Cancer Cancer Cancer is a disease of uncontrolled

Cancer

Cancer • Cancer is a disease of uncontrolled cell growth. • It starts with a single cell that loses its control mechanisms due to a mutation. • That cell starts dividing without limit, and eventually kills the host. • The spreading of cancer from one location to another is called metastasis.

Cancer • Cancer is the second leading cause of death in the United States. • There are many types of cancer, but all cancers start with a single abnormal cell. Abnormal cells multiply quickly. They spread to other parts of the body, invading healthy body tissue and organs. • Almost half of all cancer deaths can be prevented with early detection and treatment.

Cancer • There are more than 100 types of cancer, including breast cancer, skin cancer, lung cancer, colon cancer, prostate cancer, and lymphoma. • Cancer symptoms vary widely based on the type of cancer. • Cancer treatment includes chemotherapy, radiation, and surgery.

Normal cells vs. Cancer Cells • Normal cells are controlled by several factors. – Normal cells stay in the G 1 stage of the cell cycle until they are given a specific signal to enter the S phase, in which the DNA replicates and the cell prepares for division. Cancer cells enter the S phase without waiting for a signal. – Normal cells are mortal. This means that they can divide about 50 times and then they lose the ability to divide, and eventually die. This “clock” gets re-set during the formation of the gametes. Cancer cells escape this process of mortality: they are immortal and can divide endlessly – Normal cells that suffer significant chromosome damage destroy themselves due to the action of a gene called p 53. Cancer cells either lose or ignore its message and fail to kill themselves.