Scientists have hailed a "substantial advance" for prostate cancer care after they found that a targeted drug may benefit more patients than previously thought. So-called PARP inhibitor drugs can be given as a treatment for men with prostate cancers caused by BRCA1 and BRCA2 genetic mutations. But the new study from the Institute for Cancer Research in London (ICR) suggests that more patients without these mutations may benefit.
Researchers set out to examine the effect of these drugs on men with advanced prostate cancer who have lost the DNA repair protein RNASEH2B in some of their cancer cells. By examining biopsies taken from 124 men with advanced prostate cancer, they found that this protein loss, also known as a genetic aberration, was "common" - found in around 44% of samples studied. Researchers also discovered that a small number of patients with RNASEH2B loss who were treated with a type of PARP inhibitor called olaparib appeared to have months of relapse-free survival, despite not having a BRCA1/2 mutation.
"Further studies are urgently required to validate these findings and extend the utility of PARP (inhibitors)," the authors wrote in the Journal of Clinical Investigation. Nonetheless, they said their finding was a "substantial advance" and said that PARP inhibitor drugs, which come as a pill and have fewer side effects than chemotherapy, may be a treatment option for a wider group of men in the future. Professor Johann de Bono, regius professor of cancer researc.
