A new class of cancer drug can help men with aggressive prostate cancer that has stopped responding to conventional treatment, according to a new study.
Researchers found that the drugs, called Hsp90 inhibitors, specifically target and inactivate a mechanism commonly used by prostate cancer cells to evade the effects of standard treatment.
The Institute of Cancer Research findings provide vital information about the role of Hsp90 in drug-resistant prostate cancers, and open up potential new routes to cancer treatment based on blocking this or related proteins.
The team found that Hsp90 inhibitors countered the effect of malfunctions in the androgen receptor, which often occur in resistance to hormone treatments.
By destroying several cancer signals at once, they are designed to make it hard for cancers to escape the effects of treatment, giving them promise as potential 'resistance-busting' drugs.
The new research found that on top of their known effects on cancer, Hsp90 inhibition also blocked production of abnormal forms of the androgen receptor, stripping cancer cells of their defences against hormone treatments.
Study co-leader Paul Workman said, "We call Hsp90 inhibitors 'network drugs' because they tackle several of the signals that are hijacked in cancer all at once, across a network rather than just a single signalling pathway. These drugs can hit cancer harder than those targeting only one protein, and look promising for preventing or overcoming drug resistance."
Study co-leader Johann de Bono said, "These drugs are already in clinical trials for several types of cancer, and I am excited that our work suggests they could also benefit men with prostate cancer who have otherwise run out of treatment options."
The study is published in the journal Cancer Research.
