause of LDHA-mediated evasion of the immune response [34]. A study in GBMs revealed that LDHA induced the transcription and expression of natural killer group 2 member D (NKG2D) ligands on circulating monocytes and tumour infiltrating myeloid cells [35]. Chronic exposure to NKG2D ligands expressed by monocytes down-regulates the expression of NKG2D receptors on natural killer cells, preventing their ability to lyse NKG2D ligand-expressing tumour cells [36]. Previous studies in glioma have also shown that TGF-β can decrease NKG2D expression on NK cells in vitro [37]. As discussed previously, lactate production 13

NEURO-ONCOLOGY SUPPLEMENT

by LDHA activates TGF-β in glioma [33]; therefore it is possible that LDHA also activates TGF-β to promote evasion of the immune response.

LDHA and the brain tumour microenvironment LDHA can influence the tumour microenvironment through generation of lactate which lowers pH. Primary brain tumours have been found to have a mean pH of 6.8 and as low as 5.9 compared to normal brain tissue which has a pH of 7.1 [38]. It has also been shown that an acidic pH induces glioma stem cell markers and promotes angiogenesis and malignancy, furthermore in vitro elevation of pH reversed these effects [39]. Angiogenesis is a hallmark of many tumours, including GBMs, and is stimulated by angiogenic factors including VEGF and IL-8. An acute acidic extracellular pH has been shown to promote up-regulation of VEGF in human glioma cells independently of hypoxia and furthermore hypoxia and acidic pH did not have a synergistic effect on VEGF transcription [40].

LDHA therapy development There are several LDHA inhibitors which have been used in vitro and in vivo studies in many types of cancer including oxamate [41], Galloflavin [42], Mn(II) complexes [43], quinoline 3-sulfonamides [44], azido and alkyne compounds [45] and N-hydroxyindole-based (NHI) inhibitors [46], all of which show promise but still require refinement in terms of specificity, potency and reducing toxic effects. Unpublished studies by the Pilkington group have also shown that oxamate significantly reduces the proliferation and motility of MB cell lines. However in terms of brain tumours, Gossypol, a derivative of cotton seed oil, which inhibits LDHA and LDHC has shown the most promise [47]. Coyle et al found that gossypol treatment of mouse xenograft models decreased the mean weight of tumours by more than 50% and furthermore, the most sensitive glioma cell lines had higher LDHA expression levels [48]. Gossypol has been shown to be well tolerated in clinical trials and has also shown promise in recurrent malignant glioma trials [49, 50]. Two more clinical trials with gossypol and GBM have been completed (NCT00540722 and NCT00390403) but the results have not yet been published.

Summary Research has shown that LDHA and lactate are involved directly and indirectly in many aspects of tumour growth, migration, invasion and maintenance in a wide range of tumours (Figure 2) [3, 34]. Studies of LDHA and lactate in brain tumours have shown promise but the extent of these studies is severely lacking. Furthermore, targeting LDHA and tumour metabolism downstream of pyruvate synthesis is an attractive option as the effect on non-neoplastic cells should be minimal. Brain tumours are often more difficult to treat than other cancers as therapeutic drugs often have limited propensity to cross the protective blood-brain barrier (BBB). Although current available LDHA inhibitors are not approved for clinical use, to our knowledge, no groups have tested whether any potential LDHA inhibitors are even able to cross the BBB. This article is a brief summary of the function of LDHA and brain tumours which has been reviewed more extensively by Valvona et al [3]. 14

REFERENCES

1. Hanahan D and Weinberg RA. Hallmarks of cancer: the next generation. Cell 2011; Mar 144: 646-74. 2. Kopperschläger G and KirchbergerJ. Methods for the separation of lactate dehydrogenases and clinical significance of the enzyme. J Chromatogr B Biomed Appl 1996;684:25-49. 3. Valvona CJ, Fillmore HL, Nunn PB et al. The Regulation and Function of Lactate Dehydrogenase A: Therapeutic Potential in Brain Tumor. Brain Pathol 2015 Aug. 4. Warburg O. On respiratory impairment in cancer cells. Science 1956;124:269-70. 5. Overgaard M, Rasmussen P, Bohm AM, et al. Hypoxia and exercise provoke both lactate release and lactate oxidation by the human brain. FASEB J. 2012;26:301220. 6. Laughton JD, Charnay Y, Belloir B, et al. Differential messenger RNA distribution of lactate dehydrogenase LDH-1 and LDH-5 isoforms in the rat brain. Neuroscience 2000; 96:619-25. 7. Goyal MS, Hawrylycz M, Miller JA, et al. Aerobic glycolysis in the human brain is associated with development and neotenous gene expression. Cell Metab 2024;19:49-57. 8. Walenta S and Mueller-Klieser WF. Lactate: mirror and motor of tumor malignancy. Semin Radiat Oncol 2004;14:267-74. 9. Semenza GL, Jiang BH, Leung SW, et al. Hypoxia response elements in the aldolase A, enolase 1, and lactate dehydrogenase A gene promoters contain essential binding sites for hypoxia-inducible factor 1. J Biol Chem 1996;271:32529-37. 10. Kolev Y, Uetake H, Takagi Y, et al. Lactate dehydrogenase-5 (LDH-5) expression in human gastric cancer: association with hypoxia-inducible factor (HIF-1alpha) pathway, angiogenic factors production and poor prognosis. Ann Surg Oncol 2008;15:2336-44. 11. Grimm M, Alexander D, Munz A, et al. Increased LDH5 expression is associated with lymph node metastasis and outcome in oral squamous cell carcinoma. Clin Exp Metastasis 2013;30:529-40. 12. Koukourakis MI, Giatromanolaki A, Sivridis E, et al. Prognostic and predictive role of lactate dehydrogenase 5 expression in colorectal cancer patients treated with PTK787/ZK 222584 (vatalanib) antiangiogenic therapy. Clin Cancer Res 2011;17:4892-900. 13. Koukourakis MI, Giatromanolaki A, Panteliadou M., et al. Lactate dehydrogenase 5 isoenzyme overexpression defines resistance of prostate cancer to radiotherapy. Br J Cancer 2014;110:2217-23. 14. Shim H, Dolde C, Lewis BC, et al. c-Myc transactivation of LDH-A: implications for tumor metabolism and growth. Proc Natl Acad Sci USA 1997;94:6658-63. 15. Reszec J, Rutkowski R, and Chyczewski L. The expression of hypoxia-inducible factor-1 in primary brain tumors. Int J Neurosci 2013;123:657-62. 16. Lu R, Jiang M, Chen Z, et al. Lactate dehydrogenase 5 expression in Non-Hodgkin lymphoma is associated with the induced hypoxia regulated protein and poor prognosis. PLoS One 203;8:e74853. 17. Taylor MD, Northcott PA, Korshunov A, et al. Molecular subgroups of medulloblastoma: the current consensus. Acta Neuropathol 2012;123:465-72. 18. Cui J, Shi M, Xie D, et al. FOXM1 Promotes the Warburg Effect and Pancreatic Cancer Progression via Transactivation of LDHA Expression. Clin Cancer Res 2014 Apr. 19. Shi M, Cui J, Du J, et al. A Novel KLF4/LDHA Signaling Pathway Regulates Aerobic Glycolysis in and Progression of Pancreatic Cancer. Clin Cancer Res 2014;20:4370-80. 20. Priller M, Pöschl J, Abrão L, et al. Expression of FoxM1 is required for the proliferation of medulloblastoma cells and indicates worse survival of patients. Clin Cancer Res 2011;17:6791-801. 21. Liu M, Dai B, Kang SH, et al. FoxM1B is overexpressed in human glioblastomas and critically regulates the tumorigenicity of glioma cells. Cancer Res 2006;66:3593602. 22. Nakahara Y, Northcott PA, Li M, et al. Genetic and epigenetic inactivation of Kruppel-like factor 4 in medulloblastoma. Neoplasia 2010;12:20-7. 23. Reuss DE, Piro RM, Jones DT, et al. Secretory meningiomas are defined by combined KLF4 K409Q and TRAF7 mutations. Acta Neuropathol 2013;125:3518. 24. Ueba T, Takahashi JA, Fukumoto M, et al. Expression of fibroblast growth factor receptor-1 in human glioma and meningioma tissues. Neurosurgery 1994;34:221-5; discussion 225-6. 25. Fan J, Hitosugi T, Chung TW, et al. Tyrosine phosphorylation of lactate dehydrogenase A is important for NADH/NAD(+) redox homeostasis in cancer cells. Mol Cell Biol 2011;31:4938-50.

