Mutations And Cancer

Front 1

5 Characteristics of Cancer in vivo

Back 1

1) loss of growth control
2)resistance to apop
3)invade tissues
4)autocrine growth/angiogenesis
5)can metastasize

Front 2

cancer cells in vitro

Back 2

1)reduced serum requirement
2) attachment to matrix not required
3) grow right on top of each other=loss of contact inhibition
4) loss of density-dependent growth inhibition

Front 3

In order for a proto-oncogene to proliferate, there has to be _________ in a cell

Back 3

multiple mutations

Front 4

we have a high risk for cancer as we age because....

Back 4

we accumulate mutations over time

Front 5

What are proto-oncogenes? name 3

Back 5

genes that code for function of cell growth. a ONCOGENE is a proto-oncogene that has been turned permanently ON via a gain of function mutation. mutation is dominant b/c one copy producese phenotype.


Ras, abl, myc

Front 6

Mutation in Ras=>cancer how?

Back 6

mutation inhibits GTPase activity of Ras=unable to go to inactive phase=constantly ON and phosphorylating MAPK (ERK)->G1 and S cycles

Front 7

abl and myc oncogenes involve what?

Back 7

translocations between chomosomes that cause constant activation (abl) and over-expression (myc) of genes

Front 8

What is gene amplification? what kind of tumors is it present in?

Back 8

cancer cells amplify their DNA so that there are multiple copies of the same gene in the same cancer cell

present in breast, ovarian, and lung cancers

Front 9

Gain of function mutations in proto-oncogenes cause

Back 9

loss of cell cycle regulation and uncontrolled proliferation

Front 10

Tumor Suppressor genes do what?

name 3 tumor suppressor genes

Back 10

inhibit cell proliferation

Rb, p16, p53

Front 11

Function of gene product of Rb

Back 11

Rb binds to E2F transcription factor and inhibits it's activty=G1 arrest

Front 12

Function of gene product of p16

Back 12

INK4 family of CKI=Inhibits CDK4 and CDK6=G1 arrest

Front 13

p53

Back 13

"guardian angel", transcription factor that induced by DNA damage

-activates transcription of p21 gene+many other genes that arrest cell cycle=G1 and S arrest

Front 14

Loss of function mutations must inactivate ______ of the suppressor genes to cause tumor development

Describe familial retinoblastoma and Sporadic retinoblastoma

Back 14

BOTH COPIES. 2 nonfuctional alleles needed for cancer to proliferate


familial=Rb gene is inherited=1 Bad and 1 Mutated=transformation

sporadic (non inherited)= 2 mutate. Both Rb genes turn bad->transformation

Front 15

p16 is in the INK family which are...?

what does p16 inhibit?

blocks which cell cycle phase? how?

Back 15

cyclin-dependent kinase inhibitors (CKI)

inhibits CDK4, CDK6/Cyclin D

blocks G1 phase via binding to the Cyclin D/CDK6 complex=>inactive

Front 16

p53 is a _____ element that activates the ____ gene. This gene then expresses a protein that inhibits _____, leading to ____ and ____ phase arrest.

Back 16

trans element, that activates the p21 gene. This gene then expresses a protein that inhibits Cyclin E and CDK2, leading to G1 and S Arrest.

Front 17

High frequency of p53 mutations occur in the _____domain

Back 17

DNA binding domain

-p53 function is lost in almost all cancers

Front 18

NF-1 is a _______ gene that codes for the GTPase that _______.

Back 18

tumor suppressor gene that codes for the GTPase that inactivates Ras.