1. Cancer progresses through accumulation of multiple mutations
Each successive mutation allows those cells to proliferate more quickly than those around it.

2. Cancer is a genetic disease, but not usually inherited.
Most cells in the body are somatic cells.
Most mutations are in the somatic cells.
Germline mutations are inherited by offspring

3. …but it sometimes is inherited and runs in families.
Each cell has 2 copies of each tumor suppressor gene.
Both copies must be mutated for cancer to form.
If first mutation is inherited, all cells are susceptible to 2nd mutation.

4. 2-hits in retinoblastoma
Cancer of the retina
Small tissue with only one tumor suppressor gene active.
Most people get only 1 mutation in any given cell
No cancer
Some people get 2 mutations in any given cell
Cancer in one eye
Some people inherit mutation in all of their cells. Next mutation causes cancer.
Cancer in both eyes usually by age 5.

5. What causes mutations to occur and spread?
Mutations may be inherited
Carcinogens – any agent involved in the promotion of cancer
Smoke (esp. cigarette smoke)
Radiation / sun
Chemicals / solvents
Infectious diseases (eg Human papillomavirus)
Food (esp. charred meat)
Hormones (eg. Estrogen)
Many, many others!

6. External signals that control cell proliferation: growth factors

7. External signals that control cell proliferation

8. Cell proliferation: tumors recruit blood vessels to supply oxygen and nutrients.
Tumors secrete Growth factors that promote angiogenesis (formation of blood vessels

9. Tumor growth
2nd mutation increases growth rate and changes appearance of cells
First mutation causes rapid growth
After recruiting blood supply, may metastasize to other tissues

11. Risk Factors Family history Tobacco use Smokeless tobacco Diet
But only 5% of cancers are inherited
Tobacco use
30% of all cancers and 87% of lung cancer
Smokeless tobacco
Oral and pancreatic cancers
Diet
Eat fruits and vegetables
Avoid charred meats
Avoid preserved meats

12. Risk factors Being sedentary Alcohol Irregular medical care
Moving helps push food through your intestines, limiting exposure to carcinogens
Alcohol
Irregular medical care
Cancer goes undetected
Sunlight (UV and other radiation)
Chemical carcinogen exposure
Infectious agents (eg. HPV for cervical cancer)

13. Treatment options Surgery Removal of cancerous tissue Radiation
Kills cancer cells (usually targeted to specific tissue)
Chemotherapy
Uses chemicals to kill cancer cells (throughout body)
Biological immunotherapy
Strengthens immune system
Transplants
Particularly Bone Marrow for leukemias