1. Cell Cycle Regulation and Cancer
9.3

2. What regulates the cell cycle?
Cyclins (proteins)
Cyclin Dependent Kinases = CDK (enzymes)
Different combinations of cyclins and CDK’s control different activities of the cell.

4. Quality Control Checkpoints
G1- S : Check for damaged DNA before we make more
S: make sure the DNA has replicated properly
G2-M: check that the cell has everything it needs to divide.
M- Cytokinesis: Check for spindle fibers.

5. Can check points fail?
Yes
What do the failures lead to?
Cancer

6. What is cancer? The uncontrolled growth and division of cells.
How does cancer kill?
The overgrowth of cells crowds out normal cells and damages tissue function.
Who can cancer occur in?
Anyone

7. How does a cell become cancerous?
Cell cycle is not regulated and the cell continues to divide as long as it has the nutrients it needs.
Cancer cells spend a shorter time in interphase than normal cells.
Mutations occur in DNA that control the production of proteins that regulate the cell cycle.

9. Genetic component to cancer
Multiple changes to DNA (mutations)
Happens over a life time
Risk of certain cancers increase with age.
Individuals can inherit these changes in DNA from their parents increasing their risk for cancer.

10. Environmental factors can also effect risk of cancer.
Carcinogens are substances known to cause or contribute to cancer.

11. Apoptosis Programmed cell death
Naturally occurs in the webbing between hands and feet in fetuses.
Occurs in the petiole of leaves causing them to fall from trees.
Cells with damaged DNA usually go through apoptosis

13. Cancer Treatments

14. Stem Cells After fertilization the mass of cells divides repeatedly.
Embryonic Stem Cell
Adult Stem Cells
After fertilization the mass of cells divides repeatedly.
cells that are not specialized
Can be separated and become specialized.
Controversial
Unspecialized cells found in various tissues.
Can develop into specialized cells.
Used a lot in research.
Less controversial

16. Words to know Benign Malignant Metastasis Mutation Carcinogen
Apoptosis
Stem cells
Cyclin Dependent kinases (CDKs)
Cyclins

17. Henrietta Lacks Born in 1920 in Roanoke, VA
Died of cervical cancer in 1951
A cell from her tumor was used to start of cell line. Called HeLa.
Instrumental in developing Polio Vaccine
Still used in cell research today.
Henrietta Lacks