Cancer is the term used for a set of genetic and multifactorial diseases, that is, several causes contribute to their emergence.
Thus, the main characteristics that influence the transformation of tumor cells are: self-sufficiency in growth signals, resistance to developmental inhibitors, escape from apoptosis, constant replication, formation of angiogenesis, ability to invade and metastasize.
For a normal cell to become a tumor, some transformations are necessary. Thus, the disease is conceptualized as a disordered proliferation of modified cells incapable of responding to the mechanisms of cell growth control.
Some malignant cells have pathways to prevent them from being identified by the immune system as unfit for the body, preventing them from undergoing apoptosis and thus being able to spread.
One of the defense mechanisms that prevent its elimination is the mimicry of normal cells through the expression of checkpoint proteins (checkpoint).
These proteins are cell surface molecules that signal circulating T cells that the cell is normal and should not be eliminated.
In this way, cancers present dedifferentiation or anaplasia, where a reversal in the level of differentiation occurs, causing the tumor cell to lose function. Furthermore, they are known to have the ability to originate anywhere in the body, as a consequence having the chance to invade neighboring cells and/or spread to other organs, due to numerous somatic DNA changes.
Most DNA changes in cancers occur in their genetic sequence and can be called genetically unstable cancers. This instability may be due to random errors in replication, defects in DNA repair or the effect of exposure to agents called carcinogens, which act by initiating or stimulating tumor formation, in addition to causing epigenetic changes.