Kapitel 20 Flashcards
Of tumors: self-limiting in growth - and noninvasive.
benign
Rare cancer cells capable of dividing indefinitely.
cancer stem cells
Genes whose alteration contributes to the causation or evolution of cancer by driving tumorigenesis.
cancer-critical genes
The generation of cancer.
carcinogenesis
Cancer of epithelial cells. The most common form of human cancer.
carcinoma
Disparate chemicals that are carcinogenic—due to the ability to cause mutations—when fed to experimental animals or painted repeatedly on their skin.
chemical carcinogens
Cancer arising from the epithelium lining the colon (the large intestine) and rectum (the terminal segment of the gut).
colorectal cancer
General term for a variety of different DNA viruses that can cause tumors.
DNA tumor virus
Mutations that are causal factors in the development of cancer.
drivers
Abnormally increased spontaneous mutation rate - such as occurs in cancer cells.
genetic instability
Human papillomavirus; infects the cervical epithelium and is important as a cause of carcinoma of the uterine cervix.
HPV
Cancer of white blood cells.
leukemia
Cancer of lymphocytes - in which the cancer cells are mainly found in lymphoid organs (rather than in the blood - as in leukemias).
lymphoma
Of tumors and tumor cells: invasive and/or able to undergo metastasis. A malignant tumor is a cancer. (Figure 20–3)
malignant
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.
metastases
The spread of cancer cells from their site of origin to other sites in the body. (Figures 20–1 and 20–16)
metastasis
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.
multidrug resistance
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)
oncogene
Class of viruses responsible for human warts and a prime example of DNA tumor viruses - being a cause of cancer of the uterine cervix.
papillomaviruses
Mutations that have occurred in the same cell as driver mutations - but which are irrelevant to the development of the cancer.
passengers
Tumor at the original site at which a cancer first arose. Secondary tumors develop elsewhere by metastasis.
primary tumor
Normal gene - usually concerned with the regulation of cell proliferation - that can be converted into a cancer-promoting oncogene by mutation.
proto-oncogene
A small family of proto-oncogenes that are frequently mutated in cancers - each of which produces a Ras monomeric GTPase.
Ras
The gene that is defective in both copies in individuals with retinoblastoma; its protein product plays a central role in cell-cycle control.
Rb gene
Phenomenon observed in primary cell cultures in which cell proliferation slows down and finally irreversibly halts.
replicative cell senescence
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.
retinoblastoma
Cancer of connective tissue.
sarcoma
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.
somatic mutations
A cell with an altered phenotype that behaves in many ways like a cancer cell (i.e. - unregulated proliferation - anchorage-independent growth in culture).
transformed
Process by which an initial mildly disordered cell behavior gradually evolves into a full-blown cancer. (Figures 20–8 and 20–9)
tumor progression
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)
tumor suppressor gene
Virus that can help make the cell it infects cancerous.
tumor virus
