Tumour suppressor genes
Genes that inhibit expression of the
tumourigenic phenotype. They are normally involved in holding
cellular growth in check. When tumour suppressor genes are
inactivated or lost, a barrier to normal proliferation is removed and
unregulated growth is possible24.
A tumour suppressor gene directs the production of a protein that is part of the system that regulates cell division. The tumour suppressor protein plays a role in keeping cell division in check. When mutated, a tumour suppressor gene is unable to do its job, and as a result uncontrolled cell growth may occur. This may contribute to the development of a cancer24.
Within our genome is a class of genes called tumour suppressor genes. These genes make proteins that act like brakes within the cell, and when they're turned on they actually prevent the cell from dividing. However, if a tumour suppressor gene is lost or mutated in a very specific way so that it loses its activity, the cell can then start to divide uncontrollably, and this contributes to the development of cancer. So the inactivation of tumour suppressor genes is one type of genetic alteration that contributes to tumour genesis. "Tumour genesis" is the technical term for the development of cancer24.
