Investigators at the University of Pennsylvania say an experimental breast cancer vaccine designed to spur a patient's dendritic cells to attack cancer cells has proved promising in a small human study.
In the study, researchers extracted white cells from patients, armed them with pieces of HER2/neu protein, then injected them into 27 patients with HER2-positive ductal carcinoma in situ. Each patient was injected four times over a period of four weeks, with surgery afterward that aimed at removing any remaining cancerous tissue.
Study leader Dr. Brian Czerniecki said the immune systems of 5 of the patients evidently wiped out all signs of the disease, with HER2 expression eliminated in 11 patients and significantly reduced in two others. And Czerniecki says the same pattern is apparent in the second study.
"I think these data more than prove that vaccination works in situations where the target is right," says the scientist, according to a story in The Telegraph. "Previous vaccines targeted tissue antigens that were expressed on the cancer cells, but were not necessary for tumor survival. So a vaccine response would cause the tumor to just stop expressing the antigen and the tumor would be fine. Here we are going after HER2/neu, which is critical for survival of early breast cancers. If we knock it out with the immune response, we cripple the tumor cells."