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Tumor Suppressor Gene

​Tumor Suppressor Gene

updated: July 17, 2024


A tumor suppressor gene encodes a protein that acts to regulate cell division, keeping it in check. When a tumor suppressor gene is inactivated by a mutation, the protein it encodes is not produced or does not function properly, and as a result, uncontrolled cell division may occur. Such mutations may contribute to the development of a cancer.



Tumor Suppressor Gene. Tumor suppressor genes are present in all cells in our body. When they are switched on, they prevent ourselves from growing and dividing. You can think of them as being like the brakes of a car. However, when a tumor suppressor gene is switched off, either because the cell mistakenly deletes it or mutates it, the brake is released and the cell may start to grow and divide uncontrollably and potentially drive the cell to turn into a cancer cell.

Daphne Bell
Daphne W. Bell, Ph.D.

Senior Investigator

Cancer Genetics and Comparative Genomics Branch