1. How Cancer Works

2. Cancer is the 2nd leading cause of death in the U.S.
This year over ½ a million Americans will die of cancer
#1 cause of death in the U.S. is ____________

3. What is Cancer?
Cancer is out-of-control cell division of mutated (abnormal) cells
Normally, cells divide in a timely and orderly fashion.
Also, if a cell is damaged it will not divide and will actually self-destruct

6. What is a Tumor? Is it Cancer?
Tumor = a mass of tissue that forms when cells divide at an accelerated rate

7. Pics of Tumors
Osteosarcoma (cancerous bone tumor)

8. Pictures of Tumors
Brain Tumor

9. Tumors can cause destruction in 3 major ways
Put pressure on nearby tissues/organs
Invade tissues and organs directly and damage or destroy them
Make invaded tissue more susceptible to infection

11. Not all Tumors are Cancerous
Benign Tumors = tumors that are NOT cancerous
Will not spread to other parts of the body
Usually will not grow back once it is removed
However, can still be very dangerous and harmful

12. Cancerous Tumors Malignant Tumors = these ARE cancer
Can spread to other tissues/organs
More likely to come back after it is removed

13. Benign vs. Malignant Tumors

14. How Cancer Spreads Metastasis = the spreading of cancerous cells
Millions of cancer cells are released from the site of the tumor into the blood stream

15. Breast Cancer

16. Metastasis

17. Metastasis

18. Stages of Cancer

19. Understanding the Cause of Cancer
Cancer occurs when the cell cycle becomes unregulated
Cell Cycle = a timely cycle of growth and replication of a cell

20. Understanding the Cause of Cancer
Checkpoint Proteins act to ensure that:
Stages of the cycle happen at the proper time
There are no mistakes
If a checkpoint protein detects that something is wrong, the cell will not divide!

21. Cell Cycle Checkpoints

22. Cell Cycle Checkpoints

23. Understanding the Cause of Cancer
Cancer results from a breakdown in these checkpoint proteins
They are not doing their job and therefore the cell divides when it should not

25. Understanding the Cause of Cancer
Why do the checkpoint proteins break down?
DNA is the “instruction book” for making these proteins
If there is damage to the DNA, then checkpoint proteins may not be made or will be made incorrectly

26. Understanding the Cause of Cancer
If the DNA makes nonfunctional checkpoint proteins:
There will be too much cell division
Division will occur even though there are major errors/damage

27. Genetic/Natural Causes of Cancer
What causes DNA mutations? (Changes in the DNA message)
You can inherit faulty genes from your parents
Genes may mutate (accidentally) in your cells over time
Mistakes can be made when DNA copies itself in preparation for cell division

28. Understanding the Cause of Cancer
What causes DNA mutations? (Changes in the DNA message)
Carcinogens = a cancer-causing substances or exposures

29. Examples of Known Carcinogens
Tobacco smoking
Smokeless tobacco (chew)
UV Radiation
X-rays and gamma rays
Asbestos
Wood Dust
Alcoholic Beverage Consumption

30. Examples of Known Carcinogens
HPV (Human Papilloma Virus)
Hepatitis B
Hepatitis C
Soot
Silica (that is small enough to be inhaled)
Coal Tar
Estrogen Steroids
Chemicals used in furniture and cabinet making

31. Carcinogens in Cigarettes
There are 81 known carcinogens in cigarettes!!

32. Healthy Lung
Lung Cancer

33. Cancer Treatments
Surgery – remove the tumor

34. Cancer Treatments Radiation Therapy
X-rays are directed precisely at the tumor site
X-rays kill the cells by damaging the DNA

35. Cancer Treatments
Chemotherapy – uses chemicals to kill fast-growing cells in the body
Can shrink/eliminate a tumor
Can kill cancer cells that have metastasized
Can kill cells in any part of the body