New Vaccine Destroys Melanoma and Ovarian Cancer Tumors

According to a new study, published in the leading scientific journal Proceedings of the National Academy of Sciences, is showing that a new vaccine/therapy is effective against Melanoma and Ovarian Cancer.

Dr. F. Stephen Hodi, from the Department of Medical Oncology and Cancer Vaccine Center, Dana-Farber Cancer Institute, and Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, led the study.

According to Hodi and colleagues, using fully human anti-CTLA-4 blocking monoclonal antibodies (the new vaccine) to patients with advanced stages of cancer significantly increases the immune response and induces the destruction of tumor in certain patients.

The study focuses on a receptor known as CTLA-4 (for cytotoxic T lymphocyte-associated antigen). CTLA-4 works like a valve, actually a "shut-off" valve for CD4+ T cells. These CD4+ T cells are involved in the immune response of the patient.

The new vaccine is specific for every cancer patient. Tumor cells (from the patient) are removed, and irradiated (to stop growing). After that these tumor cells are infused with a gene that produces a protein called GVAX. Finally, the modified tumor cells (you can call this the vaccine) are injected back into the patient.

What happens after the vaccination is that the GVAX gene causes the body to produce the GVAX protein. This protein is seen as a foreign threat and the immune response acts fully to destroy it.

The study mentioned encouraging results of this procedure. For example, researchers found that a single infusion of anti-CTLA-4 antibodies produced a great deal of tumor destruction in five metastatic melanoma and ovarian cancer patients. Also, tumors in eight of the participants either receded or became stable. Similar good results were obtained for ovarian cancer patients.