Lecture 13,14+ Textbook chap 19

Question 1

Sarcomas

percentage+what it is

Answer 1

• rare, less than 2%
• solid tumors of connective tissues (eg: bones, cartilage+fibrous tissues)

Question 2

Leukemias and lymphomas

percentage+what it is

Answer 2

• 8% of human cancers
• arise from blood forming cells+cells of immune system repectively

Question 3

Carcinomas

percentage+what it is

Answer 3

• 90% of human cancers
• originate from epithelial cells

Question 4

Viruses can transform cells (cause cancer) becayse they

Answer 4

carry genes whose protein products interfere with the cells growth regulating activities (oncogenes)

Question 5

Genectic defects arise mostly from

Answer 5

somatic mutations during affected individual’s lifetime, not inherited

Question 6

contact inhibition normal and cancer cells:

Answer 6

• normal cell the inhibition of cell division when they contact a neighbouring cell, they cannot move over one another so they form monolayer on the bottom of dish
• tumour cells have lost contact inhibition

Question 7

Anchorage independence

Answer 7

• cancer cells can grow when suspended in soft agar (independently of a solid surface)
• normal cells need ECM to proliferate and even survive

Question 8

proto-oncogenes

Answer 8

• encode proteins that promote the loss of growth control and act as accelerators of cell proliferation

Question 9

oncogenes

Answer 9

abnormally expressed or mutated forms of the proto-oncogenes that promote the loss of growth control

Question 10

cyclin D —- progression through the cell cycle

Answer 10

promotes

Question 11

SRC, FASK, RAS ACTIVATE THE MAPK CASCADE TO

Answer 11

promote adhesion dependent cell proliferation and survival
- links extracellular signals to the intracellular process that controls growth, proliferation, migration, and apoptosis.

Question 12

both copies of —– must be inactivates as well as a number of — activated in cells for cancer to arise

Answer 12

• tumour suppressor
• oncogenes