Cancer Unit PDF

Cancer Unit Part 1: Cellular Function and Cancer 1. What is cancer? ○ Cancer is the uncontrolled growth and division of abnormal cells in the body that can invade nearby tissues and spread to other parts of the body. 2. What are the chances of developing cancer in your lifet...

Cancer Unit Part 1: Cellular Function and Cancer 1. What is cancer? ○ Cancer is the uncontrolled growth and division of abnormal cells in the body that can invade nearby tissues and spread to other parts of the body. 2. What are the chances of developing cancer in your lifetime? ○ The lifetime risk of developing cancer varies by factors such as age, lifestyle, and genetics, but roughly 1 in 2 men and 1 in 3 women in the U.S. will develop cancer at some point in their lives. 3. How do changes in cell function result in cancer? ○ Mutations in genes that regulate cell growth, division, and death (such as tumor suppressor genes and proto-oncogenes) can lead to uncontrolled cell proliferation, resulting in cancer. 4. How does cancer influence the physiology of the body? ○ Cancer disrupts normal tissue function, may form tumors, and can spread (metastasize) to other parts of the body, affecting organs and leading to failure of physiological systems. 5. The activities of a cell are ultimately under the control of what in the cell? ○ The activities of a cell are controlled by its DNA, located in the nucleus, which contains the genetic instructions for the cell's functions. 6. What are the major components of a cell and their functions? ○ Major components include: Nucleus: Stores genetic information. Mitochondria: Produces energy. Endoplasmic Reticulum (ER): Synthesizes proteins and lipids. Ribosomes: Protein synthesis. Plasma Membrane: Regulates entry and exit of substances. Cytoplasm: Contains cell organelles. 7. What is specialization in cells? ○ Specialization (differentiation) refers to cells developing specific structures and functions, allowing them to perform unique tasks in the body (e.g., muscle cells vs. nerve cells). 8. What are the roles of enzymes in cellular functions? ○ Enzymes act as biological catalysts, speeding up chemical reactions within cells, such as metabolism, DNA replication, and protein synthesis. 9. How is information stored within the chemical structure of a DNA molecule? ○ Information is stored in the sequence of nucleotide bases (adenine, thymine, cytosine, and guanine) in DNA, which encodes the instructions for making proteins. 10. What are the stages of gene expression from DNA to functional protein? ○ Transcription: DNA is transcribed into mRNA. ○ Translation: mRNA is translated into a protein at the ribosome. 11. How does the cell cycle function to prevent a cell from becoming cancerous? ○ The cell cycle includes checkpoints (G1, G2, M phase) that monitor DNA integrity and control cell division. If errors are detected, repair mechanisms are activated or the cell undergoes apoptosis (cell death).  12. What are the series of events in the cell cycle? ○ The main phases are: G1 Phase: Cell growth. S Phase: DNA replication. G2 Phase: Preparation for mitosis. M Phase: Mitosis (cell division). 13. What is the location of the major checkpoints? ○ Checkpoints are located: G1/S Checkpoint: Ensures DNA is undamaged before replication. G2/M Checkpoint: Ensures DNA has been properly replicated. M Checkpoint: Ensures chromosomes are aligned correctly before division. 14. What is the structure and function of a chromosome? ○ A chromosome is a tightly packed structure of DNA and proteins. It ensures DNA is accurately replicated and distributed during cell division. 15. What are the stages of mitosis? ○ The stages include: Prophase: Chromosomes condense. Metaphase: Chromosomes align in the middle. Anaphase: Sister chromatids separate. Telophase: Nuclear membranes reform. Cytokinesis: Cytoplasm divides. 16. How do mutations in genes such as BRCA1 and p53 contribute to cancer? ○ Mutations in tumor suppressor genes like BRCA1 (breast cancer) and p53 (guardian of the genome) reduce the cell's ability to repair DNA damage, leading to cancer. 17. How do mutations change the information content of a DNA molecule? ○ Mutations alter the sequence of nucleotide bases, which can result in incorrect or dysfunctional proteins being produced. 18. How do mutations in tumor suppressor genes lead to cancer? ○ Tumor suppressor genes prevent uncontrolled cell growth. Mutations disable this function, allowing cells to proliferate unchecked. 19. How do mutations in proto-oncogenes lead to cancer? ○ Proto-oncogenes regulate normal cell division. When mutated, they become oncogenes, which drive excessive cell proliferation. 20. How do growth factors change the rate at which a cell divides? ○ Growth factors bind to cell receptors and stimulate signaling pathways that promote cell division and growth. Cancer Unit Part 2: How Does Cancer Affect My Body and Its Treatment? 