Cancer

Checkpoint proteins such as p53 are not necessary for

normal cell growth and division.

E cadherin

________- keeps cells of tissue adhering to each other.

DNA alterations can lead to effects on

gene expression that ultimately affect cell division, and thereby lead to cancer.

Integrins

________- keeps cells adhering to their substrate.

Replicative senescence

________: finite number of cell divisions most likely due to loss of telomerase activity.

Sarcomas

________: arise from connective tissue or muscle cell.

Missense mutations

________: chemical mutagens have been shown to cause ________ leading to cancer.

Cancer

________: the continuous uncontrolled growth of cells.

cell division

An oncogene may promote cancer by keeping the ________ signaling pathway in a permanent "on "position.

Carcinomas

________: cancers arising from epithelial cells.

viral genome

Some viruses cause cancer because they carry an oncogene in the ________.

Leukemias

________: hematopoietic cells and nervous system.

Malignant

________: cells have acquired ability to invade surrounding tissue.

Tumors can arise from

any cell type in the body.

Growth factors bind to

cell surface and initiate cascade, activating specific genes, leading to cell division.

If a proto-oncogene becomes overexpressed,

it will promote cancer.

Retroviral insertions

________: viral DNA inserts into a chromosome, putting a viral promoter next to a proto- oncogene.

Gene amplifications

________: increase in copy number results in too much protein.

somatic cells

Most carcinogens, such as UV light and certain chemicals in cigarette smoke, are mutagens that promote genetic changes in ________.

Proteins called cyclins and cyclin- dependent protein kinases (cdks) are responsible for

advancing a cell through the four phases of the cell cycle.

Checkpoint proteins

________ check the integrity of the genome and prevent a cell from progressing past a certain point in the cell cycle.

If the damage is minor, p53

halts the cell cycle until the damage is repaired.

Tumor

any abnormal proliferation of cells

Benign tumors

stay confined to its original location

Malignant tumors

capable of invading surrounding tissue or invading the entire body

Neoplasm

tumor

Benign

cells of neoplasm are clustered together

Leukemias

hematopoietic cells and nervous system

Replicative senescence

finite number of cell divisions most likely due to loss of telomerase activity

Carcinogens

agents that increase the likelihood of developing cancer

Mutations in genes for cell growth signaling proteins can change them into oncogenes

producing abnormally high level of activity

Chromosomal translocations

two chromosomes break and switch ends

Oncogene

mutant form of a normal gene

E-cadherin

keeps cells of tissue adhering to each other

p53

about 50% of all human cancers are associated with defects in this gene

ex

Rb (retinoblastoma)