Cancer+Questions+SLS

November 12, 2008 Science-Human Bio**
 * Shelby Smith

Define: apoptosis, telomeres, metastisis, tumor, proto-oncogenes, oncogenes, growth factor, tumor suppressor gene, oncology, carcinoma, sarcoma, leukemia, lymphoma

Cancer cells do not look like a differentiated epithelial, muscle, nervous, or connective tissue; instead, it looks distinctly abnormal.
 * 1. What do cancer cells look like?**

The nucleus of the cancer cells are enlarged and may contain an abnormal amount of chromosomes.
 * 2. What is unusual about the nuclei of cancer cells?**

Cancer cells don’t die because they keep dividing for an unlimited number of times. They are immortal.
 * 3. Why don't cancer cells die?**

The stages of cancer can be divided into three stages: Initiation: A single cell undergoes a mutation that causes it to begin to divide repeatedly. Promotion: A tumor develops, and the tumor cells continue to divide. As they divide, they undergo mutation. Progression: One cell undergoes a mutation that gives it a selective advantage over the other cells. The cell then has the ability to invade the surrounding tissues.
 * 4. Describe the three phases of the development of cancer**.

Mutations in proto-oncogenes and mutations in tumor-suppressor genes cause uncontrollable growth.
 * 5. Mutations in what two types of genes lead to uncontrollable growth?**

P53 is a protein that turns on genes that stop the cell cycle and activates repair enzymes. If the repair is impossible, the p53 protein promotes apoptosis, programmed cell death. When p53 is not available, cancer tumors can develop.
 * 6. What is p53? How does it cause cancer?**

RB (Retinoblastoma protein) turns on the gene for cyclin D and other genes whose products promote the entry into the S phase of the cycle cell. RB protein is always functional, and the result is, again, too much active cyclin in the cell.
 * 7. What is RB? How does it cause cancer?**

The most common cancer cases for females and males are breast, prostate, lung and bronchus and colon and rectum cancer.
 * 8. What are the most common cancers cases for males and females?**

Lung and bronchus, colon and rectum, breast, prostate.
 * 9. What are the most common cancer deaths for males and females?**