FEATURE
Entropy and Cancer Development - Disorder in the Building Blocks of Life Alex Blain Every cell within your body contains the instructions for life in the form of DNA molecules made up of thousands of genes which instruct your body to make proteins. When your cells divide, your DNA must be replicated in order for the two resultant cells to have the correct amount of DNA. Replication is very tightly regulated through multiple complex processes. We can liken the normal DNA replication within a cell to the ice state of water, there is a definite structure therefore the amount of disorder and entropy is low. While the accuracy of replication is high, as you age your cells undergo multiple rounds of replication, and errors in DNA known as mutations can occur. Occasionally, these mutations can lead to the uncontrolled division of cells - this is cancer.
fails, a tumour can develop
cells. There are also genes that work as regulatory mechanisms within cells, which control cell division and prevent cancer from arising, these are known as tumour suppressor genes (TSG). As you have two copies of every gene (one from your father and one from your mother), it requires two mutations or “hits” to fully inhibit a TSG function. An example of a TSG is the TP53 gene, this makes a protein named P53 which is referred to as “the guardian of the genome”. P53 becomes activated in response to abnormal signals in the cell and triggers a self-destruct mechanism known as apoptosis. When both copies of TP53 become mutated more mutations can occur within the cell, allowing it to become cancerous. This single cancer cell can be likened to the liquid water, as the genes within the cell have been altered leading to a breakdown in regulation of cell signalling, disorder has increased but is still contained within a single cell.
When a mutation occurs it can affect the function of the protein produced by that gene. There are genes that when mutated can work to promote cancer, these are known as oncogenes and make proteins that are involved in driving the division of
At this stage the cancer cell is usually recognised by the immune system, as specialised cells circle through the body looking for infected or abnormal cells. When the immune cells recognise oddlooking cells, they attack and kill the abnormal cells as a defence mechanism to
When immunosurveillance
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{react} Issue 13 2020
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