Oncology News | Neuro-oncology supplement 2016 | © McDonnell Mackie

NEURO-ONCOLOGY SUPPLEMENT

26. Le A, Cooper CR, Gouw AM, et al. Inhibition of lactate dehydrogenase A induces oxidative stress and inhibits tumor progression. Proc Natl Acad Sci USA 2010;107:2037-42. 27. Vander Heiden MG, Cantley LC, and Thompson CB. Understanding the Warburg effect: the metabolic requirements of cell proliferation. Science 2009;324;1029-33. 28. Chesnelong C, Chaumeil MM, Blough MD, et al. Lactate dehydrogenase A silencing in IDH mutant gliomas. Neuro Oncol 2014;16:686-95. 29. Brizel DM, Schroeder T, Scher RL, et al. Elevated tumor lactate concentrations predict for an increased risk of metastases in head-and-neck cancer. Int J Radiat Oncol Biol Phys 2001;51:349-53. 30. Kato Y, Lambert CA, Colige AC, et al. Acidic extracellular pH induces matrix metalloproteinase-9 expression in mouse metastatic melanoma cells through the phospholipase D-mitogen-activated protein kinase signaling. J Biol Chem 2005;280:10938-44. 31. Goetze K, Walenta S, Ksiazkiewicz M, et al. Lactate enhances motility of tumor cells and inhibits monocyte migration and cytokine release. Int J Oncol 2011;39:453-63. 32. Seliger C, Leukel P, Moeckel S, et al. Lactate-Modulated Induction of THBS-1 Activates Transforming Growth Factor (TGF)-beta2 and Migration of Glioma Cells In Vitro. PLoS One 2013;8: e78935. 33. Baumann F, Leukel P, Doerfelt A, et al. Lactate promotes glioma migration by TGF-beta2-dependent regulation of matrix metalloproteinase-2. Neuro Oncol 2009;11:368-80. 34. Hirschhaeuser F, Sattler UG, Mueller-Klieser W. Lactate: a metabolic key player in cancer. Cancer Res 2011;71:6921-5. 35. Crane CA, Austgen K, Haberthur K, et al. Immune evasion mediated by tumor-derived lactate dehydrogenase induction of NKG2D ligands on myeloid cells in glioblastoma patients. Proc Natl Acad Sci USA 2014 Aug. 36. Oppenheim DE, Roberts SJ, Clarke SL, et al. Sustained localized expression of ligand for the activating NKG2D receptor impairs natural cytotoxicity in vivo and reduces tumor immunosurveillance. Nat Immunol, vol. 6, pp. 928-37, Sep 2005. 37. Crane CA, Han SJ, Barry JJ, et al. TGF-beta downregulates the activating receptor NKG2D on NK cells and CD8+ T cells in glioma patients. Neuro Oncol 2010;12:7-13. 38. Vaupel P, Kallinowski F, and Okunieff P. Blood flow, oxygen and nutrient supply, and metabolic microenvironment of human tumors: a review. Cancer Res 1989;49:6449-65. 39. Hjelmeland AB, Wu Q, Heddleston JM, et al. Acidic stress promotes a glioma stem cell phenotype. Cell Death Differ 2011;18:829-40. 40. Fukumura D, Xu L, Chen Y, et al. Hypoxia and acidosis independently up-regulate vascular endothelial growth factor transcription in brain tumors in vivo. Cancer Res 2001;61:6020-4. 41. Zhai X, Yang Y, Wan J, et al. Inhibition of LDH-A by oxamate induces G2/M arrest, apoptosis and increases radiosensitivity in nasopharyngeal carcinoma cells. Oncol Rep 2013;30:2983-91. 42. Farabegoli F, Vettraino M, Manerba M, et al. Galloflavin, a new lactate dehydrogenase inhibitor, induces the death of human breast cancer cells with different glycolytic attitude by affecting distinct signaling pathways. Eur J Pharm Sci 2012;47:729-38. 43. Xue JJ, Chen QY, Kong MY, et al. Synthesis, cytotoxicity for mimics of catalase: Inhibitors of lactate dehydrogenase and hypoxia inducible factor. Eur J Med Chem 2014;80C:1-7. 44. Billiard J, Dennison JB, Briand J, et al. Quinoline 3-sulfonamides inhibit lactate dehydrogenase A and reverse aerobic glycolysis in cancer cells. Cancer Metab 2013;1:19. 45. Moorhouse AD, Spiteri C, Sharma P, et al. Targeting glycolysis: a fragment based approach towards bifunctional inhibitors of hLDH-5. Chem Commun (Camb) 2011;47:230-2. 46. Granchi C, Roy S, Giacomelli C, et al. Discovery of N-hydroxyindole-based inhibitors of human lactate dehydrogenase isoform A (LDH-A) as starvation agents against cancer cells. J Med Chem 2011;54:1599-612. 47. Lee CY, Moon YS, Yuan JH, et al. Enzyme inactivation and inhibition by gossypol. Mol Cell Biochem 1982;47:65-70. 48. Coyle T, Levante S, Shetler M, at al. In vitro and in vivo cytotoxicity of gossypol against central nervous system tumor cell lines. J Neurooncol 1994;19:25-35.

International Symposium on Pediatric Neuro-Oncology 2016 Dear Colleagues and Friends of the Pediatric Neuro-Oncology Community. The 17th International Symposium on Pediatric NeuroOncology (ISPNO) in 2016 is taking place from 12th - 15th June in the vibrant and cosmopolitan city of Liverpool. The venue for the conference is the award winning Liverpool Convention Centre set on a delightful waterfront that has achieved world heritage. The biennial ISPNO meeting has become the pre-eminent event in the field of Pediatric Neuro-Oncology, being the only global meeting of the multi-disciplinary international community of professionals involved in the research, diagnosis, treatment and rehabilitation of infants, children and young people with Central Nervous System tumours.

