What are proto-oncogenes?
Proto-oncogenes are normal genes that code mainly for proteins that control normal cell growth. If mutated, these ``pre-'' cancer genes (proto-) become cancer (onco-) genes.
What are oncogenes?
Oncogenes are abnormal genes that lead to the development of cancer by instructing cells to grow and divide excessively. Think of it as ``stepping on a cell's gas pedal.''
Note: Oncogenes are mutant forms of proto-oncogenes.
What are tumor-suppressor genes?
Tumor-suppressor genes are normal genes found in cells that prevent or inhibit cancerous processes. When mutated or deleted they can lead to cancer, i.e. tumor-suppressor genes are the ``cell's brake pedals.''
What is the most studied tumor-suppressor gene?
What does p53 do in normal, non-cancerous cells?
Note: Tumor-suppressor cells are GOOD. They``suppress'' uncontrollable growth by triggering cell death. Therefore, if p53, for example, is damaged, it will not be able to trigger cell death and the cell will continue to grow on, and on, and on.