Understanding Cancer: Common Misconceptions and Cell Cycle Regulation

2. Upon completion of this lesson you will be able to: • Identify common misconceptions about cancer • Create a graphic organizer to represent what you know about cancer • Summarize the characteristics of the cell cycle and its regulation • Recognize the consequences of uncontrolled cell division • Compare the appearance, structure, function, and replication of healthy cells to those of cancerous cells • Describe how cancer develops

3. Steve and Nikki are fraternal twins in high school. They recently learned that their mother has been diagnosed with cancer. They have no idea what this really means for their mom and for them.

4. Mom has a doctor’s appointment so she can’t make my game. Dad said he would leave work early to make the game. I’m glad he’s coming but I wish mom could make it and I wonder if we should just stay home. I still don’t know what cancer really is and Nikki and I don’t want to bug mom and dad. Can someone just tell me what exactly is cancer?

6. Question 1: The risk of dying from cancer in the United States is increasing. FALSE. The risk of dying from cancer in the United States has decreased from 1975 to 2012.

7. US Mortality Files, National Center for Health Statistics, Centers for Disease Control and Prevention. Rates are per 100,000 and are age-adjusted to the 2000 US Std Population (19 age groups - Census P25-1130). Source: National Cancer Institute. SEER Statistics Review 1975-2006.

8. Question 2: Cancer can be spread from person to person. FALSE. Cancer cannot be passed from one person to another. Though cancer itself isn’t contagious, sometimes viruses, which are contagious, can lead to the development of cancer.

9. Question 3: What someone does as a young adult has little effect on their chance of getting cancer later in life. FALSE. Most cases of cancer are the consequence of many years of exposure to several risk factors.

10. Question 4: There is currently a cure for cancer but the medical industry won’t tell the public about it because they make too much money treating cancer patients. FALSE. Plenty of doctors and their loved ones die of cancer each year. Why would anyone hide such an important discovery? Think about the speed with which other medical breakthroughs in vaccines and antibiotics have been announced and applied.

11. Question 5: Treating cancer with surgery can cause it to spread throughout the body. FALSE. Specialists in cancer surgery know how to safely take biopsy samples and to remove tumors without causing the cancer to spread. In many cases, surgery is an essential part of the cancer treatment plan.

12. Question 6: Cancer can be effectively treated. TRUE. The five major types of treatment for cancer are surgery, radiation, chemotherapy, biologic therapies, and therapies that boost the patient’s immune system.

13. Effective cancer treatments can include several types of Cancer Warriors. What do each of the following professionals do to fight cancer?

14. Question 7: Cancer is a group of over 100 diseases. TRUE. • The main categories of cancer include: • Carcinoma • Sarcoma • Leukemia • Lymphoma and myeloma • Central nervous system cancers

15. Question 8: Cancer cells can be distinguished from normal cells because of their abnormal growth. TRUE. Normally, cells grow and divide to produce more cells as they are needed to keep the body healthy. Sometimes, this orderly process goes wrong. New cells form when the body does not need them, and old cells do not die when they should.

16. Question 9: Cancer can only occur in specific cells in the body. FALSE. The body is made up of many types of cells, and all cancer begins in cells. Cancer can develop in any cell in the body, which is why there are so many different types.

17. Question 10: Cancer develops because of abnormal gene function. TRUE. Scientists have learned that cancer is caused by changes in genes that normally control the growth and death of cells. Certain lifestyle and environmental factors can change some normal genes into genes that allow the growth of cancer.

18. Construct a concept map illustrating what you know about cancer. You can use circles, ovals, squares, or other shapes for main concepts or ideas. Cancer

19. Based on what you learned today, write a response to Steve’s question: What is cancer?

21. Nikki has a lot of questions and Steve is not sure how to help answer them. What would you want to know if you were in their shoes?

22. I remember learning about the phases of the cell cycle, but don’t understand the deal with cancer. I wonder what mom went through before now! I really want to help but I just keep wondering about what’s going to happen. Also, will I get cancer, too?