ISPNO 2016 Liverpool will feature:

• A full programme of plenary and poster sessions, keynote talks and round table discussions covering all the main aspects of CNS tumours in children and young people. • A day dedicated to Neuro-oncological surgery - with leading international experts in Pediatric Neurosurgery. • A full day neuro-oncology nurses meeting and a reception for nurses hosted by The Brain Tumour Charity. • A pre-meeting Education day with state of the art lectures given by world-class clinicians and scientists. • An open meeting of Posterior Fossa Society. • A Family Day. We will offer a memorable networking and social program with the Welcome Reception at the brilliantly designed waterside Museum of Liverpool, a fantastic gala dinner and optional social events at the Cavern Club – home of the Beatles – or a Latin themed evening.

For all conference information please visit

www.ISPNO2016.com We look forward to welcoming the International Pediatric Neuro-Oncology community to Liverpool. Together we will create an incredible meeting. With Very Best Wishes Professor Barry Pizer Chair of the Local Organising Committee of ISPNO 2016 - Liverpool.

49. Bushunow P, Reidenberg MM, Wasenko J, et al. Gossypol treatment of recurrent adult malignant gliomas. J Neurooncol 1999;43:79-86. 50. Stein RC, Joseph AE, Matlin SA, et al. A preliminary clinical study of gossypol in advanced human cancer. Cancer Chemother Pharmacol 1992;30:480-2.

Oncology News | Neuro-oncology supplement 2016 | © McDonnell Mackie

NEURO-ONCOLOGY SUPPLEMENT

Malignant Gliomas and long term survivorship – exploring the vital role of the Neuro-Oncology Specialist Nurse Ingela Oberg, Neuro Oncology Specialist Nurse, Addenbrooke’s Hospital, Cambridge, UK. Correspondence to: E: ingela.oberg@ addenbrookes.nhs.uk

done by us as health care professionals to lessen s is well documented, there are the gap, but how does this survival gap impact on around 8,600 patients in the UK each the overall wellbeing of our glioma patients? This year diagnosed with a primary brain article aims to explore some of the shortcomings tumour. It is also well accepted that concerning long term follow up and care of this number is greatly under represented as around the glioma patient, what is required to change half of all brain tumours are not being reported to outcomes for the better and why neuro-oncology the cancer registries and furthermore secondary nurses are pivotal to this process. (metastatic) brain tumours are not recorded at all Recent research carried out by Brainstrust states as they are monitored against their primary cancer people living with a malignant brain tumour face site [1]. According to the Brainstrust charity, the a barrage of uncertainty and feel increasingly estimated number of people therefore living with isolated and alone [4]. Place this isolation alongside an intracranial tumour in 2013 is currently just the fact the NHS currently struggles to sufficiently under 55,500 [2] (see diagram). support the increasing number of cancer survivors According to the most recent figures for 2011 within its existing service structures and you have published by Cancer Research UK, nearly half of a recipe for a disastrous long term follow-up all cancer sufferers in England and Wales survive strategy and patient satisfaction [5]. This is further at least a decade, but sadly this is not the case for compounded by the fact as many as 1 in 4 brain adults diagnosed with malignant brain tumours, tumour patients still do not know who to contact where only 15% survive 10 years [3]. This startling Prevalence of intracranial tumours September for help or support even though The National contrast means there remains a lot of–work to be 2013

Living with a brain tumour

The impact of a brain tumour doesn’t stop when you’ve been diagnosed. In fact for patients and carers across the UK the fight is so much more than the diagnosis. We know.

Living with a brain tumour

There are currently over 55,000 people in England living with or beyond a brain tumour diagnosis. The brainstrust community is here to ensure that those affected by a brain tumour diagnosis get the care and help they need to lead the life they want to for as long as possible. Prevalence of intracranial tumours – September 2013 The impact of a brain tumour doesn’t stop when you’ve been diagnosed. In fact for patients and carers across the UK the fight is so much more than the diagnosis. We know. There are currently over 55,000 people in England living with or beyond a brain tumour diagnosis. The brainstrust community is here to ensure that those affected by a brain tumour diagnosis get the care and help they need to lead the life they want to for as long as possible.

Prevalent cases of intracranial tumours

Glioblastoma: 2.00%

Identified on the Encore database – September 2013

Astrocytoma Grade 1–3: 8.77%

Glioma low Grade: 1.30% Glioma Grade unknown: 6.61%

Intracranial endocrine: 24.67% Pituitary adenoma: 19.62%

Medulloblastoma: 1.77%

Benign uncertain unspecified other: 3.42%

Benign uncertain unspecified other: 6.68%

Malignant: 1.41%

Malignant uncertain unspecified other: 2.44%

Pineal: 0.22%

Intracranial endocrine: 24.67%

55,498

Cranial nerves: 15.38%

Nerve sheath tumour benign uncertain: 12.24%

Benign uncertain unspecified other: 1.99%

Cranial nerves: 15.38%

Cerebral meninges: 29.36%

Malignant uncertain unspecified other: 1.15%

ARE ENOUGH

PEOPLE IN ENGLAND

LIVING WITH, AND BEYOND A BRAIN TUMOUR

DIAGNOSIS

157

JUMBO JETS OR

Cerebral meninges: 29.36%

Meningioma Grade 1–2: 26.28% Meningioma Grade 3: 0.74%

** Excludes increase Excludes London London and and the the South South East, East, we we can can assume assume aa 10–20% 10–20% increase in total prevalence to take into account these areas.

THAT MEANS

THAT THERE

TO FILL

Brain: 29.57%

people living with a brain tumour in England*

CNS unspecified: 1.01%

Brain: 29.57%

Developed with the National Cancer Registration Service of Public Health England

1,057 BUSES

Benign uncertain unspecified other: 2.21%

Malignant uncertain unspecified other: 0.13%

NEURO-ONCOLOGY SUPPLEMENT

Institute of Clinical Excellence (NICE) in 2006 called for all brain tumour patients to have access to a Key worker, likely to be a clinical nurse specialist (CNS) as part of their Improving outcomes guidance [6].

Access to key workers Having an authoritative point of contact, such as a CNS, is proven to lessen patient’s anxiety and increase satisfaction with regard to their holistic care needs – specialist nurses help improve the patient experience and safety because they have in-depth knowledge of the physical, psychological and social effects of their specific condition and play a key role in the management of patient care [7]. CNS’s are pivotal in that we build up a rapport with both the patients and their families, and are able to offer tailored care depending on the patient’s level of need. According to Fletcher, CNSs reduce both unnecessary hospital admissions and readmissions, they reduce waiting times, free up the consultant’s time to treat other patients, improve access to care, and help support patients in the community [8]. So why is it that as many as 1 in 4 are still not aware of who their CNS / Key worker is when it comes to neuro-oncology [9]? It is fairly evident that those patients with high grade, primary malignant tumours requiring neurosurgery, chemotherapy and/or radiotherapy will encounter specialist nurses on a near daily basis and will have rafts of information, both verbal and written, given to them [10]. However, those patients with slow growing (low grade) glioma on a “watch and wait policy” are a different scenario completely – they are the ones at risk of slipping through the follow up loop, with no point of contact. In my experience, I’ve found some patients are followed up by GP’s only, others by neurologists, oncologists, neurosurgeons and/or specialist nurses, while some are without follow up at all. Personally, I feel the fragmented and uncoordinated care of these patients should be streamlined at a national level with minimum standards set and clear patient pathways, which should include regular follow-up with surveillance MRI scans and access to a clinical nurse specialist.

