1. When good cells go bad

2. The Cell Cycle and Cancer

3. ?What is cancer
Caner is defined as the continuous
. uncontrolled growth of cells
.A tumor is a an abnormal proliferation of cells
Benign tumors stays confined to its original
location
Malignant tumors are capable of invading
surrounding tissue or invading the entire body
Tumors are classified as to their cell type
Tumors can arise from any cell type in the
body
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4. This video shows what the
cancer is

5. Animation: How Cells Reproduce
((cancer

6. Normal and Cancer cells
1. Click on picture for cell cycle animation –
will go to www.cancerquest.org)
2. Use alt-tab keys to go between website
and power point presentation.
3. Click on blank space to proceed to next slide.)

7. Cancer continued; three cancer types
Carcinomas; constitute 90% of cancers, are 
cancers of epithelial cells
Sarcomas; are rare and consist of tumors of 
connective tissues (connective tissue, muscle,
.(bone etc
Leukemias and lymphomas; constitute 8% of 
tumors. Sometimes referred to as liquid tumors.
Leukemias arise from blood forming cells and
lymphomas arise from cells of the immune system
(.(T and B cells

8. Some Major Types of Cancer
In general, a cancer is named according to the type of 
tissue in which it first forms
 Sarcomas: cancer of connective tissue
 Carcinomas: cancer arising from epithelium
 Lymphomas: cancer of lymphoid tissue
 Leukemias: cancer of stem cells
 Gliomas: cancer of brain cells

9. Cancer is a disease of the cell cycle. Some of the
. body’s cells divide uncontrollably and tumors form
Tumor in Colon
Tumors in Liver

10. While normal cells will stop dividing if there is a mutation in the
.DNA, cancer cells will continue to divide with mutation

11. Due to DNA mutations, cancer cells ignore the
.chemical signals that start and stop the cell cycle
2 animations of cancer cells dividing: click on picture

12. Normal cells show
contact inhibition
Cancer cells lack
contact inhibition

13. They keep growing
And growing
And growing
And growing

14. Cancer Spreads Step-by-Step

15. This Cancer Cell Is Surrounded by
White Blood Cells

16. 4
Cell
division
3
DNA
repair
G2
1
Mitosis
G1
Cell grows,
doubles in
size
S
2
Chromosome
duplication
G1/S checkpoint

18. Outside cell
Signal molecule
Signal–receptor
binding
Receptor
Plasma
membrane
Cytoplasm
Protein
molecules
Cellular response
Nucleus
Changes in gene
expression
Stepped Art
p. 183

19. • Benign: localized and of
small size
• Cells that closely resemble,
and may function, like
normal cells
• May be delineated by a
fibrous (Basal lamina)
capsule
• Become problems due to
sheer bulk or due to
secretions (e.g. hormones)

20. Normal Moles Are Common
Examples of Benign Growths

21. Cancer : Malignant
Malignant tumors: high rate of division, properties may vary compared
to cells of origin. Most malignant cells become metastatic
Invade surrounding tissue and establishment of secondary areas of
growth: Metastasis

22. Main Features of Benign and
Malignant Tumors

23. Smoking
Number one factor in cancer, either direct 
((smoker) or indirect (secondhand smoke
Related to cancers of oral cavity, larynx, esophagus,and lungs
Accounts for 30% of all cancer deaths 
Most have very low survival rate (e.g. 13% lung cancer
sufferers survive beyond 5 yrs


24. Lungs of Non-Smoker and Smoker

25. Other Factors Also May Lead to
Cancer
Chemical carcinogens 
Carcinogens: cancer-causing substances that can 
lead to a mutation in DNA
Asbestos, vinyl chloride, and benzene
Hydrocarbons in cigarette smoke
Aflatoxin: fungal product
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Radiation 
UV from the sun and tanning lamps 
X-rays: medical and dental 
Radon, cosmic rays, and gamma radiation 

26. X-rays

27. (Skin Cancer (1
million new cases in U.S. per year 1~ 
Almost all cases related to UV light exposure from 
sun or tanning lamps
Increasing, may be due to outdoor recreation or 
moving to regions with more sun exposure
Lightly pigmented people higher risk, genetic 
characteristics can affect the susceptibility

28. Melanoma

29. Other Factors Also May Lead to
Cancer
Chemical carcinogens 
Carcinogens: cancer-causing substances that can 
lead to a mutation in DNA
Asbestos, vinyl chloride, and benzene
Hydrocarbons in cigarette smoke
Aflatoxin: fungal product
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

Radiation 
UV from the sun and tanning lamps 
X-rays: medical and dental 
Radon, cosmic rays, and gamma radiation 

30. Some Industrial Chemicals Linked
to Cancer

31. Biopsy Is the Only Sure Way to
Diagnose Cancer
Biopsy 
Removal and microscopic examination of tissue 
Seven common cancer signs: CAUTION 

32. Cancer Treatment and Prevention
When a person is diagnosed with cancer, a variety of 
weapons are available to combat it
 Chemotherapy drugs
 Radiation therapy
 Surgery

33. Chemotherapy and Radiation Kill
Cancer Cells
Radiation therapy 
Used when cancer is small or has not 
spread
Radioisotopes used, e.g., Ra-226 and 
Co-60
Chemotherapy and radiation destroy 
healthy cells
More precise treatments 
Monoclonal antibody treatment 
Interferon treatment; limited at 
present

34. Good Lifestyle Choices Can
Limit Cancer Risk
Avoid tobacco completely 
Maintain a desirable weight; eat a low-fat diet with 
plenty of fruits and vegetables
.
Make sure your living and work environment is safe 
from carcinogens
Protect your skin from the sun’s UV rays 

35. SUMMARY
Normal Cell Division
Cancer Cells
DNA is replicated
1. Mutations occur in the
1.
.properly
DNA when it is
.replicated
Chemical signals start. 2
.and stop the cell cycle
Chemical signals that. 2
start and stop the cell
Cells communicate with. 3
.cycle are ignored
each other so they
don’t become
Cells do not. 3
.overcrowded
communicate with each
.other and tumors form