Oncogenes 3

Question 1

Acquired Capabilities of Cancer and examples

Answer 1

1. Self-sufficiency in growth signals 
Eg. activation of H-Ras (oncogene)
2. Insensitivity to antigrowth signals 
Eg. loss of Rb (tumor suppressor)
3. Evading apoptosis
Eg. expression of surviving factors (IGF-1)
4. Limitless replicative potential
Eg. activation of telomerase
5. Sustained angiogenesis
Eg. expression of VEGF
6. Tissue invasion and metastasis
Eg. inactivation of E-cadherin

Question 2

All anticancer drugs:

Answer 2

1. Mainly cytotoxic
2. Non-selective for cancer cells
3. Very strong side-effects

Question 3

Personalized cancer therapy:

Answer 3

1. Tumors from stem cells are heterogenous and have increased metastatic potential
2. Tumors from late progenitor cells are homogenous and have less metastatic potential.

Question 4

What is the result of treatment?

Answer 4

1. Therapy is effective against cancer stem cells and the tumor is eliminated.
2. The tumor is initially shrunken but the self-renewing CSCs regenerate the tumor.