1. Notes: Regulating the Cell Cycle

2. What is cancer?

4. If we want to cure cancer….
We must understand what the causes are. That means understanding the cell cycle.

5. Cells divide at different rates, depending on the cell type
Nerve and muscle cells usually stop dividing once developed
Skin cells divide frequently as skin is being replaced constantly

6. When control of the cell cycle fails, cells begin to divide uncontrollably, resulting in masses and failure of the cells to perform their normal functions. This condition is called cancer.
The study of cancer is called oncology.

7. What Controls Cell Division?
Cell cycle regulators
Cyclin (proteins)
Internal regulators
External regulators
Tumor Suppressor Genes (oncogenes)

8. Checkpoints
There are strict checkpoints in the cell cycle to ensure that each stage does not start before the last one has finished. Other checkpoints prevent cells dividing when their DNA is damaged - either allowing time to repair the damage or, if the DNA is too damaged, causing cell death (apoptosis).

9. Cancer = Uncontrolled cell growth
Uncontrolled means it takes over the cell cycle!
Causes can be environmental, genetic, or viruses

11. How is cancer treated?
Drugs (chemotherapy) are used to target cells that are dividing
Tumors can sometimes be removed via surgery
Radiation can target an area
Metastasis: When cancer cells move to a different part of the body.

12. Stem Cells
Stem cells are unspecialized cells that have the potential to differentiate (to become any type of cell)

13. Stem cells can be found in:
Human embryos
Some adult cells
Cord blood
The use of stem cells is controversial. Why?

14. Potential Uses for Stem Cells
Repair injuries of the brain and spinal cord
Cure some diseases (diabetes)
Replace organs (liver tissue, heart valves)