Characteristics of Cancer Cells - How do they differ from “normal” cells

Plasma Membrane Abnormalities Increase in transport & permeablility They allow things in and out of the cell that they normally should not Surface proteins are lost / altered / or new proteins appear

Changes in the Cytosol Cytoskeleton shrinks and / or becomes disorganized There is a shift in enzyme activity Example Reliance on glycolysis although oxygen is present

Abnormal Growth & Division Benign a.Loss of inhibitors to prevent overcrowding in tissues b.Cell population increases at high densities…… tumor c.Proteins form that trigger an increase in blood capillaries that service the growing mass

Abnormal Growth & Division Malignant a.Diminished capacity for adhesion to substrates - Cells aren’t anchored in parent tissue and metasticize….. spread

Stages of Cancer Stage 1 – Initiation Early genetic changes Proto oncogenes – Genes necessary for normal cell function are altered by structure or expression then become…… Oncogenes – Any gene having the potential to produce cancer

Genetic changes are causes by – INITIATORS: a substance that starts damage to cells that can lead to cancer (carcinogen) examples – cigarette smoking radiation barbecue meats

Stages of Cancer Stage 2: Promotion Promoters cause change in “normal” cells already damages by initiators to change to cancer cells Examples: environmental pollutants Alcohol This stage can take years

Stages of Cancer Stages 3 – Progression Growth of the cancer cells Metastasis – when the cell leaves its proper space and invades other tissues