Savings to the health economy Nurse led telephone clinics, for example, provides an alternative approach to conventional outpatient clinics and ensures the focus is moved away from

cancer surveillance to a model of patient centred support, with evidenced high patient satisfaction [11]. Recent studies have shown that referrals from GPs and Consultants to specialist nurse clinics are steadily on the rise with over 100,000 patients on average per year between 2005 and 2010. This proves specialist nurses have a much greater role today in the delivery of healthcare than they did even five years ago [12]. Furthermore, outside of the structured clinic format, it is estimated that specialist nurses field around 100 phone calls per week from patients, relatives and primary care workers. Telephone consultations also save £72,588 per nurse to the national health economy by reducing the number of GP appointments [13]. For the thousands of people across the UK living with long term conditions, including cancer, several studies have shown that specialist nurses are both clinically- and cost-effective [14]. A CNS specialising in cancer care will see an average of 13 follow-up patients per week in an outpatient setting. Matched against Department of Health tariffs this represents £53,040 in income and the potential release of 13 slots to new patients (raising £159,120 per 48 week year). This means CNSs working with cancer patients can speed up pathways, help trusts meet targets, allow new patients to be seen and therefore help generate more income [14]. Having demonstrated the value of the specialist nurse, both financially and in the delivery of healthcare, how can they be best utilised to help shape the healthcare of the future for brain tumour patients and to help improve outcomes?

Service reconfigurations – The Cambridge Model In Cambridge, we have successfully streamlined our neuro-oncology service in accordance with the recommendations from the IOG guidance regarding the key aspects of neuro oncology services that needed developing. This included establishing direct referral pathways, implementing a specialist MDT and having a dedicated neuro-oncology clinic headed up by subspecialised neurosurgeons [6]. Resulting from this reconfiguration, our service has evolved from being an unplanned, consultant centric process of care to one which is now mainly outpatient based, consultant led and patient centred [15]. This service reconfiguration,

known as the Cambridge model, benefits patients by significantly reducing their length of stay, having a pre-planned surgery date to work towards, having a firm point of contact for the CNS’s involved and allowing safe but early discharge home. Clinics headed up by not only the dedicated neuro-oncology consultants but two dedicated neuro-oncology specialist nurses allows for uninterrupted clinics to run on a weekly basis. The CNSs are able to assess the overall holistic wellbeing of patients and there is an opportunity for wound assessment, removal of surgical clips or sutures, steroid reduction and review of anticonvulsant medication. The clinic runs on the same day as the specialist MDT, allowing for patients to be rapidly reviewed the same day as their MDT discussion, thus minimising delays to their patient pathways and any treatment plans. At the core of all this, arranging admissions, discharges, onward treatment referrals, booking of scans and pre- / post-operative review is the specialist nurse. It has been estimated that nurseled discharges facilitated by a streamlined service supported by the CNSs saves over £1,000.00 per patient in cost of inpatient stay and imaging [15].

Neuro-oncology Nurse Consultant – scope for further improvements Taking the Cambridge Model of reconfiguration one step further, it is clear to me that significant investments into neuro-oncology specialist nurses need to be made in order to ensure every patient diagnosed with a brain tumour has access to a specialist nurse to help manage not only their pathway as efficiently as possible, but to also provide vital support and information to them and their carers. Currently around 1/3 of all UK based Neuro-oncology CNSs are Macmillan funded [13] – myself included. I strongly believe that access to specialist nurses in the NHS is not something the charitable sector should finance; this is something the Government should fund. Currently high on the agenda with lobbying groups, neuro-oncology working groups and the charitable sector is the issue of having access to neuro-rehabilitation and enabling timely transition to the community sectors for those patients needing on-going support and care away from the acute hospital environment [4,9]. Allowing patients to recover their maximal neurological 17

NEURO-ONCOLOGY SUPPLEMENT

potential and / or to die at home instead of in a hospital should be facilitated where feasible. In my opinion, these evolving roles are inevitably seen as belonging to the ever increasing remit of the CNS, stretching beyond the hospital environment into the community sector. In reality however, CNS’s workload and time constraints prohibits them from fully engaging with this process. In order to ensure patients fulfil the potential to optimise their neuro-rehabilitation and to be able to lead as long and fulfilling lives as possible, we need to ensure they are adequately assessed regarding their complex rehabilitation needs and in ensuring there is ample involvement with the community sector, even prior to discharge. This needs to be streamlined by someone specialising in neuro-oncology with firm leadership abilities and proven change management, and in my opinion this is the perfect time to consider introducing nurse consultants into the neurooncology field. It’s time to make brain tumour patients stand head and shoulders above the parapet – so let’s ensure neuro-oncology leads by example and let other cancer disciplines follow suit. It’s time to make brain tumours count, both statistically and realistically.

REFERENCES 1. Cancer Statistics registrations: Registrations of cancer diagnosed in 2007, Office for National Statistics, England. Series MB1 no.38. 2010, National Statistics: London; Cancer Registrations in Wales 2007, Welsh Cancer Intelligence and Surveillance Unit, 2010; Cancer of the Brain and CNS: Scotland: trends in incidence 1985-2007, ISD Scotland, 2010, Information and Statistics Division, NHS Scotland; Cancer Incidence and Mortality, Northern Ireland Cancer Registry, 2010. 2. Brainstrust: Living with a brain tumour. Prevalence of intracranial tumours – September 2013 http://www.brainstrust.org.uk/ 3. Cancer Research UK http://www.cancerresearchuk.org/about-cancer/type/brain-tumour/treatment/ statistics-and-outlook-for-brain-tumours#reliable (accessed April 2015) 4. Brainstrust. Quality of Life: what the brain cancer community needs http://www.brainstrust.org.uk/ 5. Macmillan Cancer Support, Department of Health and NHS Improvement. National Cancer Survivorship Initiative (NCSI) Living with and Beyond Cancer: Taking Action to Improve Outcomes. 6. National Institute for Health and Clinical Excellence. Guidance on Cancer Services – Improving outcomes for People with Brain and Other CNS Tumours, The Manual. June 2006. 7. Thornton M, et al. Hard choices: a qualitative study of influences on the treatment decisions made by advanced lung cancer patients. International Journal of Palliative Nursing. 2011;17(2):68-74. 8. Fletcher M. Assessing the value of specialist nurses. Nursing Time 2011;107:30-1. 9. The Brain Tumour Charity. Finding a better way? Improving the quality of life for people affected by brain tumours: Report of a survey of people affected by brain tumours and their carers. (2013) p34. 10. NHS England. National Cancer Patient experience Survey 2014. 11. Sardell S, et al. Evaluation of a Nurse-Led Telephone Clinic in the Follow-up of Patients with Malignant Glioma. Clinical Oncology 2000;12(1):36-41. 12. Trevatt P, Petit J, Leary A. Cancer Nursing Practice. Mapping the English cancer clinical nurse specialist workforce. 2008. 13. Macmillan (2014) Impact Briefs – Clinical Nurse Specialists www.macmillan.org.uk/Documents/AboutUs/ Research/ImpactBriefs/ImpactBriefs-ClinicalNurseSpecialists2014.pdf 14. Royal College of Nursing (2010). Guidance on Safe Nurse Staffing Levels in the UK. www.rcn.org.uk/__data/assets/pdf_file/0005/353237/003860.pdf (accessed April 2015). 15. Guilfoyle M, et al. Implementation of neuro-oncology service reconfiguration in accordance with NICE guidance provides enhanced clinical care for patients with glioblastoma multiforme. British Journal of Cancer 2011;104:1810-5.

