Cancer is a biological mistake of our body. Let me be more specific. As you know, every cell in our body contains DNA, that needs to be replicated every time the cells multiply.
DNA replication is not an error-free process. Sometimes, during DNA replication, a cell swaps a nucleotide for another, by mistake, converting the original word “CAC” in “CTC”, for example. This simple change of letter modifies the meaning of the string of DNA, therefore altering the protein that this string of DNA will instruct to produce (see previous post: How does DNA make proteins?)
Luckily, most of the times, the cell is able to correct the mistakes!
However, if the DNA is badly damaged and cannot be corrected, the cell will start a process called apoptosis. Apoptosis is a fancy word that refers to a cellular suicidal. Damaged cells go into apoptosis to avoid damaging the rest of the body.
Unfortunately, when the “spelling mistakes” appear in crucial stretches of DNA, that are in charge of controlling the quality of the DNA itself, the errors can be overlooked and therefore not corrected. Moreover, when the errors go undetected the cell is not directed to start the process of apoptosis.
If this happens, we are left with one cell that carries a “spelling mistakes” in a crucial stretch of DNA and that is not going to undergo cellular suicidal. This cell is very likely to become a cancer cell.
Cancer cells have lost nearly any kind of control: they multiply very fast and grow anywhere they can, especially where they should not. They are stronger than healthy cells because they proliferate faster and they do not follow the rules.
Imagine a two-way road, cars stick to their right so whoever drives north follows other cars going north and the same holds for whoever is heading south: no traffic-jams, no accidents. But what if a car starts driving on the left-hand side instead?
BOOM!!!!
In this case accidents happen and the road needs to be closed, impeding the normal flow of traffic and causing a lot of issues for the drivers.
This is what happens with cancer cells, they sit in places where they should not and they multiply disproportionately thereby causing severe malfunctioning of our body. Moreover, cancer cells are not good for any job, they are not functional, useless. They just bother those healthy cells that are trying to do their job.
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