Experimental Melanoma Vaccine

Melanoma is a comparatively rare but deadly form of skin cancer. Although melanoma accounts for less than 5% of skin cancer cases, it causes nearly 80% of skin cancer deaths. The American Cancer Society estimates that more than 68,700 cases will be diagnosed and that more than 8,600 people will die from the disease in 2009. In the US, the percentage of people who develop melanoma has more than doubled in the past 30 years, but the rate has remained steady since 2000.

Melanoma is a disease of “insufficient host immunity,” which means the body’s immune system does not recognize the cancer as foreign. In other words, the immune system has trouble distinguishing normal cells from diseased melanoma cells. Thus, the host’s immune system, the body’s natural defender against disease, is not called into action to fight the cancer.

For the past 4 years, my laboratory research at the Los Angeles Biomedical Research Institute at Harbor-UCLA Medical Center has focused on problems of host immunity and therapies designed to trigger or train the host immune system to recognize and fight melanoma cells. Our team has developed an experimental vaccine that is made of a specific intracellular bacterium with recombinant DNA that induces a powerful host immune response and incites a strong immune attack specifically against cancer cells.
 
This potential of a melanoma vaccine is of particular importance because melanoma, while primarily a cancer of the skin, can metastasize, or spread to other organs, such as the liver, lungs, or brain. When that happens, the disease becomes very difficult to control, and a complete cure is more challenging. In our preclinical laboratory research on mice, we have demonstrated that the immune response is capable of partial protection against metastatic melanoma. We are now focused on developing bacterial strains that target melanoma antigens for eventual applications in humans with brain tumors or metastatic melanoma.

While a cure for this deadly disease is still in the future, research like ours on immune therapy and other research efforts such as molecular targeting and gene therapy are yielding promising results. Such studies will lead to a better understanding of the mechanisms involved in boosting immune system functioning and enhance the design of future melanoma therapies.