BNOS 2016

TRIALS, TECHNOLOGIES & T CELLS 29 June to 1 July The University of Leeds

REGISTRATION OPEN

bnos2016.org.uk bnos16@leeds.ac.uk

BRINGING TOGETHER THE BEST OF BASIC SCIENCE AND CLINICAL RESEARCH IN NEURO ONCOLOGY SPEAKERS Gelareh Zadeh University of Toronto Richard Vile Mayo Clinic Richard J. Gilbertson University of Cambridge

Nicola Sibson Oxford Institute for Radiation Oncology Luisa Ottobrini University of Milan Bernhard Radlwimmer Heidelberg University Sebastian Brandner University College London

THEMES Immunotherapy Novel Technologies Clinical Studies

Education day Career workshops Science networking sessions

NEURO-ONCOLOGY SUPPLEMENT

Dysregulation of Histone Deacetylases in paediatric brain tumours

Emily Pinkstone, BSc, MSc, PhD Student University of Portsmouth, Brain Tumour Research Centre.

he World Health Organization (WHO) grades tumours in four stages where grades I and II are benign tumours with a slower proliferation rate, grade III is malignant, with increased proliferation and histological features such as nuclear atypia while grade IV comprise malignant tumours that are highly proliferative with areas of necrosis and carry a very poor prognosis [1]. Paediatric high grade gliomas (pHGG) are a histologically heterogeneous group and distinct from adult gliomas with their unique epigenetic and genetic characteristics. pHGG include diffuse intrinsic pontine gliomas (DIPG) and gliomatosis cerebri which respond poorly to treatment and represent the leading cause of paediatric brain cancer mortality [2]. A 2010 report stated that the incidence of paediatric brain tumours did not change in the 20 years between 1986 and 2006, while in the 10 years before that, the incidence had increased [3]. Defects in chromatin remodelling appear to be central to the pathobiology of pHGG. Chromatin is comprised of nucleosomes, DNA wrapped around an octamer of core histones, compacted together to form a chromosome. The chromatin structure is unravelled and compacted to allow the transcription of genes

as required. Post-translational modifications are changes in the DNA that affect gene expression without altering the sequence of base pairs, such as acetylation, methylation and phosphorylation, and are controlled through chromatin remodelling enzymes.

Histone Deacetylases Chromatin remodelling enzymes, such as histone acetyltransferases (HATs) and histone deacetylases (HDACs) modify the structure of the chromatin by the addition (HATs) or removal (HDACs) of acetyl groups (depicted in Figure 1) to lysine amino acids present at the N-termini. Addition of acetyl groups decreases binding affinity of the histones to the DNA backbone by neutralising the positive charge of amine groups located on the lysine and arginine amino acids [4,5]. Chromatin is able to relax and expand allowing room for transcription machinery to bind. Removal of acetyl groups increases the positive charge of the histone tails so encouraging binding affinity to the negatively charged phosphate groups on the DNA backbone, causing compression of the chromatin structure [4,5]. HDACs are grouped in relation to their structure, cellular localisation and homology

Figure 1: Graphical representation of how histone deacetylases (HDACs) and histone acetyltransferases (HATs) effect chromatin structure and consequencely transcription. TM â&#x20AC;&#x201C; transcription machinery

Oncology News | Neuro-oncology supplement 2016 | ÂŠ McDonnell Mackie

NEURO-ONCOLOGY SUPPLEMENT

with yeast HDAC proteins. There are 4 zinc dependent groups; I, IIa, IIb and IV with group III containing nicotinamideadenine-dinucleotise (NAD)-dependent sirtuins. Group I contains HDACs 1, 2, 3 and 8 and are homologous to Rpd3 (reduced potassium dependency 3), a yeast transcriptional regulator, group IIa, containing HDACs 4, 5, 7, 9a and 9b and group IIb containing HDAC6 and 10 are homologous to Hda1 (histone deacetylase 1) in yeast [6]. Group IV contains HDAC11, classed by itself as it is phylogenetically different from groups I and II [6]. Groups I, II and IV share the same enzymatic mechanism of action where the acetyl-lysine amide bond is hydrolysed when a zinc atom binds to the HDAC [6].

HDAC Function in Healthy Cells HDACs are known to be required in many cellular processes on top of transcriptional regulation such as apoptosis, DNA damage repair, cell cycle control, autophagy, metabolism and senescence [7]. HDACs are expressed in the normal functioning brain [8] at differing levels dependent on cell type and function and are critical is learning, memory and neural development.

HDAC Function in Neural Development A 2009 study showed that when HDAC1 and 2 were deleted simultaneously, mice developed tremors associated with myelin deficiency [9]. There was complete loss of both oligodendrocyte precursor cell markers and mature oligodendrocyte markers in the spinal cord and brains of these mice too suggesting HDAC1 and HDAC2 are required for oligodendrogenesis and oligodendrocyte differentiation, yet the loss of HDAC1 and HDAC2 did not impact upon other neural cell types in the developing CNS [9]. However, another study using a similar model showed loss of HDAC1 and HDAC2 caused mice to have smaller brains with a compacted cerebellum [10]. Defects were also found in the cortex, hippocampus and cortical laminar organisation [10]. Significant neuronal abnormalities were also observed and Purkinje cells did not migrate from the nuclei of the cerebellum, preventing 20

normal cerebellar growth [10]. This study suggests HDAC1 and HDAC2 are essential in neural development. HDAC2 and 3 have been found to bind to genes associated with transcription regulation of differentiation and development in rat brain neural stem cells [11]. HDAC2 and HDAC3 were enriched at promoters of genes, associated with neuronal and oligodendrocyte differentiation [11]. Valproic acid, an HDAC inhibitor, was shown to promote oligodendrocyte differentiation and morphological changes such as formation of myelin plaque-like structures and an increase in oligodendrocyte radius when in combination with a thyroid hormone (T3) [11]. Data showed HDAC2 may be needed for SOX10 gene regulation, required for terminal oligodendrocyte differentiation, in early oligodendrocyte development [11]. HDAC3 has also been reported to repress neuronal genes and differentiation in embryonic neural stem cells [11] showing multiple roles for HDAC’s in neural development. Class II HDACs have also been shown to be essential in the development of the brain. HDAC6 was found to play a critical role in dendrite development through interaction with Cdc20 in neuronal centrosomes [12] and HDAC9 was shown to translocate from the nucleus to the cytoplasm with maturation of cortical neurons [13]. When replaced with a mutant HDAC9, total length of dendritic branches was significantly reduced suggesting HDAC9 is required for the proper development of these cells [13]. HDAC10 has been found to interact with the transcription factor Pax3, which is needed for normal neural crest development, among other processes [14]. Oligodendrocyte differentiation depends on HDAC activity to form morphological changes characterised as primary, secondary and tertiary branches [15]. Differentiating progenitors treated with HDAC inhibitors were unable to form branches [15]. Conversely, a 2004 study found that the HDAC inhibitor VPA, promoted neuronal differentiation in foetal neural stem cell cultures [16] showing that potentially HDACs, and consequently HDAC inhibitors, can have both positive and negative effects on neural development dependent on timing and cell type.

