Vaccine against prostate cancer

Vaccination heals prostate cancer: New vaccine to completely destroy prostate cancer

20.06.2011

Researchers have succeeded in completely destroying prostate tumors using a novel vaccine. The vaccine could potentially serve as an effective weapon in the fight against prostate cancer in the future, write Richard Vile of the Mayo Clinic in Rochester, USA, and Alan Melcher of the University of Leeds, UK in the current issue of the journal „Nature Medicine“.

Researchers have successfully tested a new vaccine on mice that has been used to stimulate the animals' immune responses to completely kill prostate tumors. By injecting genetically modified viruses, the body's own immune system could be stimulated in such a way that a massive reaction of the immune system was triggered and the cancer cells were killed. Other healthy cells, on the other hand, were spared and side effects hardly occurred, according to the US and British researchers. Richard Vile and Alan Melcher hope to be able to use the novel vaccine against other cancers in the future, because the basic principle of activation of the immune system should also be effective in these.

Immunotherapy in action against cancer
Cancer research has long been concerned with the possibilities of tumor control by activating the body's own defenses in the context of immunotherapy. So far, always specifically targeted antigens have been used as a vaccine. In the use of immunotherapy for the treatment of tumors, these were so far mostly surface proteins of the cancer cells, which should trigger increased immune system reactions in an injection. However, the reaction was generally insufficient to completely destroy the cancer cells, reports Vile and Melcher in the journal „Nature Medicine“. Therefore, the British and American researchers have jointly developed a new vaccine that contains, among other things, genetically modified viruses that transport numerous antigens of the prostate cancer cells into the organism. As with a viral infection follows a corresponding defense reaction of the immune system. The fact that the new vaccine contained not just one protein but almost all the antigens of the cancer cells, different variants of immune cells were activated and achieved a significant increase in immunotherapy effectiveness, the researchers report.

Vaccine viruses for the treatment of cancer
Their study on the effect of the new vaccine in the treatment of prostate cancer has shown that repeated injections of the genetically modified virus into the bloodstream produced the best results in mice, write Alan Melcher and Richard Vile. If complete destruction of the prostate gland could not be achieved after the first treatment, a second treatment with a similarly constructed vaccine was carried out, whereby the last surviving cancer cells were finally killed, the researchers report. In addition, no significant side effects were recorded in their investigations, the experts say. Healthy cells remained intact and the initially feared overreaction of the immune system had not occurred in any of the animals. Although must „The vaccine will be further developed and tested in humans before we can say whether this technique will one day be used to treat cancer patients“, commented Peter Johnson from the Institute of Cancer Research London „Nature Medicine“-Items. But Richard Vile showed up „optimistic that we have now overcome some of the major problems that cancer research has seen with immunotherapy“. The researchers hope to begin investigating the vaccine in clinical trials over the next two years. If they are successful, the so-called vaccine viruses could be used in the future also in the treatment of other forms of cancer, so the conclusion of Melcher and Vile. (Fp)

Image: Viktor Mildenberger