Methotrexate is a part of the group of drugs referred to as anti-metabolites which are chemotherapy drugs generally used as a treatment for various types of cancer.  Methotrexate is often used in conjunction with other drugs to slow or stop the growth of cancer cells. Medical professionals have also administered this drug as a treatment for pleural mesothelioma, which is a cancer caused by prolonged exposure and inhalation of asbestos fibers.

How It Works

Methotrexate, like many other drugs used in chemotherapy, has been shown to be an effective inhibitor of cancerous cell division. The process involves complex compounds in the drug that prevent cells from efficiently using folate, which is necessary for the formation of both DNA and RNA in cells that are ready to divide. Cells make duplicate sets of chromosomes as they mature; when cellular division occurs both of the daughter cells will have an exact replica of the parent DNA. Cancer cells grow and divide more rapidly than normal, healthy cells, thus affecting them to a greater degree when folate cannot be used to make DNA and RNA copies.

Other cells can also be affected, especially those which are present to fight off infections. These include the red and white cells in the bloodstream as well as any antibiotics present as a result of medications being taken. Hair cells are also vulnerable, and most patients experience hair loss during chemotherapy. Methotrexate is administered either as an intravenous injection or in tablet form, and the dosage varies from one individual to another depending on the condition being treated. Side effects include a decrease in the blood cells being created in the bone marrow, nausea, or diarrhea.

Treating Mesothelioma

Due to the positive results concerning methotrexate in patients with certain types of lung cancer, health professionals have begun administering the drug as a chemotherapy regimen for mesothelioma. This disease is caused when asbestos fibers that are present in the lungs begin to act as a carcinogen, affecting nearby cells and causing cancerous growths.

Asbestos fibers are a form of silicate compound, are extremely tiny, and are easily inhaled by employees in various industrial fields. Asbestos insulation can break down over time, allowing free-floating fibers to be inhaled and become embedded in a person’s lung tissue or pleural lining. Methotrexate is not a cure for mesothelioma, but is effective in slowing the growth and division of these cells. Mesothelioma tends to exhibit a long latency period, meaning patients are usually diagnosed in the later stages. Cancer cells reproduce quite rapidly, which is the reason chemotherapy drugs such as methotrexate are used to target them. This drug was approved for use by the U.S. Food and Drug Administration as of 1984.