Page Contents
OVERVIEW
This page is dedicated to compiling Step 1 study notes for the topic of cancer genetics. This page is likely disorganized as it was made in haste.
IMPORTANT GENES FOR CANCER: PROTO-ONCOGENES
KRAS
IMPORTANT GENES FOR CANCER: TUMOR SUPRESSORS
Retinoblastoma (Rb):
Is a nuclear phosphoprotein that regulates the G1 → S checkpoint of the cell cycle. Hyperphosphorylation of this protein inactivates it, which allows for cells to go past this checkpoint. In its hypophosphorylated state it is active and blocks this progression.
GENERAL PATHWAY FOR COLON CANCER MUTATIONS
1.) APC inactivation:
This gene is a tumor suppressor. The inactivation leads to increased beta-catenin accumulation and uncontrolled cell proliferation.
2.) K-ras activation:
This is a protooncogene. Its activation futhrte leads to unregulated cell growth.
3.) p53 inactivation:
This is a tumor suppressor gene. It triggers apoptosis of cells int eh presence of damaged DNA. Its mutation allows cells with genomic error to enter the cell cycle. It is the last “step” in the formation of this colonic malignancy.
Page Updated: 04.26.2017