Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Genes and Disease: Cancer Chapter 23 Tumors (Neoplasms) • Masses that show abnormal growth • Benign tumors – Grow slowly – Remain in place – Moles are example • Malignant tumors (cancer) Cancer Characteristics • Cells lack normal contact inhibition • Weakened capacity for adhesion – Metastasis • Some kinds produce HCG • Some produce angiogenin, which encourages blood vessel growth Metastasis Cells break away Enter blood vessel Emerge in new tissue Proto-Oncogenes • Normal genes that regulate cell growth and development • Encode growth factors, proteins that regulate cell adhesion, and protein signals for cell division • If altered, may be converted to an oncogene Oncogenes & TumorSuppressor Genes • Oncogene does not act alone to cause cancer • Cancer usually requires mutations in several genes, including at least one tumor-suppressor gene • p53 is a tumor-suppressor gene that is mutated or absent in about half of cancers Other Routes to Cancer • • • • Heredity Viruses Radiation Breakdown in immunity • Environmental chemicals – Pesticides – Industrial chemicals – Hydrocarbons in smoke – Plant and fungal carcinogens Warning Signs of Cancer • • • • • • • Change in bowel or bladder habits A sore that does not heal Unusual bleeding Thickening or lump Indigestion, difficulty swallowing Obvious change in wart or mole Nagging cough or hoarseness Diagnosing Cancer • Blood tests for tumor markers • Medical imaging • Biopsy • DNA probe Treating Cancer • Chemotherapy • Monoclonal antibodies • Immunotherapy Interferons Cancer vaccines Interleukins Limiting Cancer Risk • • • • • • • Avoid tobacco Limit alcohol Maintain desirable weight Eat healthy diet Be aware of potential chemical exposure Protect skin from sunlight If menopausal, consider risks of estrogen Types of Cancer & Their Origins • Sarcoma (connective tissue) • Carcinoma (epithelium) • Adenocarcinoma (glandular tissue) • Lymphoma (lymphoid tissue) • Leukemia (blood-forming regions of bone marrow) Breast Cancer 1 in 9 women Risk factors Obesity Late childbearing Early puberty Late menopause Family history Detection Self examination Mammogram Treatment Surgery Drugs Tamoxifen Reproductive System Cancers Uterine cancer (endometrium, cervix) Pap smear Ovarian cancer Taxol Testicular cancer Self examination Prostate cancer Digital rectal exam PSA blood test Oral and Lung Cancers Oral cancers • Tobacco use • Alcohol use Lung cancers kill more people than any other cancers Lung cancers • Tobacco use • Secondhand smoke • Asbestos, industrial chemicals Digestive System Cancers • Stomach cancer • Pancreatic cancer • Liver cancer • Colon cancer Cancers of the Blood and Lymphatic System Lymphomas • Non-Hodgkin lymphoma • Hodgkin’s disease • Burkitt lymphoma Leukemias • Stem cells overproduce white blood cells • Vincristine and vinblastine Skin Cancer • Most common of all cancers • Basal cell carcinoma • Squamous cell carcinoma • Malignant melanoma – Deadliest skin cancer – Kills 5,600 per year in United States