Vaccine for Skin Cancer
Reported January 21, 2005
(Ivanhoe Newswire) — The most deadly form of skin cancer — advanced melanoma — may be successfully treated by injecting patients with tumor proteins, according to two articles published in the latest Journal of Experimental Medicine.
Belgian researcher Pierre Coulie and colleagues studied what effect vaccinating patients with tumor antigens (called MAGE-3) might have on patients immune cells, which are known as killer T-cells. Researchers found injecting patients with these tumor antigens increased the amount of killer T-cells that can attack a tumor.
However, results also show that these killer T-cells mainly recognized tumor proteins not contained in the vaccine. In one patient, while T-cells specific to the antigen did become detectable, they did not expand to as large of a number as the non-tumor specific T-cells after the vaccination.
Many melanoma patients have detectable, tumor-specific T-cells in their blood and tumors, but these T-cells are not able to attack the tumor, and it is unclear why. Also unclear is why vaccination can cause tumors to regress, when tumor specific T-cells do not increase nearly as much as non-tumor specific T-cells.
Dr. Coulie believes the few tumor specific T-cells that are stimulated by the vaccine may create an environment that somehow wakes up the other T-cells to attack the tumor.
SOURCE: Journal of Experimental Medicine, 2005;201:249-257
