Cell Division Gone Wrong Cancer

 Cancer is a disease of uncontrolled cell division. It starts with a single cell that loses its control mechanisms due to a genetic mutation. That cell starts dividing without limit, and eventually kills the host.  Some types of cancers run in families while others are triggered by environmental factors.

A Tumour  Uncontrolled growth and division may create a rapidly growing mass of cells that form a lump or tumour.  Cells that stay together and have no serious effects on surrounding areas are called benign.  A mass of cells that interfere with the function of neighbouring cells and tissues is malignant. These cells are considered cancerous.

Causes  Every time a cell divides, its DNA is faithfully duplicated. Usually this process is error-free and the genetic information in the daughter cells is exactly the same as the parent cell. Sometimes though, random changes occur. These random changes are called mutations.

 Some mutations are caused by carcinogens: environmental factors that cause cancer.  Tobacco smoke (9 out of 10 cases of lung cancer)  Radiation (x-rays, UV from tanning beds)  Some viruses (HPV)  Some plastics  A lot of organic compounds

 Some cancers appear to be hereditary: DNA passed from one generation to the next.  Breast cancer  Colon cancer

Screening for Cancer  Checking for cancer, even though there are not symptoms, is screening for cancer.  At home, self check  Routine medical check up (especially if there is a history or breast or colon cancers)  Women – pap tests, breast checks  Men – testicular check, PSA check for prostate  Both - colonoscopy

Cancer Treatment  Two basic treatments: surgery to remove the tumor, and radiation or chemicals to kill actively dividing cells.  It is hard to remove all the tumor cells. Tumors often lack sharp boundaries for easy removal, and metastatic tumors can be very small and anywhere in the body.

Radiation and Chemotherapy  Radiation and chemotherapy are aimed at killing actively dividing cells, but killing all dividing cells is lethal: you must make new blood cells, skin cells, etc. So treatment must be carefully balanced to avoid killing the patient.

Chemotherapy  Chemotherapy also has the problem of natural selection within the tumor.  If any of the tumor cells are resistant to the chemical, they will survive and multiply.  The cancer seems to have disappeared, but it comes back a few years later in a form that is resistant to chemotherapy.  Using multiple drugs can decrease the risk of relapse: it’s hard for a cell to develop resistance to several drugs at the same time.

Biophotonics  The newest weapon in the fight against cancer uses beams of light to detect and treat cancer.  It is very sensitive and can help in early detection.  There are fewer side effects and can more accurately target cancerous tissue.

Reducing your Cancer Risk  Cancer prevention and early detection are very important.  Inform your self about you medical history, family history, and carcinogens in the environment to help you make healthier lifestyle choices.