Kapitel 20

Question 1

Of tumors: self-limiting in growth - and noninvasive.

Answer 1

benign

Question 2

Rare cancer cells capable of dividing indefinitely.

Answer 2

cancer stem cells

Question 3

Genes whose alteration contributes to the causation or evolution of cancer by driving tumorigenesis.

Answer 3

cancer-critical genes

Question 4

The generation of cancer.

Answer 4

carcinogenesis

Question 5

Cancer of epithelial cells. The most common form of human cancer.

Answer 5

carcinoma

Question 6

Disparate chemicals that are carcinogenic—due to the ability to cause mutations—when fed to experimental animals or painted repeatedly on their skin.

Answer 6

chemical carcinogens

Question 7

Cancer arising from the epithelium lining the colon (the large intestine) and rectum (the terminal segment of the gut).

Answer 7

colorectal cancer

Question 8

General term for a variety of different DNA viruses that can cause tumors.

Answer 8

DNA tumor virus

Question 9

Mutations that are causal factors in the development of cancer.

Answer 9

drivers

Question 10

Abnormally increased spontaneous mutation rate - such as occurs in cancer cells.

Answer 10

genetic instability

Question 11

Human papillomavirus; infects the cervical epithelium and is important as a cause of carcinoma of the uterine cervix.

Answer 11

HPV

Question 12

Cancer of white blood cells.

Answer 12

leukemia

Question 13

Cancer of lymphocytes - in which the cancer cells are mainly found in lymphoid organs (rather than in the blood - as in leukemias).

Answer 13

lymphoma

Question 14

Of tumors and tumor cells: invasive and/or able to undergo metastasis. A malignant tumor is a cancer. (Figure 20–3)

Answer 14

malignant

Question 15

Secondary tumors - at sites in the body additional to that of the primary tumor - resulting from cancer cells breaking loose - entering blood or lymphatic vessels - and colonizing separate environments.

Answer 15

metastases

Question 16

The spread of cancer cells from their site of origin to other sites in the body. (Figures 20–1 and 20–16)

Answer 16

metastasis

Question 17

An observed phenomenon in which cells exposed to one anticancer drug evolve a resistance not only to that drug - but also to other drugs to which they have never been exposed.

Answer 17

multidrug resistance

Question 18

An altered gene whose product can act in a dominant fashion to help make a cell cancerous. Typically - an oncogene is a mutant form of a normal gene (proto-oncogene) involved in the control of cell growth or division. (Figure 20–17)

Answer 18

oncogene

Question 19

Class of viruses responsible for human warts and a prime example of DNA tumor viruses - being a cause of cancer of the uterine cervix.

Answer 19

papillomaviruses

Question 20

Mutations that have occurred in the same cell as driver mutations - but which are irrelevant to the development of the cancer.

Answer 20

passengers

Question 21

Tumor at the original site at which a cancer first arose. Secondary tumors develop elsewhere by metastasis.

Answer 21

primary tumor

Question 22

Normal gene - usually concerned with the regulation of cell proliferation - that can be converted into a cancer-promoting oncogene by mutation.

Answer 22

proto-oncogene

Question 23

A small family of proto-oncogenes that are frequently mutated in cancers - each of which produces a Ras monomeric GTPase.

Answer 23

Ras

Question 24

The gene that is defective in both copies in individuals with retinoblastoma; its protein product plays a central role in cell-cycle control.

Answer 24

Rb gene

Question 25

Phenomenon observed in primary cell cultures in which cell proliferation slows down and finally irreversibly halts.

Answer 25

replicative cell senescence

Question 26

A rare type of human cancer arising from cells in the retina of the eye that are converted to a cancerous state by an unusually small number of mutations. Studies of retinoblastoma led to the discovery of the first tumor suppressor gene.

Answer 26

retinoblastoma

Question 27

Cancer of connective tissue.

Answer 27

sarcoma

Question 28

In cancer - one or more detectable abnormalities in the DNA sequence of tumor cells that distinguish them from the normal somatic cells surrounding the tumor.

Answer 28

somatic mutations

Question 29

A cell with an altered phenotype that behaves in many ways like a cancer cell (i.e. - unregulated proliferation - anchorage-independent growth in culture).

Answer 29

transformed

Question 30

Process by which an initial mildly disordered cell behavior gradually evolves into a full-blown cancer. (Figures 20–8 and 20–9)

Answer 30

tumor progression

Question 31

Gene that appears to help prevent formation of a cancer. Loss-of-function mutations in such genes favor the development of cancer. (Figure 20–17)

Answer 31

tumor suppressor gene

Question 32

Virus that can help make the cell it infects cancerous.

Answer 32

tumor virus