Oestrogen signalling pathways are important in about half of all prostate cancers
New US research suggests that that pathways driven by one receptor (ER beta) for oestrogen, the female sex hormone, help to drive an aggressive form of prostate cancer and may therefore provide a new target for drug treatment in around half of all cases of the disease.
Male hormones are already known to drive some prostate cancers and provide a target for many first-line treatments against the disease.
However, the disease often progresses despite such treatments and the latest finding may provide one reason for this.
Researchers at New York Presbyterian Hospital and the Weill Cornell Medical Centre analysed 455 prostate cancer samples from the US and Sweden using an innovative technique to analyse the genes within prostate cancer samples.
After analysing information on more than 6,000 genes in each sample, the researchers discovered that oestrogen-dependent pathways appear to play a crucial role in driving this aggressive form of prostate cancer.
This form of the disease is caused by a genetic error which results in the fusion of two genes.
Study author Dr Mark Rubin, professor of pathology and laboratory medicine at Weill Cornell Medical College, said: "Fifty per cent of prostate cancers harbour a common recurrent gene fusion, and we believe that this confers a more aggressive nature to these tumours.
"Interfering with this gene fusion - or its downstream molecular pathways - will be crucial in the search for drugs that fight the disease. Based on our new data, we now believe that inhibiting oestrogen may be one way of doing so.
"We now believe that agents that dampen oestrogen activity (ER-beta antagonists) could inhibit fusion-positive prostate cancers. Alternatively, any intervention that boosts oestrogen activity (ER-alpha) might also give a boost to these aggressive malignancies."
Henry Scowcroft, a science information manager at Cancer Research UK, said: "Although these results need to be verified by looking at more prostate cancer samples, this is a potentially exciting discovery. Targeting oestrogen signalling has had a huge impact on breast cancer survival rates. This finding raises the tantalising possibility thatsimilar drugs could be used to treat a subset of men with prostate cancer, a disease which kills around ten thousand men a year in the UK alone."
The findings are published in the Journal of the National Cancer Institute.