1. Lecture 28 Genetics of Cancer Copyright © 2010 Pearson Education Inc.

2. 1. Introduction

3. 2. Relationship of the Cell Cycle to Cancer

4. 3. Regulation of Cell Division in Normal Cells

5. 4. Cancers are Genetic Diseases 1. Lines of evidence indicating that cancers are genetic disorders: a. Some cancers are familial (hereditary), while others are sporadic (nonhereditary). b. Some viruses can induce cancer, indicating action of viral genes. c. Descendants of cancerous cells are all cancerous. d. Cancer risk rises with exposure to mutagenic agents. e. Specific chromosomal mutations are associated with certain kinds of cancer.

6. 5. Genes & Cancer 1. Four classes of genes are mutated frequently in cancer: a.Proto-oncogenes, whose products normally stimulate cell proliferation. b.Tumor suppressor genes, whose products normally inhibit proliferation. c. MicroRNA (miRNA) genes, which produce small RNAs that silence expression of other genes, including those involved in cell cycle control. d. Mutator genes, whose products ensure accurate replication and maintenance of the genome. 2. Oncogenes a. Tumor viruses i.RNA tumor viruses ii. DNA tumor viruses b. Retroviruses & Oncogenes

7. 6. Structure of retroviruses

8. 7. Life Cycle of Retroviruses

9. 8. Viral Oncogenes

10. 9.

11. 10. Membrane-Associated G Proteins Activated by Surface Receptors