1. What is the difference between a normal cell and one that has the potential to be cancerous? ○ Normal cells grow, divide, and die in an orderly fashion, whereas pre-cancerous cells exhibit unregulated growth and evasion of normal cell death mechanisms. 2. What are the general characteristics of cancer cells? ○ Cancer cells have uncontrolled growth, evasion of apoptosis, the ability to invade tissues, and often genetic instability. 3. Why does cancer cause a loss in cellular specialization? ○ Cancer cells often revert to a more primitive, less specialized state, which allows them to proliferate uncontrollably and spread. 4. Why do cancer cells increase the rate of angiogenesis? ○ Cancer cells promote the growth of new blood vessels (angiogenesis) to supply the growing tumor with nutrients and oxygen. 5. How does loss of specialization lead to metastasis of cancer cells? ○ Loss of specialization allows cancer cells to become more mobile and invade other tissues, leading to metastasis. 6. What are the criteria associated with staging cancer? ○ Cancer staging is based on the size of the tumor, its spread to lymph nodes, and whether it has metastasized to other organs (TNM system). 7. What are the characteristics of stage 1 cancer? Stage 2? Stage 3? Stage 4? ○ Stage 1: Small, localized tumors. ○ Stage 2: Larger tumors or spread to nearby tissues. ○ Stage 3: Cancer has spread to nearby lymph nodes. ○ Stage 4: Cancer has metastasized to distant organs. 8. How does cancer affect normal physiology and result in death? ○ Cancer disrupts organ function, depletes the body’s resources, and may cause organ failure, leading to death. 9. Why is homeostasis important in a living organism? ○ Homeostasis maintains the stable internal conditions necessary for survival. Disruptions in homeostasis can lead to disease or death. 10. How does cancer disrupt organ function? ○ Cancerous tumors can physically obstruct or replace normal tissues, hindering organ function. 11. How can cancer negatively influence body chemistry? ○ Cancer can alter metabolism, release harmful substances (toxins), and cause imbalances in electrolytes, hormones, and proteins. 12. What are the common methods by which the presence of cancer is detected in the body? ○ Methods include imaging (MRI, CT scans), biopsy, blood tests, and genetic testing. 13. How can genetic tests indicate cancer susceptibility? ○ Genetic tests identify mutations in genes (like BRCA1 or BRCA2) that increase the risk of certain cancers. 14. How do the results of a normal blood test compare with those of an individual with cancer? ○ Cancer may lead to abnormal levels of blood cells, markers (e.g., tumor antigens), or other substances that indicate the presence of a tumor. 15. How are MRI, CT, and ultrasound tests different? ○ MRI: Uses magnetic fields to create detailed images of soft tissues. ○ CT Scan: Uses X-rays to create detailed cross-sectional images.  ○ Ultrasound: Uses sound waves to image tissues, commonly used for non-invasive scans. 16. What is chemotherapy? ○ Chemotherapy is the use of drugs to kill or inhibit the growth of cancer cells. 17. How do alkylating agents work? ○ Alkylating agents damage DNA and prevent cancer cells from replicating. 18. How do alkaloids work? ○ Alkaloids interfere with microtubules during cell division, preventing mitosis. 19. How do topoisomerase inhibitors work? ○ These drugs inhibit topoisomerase enzymes, which are essential for DNA replication and cell division. 20. What are the different forms of radiation that may be used to treat cancer? ○ External radiation: High-energy rays directed at the tumor from outside the body. ○ Internal radiation (brachytherapy): Radioactive substances placed inside or near the tumor. 21. How do we use external radiation to treat cancer? ○ External beams target the cancerous area with precision to minimize damage to surrounding tissues. 22. How do we use internal radiation to treat cancer? ○ Radioactive materials are placed close to or inside the tumor, delivering radiation directly to cancer cells. 23. How can other biotechnology be used to treat cancer in the future? ○ Techniques like CRISPR gene editing, immunotherapy, and targeted drug delivery are promising advancements. 24. What types of immune cells may be used to treat cancer? ○ T-cells (CAR-T therapy), natural killer cells, and dendritic cells are being used or developed in immunotherapy. 25. What is gene editing? ○ Gene editing involves modifying or correcting genes within cells, often to repair mutations or enhance the immune system. 26. How can vaccines be used to treat or prevent cancer? ○ Cancer vaccines stimulate the immune system to recognize and destroy cancer cells or protect against cancer-causing viruses (e.g., HPV vaccine).