234b Oncogenes Flashcards Preview

heme/onc > 234b Oncogenes > Flashcards

Flashcards in 234b Oncogenes Deck (18):
1

oncogene overview? characteristics? one or both alleles for cancer?

gain of function via mutation or over-expression (via mutation in regulatory DNA)-> increased cancer risk

immortalized (rebuilds telomeres)
grows in serum-free conditions (doesn't need growth factors)

need damage to only 1 allele (dominant)

2

BCR-ABL
associated tumor?
mechanism?
gene product?
drug that blocks?

CML, ALL (leukemia)

fusion of two proteins that results in overactivation --> abl kinase added on to Bcr (9:22 fusion - Philadelphia chromosome)

tyrosine kinase

imatinib - binds ATP binding site on Bcr-Abl

3

bcl-2
associated tumor?
gene product?

follicular and undifferentiated lymphomas

anti-apoptotic molecule (inhibits apoptosis)

4

BRAF
associated tumor?
gene product?

melanoma

serine/threonine kinase

5

c-kit
associated tumor?
gene product?

GI stromal tumor (GIST)

cytokine receptor (for stem cell factor)

6

c-myc
associated tumor?
gene product?

burkitt lymphoma

transcription factor -- point mutation --> impaired degradation

7

HER2/neu (c-erbB2)
associated tumor?
mechanism?
gene product?
drug?

breast, ovarian, gastric carcinomas

amplified receptor expression

tyrosine kinase receptor

trastuzumab

8

L-myc
associated tumor?
gene product?

Lung tumor (L)

transcription factor

9

N-myc
associated tumor?
gene product?

Neuroblastoma (N)

transcription factor

10

ras
associated tumor?
normal regulation?
normal function?
gene product of ras?

colon cancer, lung cancer, pancreatic cancer

regulated by GTP-binding and hydrolysis via GAP (turns off) with GDP and GEF (turns on) with GTP

activates down stream events after receptor tyrosine kinase binds signaling molecule --> turns on MAP kinase pathway, proliferation, protein synthesis AKA activates many pathways)

GTPase --> allows ras to be activated without receptor tyrosine kinase pathway

11

ret
associated tumor?
gene product?

MEN 2A and 2B

tyrosine kinase

12

typical signaling transduction pathway and examples

1) growth factor

2) GF receptors (EGFR, Her2)

3) Signal transduction proteins (GTPase - Ras, tyrosine kinase - Abl, Src, serine-threonine kinase-PI3K)

4) transcription factor (Myc)

5) cell cylin control (cyclins)

6) regulators of apoptosis (Bcl2)

13

what transfers a phosphate group from ATP to an amino acid side chain? what removes it?

protein kinase

protein phosphaTase (Takes away P)

14

PI3K (PI3 kinase) pathway

lipid kinase that P Akt -->

increase proliferation, promotes cell growth (protein synthesis), and inhibits apoptosis

14

PI3K (PI3 kinase) pathway

lipid kinase that P Akt -->

increase proliferation, promotes cell growth (protein synthesis), and inhibits apoptosis

15

Myc basic fxn

transcription factor that regulates a subset of genes that control cell proliferation and growth (cyclin, Rb, E2F)

15

Myc basic fxn

transcription factor that regulates a subset of genes that control cell proliferation

16

VEGF
cancer?
drug?

breast, colorectal, kidney

bevacizumab