Neural Development and Brain Tumours There is increasing evidence that gliomas in childhood could have multiple different cells of origin including neural stem cells, glial progenitor cells, oligodendrocyte progenitor cells and astrocytes [17]. Gliogenesis continues throughout the first year of life [18], precursor cells in the ventral pons peaks in neonates and at around age 6 [19] and myelination continues to early adulthood [20,21,22]. The extent of neural proliferation throughout childhood increases the likelihood of a mutation, and subsequent tumour development, occurring. Aberrant proliferation of pontine-like precursor cells, is caused by dysregulation of neuronal activity during development and these express SOX2, nestin, Olig2 and vimentin [19], also found to be expressed in DIPG, indicating that disruption of neurodevelopmental processes could lead to tumourigenesis. Epigenetics is crucial in regulating differentiation and thus it’s role in paediatric brain tumour development is indisputable [23].

Dysregulation of HDACs in Childhood Brain Tumours Given the essential and critical roles of HDACs, it is not surprising that dysregulation of these proteins are implicated in tumourigenesis. Inhibitors of HDACs are in clinical trials for treatment of a variety of cancers but since there is rarely a ‘one size fits all’ solution and the consequences of incorrect dosages and compounds could arguably exacerbate the situation. Significant work is still required to understand what is happening in each tumour so it can be treated accordingly. HDAC5 and HDAC9 were found to be highly expressed at the mRNA level amongst prognostically unfavourable medulloblastoma patients, whereas HDAC4 and HDAC1 were found to be down-regulated [24]. Patients with high expression of both HDAC5 and HDAC9 had a lower survival probability than those who had high HDAC5 or HDAC9 expression. Patients with low HDAC5 and HDAC9 expression had a significantly higher overall survival probability than either of the other groups [24]. These expression patterns also correlate

NEURO-ONCOLOGY SUPPLEMENT

with molecular subgroups, with lower expression in the WNT and SHH groups and higher expression seen in groups C and D [24].

Therapeutic Potential of HDACs for Childhood Brain Tumours HDAC Inhibitors There are multiple types of HDAC inhibitors (HDACi). They have different structural characteristics and inhibit different HDAC isoforms. Some target just one HDAC, some a whole class of HDACs. HDACis can cause cell cycle arrest, differentiation or apoptosis both in vitro and in vivo [25]. The length of time, concentration and type of inhibitor used affects the number of genes detected with altered transcription [26]. It was only recently that the crystal structure of the interaction between HDAC8 and hydroxamate was solved [27] providing a greater understanding of the mechanism of action of HDAC inhibition. In this case, the hydroxamic acid inhibitor directly interacts with the zinc ion at the base of the catalytic pocket of HDAC8 [26]. Richon et al. (2000) showed increased numbers of cells arresting in G1 phase of the cell cycle with low concentrations of the HDACi, suberoylanilide hydroxamic acid (SAHA), with higher concentrations resulting in cells arresting in both G1 and G2 phase and decreased numbers of cells in S phase [28]. This is thought to be due to the induction of p21, one of the first genes to be switched on under HDAC inhibition, inhibiting cyclin dependent kinases (CDKs) which regulate G1 progression and G1/S, G2/M transitions [29]. Glioblastoma Multiforme Although still not used as a standard mode of treatment, there are case reports of various HDAC inhibitors successfully treating, or managing, childhood brain tumours. In 2004 it was reported that a ten year old with a GBM in the pineal gland showed no evidence of tumour response using the German protocol for malignant gliomas in children (HITGBM-C), which included partial surgical resection, radiotherapy and multiple chemotherapies. After 30 weeks, no response and an array of severe therapy-related side effects, treatment

was switched to increasing dosages of Valproic acid (VPA), an HDACi normally used to treat epilepsy in children. After just 14 weeks, the tumour decreased and the child was back in school. Complete remission was seen at 10 months on MRI scans. Unfortunately, the child reduced the dosages due to drowsiness and the tumour relapsed at 16 months from the start of HDACi treatment [30]. Diffuse Intrinsic Pontine Glioma A recent study found twelve out of sixteen DIPG cultures insensitive to traditional chemotherapeutics, demonstrated a concentration dependent decrease in viability and proliferation and increased cell death following treatment with the pan-HDACi, panobinostat [31]. Decreased expression of proliferation associated genes and the oncogene MYC was also observed [31]. Knockdown of HDAC1 or HDAC2 was shown to decrease viability of DIPG cells [31] supporting the notion that inhibition of certain HDACs can be beneficial in the treatment of DIPG. On top of this data, the study showed that the same positive effect happened in a DIPG xenograft mouse model where at just one week there was a significant reduction in tumour growth and treated mice had significantly prolonged survival [31]. Embryonal Brain Tumours Embryonal brain tumours have been shown to have differing levels of sensitivity to HDACis. Proliferation in medulloblastoma cells has been decreased in response to an array of HDACis; Trichostatin A (TSA) and M344 proving most effective [32]. TSA was shown to significantly suppress proliferation in CNS PNET, medulloblastoma, ependymoma, GBM, and mouse neural progenitor cells, with GBM cells being the least responsive [33]. There was increased activation of cleaved caspase 3, a pro-apoptotic protein, and down-regulation of an antiapoptotic protein, Bcl-2, in CNS PNET and medulloblastoma cell lines. At 48 hours of treatment, all cell lines showed a concentration-dependent increase in subG0-G1 phase indicative of apoptosis [31]. Medulloblastoma A 2011 study found that curcumin, derived from the plant Curcuma longa, inhibited HDAC4 and induced medulloblastoma cell death in a time and concentration-

Oncology News | Neuro-oncology supplement 2016 | ÂŠ McDonnell Mackie

dependent manner [25]. Treated cells also show an increase in caspase-3 cleavage and poly (ADP-ribose)polymerase (PARP) suggestive of apoptosis [25]. However, it is not clear if the increase in cleaved caspase-3 and PARP is related to HDAC4 inhibition. Another study on medulloblastoma demonstrated TSA decreased viability and induced apoptosis in cell lines. The HDACi up-regulated 714 genes some of which were involved in varying biological pathways such as angiogenesis, apoptosis, Ras, p53 and Wnt signalling cascades [34]. A tumour suppressor gene in medulloblastoma, DKK1, was found to be significantly down-regulated by 80% in cells but increased when treated with TSA [34]. In support of HDACi-induced cell death in medulloblastoma cells, Sonnemann et al. observed a concentration-dependent increase in cell death of medulloblastoma cell lines with three different HDACi compounds [35]. Caspase-3 and -9 activation and a decrease in mitochondrial transmembrane potential suggest these compounds induce apoptosis in these cell [35]. Interestingly, if treated with concomitant ionizing radiation (IR), HDACis lead to cell death at 46-65% compared with 22% with IR alone [35]. The same theory was then tested with chemotherapeutics, which induced cell death in 29% of cells alone and 76% of cells when treated concomitantly with an HDACi [35]. However, this effect was only seen in some combinations of the drugs and the authors attribute this discrepancy to the difference in the mode of action of the cytotoxic agents.

