Honors Biology 2016 What is Cancer?

I. What is Cancer? A. Normally, cells are forced to undergo programmed cell death when: DNA is damaged Replication has not occurred properly A checkpoint in growth has been reached. B. Cancer is the uncontrolled growth of cells.

M phase includes both Mitosis and Cytokin esis! I. What is Cancer?

Oncogenes→Gene→Protein→ GO! II. Genetic Causes of Cancer A. Genes controlling the cell cycle: 1. Oncogenes a. DNA sequences that code for proteins that give the cell a “green light” signal to GO and proceed through the cell cycle.

Tumor Suppressor Gene → Protein→ GO! II. Genetic Causes of Cancer A. Genes controlling the cell cycle: 2. Tumor Suppressor Genes a. DNA sequences that give the cell the red light signal to STOP and wait.

1. How do you make a car GO? → Step on the GAS or the ACCELERATOR 2. How do you make a car STOP? → Step on the BRAKES Question: Using this information, What 2 ways could a car get out of control? II. Genetic Causes of Cancer: B. An Analogy: Driving a Car

II. Genetic Causes of Cancer C. How does a cell become cancerous? Mutation in proto-oncogene → active oncogene → Cell divides more frequently than it would otherwise. 1. Proto-oncogenes vs. Oncogenes Proto- oncogenes = controlled Oncogenes = uncontrolled

II. Genetic Causes of Cancer C. How does a cell become cancerous? 2. Loss of Tumor Suppressor Genes Mutations in TS genes can cause cells to lose the ability to stop passing its checkpoints.

Proto-oncogenes and Tumor Suppressor Genes Video II. Genetic Causes of Cancer C. How does a cell become cancerous?

1. Proto-oncogenes become oncogenes so they are making the “go” proteins without any controls. 2. Tumor suppressor genes are mutated so they no longer give the instructions for making the “stop” proteins II. Genetic Causes of Cancer D. Summary

QUICK CHECK! With a partner, answer the following questions: 1. What type of macromolecule contains genes? 2. What are changes in this macromolecule called? 3. What can cause DNA mutations? ● DNA damage from environmental agents: UV radiation (sunlight), nuclear radiation, certain chemicals, etc. ● Mistakes made during DNA replication ● Viruses???

Viruses can add and change the DNA sequence of a cell that it infects.

Metastasis: the spread of cancer cells to other parts of a body III. How does Cancer Spread?

A. Types of Tumors 1. Malignant tumors affect an organ’s ability to do its job. 2. Benign tumors do NOT affect an organ’s ability to do its job. III. How Does Cancer Spread?

III. How does Cancer Spread? B. Tumor Development

IV. Cancer Treatment A. Surgery 1. Remove the cancer cells from the patient 2. Oldest form of cancer treatment B. Radiation Therapy 1. Damage and kill cancer cells by hitting them with high energy radiation

C. Chemotherapy 1. Kill cancer cells by injecting chemicals that target rapidly dividing cells 2. Common side effects: Nausea, hair loss, fatigue, and vomiting IV. Cancer Treatment

D. Immunotherapy 1. Inject antibodies specifically made to identify and “tag” cancer cells 2. Activates a patient’s own immune system to attack the cancer cells. IV. Cancer Treatment

E. Gene therapy ● Change the abnormal genes to make them normal ● Although there is much hope for gene therapy, it is still experimental. IV. Cancer Treatment

● What 2 types of genes help control how fast a cell moves through the cell cycle? V. How does cancer “run in the family”?