ABOUT A DEADLY DISEASE

CANCER

Cancer is a class of diseases characterized by out-of-control cell
growth. There are over 100 different
types of cancer, and each is classified by the type of cell that is initially affected.Cancer harms the body whendamaged cells divide uncontrollably to form lumps or masses of tissue called tumors (except in the case of leukemia where cancer prohibits normal blood function by abnormal cell division in the blood stream)..

When a tumor successfully spreads
to other parts of the body and
grows, invading and destroying
other healthy tissues, it is said to
have metastasized. This process
itself is called metastasis, and the
result is a serious condition that is
very difficult to treat..

Cells can experience uncontrolled
growth if there are damages or
mutations to DNA, and therefore,
damage to the genes involved in cell
division. Four key types of gene are
responsible for the cell division
process: oncogenes tell cells when to
divide, tumor suppressor genes tell
cells when not to divide, suicide
genes control apoptosis and tell the
cell to kill itself if something goes
wrong, and DNA-repair genes
instruct a cell to repair damaged
DNA.
Cancer occurs when a cell's gene
mutations make the cell unable to
correct DNA damage and unable to
commit suicide. Similarly, cancer is a result of mutations that inhibit
oncogene and tumor suppressor
gene function, leading to
uncontrollable cell growth..

Carcinogens are a class of substances that are directly responsible for damaging DNA, promoting or aiding cancer.. Tobacco, asbestos, arsenic,
radiation such as gamma and x-rays,
the sun, and compounds in car
exhaust fumes are all examples of
carcinogens. When our bodies are
exposed to carcinogens, free radicals are formed that try to steal electrons from other molecules in the body. These free radicals damage cells and affect their ability to function normally..Cancer can be the result of a genetic predisposition that is inherited from family members. .As we age, there is an increase in the number of possible cancer-causing mutations in our DNA. Several viruses have also
been linked to cancer such as:
human papillomavirus (a cause of
cervical cancer), hepatitis B and C
(causes of liver cancer), and Epstein-
Barr virus (a cause of some
childhood cancers). Human
immunodeficiency virus (HIV) - and
anything else that suppresses or
weakens the immune system -
inhibits the body's ability to fight
infections and increases the chance
of developing cancer..

There are five broad groups that are
used to classify cancer.
1. Carcinomas are characterized by
cells that cover internal and external
parts of the body such as lung, breast, and colon cancer.
2. Sarcomas are characterized by cells that are located in bone, cartilage, fat, connective tissue, muscle, and other supportive tissues.
3. Lymphomas are cancers that begin in the lymph nodes and immune system tissues.
4. Leukemias are cancers that begin in the bone marrow and often
accumulate in the bloodstream.
5. Adenomas are cancers that arise in the thyroid, the pituitary gland, the adrenal gland, and other glandular tissues...

More on the treatment side in next blog..