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Cancer and Cell Division. Cancer. What do you know about cancer? (list 5 things) What would you like to know about cancer ? (at least 3 things). http://www.youtube.com/watch?v=O3_PNiLWBjY. Checkpoints of Mitosis.
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Cancer • What do you know about cancer? (list 5 things) • What would you like to know about cancer? (at least 3 things)
Checkpoints of Mitosis • G1: before copying DNA, the cell checks itself to see if conditions are favorable for division • G2: the cell checks for mistakes in copied DNA; enzymes make necessary corrections • Mitosis checkpt: during metaphase, the cell checks that the chromosomes are attached to the spindle to ensure they divide properly
Genes and Cancer • Protonocogenes • Genes that encode proteins which regulate normal cell growth and division • Oncogenes • Protoncogenes that have mutated • Tumor suppressor genes • Genes that restrain growth (p53: halts cell division if it senses DNA is damaged) • Caretaker genes • Genes that control DNA integrity by repairing DNA
What causes Cancer? • Determining cause is complex. • damage genes or combine with existing genetic faults within cells to cause the disease • Chemicals: benzopyrene, PIP: heterocyclic amine • Radiation • Factors that increase the risk of cancer, • tobacco use, • certain infections, • radiation, • lack of physical activity, • poor diet and obesity, • environmental pollutants • Genetics: 5-10%
How are tumors classified? • Benign: mutations in ½ genes can lead to tumor • Localized population of cells • Proliferating cells result in cell death
Development of Cancer • Malignant: • Additional mutations lead to uncontrollable cell growth • Metastasis: • The uncontrolled growth has led to new capillaries providing a route for malignant cells to break away and travel throughout the body via blood or lymph
How do pathologist determine if cells are cancerous? • Cell size • Many nuclei • Large nuclei • Small amount of cytoplasm • Cytoplasm to nucleus ratio • Gene Screen:
Cancer: Uncontrolled cell growth What are possible Treatments? chemotherapy: anti-cancer drugs act to destory the tumor cell or stop cell division radiation therapy: ionizing radiation damages DNA to destroy the cell or slows the development of abnormal cells. Surgery: http://www.youtube.com/watch?v=RZhL7LDPk8w
Cancer Prevention • Diet • increase risk: obesity and alcohol consumption • a diet high in fruits and vegetables • Whole grain • Fish • low intake of red meat has being implicated but not confirmed. • consumption of coffee is associated with a reduced risk of liver cancer. • Stay away from animal fat and refined sugar.
Cancer Prevention • Screening • Self exams and diagnostic prevention • Genetic Testing • As part of diagnostic prevention • Medication • Inflammatory drugs • Aspirin (can reduce risk by 7%) • Estrogen drugs for breast and uterine cancer
Cancer Prevention • Vaccination • Help prevent some infection by some viruses • Human papillomavirus vaccine (Gardasil and Cervarix) cervical cancer • hepatitis B vaccine prevents infection with hepatitis B virus and decreases the risk of liver cancer
Skin Cancers • UV radiations causes mutation in the DNA of a skin cell • 75% of cancers are skin cancers • Most common cancers are caused by prolonged exposure to UV radiation from sunlight
Types of Skin Cancer • Three major types: 1. Basal Cell Carcinoma • Most common type of skin cancer • 2/3 of these cancers appear from chronic UV exposure
Skin cancer 2. Squamous cell carcinoma • Frequent in light, pale skin over 40 years old • Slow growing • Surgical removal or radiation
Squamous Cell Carcinoma Originates from epithelial cells
Skin Cancer 3. Malignant Melanoma • Arise from melanocytes • Usually in trunk of body and from a mole • Hard to treat
Malignant Melanoma Difficult to treat due to fast growing and invasion of deep tissues Risk increases with short, intermittent exposure to high-intensity sunlight.
Do you have Moles?Watch SUN Exposure! • A-asymmetry • B-Border • C-Color • D-diameter
Breast Cancer • cancer that forms in tissues of the breast, usually the ducts (tubes that carry milk to the nipple) and lobules (glands that make milk). • estimated new cases and deaths from breast cancer in the United States in 2010:New cases: 207,090 (female); 1,970 (male)Deaths: 39,840 (female); 390 (male) • http://www.cancer.gov/cancertopics/types/breast
Stats • For women in the U.S., breast cancer death rates are higher than those for any other cancer, besides lung cancer. • Besides skin cancer, breast cancer is the most commonly diagnosed cancer among U.S. women. More than 1 in 4 cancers in women (about 28%) are breast cancer. • Compared to African American women, white women are slightly more likely to develop breast cancer, but less likely to die of it. One possible reason is that African American women tend to have more aggressive tumors, although why this is the case is not known. Women of other ethnic backgrounds — Asian, Hispanic, and Native American — have a lower risk of developing and dying from breast cancer than white women and African American women.
about 5-10% of breast cancers can be linked to gene mutations (abnormal changes) inherited from one’s mother or father. Mutations of the BRCA1 and BRCA2 genes are the most common. Women with these mutations have up to an 80% risk of developing breast cancer during their lifetime, and they are more likely to be diagnosed at a younger age (before menopause). An increased ovarian cancer risk is also associated with these genetic mutations. In men, about 1 in 10 breast cancers are believed to be due to BRCA2 mutations and even fewer cases to BRCA1 mutations.
About 70-80% of breast cancers occur in women who have no family history of breast cancer. These occur due to genetic abnormalities that happen as a result of the aging process and life in general, rather than inherited mutations.
Types of Cancer • ductal carcinoma in situ (DCIS) • invasive ductal carcinoma (IDC) • invasive lobular carcinoma (ILC) • inflammatory breast cancer • male breast cancer • recurrent breast cancer • metastatic breast cancer
Prostate Cancer • testicular