Concomitant Therapy and Clinical Trials Although many HDAC inhibitors have reached clinical trials for various different cancers, unfortunately there are relatively few involving childhood brain tumours. A phase I trial was, however, conducted with vorinostat in combination with temozolomide for relapsed or refractory primary brain or spinal cord tumours in children [36]. Sixteen of the original nineteen patients were evaluated at the end of the trial, three had stable disease in ependymoma, ganglioglioma and high grade glioma, one patient had a partial response in ependymoma and the rest had progressive disease [36]. No clear relationship was seen between dose and 21

NEURO-ONCOLOGY SUPPLEMENT

response [36]. This may be due to the different types of tumour enrolled in the trial, as discussed earlier, the same treatment is unlikely to have the same effect across a variety of tumours. It is well known that temozolomide is ineffective in paediatric glioblastoma [37] for instance, but can be beneficial in other tumours and it has been discussed earlier; here how different types of HDACi work differently dependent on the tumour type [25,26]. A clinical trail led by the Pediatric Brain Tumour Consortium (Pediatric Brain Tumour Consortium PBTC-047) in America is now starting a Phase I trial treating children with progressive DIPG with 26 courses of panobinostat over 2 years. With the previous in vitro and in vivo success discussed earlier [31], it is hoped the findings translate into the clinic as expected.

Discussion It is clear there are still huge gaps in our knowledge in the mechanistic roles histone deacetylases play in these tumours and the more we discover, the clearer it is that each tumour has it’s own molecular signature that should be treated in a unique way. Since personalised therapy is still a way off, it is hoped that studies such as the ones discussed here, can enhance our understanding and ability to attack these tumours in novel and more effective ways.

REFERENCES 1. Louis DN, Ohgaki H, Wiestler OD, Cavenee WK, Burger PC, Jouvet A, et al. The 2007 WHO classification of tumours of the central nervous system. Acta Neuropathol. 2007 Aug;114(2):97–109.

20. Brody BA, Kinney HC, Kloman AS, Gilles FH. Sequence of central nervous system myelination in human infancy. I. An autopsy study of myelination. J Neuropathol Exp Neurol. 1987 May;46(3):283-301.

2. Vanan MI, Eisenstat DD. Management of high-grade gliomas in the pediatric patient: Past, present, and future. Neuro-Oncology Practice. 2014 Nov 14;1(4):145–57.

21. Kinney HC1, Brody BA, Kloman AS, Gilles FH. Sequence of central nervous system myelination in human infancy. II. Patterns of myelination in autopsied infants. J Neuropathol Exp Neurol. 1988 May;47(3):217-34.

3. Smith MA, Seibel NL, Altekruse SF, Ries LAG, Melbert DL, O'Leary M, et al. Outcomes for Children and Adolescents With Cancer: Challenges for the Twenty-First Century. Journal of Clinical Oncology. 2010 May 18;28(15):2625–34. 4. Barneda-Zahonero B, Parra M. Histone deacetylases and cancer. Molecular Oncology. Elsevier B.V; 2012 Dec 1;6(6):579–89. 5. Haberland M, Montgomery RL, Olson EN. The many roles of histone deacetylases in development and physiology: implications for disease and therapy. Nat Rev Genet. 2009 Jan;10(1):32–42. 6. Lucio-Eterovic AKB, Cortez MAA, Valera ET, Motta FJN, Queiroz RGP, Machado HR, et al. Differential expression of 12 histone deacetylase (HDAC) genes in astrocytomas and normal brain tissue: class II and IV are hypoexpressed in glioblastomas. BMC Cancer. BioMed Central; 2008;8(1):243. 7. Li Z, Zhu WG. Targeting histone deacetylases for cancer therapy: from molecular mechanisms to clinical implications. Int J Biol Sci. 2014;10(7):757–70. 8. Volmar C-H, Wahlestedt C. Histone deacetylases (HDACs) and brain function. Neuroepigenetics. 2015;1:20–7. 9. Ye F, Chen Y, Hoang T, Montgomery RL, Zhao X-H, Bu H, et al. HDAC1 and HDAC2 regulate oligodendrocyte differentiation by disrupting the beta-catenin-TCF interaction. Nat Neurosci. 2009 Jul;12(7):829–38. 10. Montgomery RL, Hsieh J, Barbosa AC, Richardson JA, Olson EN. Histone deacetylases 1 and 2 control the progression of neural precursors to neurons during brain development. Proc Natl Acad Sci USA. National Acad Sciences; 2009 May 12;106(19):7876–81. 11. Castelo-Branco G, Lilja T, Wallenborg K, Falcão AM, Marques SC, Gracias A, et al. Neural stem cell differentiation is dictated by distinct actions of nuclear receptor corepressors and histone deacetylases. Stem Cell Reports. 2014 Sep;3(3):502–15. 12. Kim AH, Puram SV, Bilimoria PM, Ikeuchi Y, Keough S, Wong M, et al. A centrosomal Cdc20-APC pathway controls dendrite morphogenesis in postmitotic neurons. Cell. 2009 Jan 23;136(2):322–36. 13. Sugo N, Oshiro H, Takemura M, Kobayashi T, Kohno Y, Uesaka N, et al. Nucleocytoplasmic translocation of HDAC9 regulates gene expression and dendritic growth in developing cortical neurons. Eur J Neurosci. Blackwell Publishing Ltd; 2010 May;31(9):1521–32. 14. Lai I-L, Lin T-P, Yao Y-L, Lin C-Y, Hsieh M-J, Yang W-M. Histone deacetylase 10 relieves repression on the melanogenic program by maintaining the deacetylation status of repressors. J Biol Chem. American Society for Biochemistry and Molecular Biology; 2010 Mar 5;285(10):7187–96. 15. Marin-Husstege M, Muggironi M, Liu A, CasacciaBonnefil P. Histone deacetylase activity is necessary for oligodendrocyte lineage progression. J Neurosci. 2002 Dec 1;22(23):10333–45. 16. Laeng P, Pitts RL, Lemire AL, Drabik CE, Weiner A, Tang H, et al. The mood stabilizer valproic acid stimulates GABA neurogenesis from rat forebrain stem cells. J Neurochem. 2004 Oct;91(1):238–51. 17. Zong H, Parada LF, Baker SJ. Cell of origin for malignant gliomas and its implication in therapeutic development. Cold Spring Harb Perspect Biol. 2015 Jan 29;7(5). pii: a020610. doi: 10.1101/cshperspect.a020610. Review. 18. Roessmann U, Gambetti P. Astrocytes in the developing human brain. An immunohistochemical study. Acta Neuropathol. 1986;70(3-4):308-13

