Oncology/Genetics Flashcards
Cetuximab:
- Mechanism of action
- What patients is the use restricted too
- What other mutations in bowel cancer are identified but do not predict response to cetuximab in metastatic bowel cancer?
- Monoclonal antibody which inhibits epidermal growth factor receptors
- Wild type (non-mutated KRAS
- APC, MSH2, SMAD4, MYC
What is cytokinesis
Division of cellular cytokine to two daughter cells
Describe the Wnt pathway
Signalling pathway that plays an important role in intestinal epithelial cell proliferation
Activation causes translocation of beta-carotene in the nucleus where it regulates the expression of target genes
What leads to sporadic, microsatellite unstable colon cancer?
CpG island hypermethylation which causes silencing of the MLH1 gene
What is the mutation associated with HNPCC (Lynch syndrome)
Feeling mutation of MLH1 (MSH2)
Describe the mutation in Cowden syndrome
PTEN gene
Mutations in juvenile polyposis
SMAD4 + BMPR1A
Describe mutation in hereditary diffuse gastric cancer
CDH1 - cause loss of e-cadherin needed for cell adhesion which allows epithelial tumour cells to invade basement membrane and metastasise
Mutation in Peutz-Jeghers
STK11, LKB1
What type of cancer does VHL has a role in?
RENAL cancer
No role in colon cancer
Describe what a nonsense mutation is
It results in a premature stop codon
Describe a missence mutation
Point mutation in which a single nucleotide change results in a change in amino acid encoded by the codon
Describe the cell cycle
G1 (initial growth phase) > S (duplication of genome) > G2 (2nd growth phase in preparation for cell division > M (mitosis; divide into daughter cells) > GO(quiescent phase)
What is senescence?
Process by which cells permanently lose their ability to divide
Prevents excess proliferation
Lost during carcinogenesis
