B/08 Flashcards
What is the role of RB gene?
block the cell cycle in G1 phase when it is NOT phosphorylated
How does RB block the cell cycle?
by sequestering E2F factor
Which enzymes phosphorylate RB when there is need for cell division? (2)
- CDK4,6
- cyclin D
Hereditary neoplasms caused by RB mutation? (2)
- retinoblastoma
- osteosarcoma
Sporadic neoplasms caused by RB mutation? (3)
- retinoblastoma
- breast cancer
- colon cancer
Role of p53?
- stops cell cycle and proliferation
- starts DNA repair
- triggers apoptosis
What happens when there is mutation of the p53 gene?
no more inhibition of CDKI p21, so no inhibition of CDK4,6/CD complex
Hereditary neoplasm caused by p53 mutation?
Li-fraumeni syndrome
Sporadic neoplasms caused by p53 mutations?
most human cancers
What does APC gene do?
inhibits cell proliferation
How does APC inhibit cell proliferation?
degrades beta-catenin when WNT isn’t present
What happens when there is APC mutation?
No more inactivation of cell proliferation because no degradation of beta-catenin
Hereditary neoplasms caused by APC mutation?
Familial adenomatous polyposis, Melanoma
Sporadic neoplasms caused by APC mutation? (3)
- colon carcinoma
- stomach carcinoma
- pancreas carcinoma