22. Lebel C1, Gee M, Camicioli R, Wieler M, Martin W, Beaulieu C. Diffusion tensor imaging of white matter tract evolution over the lifespan. Neuroimage. 2012 Mar;60(1):340-52. doi: 10.1016/j. neuroimage.2011.11.094. Epub 2011 Dec 8. 23. Baker SJ, Ellison DW, Gutmann DH. Pediatric gliomas as neurodevelopmental disorders. Glia. 2016 Jun;64(6):879-95. doi: 10.1002/glia.22945. Epub 2015 Dec 6. Review. 24. Milde T, Oehme I, Korshunov A, Kopp-Schneider A, Remke M, Northcott P, et al. HDAC5 and HDAC9 in medulloblastoma: novel markers for risk stratification and role in tumor cell growth. Clin Cancer Res. 2010 Jun;16(12):3240–52. 25. Lee SJ, Krauthauser C, Maduskuie V, Fawcett PT, Olson JM, Rajasekaran SA. Curcumin-induced HDAC inhibition and attenuation of medulloblastoma growth in vitro and in vivo. BMC Cancer. 2011;11:144. 26. Xu WS, Parmigiani RB, Marks PA. Histone deacetylase inhibitors: molecular mechanisms of action. Oncogene. 2007 Aug;26(37):5541–52. 27. Somoza JR, Skene RJ, Katz BA, Mol C, Ho JD, Jennings AJ, et al. Structural snapshots of human HDAC8 provide insights into the class I histone deacetylases. Structure. 2004 Jul;12(7):1325–34. 28. Richon VM, Sandhoff TW, Rifkind RA, Marks PA. Histone deacetylase inhibitor selectively induces p21WAF1 expression and gene-associated histone acetylation. PNAS. National Acad Sciences; 2000 Aug 29;97(18):10014– 9. 29. Vidal A, Koff A. Cell-cycle inhibitors: three families united by a common cause. Gene. 2000 Apr 18;247(1-2):1–15. 30. Witt O, Schweigerer L, Driever PH, Wolff J, Pekrun A. Valproic acid treatment of glioblastoma multiforme in a child. Pediatr Blood Cancer. 2004 Aug;43(2):181. 31. Grasso CS, Tang Y, Truffaux N, Berlow NE, Liu L, Debily MA, et al. Functionally defined therapeutic targets in diffuse intrinsic pontine glioma. Nat Med. 2015 Jul;21(7):827. 32. Furchert SE, Lanvers-Kaminsky C, Juürgens H, Jung M, Loidl A, Frühwald MC. Inhibitors of histone deacetylases as potential therapeutic tools for high-risk embryonal tumors of the nervous system of childhood. Int J Cancer. 2007 Apr;120(8):1787–94. 33. Rahman R, Osteso-Ibanez T, Hirst RA, Levesley J, Kilday JP, Quinn S, et al. Histone deacetylase inhibition attenuates cell growth with associated telomerase inhibition in high-grade childhood brain tumor cells. 2010 Sep;9(9):2568–81. 34. Vibhakar R, Foltz G, Yoon JG, Field L, Lee H, Ryu GY, et al. Dickkopf-1 is an epigenetically silenced candidate tumor suppressor gene in medulloblastoma. Neuro Oncol. 2007 Apr;9(2):135–44. 35. Sonnemann J, Kumar KS, Heesch S, Müller C, Hartwig C, Maass M, et al. Histone deacetylase inhibitors induce cell death and enhance the susceptibility to ionizing radiation, etoposide, and TRAIL in medulloblastoma cells. Int J Oncol. 2006 Mar;28(3):755–66. 36. Hummel TR, Wagner L, Ahern C, Fouladi M, Reid JM, McGovern RM, et al. A pediatric phase 1 trial of vorinostat and temozolomide in relapsed or refractory primary brain or spinal cord tumors: a Children's Oncology Group phase 1 consortium study. Pediatr Blood Cancer. 2013 Sep;60(9):1452–7. 37. Nicholson HS, Kretschmar CS, Krailo M, Bernstein M, Kadota R, Fort D, et al. Phase 2 study of temozolomide in children and adolescents with recurrent central nervous system tumours: a report from the children’s oncology group. Cancer. 2007 Oct;110(7):1542-50.

19. Monje M, Mitra SS, Freret ME, Raveh TB, Kim J, Masek M, et al. Hedgehog-responsive candidate cell of origin for diffuse intrinsic pontine glioma. Proc Natl Acad Sci USA. 2011 Mar;108(11):4453–8.

Free Subscription Have the digital version of Oncology News delivered to your inbox every two months by signing up for a FREE subscription at www.oncologynews.biz

You can also browse and search the back catalogue and read or download the various articles in PDF form

Bookmark us today! www.oncologynews.biz

gliolan® 30 mg/ml powder for oral solution. Qualitative and quantitative composition: One vial contains 1.17 g of 5 aminolevulinic acid (5-ALA), corresponding to 1.5 g 5 aminolevulinic acid hydrochloride (5 ALA HCl). One ml of reconstituted solution contains 23.4 mg of 5 aminolevulinic acid, corresponding to 30 mg 5 aminolevulinic acid hydrochloride (5 ALA HCl). Therapeutic indications: gliolan is indicated in adult patients for visualisation of malignant tissue during surgery for malignant glioma (WHO grade III and IV). Posology and method of administration: This medicinal product should only be used by experienced neurosurgeons conversant with surgery of malignant glioma and in-depth knowledge of functional brain anatomy who have completed a training course in fluorescence-guided surgery. The recommended dose is 20 mg 5 ALA HCl per kilogram body weight. Contraindications: Hypersensitivity to the active substance or porphyrins; acute or chronic types of porphyria; pregnancy. Undesirable effects: Adverse reactions observed after the use for fluorescence-guided glioma resection are divided into the following two categories: Immediate reactions occurring after oral administration of the medicinal product before anaesthesia (= active substancespecific side effects); combined effects of 5 ALA, anaesthesia and tumour resection (= procedure-specific side effects). Substance-specific side effects: Uncommon: Hypotension; nausea, photosensitivity reaction, photodermatosis. Substance-specific side effects: Uncommon: Hypotension; nausea, photosensitivity reaction, photodermatosis. Procedure-related side effects: The extent and frequency of procedurerelated neurological side effects depend on the localisation of the brain tumour and the degree of resection of tumour tissue lying in eloquent brain areas. Very common: Anaemia, thrombocytopenia, leukocytosis. Blood bilirubin, alanine aminotransferase, aspartate aminotransferase, gamma glutamyltransferase or blood amylase increased. Common: Neurological disorders (e.g. hemiparesis, aphasia, convulsions, hemianopsia). Thromboembolism. Vomiting, nausea. Uncommon: Brain oedema, hypotension. Very rare: Hypesthesia; diarrhoea. One case of moderate chills; one respiratory insufficiency after overdose, which resolved completely. Legal classification: POM (prescription only medicine). Price per vial: €980/ £ 950 ex. factory. Marketing authorisation number: EU/1/07/413/001-003. Marketing authorisation holder: medac GmbH, Theaterstraße 6; D-22880 Wedel. Date of revision of text: 02/2014. gliolan has been authorised in all countries of the EU as well as in Iceland, Norway, Israel and Taiwan. Adverse events should be reported. Reporting forms and information can be found at www.mhra.gov.uk/ yellowcard. Adverse events should also be reported to medac drug safety at: drugsafety@medac.de medac code: medacuk 021/04/2016 Date of Preparation: April 2016

Give her the best chance

fluorescence-guided resection

Gliolan, for the visualisation of malignant tissue during surgery for malignant glioma (WHO grade III and IV) in adult patients.

seeing is the beginning