Cancer develops from the dysregulation of normal cell growth in any tissue.The cancerous cells become unresponsive to growth regulation from the body, allowing them to divide out of control and develop into a tumor. There are several strategies that can be used to treat cancer, such as chemotherapy. The drawback to several cancer treatments is that they target normal cells as well as cancer cells, leading to a number of unpleasant side effects. The development of antibody therapies to treat certain cancers allows doctors to target the cancer cells, resulting in fewer side effects for patients.
Rituxan
Rituxan is a therapeutic antibody, which can be used treat several forms of cancer. According to the Rituxan website, it is used to treat leukemia and lymphoma, cancers that affect the blood and immune system, respectively. Rituxan works by targeting a protein called IL-2, which promotes the development of certain cancers. IL-2 is an inflammatory protein, so it's presence within a tissue leads to an immune response. Inflammation helps drive the development of cancer, since inflammation aids in the building of new blood vessels at the site of inflammation, a requirement for tumor growth. Sustained inflammation around a tumor increases the blood supply into the tumor, and then drives tumor progression. Rituxan prevents inflammation, and therefore slows cancer growth.
Erbitux
Erbitux is another antibody treatment commonly used to treat colon cancer, and head and neck cancers. Erbitux works by targeting a protein called EGFR, which is found on the surface of cells. EGFR senses growth factors present in a tissue, and signals for cell division as a response. In cancer, EGFR dysfunctions so it always tells the cell to divide, driving tumor growth. Many colon cancers, or head and neck cancers contain high levels of the EGFR protein, so these types of cancers are effectively treated by Erbitux. Antibody therapy is generally used after other treatments have failed, or to treat very aggressive tumors, according to the Erbitux website.
Herceptin
Herceptin is an antibody therapy used to treat breast cancer. Herceptin targets a protein called HER2, which is closely related to EGFR. In normal cells, HER2 is found on the surface of the cell, and interacts with other proteins on the cell surface to promote cell division. In many cases of breast cancer, HER2 is mutated, or found at such high levels that it always sends a signal for cell division, promoting breast cancer development. Herceptin works by preventing the activation of the HER2 protein to stop cell division signaling. Herceptin also trains the immune system to destroy cells containing mutant HER2, killing off the cancer cells. Herceptin is only used to treat HER2-containing breast cancer tumors.