23. How do healthy and cancerous cells differ? Healthy Cancerous

24. Healthy Cancerous Cytoplasm Nucleus Chromatin Nucleolus

25. Healthy Cancerous Cytoplasm Nucleus Chromatin Nucleolus Large Cytoplasm Single Nucleus Single Nucleolus Fine Chromatin Small Cytoplasm Multiple Nuclei Multiple & Large Nucleoli Coarse Chromatin

26. Less Characteristics of Normal & Cancerous Cells Less Less Less Even More More More Irregular

27. Nucleus _________________________________________ Mitochondria _________________________________________ Ribosomes _________________________________________ Golgi Apparatus _________________________________________ Centrioles _________________________________________ Chromosomes _________________________________________ Endoplasmic Reticulum _________________________________________ Structure Function

28. NucleusControl center of the cell. Contains all genetic information. MitochondriaPowerhouse of the cell. Converts sugar to usable energy by cellular respiration. RibosomesSite of protein synthesis. Golgi ApparatusPackaging center of the cell. Packages and secretes proteins. CentriolesOrganizes microtubules (spindle fibers) for mitosis. ChromosomesMade of condensed DNA and proteins. Codes for genetic traits. Endoplasmic ReticulumTransports intracellular materials.

29. Phases of Cell Cycle Gap 0 (G0): Resting Stage Gap 1 (G1): Growth Synthesis (S): DNA Replication Gap 2 (G2): Growth Mitosis (M): Nuclear Division and Cytokinesis

30. Source: The presidents and Fellows of Harvard College., 2013

31. The cell has several systems for interrupting the cell cycle if something goes wrong. Checkpoints in G1 and G2 look for DNA damage and try to repair it. Damage that is so severe that it cannot be repaired will lead a cell to self-destruct by apoptosis. Mitosis checkpoint detects failure of spindle fibers to attach to kinetochores and will arrest cell in metaphase until corrected.

32. All checkpoints require the function of a complex of proteins. Mutations in the genes encoding some of these proteins have been associated with cancer. Checkpoint failures due to gene mutations allow the cell to continue dividing despite damage to its integrity.

34. Source: The presidents and Fellows of Harvard College., 2013

35. Cell Cycle Quality Control Source- Don Bliss for the National Cancer Institute 

36. When a tumor suppressor gene is mutated, there is loss of function resulting in cell cycle checkpoint failure and uncontrolled division of abnormal cells.

37. Tumor suppressor genes are like the brakes of a car. When the brakes lose function, the car moves out of control. Similarly, when tumor suppressor genes lose function, the cells grow out of control.

38. Tumor suppressor genes are like the brakes of a car. When the brakes lose function, the car moves out of control. Similarly, when tumor suppressor genes lose function, the cells grow out of control.

39. When a proto-oncogene is mutated (now called oncogene), there is gain of function resulting in a cell cycle checkpoint failure and uncontrolled division of abnormal cells.

40. Proto-oncogenes are like the gas pedal of a car. If the gas pedal gets stuck in the “on” position, a car keeps moving whether the pedal is pushed or not. Similarly, when a proto-oncogene mutates into an oncogene, a cell will keep dividing even when there are no messages to divide

41. Gene function is activated Proto-oncogenes are like the gas pedal of a car. If the gas pedal gets stuck in the “on” position, a car keeps moving whether the pedal is pushed or not. Similarly, when a proto-oncogene mutates into an oncogene, a cell will keep dividing even when there are no messages to divide.

42. Normal Cell Division The cell proceeds with normal cell division. At least one error is detected at one or more cell cycle checkpoints. Once the errors are repaired and checkpoints are cleared, the cell divides normally. Tumor Suppressor Gene MutationTumor suppressor gene loses function. cells will continue to divide. Proto-oncogene MutationProto-oncogene mutates into an oncogene. The cells will continue to divide.

43. What is the difference between the three cell division scenario? Let’s find out. Divide into three groups and assign parts for a role play. 1 2 3

44. Create a model that explains the relationship between the cell cycle and the development of cancer. Your model can be an illustration, a description, a video explanation, or a physical representation.

45. I remember learning about the phases of the cell cycle, but don’t understand the deal with cancer. I wonder what mom went through before now! I really want to help but I just keep wondering about what’s going to happen. Also, will I get cancer, too?