1. Cancer Overview

2. Cancer: unrestrained cell growth
Abnormal cell division process
Mitosis: Cell division resulting in two identical daughter cells

3. Mitosis ©http://www.accessexcellence.org/RC/VL/GG/images/MITOSIS.gif

4. When is it Appropriate for Cells to Mitose?
1. Repair
Same cell replacement to repair damaged tissue
Example: you scratch cells from your esophagus

6. 2. Growth
One cell becomes 2, 2 cells become 4, 4 cells become 8
Example: babies growing into adults, in utero even faster—1 fertilized egg becomes hundreds of trillions in 9 months

8. 3. Replacement
Same cell replacement AND same number of them
Cells have a life span
Example: red blood cells, skin cells, inside gut lining

9. Red Blood Cells

10. Metaplasia
Replacement of a specialized cell with a less specialized cell (ex. fibroblast)

12. Fibroblast migrate into cut area and fill it in
Scab is pushed off by upward movement of fibroblast—actually raises above the skin
Can happen on heart, liver, skin, etc

13. A growth of cells due to a specific physiological need
5. Hyperplasia
A growth of cells due to a specific physiological need
If you do not need it, it does not happen 

14. Hyperplasia Examples
A. Angiogenesis: the growth of capillaries (often to by-pass occlusion)
Increases capillary network to tissue

15. Angiogenesis ©http://www. clevelandclinic

16. B. Bacterial Infection: bump up the number of white blood cells
5,000-10,000 wbc per 1 ml of blood
You contract strep throat, 17,000-30,000 wbc in the same amount of blood

17. Endometrial Proliferation:
Endometrial is the lining of the uterus

18. Proto-oncogenes
Mitosis in any given cell is controlled by proto-oncogenes
Oncogenes: a gene with a DNA sequence that can cause cancer (a proto-oncogene gone wrong)
Think a gas pedal in a car that is stuck on the floor

20. Oncology: study of tumors
Oncologist: physician specialized in the diagnosis and treatment of tumors