Genetic changes in cancer / Molecular oncology

Question 1

what is the genetic basis for cancer development?

Answer 1

inherited/somatic mutations in genes controlling cell death/apoptosis (mutations that activate oncogenes/inactivate tumor suppressor genes)

Question 2

oncogenes

Answer 2

genes promoting cancer development (gain of function)

Question 3

tumor suppressor genes

Answer 3

inhibit cancer development (loss of function)

Question 4

what is the philadelphia chromosome?

Answer 4

fusion protein (heavy chain proteins), c-abl: tyrosine kinase: signal transmission/growth control, primary genetic lesion causes cancer (B-cell tumor)

Question 5

primary tumor

Answer 5

a tumor at the original site where it first arose

Question 6

invasion

Answer 6

direct extension and penetration by cancer cells into neighboring tissues

Question 7

metastasis

Answer 7

spread of cancer cells through the circulatory system or the lymphatic system to more distant locations

Question 8

angiogenesis in tumor development

Answer 8

formation of new blood vessels (required for the growth of a solid tumor)

Question 9

why is it so difficult to cure tumors with chemotherapy?

Answer 9

• heterogenity between patients and tumor cells

- darwin selection on cellular level, relapses common (lower response to treatment)

Question 10

name the hallmarks of cancer by Hanahan and Weinberg

Answer 10

• evading growth suppression
• avoiding immune detection
• enabling reproductive immortality
• tumor promoting inflammation
• deregulation of cellular metabolism
• activation of invasion and metastasis
• inducing angiogenesis
• genome instability
• resisting cell death/apoptosis
• sustained proliferative signaling (RTKs)

Question 11

what can the hallmarks of cancer be utilized for?

Answer 11

as therapeutic targets

Question 12

principal difference between classical chemotherapy and targeted therapy?

Answer 12

chemotherapeutics target all dividing cells (cytotoxic, non-specific), targeted therapies aim to specifically inhibit dysregulated targets in the cancer cells

Question 13

name examples of targeted therapy groups

Answer 13

Kinasei, PARPi, BETi, HDACi

Question 14

describe an example of a tumor suppressor gene

Answer 14

p53: conserves cell stability, activates DNA repair, cell cycle arrest, apoptosis

Question 15

where is p53 dysfunction involved?

Answer 15

colon, lung, breast cancers

Question 16

give an example of a drug that inhibits tumor angiogenesis

Answer 16

VEGF-A (bevacizumab, Avastin)