Cancer

What does the word cancer mean to you?

What is Cancer? Cancer - disease where cells grow out of control and invade, erode and destroy normal tissue Cancer cells lack differentiation (not specialized) Normal cells enter the cell cycle only about 50 times; cancer cells can enter the cell cycle repeatedly. Normal cells undergo Apoptosis which is a programmed cell death to prevent overgrowth of cells.

Cancer Development Abnormal cell growth called neoplasm Abnormal growth results from the mutation of genes that regulate the cell cycle Carcinogenesis, the development of cancer is gradual—it may take decades before a cell has the characteristics of a cancer cell.

Origin of Cancer Mutations in genes for repair enzymes of DNA can cause cancer. If proteins that start cell cycle or inhibit cell cycle are changed (mutated) it can cause cancer. Normal DNA segments have ends that shorten with each replication, eventually signaling the cell to end division; cancer cells have enzymes that keep their DNA segments at a constant length and thus the cells to continue dividing.

Characteristics of Cancer Cells Have abnormal nuclei Lack differentiation Chromosomes mutated; may be duplicated or deleted. Gene amplification, extra copies of genes Do not undergo apoptosis

Characteristics cont. Do not have contact inhibition Normal cells are anchored and stop dividing when in contact with other cells; Growth not inhibited and will invade and destroy normal tissue Cancer cells pile on top of each other to form a tumor. Cancer cells undergo metastasis and angiogenesis Metastasis – cancer spreads throughout body; new tumors away from primary tumor. Angiogenesis - formation of new blood vessels to bring nutrients and oxygen to tumor.

Types of Tumors Benign: slow growth, non-invasive, no metastasis (not cancerous) Malignant: rapid growth, invasive, potential for metastasis (cancerous)

Types of Cancers

Deadliest 10 Lung and bronchial – 792,495 Colon and rectal - 268,783 Breast Cancer - 206,983 Pancreatic Cancer – 162,878 Prostate Cancer – 144,926 Leukemia – 108,740 Non-Hodgkin Lymphoma – 104,407 Liver and intrahepatic bile duct cancer – 79,773 Ovarian Cancer – 73,638 Esophageal Cancer – 66,659

Prognosis Depends on whether the tumor has invaded surrounding tissue, whether there is lymph node involvement, and whether there are metastatic tumors elsewhere in the body. Depends on what type of cancer and how early was detected. For example some forms of skin cancer are basal cell carcinoma, squamous cell carcinoma, and melanoma. Basal cell carcinoma rarely ever causes death, while 77% of skin cancer deaths are caused by melanoma.

Is cancer a heritable disease? There are heritable cancer syndromes but a majority are not. Cancer is a genetic disease, but the majority of mutations that lead to cancer are somatic (body cell)

What causes the mutations that lead to cancer? Viruses: HPV --> cervical cancer Bacteria: H. pylori --> gastric cancer Chemicals --> B[a]P --> lung cancer UV and ionizing radiation --> skin cancer What do these agents have in common? They are all Mutagens

Treatments Surgery Chemotherapy Radiation Therapy Targeted Therapy Immunotherapy Hyperhermia Bone Marrow and Peripheral Blood Stem Cell Transplant Laser Therapy Molecular Targeted Therapy http://www.cancer.org/Treatment/TreatmentsandSideEffects/TreatmentTypes/index

7 ways to Reduce Risk Don’t use tobacoco Eat healthy diet – fruits, veggies, limit alcohol Maintain healthy weight; physical activity Protect yourself from the sun Get immunized – Hepatitis B and HPV Avoid Risky behaviors – safe sex and no shared needles Take early detection seriously Self exams Regular doctor visits