Cancer and Inflammation
Inflammation is a defense response to harmful stimuli (such as pathogens, damaged
cells, or irritants) in living tissue with a vascular system, and is a protective response
involving immune cells, blood vessels, and molecular mediators. The function of
inflammation is to eliminate the initial cause of cell injury, clear out necrotic cells and
tissues damaged, and initiate tissue repair. Inflammation has five classical signs,
which are heat, pain, redness, swelling, and loss of function. Inflammation is a
generic response, and therefore it is regarded as a mechanism of innate immunity, as
compared to adaptive immunity, which is specific for each pathogen. Too little
inflammation could lead to progressive tissue destruction by the harmful stimulus
(e.g. bacteria) and compromise the survival of the organism.
In contrast, chronic inflammation may result in a host of diseases, such as hay fever,
periodontitis, atherosclerosis, rheumatoid arthritis, and even cancer (e.g., gallbladder
carcinoma). Inflammation is normally closely regulated by the body. Inflammation
can be classified as either acute or chronic. Acute inflammation is the initial response
of the body to harmful stimuli and is achieved by the increased movement of plasma
and leukocytes (especially granulocytes) from the blood into the injured tissues. A
series of biochemical events and the inflammatory response propagates and matures,
involving the local vascular system, the immune system, and numerous cells within
the injured tissue. Prolonged inflammation, known as chronic inflammation, leads to
a progressive shift in the type of cells present at the site of inflammation, such as
mononuclear cells, and is characterized by simultaneous destruction and healing of
the tissue from the inflammatory process.
