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* Mitosis
prophase, prometaphase, metaphase, anaphase and telophase and cytokinesis.
prophase: chromosomes condense
metaphase: chromosomes line up at the middle
* Cancer Cells
+ Lost control over growth and division
+ Don't self-destruct when worn out or damaged
+ Pile up and can break away and form new tumors in other parts of the body (metastasis)
+ Don't do their jobs
+ Crowd out the healthy cells and prevent them from doing their jobs
** Genes that cause cancer
+ Proto-oncogene - promotes cell division (gas pedal)
+ Oncogene (mutated proto-oncogenes) - promotes excessive cell divison (gas pedal stuck)
+ Tumor suppressor gene - normally inhibit cell division (brakes). when mutated, brakes don't work.
+ Usually more than one mutation (likely of each type) required to cause cancer
** P53
P53 (tumor suppressor gene) mutations identified in >50% of all human tumor cells
** Contributors to cancer risk
\approx \frac{1}{3} inheritance + environment
\approx \frac{2}{3} random mutations
** Cancer causing mutations can be inherited
*** Familial Cancers
+ Very rare, less than 15% of cancers
+ Gene mutations can be inherited from either or both parents
+ All of the cells in the body will have that mutation
+ Familiial cancer genes: APC (colon cancer), CRCA-1 and BRCA-2 (breast cancer + others), p16 (skin cancer)
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