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Flashcards in Cancer Deck (56):
1

cause of cancer is usually traced back to a mutation in what 3 classes

proto-oncogenes
tumor suppressors
caretaker genes

2

proto-oncogenes

control of cell division

3

caretaker gene function

protect integrity of genome

4

6 acquired capabilities of cancer cells

self-sufficiency in growth signals
insensitivity ot antigrowth signals
evade apoptosis
limitless repolicative potential
sustained angiogensis
tissue invasion/metasis

5

ErbB1/HER1

receptor for epidermal growth factor

6

function of erbB1 and HER2

protooncogenes

7

what happens in the mutation that makes ErbB1 an oncogene

gives signal to grow without an appropriate sitmulus

8

what happens in the muation that makes HER2 an oncogene

point mutation, allows receptor dimerization and autophosphorylation in avsence of ligand

9

oncogenic forms of Ras behave inw aht manner

dominant

10

what cancers are mutations in Ras assocaited with

pancreus, large intestine, biliary tract, skin

11

what class are c-fos adn c-myc

protooncogenes

12

what auses burkitt's lumphoma

inppropriate Mc activity

13

what transloation happens in burkitt's lymphoma

chormosome 8 to 14

14

what tends to need to happen for a tumor suppressor gene to be inhbiited

damage to both allels of the gene (recessive)

15

what tends to need to happen for a proto-oncogene to be inhibited

damage to one allele (dominant)

16

Rb function

inhbit cell cycle progession

17

what forms are there of retinoblastoma

hereditary and sporadic

18

retinoblastoma is an example of what phenomon

two hit

19

muations in RB1 are assocaited with what kinds of cancers

osteosarcoma
small cell lung
breast

20

why is p53 usually unstable

assocaited with Mdm2, an E3 ubiquitin ligase

21

what happens when p53 is phosphorylated by ATM/ATR

displacement of Mdm2, making p53 more stable

22

what is the gene that iencodes p53

TP53

23

if DNA damage can't be repaired what does p53 do

signals apoptosis

24

what is the active form of p53

homotetramer

25

what happens if you have a missense muation in a single TP53 allel

produces an inactive protein taht reduces p53 activity within the cell

26

oncogenic p53 mutations act as what

dominant negative muation

27

li-fraumeni syndrome is assocaited with waht kinds of cancers

breast, sarcoma, brain

28

how do you get li-fraumeni syndrome

inherent a muatnt TP53 allel

29

what does E6 inhbiit

p53

30

what does E7 inhibit

Rb

31

NF-1 follows what mechanisms

2-hit

32

BRCA1-BRCA2 are part of what class

caretaker genes

33

function of BRCA1/BRCA2

repair of double-stranded DNA breaks

34

how can increased methylation affect genes

silences

35

how can loss of methylation affect genes

overproduction

36

what happens if you have damge to checkpoint mechanisms and teh shortened chromosomes lack telomere sequences

you get breakage/fusion/bridge cycles and chromosomal instability

37

what happens if you lack telomeres

fusion of sister chromatids at mitosis, get a chromsome with 2 centromeres

38

waht transcription factor does hypoxia trigger

HIF-1alphabeta

39

what happens with HIF-1alpha pairs with HIF0-beta

activat VEGF

40

what does VEGF do

stimualte growth of new blood cessels

41

function of matrix metalloproteases

break down basement membrane

42

fucntino of E cadherin

hold epithelial cells tightly together

43

what happens when you get degration of collagen IV and laminin

stimulate migration

44

symptom of FAP

get thousands to benign polyps in their colon during young age. eventuallly will get colorectal adenocarcomia

45

how do you get RAF

muation of APC

46

function of APC

downregulate growth promoting signals.

47

what happens when you ahve a muajtion that impairs APC function

constitutively active WNT pathway

48

what happens in absense of WNT signals

formation of destruction complex

49

what happens when WNT binds to recpetor

b catenin not destroyed, free beta catenin transolates into nucleus, promotes cellular proliferation

50

HNPCC symptom

cancers of colon, stomach, small intestine

51

HNPCC is assocaited with what genes

MSH2, MLH1

52

function of MSH2

identify DNA containing mismatch errors

53

function of MLH1

helps repair damaged DNA

54

what happens when you get defected NSH2/MLH1

muations accumulate in microsatellite repeasts

55

what is the transloation that heppns in philadelphia chromosome

chromosomes 9 and 22

56

what happens when chromsones 9 and 22 are translocated

fusion of BCR adn ABL1