Oncolytic Viruses in Cancer Treatment by Annabelle Shilling (IV) Vaccines have been used to prevent cancer-causing infections such as HPV, but their applications within cancer research extend further than that. While virtually every vaccine in history has been wielded to prevent the acquisition of some infectious disease, oncolytic virotherapy is a novel branch of oncology pertaining to vaccines used not to prevent an infectious disease, but designed to cure a noninfectious one. An oncolytic virus is one that seeks and destroys exclusively tumor cells. It typically does so by lysing such cells, but this direct cytoreduction is not the only effect of these viruses. A helpful byproduct of the infection is the stimulation of the immune system within the tumor microenvironment. While the viruses go about lysing tumor cells, the tuOncolytic virus particle by Lleyton Lance (VI) mor antigens released induce both an innate and an adaptive immune response (ex. increasing tumor T-Cell counts), the latter of cle arrest after becoming infected with it. With which functions as a lasting immunotherapy. adenoviruses, quiescent cells can be pushed into S phase by E1A proteins after they bind to Oncolytic viruses can be lab-made or naturally retinoblastoma proteins within the cell. These occuring; the former of which ensures the viruses Rb proteins are used to regulate the transition must depend on tumor cells for replication and from G1 to S phase through interactions with its establishment of tumor-specific alterations E2F transcription factors, and the Rb binding for lysis. The Onyx-015 Adenovirus was one of to E1A subsequently causes the release of E2F. the first oncolytic viruses used in clinical trials, E1A, undesirably, causes p14ARF to be released and in spite of its benefit proving slightly unas well, a protein that inhibits Mdm2 (Murine derwhelming, the trials did confirm two things: double minute 2) from degrading p53. The tranoncolytic viruses are safe to be administered scription factor p53 is used to initiate cell cycle to humans and they hold the potential to work arrest or apoptosis as a consequence of signals in conjunction with systemic radiotherapy and revealing damage to DNA—it can also do this chemotherapy as a combined cancer treatment. due to cellular stress. However, if p53 accumulates due to the lack of degradation, the cell cyOnyx-015 is selective, not in the sense that cle arrest or apoptosis that can occur is detriit will not infect healthy cells, but that only mental to the viral life cycle—if the cell dies or healthy cells will undergo apoptosis or cell cyceases growth before the viral cycle is complete,
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