New drug enables better treatment for aggressive prostate cancer

New drug enables better treatment for aggressive prostate cancer

Drug can overcome drug resistance from some prostate cancer diseases
Prostate cancer is a disease that threatens many older men worldwide. Scientists have now found that men with aggressive prostate cancer may benefit from conventional treatment. A drug that is typically used to overcome drug resistance could now be the new hope for patients with aggressive prostate cancer. The drugs are called Hsp90 inhibitors.

Scientists from the Institute of Cancer Research have now found that Hsp90 inhibitors provide better treatment for aggressive prostate cancer. The medication can overcome existing drug resistance in conventional treatments. The researchers report on their results in a current press release.

Treatment of resistant prostate cancer possible?
Prostate cancer threatens the lives of countless people worldwide. It is one of the most common forms of cancer in men. The disease is the third most common fatal cancer worldwide after lung and colon cancer. In the early stages, prostate cancer is still asymptomatic. In the advanced stage, symptoms such as bone pain, urination problems, later weight loss and anemia can occur, the experts say. Scientists have now found that drug-resistant prostate cancer can be treated with Hsp90 inhibitors. The drug has the potential to develop new ways of treating prostate cancer, the scientists explain.

Prostate cancer disrupts our androgen receptors
The treatment of aggressive prostate cancer sometimes causes androgen receptor disorders, which then lead to resistance to hormone treatments, the authors say. Hsp90 inhibitors could still allow treatment in such a resistant body. Hsp90 inhibitors are among the newly developed drugs that can indirectly treat cancer, the doctors explain. To do this, they destabilize several proteins that are responsible for the growth and survival of cancer cells. By destroying multiple cancer signals at once, it will be difficult for the cancer to escape treatment, the doctors add. The tumors that occur in prostate cancer require androgens to grow. Cancer cells often produce abnormal forms of androgen receptors. These then continuously release androgens all the time. Blocking the androgen receptors could enable effective treatment of the cancer here, the experts say.

When conventional therapies no longer respond
In their study, the researchers examined the inhibitory effects of Hsp90 on human cancer cells, which are most often produced by the androgen receptors. These are called AR-V7. AR-V7-producing androgen receptors were injected into mice in a test. Hsp90 was able to reduce the production of AR-V7, the doctors say. It also reduced the levels of normal androgen receptors and other molecules important for prostate cancer called AKT and GR. Hsp90 inhibitors can block multiple signals caused by cancer at the same time, not just a single pathway, explains co-author Professor Paul Workman of the Institute of Cancer Research. The drug fights cancer more reliably because it cannot block just one protein. In addition, it is extremely promising for the prevention and overcoming of drug resistance, the author adds. Hsp90 enabled treatment of patients who otherwise no longer responded to therapy.

We have shown for the first time that Hsp90 inhibitors block the production of the most common abnormal androgen receptors. These help cancer to spread and stop responding to treatments used, says Professor Johann de Bono from the Institute of Cancer Research. The drugs are already undergoing clinical trials for various types of cancer, and the researchers were enthusiastic that they could also benefit from men with prostate cancer, who otherwise seem to have no treatment options. (as)

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Video: New Treatments for Advanced Prostate Cancer - by Assoc. Prof. Manish Patel - 24 October 2011