Cancerous cells Flashcards
1
Q
Cancer is a result of degradation of the regulatory mechanisms of the cell cycle. Which two regulatory genes must be affected?
A
Tumour suppression gene - P53 & Oncogene - RAS
2
Q
What does P53 (tumour suppression gene) do?
A
P53 recognises & repairs DNA damage at the G1 checkpoint by stopping growth and potentially triggering apoptosis. If P53 is damaged or mutated, damaged DNA remains unfixed and the damaged cells continue to divide. This results in all cells containing the genetic error & cancer may develop.
3
Q
What does RAS (oncogene) do?
A
Oncogene - RAS stimulates cell division & cannot be deactivated once activated. In cancerous cells, the RAS gene is locked into its binding shape, requiring no signal at the receptor to promote cell division.
