W07_03 Molecular pathogenesis of cancer - common genes

Question 1

what kinds of mutations are there in cancer?

Answer 1

point;
insertion/deletion;
amplification/copy number alteration;
translocation/chromosomal rearrangement

Question 2

define oncogene

Answer 2

promotes autonomous growth in cancer cells, in the absence of cell growth-promoting signals

Question 3

define proto-oncogene

Answer 3

non-mutated, “normal” gene with the potential to become oncogenic.

Question 4

define oncoprotein

Answer 4

the product of an oncogene

Question 5

typically, oncoproteins can be of these signalling types

Answer 5

growth factors;
growth factor receptors;
signal transduction molecules;
nuclear regulatory proteins;
cell cycle regulators

Question 6

what class of signalling is Her2-neu?

Answer 6

growth factor receptor

Question 7

what happens to Her2-neu in cancer?

Answer 7

gene is amplified, and the receptor is increased as a result

Question 8

what’s the clinical significance of a Her2-neu mutation?

Answer 8

gives rise to breast cancer;

25-30% of breast cancers express this on the surface

Question 9

treatment for Her2-neu+ breast cancer?

Answer 9

trastuzumab (Herceptin) targeted therapy

Question 10

what class of signalling is Ret?

Answer 10

growth factor receptor (normally a glial-derived neurotrophic factor receptor)

Question 11

when is ret normally expressed?

Answer 11

during neural development, and also in neuroendocrine cells

Question 12

where is ret normally expressed?

Answer 12

C-cells of thyroid, adrenal medulla, parathyroid cells

Question 13

which clinical diseases are caused by ret mutation (usually germ-line mutation)?

Answer 13

multiple endocrine neoplasia type ii,

familial medullary thyroid cancer

Question 14

what class of signalling is Ras?

Answer 14

receptor-associated signal transduction molecule

Question 15

what are the three most well known Ras oncogene types?

Answer 15

HRas,
KRas,
NRas

Question 16

how can Ras become problematic?

Answer 16

if the pathway of GTPase is blocked, then Ras will stay constitutively active

Question 17

ras helps us guide treatment for which type of cancer?

Answer 17

lung

Question 18

what class of signalling is Abl?

Answer 18

non-receptor associated tyrosine kinase

Question 19

what mutation leads to a problem with abl?

Answer 19

when abl translocates onto chromosome 22 and makes bcr-abl

Question 20

what disease results from bcr-abl?

Answer 20

cml and all

chronic myeloid leukemia and acute lymphoblastic leukemia

Question 21

therapy for bcr-abl?

Answer 21

imatinib mesylate

Question 22

what class of signalling is Myc?

Answer 22

nuclear regulatory protein

Question 23

how can myc go wrong?

Answer 23

thru amplification or translocation

Question 24

n-myc is amplified to in which cancer?

Answer 24

neuroblastoma

Question 25

l-myc is amplified in which cancer?

Answer 25

SCLC

Question 26

what’s a “double minute”?

Answer 26

copies of a gene that float around, independent of a chromosome

Question 27

what’s the molecular cause of burkitt’s lymphoma?

Answer 27

translocation of the myc gene to the IgH gene

Question 28

what class of signalling is cyclin D?

Answer 28

cell cycle regulator

Question 29

cyclin D associates with which two factors to help cell cycle regulation?

Answer 29

CDK4 and CDK6