Cancer

Question 1

Cancer changes can be ____, or arise during a persons lifetime from ___ and __ sources

Answer 1

Inherited

Exogenous and endogenous

Question 2

Genetic changes that contribute to chancer tend to affect 3 main types of genes

Answer 2

1. DNA repair genes
2. Tumor suppressor genes
3. Proto-oncogenes

Question 3

What are DNA repair genes? What happens if there is a mutation to one of these genes?

Answer 3

Codes for proteins involved in fixing damaged DNA, such as an exonuclease or endonuclease.

A mutation in these genes tend to develop additional mutations in other genes.

Question 4

What are tumor suppressor genes? What happens if there is a mutation in one of these genes?

Answer 4

They code for proteins that inhibit the cell cycle. Negative regulators of the cell cycle. If DNA damage is detected the protein will halt the cell cycle and recruit enzymes to repair the DNA. If it cannot be repaired, the protein can trigger apoptosis.

Ex: p53

If the tumor suppressor gene is mutated, the cell cycle proceeds unregulated.

Question 5

What are proto-oncogenes What happens if there is a mutation in one of these genes?

Answer 5

Code for proteins that stimulate the cell cycle.
Positive regulators of the cell cycle. When these cells are mutated, they can become overactive cancer causing genes (now called oncogenes).

Results in cells dividing uncontrollably.

Question 6

Oncogene

Answer 6

A gene which in certain circumstances can transform a cell into a tumor cell.

Cancer causing mutation in a proto-oncogene gene. Proto-oncogenes are positive regulators of the cell cycle. If mutated, the gene can become an oncogene and results in cells dividing uncontrollably.

Question 7

Benign

Answer 7

Tumor that does not invade surrounding tissue.

Question 8

Malignant

Answer 8

Cancer. If the malignancy spreads from its site of origin to another part of the body.

Question 9

Different types of cancer treatments

Answer 9

1. Surgery
2. Radiation using X ray
3. Chemotherapy using drugs (pill, IV)
4. Immunotherapy (strengthening immune system)
5. Hormone therapy (drugs are used to inhibit hormones that are active in certain cancers such as breast and prostate)
6. Bone marrow transplant (Stem cell transplant that allows for a higher dosage of chemo )
7. Gene therapy (introduce genetic material into cells to compensate for abnormal genes or make a beneficial protein)

Question 10

Why does bone marrow transplant as a cancer treatment allow for a higher dosage of chemo?

Answer 10

Because chemotherapy kills stem cells. However, if you are able to replenish the stem cells, you could have a more intense chemo-therapy without risking too much loss of the stem cells.