Bio Chem - Cancer

Front 1

Oncogene

Back 1

Greek - cancer gene

A gene whose normal function is to stimulate cell growth that has become defective such that it is overactive, predisposing a cell to cancer.

Front 2

Proto-oncogene

Back 2

normal form of an oncogene
-growth stimulating gene before the defect

i.e. signal transduction genes

Front 3

Anti-oncogene

Back 3

tumor-suppressor

disposes cell to cancer when not active enough

i.e. cell cycle and DNA repair genes are anti-oncogenes.

Front 4

when does cancer occur?

Back 4

when a proto-oncogene has a gain of function and becomes an oncogene

or

when an anti-oncogene loses function

Front 5

how does Taxol make an effective anti-cancer drug?

Back 5

taxol stabilizes microtubules, preventing them from pulling apart during anaphase of mitosis. this prevents further proliferation of cells

Front 6

would a quiescent cell, such as a nueron, be affected by chemotherapuetic agents such as 2,6-diaminopurine or 6-mercaptopurine?

Back 6

quiescent cells are stuck in G0 and chemotherapuetic agents only target proliferating cells. Non-proliferating cells like nuerons would not be affected.

Front 7

Platelet-derived growth factor is a receptor involved in wound healing. Explain why it might be a proto-oncogene and how it might become an oncogene

Back 7

Platelet derived growth factor aids in wound healing which affects cellular growth. If PDGF is over expressed it can cause excess proliferation of cells which is cancer. Therefore, a normally functioning PDGF is a protooncogene since it has the ability to cause cell proliferation if overexpressed.

Front 8

list all cell cycle genes, all growth signal transduction genes and all DNA repair genes that may contribute to development of cancer when defective.

Back 8

Cell cycle genes: RB and p53
Growth signal transduction : ras, HER2
DNA repair: hMLH1, hMSH2

Front 9

are inherited defects responsible for the majority of cancers?

Back 9

while some cancers may be brought on by a single gene, many cancers involve several mutations of different genes. There can either be defects in the cell cycle, defects in growth signal transduction, defect in DNA repair, aberrant angiogenesis, or aberrant breakdown of the extracellular matrix.

Front 10

When gene A has a certain mutation it loses activity. Defects in this gene are also associated with cancer. Is the normal gene A a tumor supporessor, an oncogene, an anti-oncogene or a proto-oncogene

Back 10

Gene A would be a tumor suppressor and an anti-oncogene, since it loses activity when mutated. Possibly involved in control of cell cycle or DNA repair.

Front 11

Name some characteristics of matrix metalloproteinase proteins. What processes associated with cancer are matrix metalloproteinases involved in?

Back 11

Matrix metalloproteases proteins are proteins/enzymes that require a metal (ZnCa) to breakdown proteins in the extracellular matrix of a cell. These proteins allow cancer cells to metastasize.

Front 12

Why is cancer though of as a genetic disease even though it is often caused by outside agents such as pollutants or viruses/

Back 12

The outside agents cause mutations in the chromosomal DNA of cells, making cancer a genetic disease.

Front 13

Explain the mechanism by which melanoma cells may evade apoptosis

Back 13

melanoma cells contain the ability to inactivate the protein apaf-1, which is involved in signaling apoptosis.

Front 14

is cushing syndrome a cancer?

Back 14

no because it does not metastasize

Front 15

would agent 99 be a good cancer drug?

Back 15

No, by increasing blood circulation it may actually assist cancer cells