Immunotherapy: Enlisting The Immune System To Fight Cancer

Researchers are beginning to look in a new direction for cancer treatment: the body's own immune system. A trial wasconducted on women with progressive, recurrent, or advanced cervical cancer in which a live Listeria cancer vaccine, Lovaxin C, was used for the treatment. The women in the study had all failed chemotherapy, radiotherapy or surgery, but this vaccine has the potential to be effective in shrinking tumors and preventing new ones from forming.

Listeria monocytogenes is a bacterium commonly found in soil, stream water, sewage, plants, and food. In the body, Listeria thrives within antigen presenting cells, which consume foreign invaders, and thus directs an immune response. Listeria is being bioengineered to cause it to secrete a tumor-specific antigen fused to a listerial protein, thus focusing a strong immune attack. Researchers are combining their knowledge about what enables Listeria to infect human immune systems and how humans are able to get rid of Listeria in order to combine and target these immune responses against cancer.

The study was performed on 15 patients, with the following results: five patients had progression of their cancer, seven were stable, and one patient showed a partial response to the therapy, who is now tumor-free. Three women had approximately 20% tumor reductions. Other studies were conducted on patients with prostate and other types of cancer.


http://www.sciencedaily.com/releases/2008/04/080415111730.htm