Exam 3 Ch 20

Question 1

What are the 2 defining heritable properties of cancer cells?

Answer 1

1. They reproduce in defiance of normal constraints
2. Invade and colonize places usually inhabited by other cells

Question 2

Benign tumor

Answer 2

Non-invasive BUT can become invasive

Question 3

Malignant tumor

Answer 3

Can invade tissue
Can form secondary tumors

Question 4

Metastase

Answer 4

Secondary tumors

Question 5

How are cancered classified?

Answer 5

By their site of origin

Question 6

Is the tumor microenvironment just cancerous cells?

Answer 6

No it consists of many cells

Question 7

Is a cancer cell caused by a single mutation?

Answer 7

No it is the accumulation of many mutations

Question 8

How do cells metastasize?

Answer 8

1. The must leave their tissue of origin (hard)
2. Enter into either the blood or lymphatic system
3. Travel to new site (easy)
4. Exit vascular system
5. Enter new tissue (hard)
6. Proliferate

Question 9

Carcinogenesis

Answer 9

The generation of cancer

Question 10

Mutagenesis

Answer 10

Cancer starting because of mutations

Question 11

6 key attributes of cancer cells

Answer 11

1. They grow when they should not
2. They divided when they should not
3. They escape from their home tissue
4. They survive and continue dividing even during conditions of stress
5. They are genetically and epigenetically unstable
6. The escape replicative senescence by producing telomerase or stabilizing their telomeres

Question 12

Cancer-critical genes

Answer 12

All genes whose alternation contributes to the causation or evolution of cancer (two types)

Question 13

Gain of function

Answer 13

Oncogenes
Overactive/overexpressed proto-oncogene that can promote cancer development
Only required on ONE allele

Question 14

Proto-oncogenes

Answer 14

gene that can undergo “gain of function” mutation

Question 15

Loss of function

Answer 15

Tumor suppressor genes
Loss of function mutation of these genes promotes cancer development
Requires BOTH alleles

Question 16

What are the three ways proto-oncogenes can be converted into oncogenes

Answer 16

1. Change in DNA sequence
2. Gene amplification
3. Chromosome rearrangement

Question 17

What are the 6 ways tumor suppressor genes can be inactivated?

Answer 17

1. Aneuploidy causes chromosome loss
2. mitotic recombination event
3. gene conversion during mitotic recombination
4. deletion
5. point mutation
6. epigenetic silencing

Question 18

How can cancers of the Uterine Cervix be prevented?

Answer 18

Vaccination Against Human Papillomavirus

Question 19

PARP inhibitors

Answer 19

Kill cancer cells that have defects in BRAC1 or BRAC 2 genes

Question 20

BRAC genes

Answer 20

Repair double stranded breaks

Question 21

Why are combination therapies useful in treating cancer?

Answer 21

It prevents rare mutant cells that are resistant to one drug from forming new tumors