Scientists identify genetic faults behind rare prostate cancer

In collaboration with the Press Association

US researchers have uncovered genetic faults behind a rare but particularly aggressive type of prostate cancer, and shown that a drug that's already in clinical trials could be used to treat men with the disease.

Reporting their findings in the journal Cancer Discovery, the experts at Weill Cornell Medical College said the investigational aurora kinase (AURKA) inhibitor PHA-739358 slowed the growth of neuroendocrine prostate tumours in mice.

They found that the genes AURKA and MYCN were more active in the majority of neuroendocrine prostate tumours. And 40 per cent of neuroendocrine prostate cancers and in five per cent of prostate adenocarcinomas - the most common form of the disease - had extra copies of these genes.

Professor Mark Rubin and his team profiled samples of seven neuroendocrine prostate cancers, 30 prostate adenocarcinomas and five samples of healthy prostate tissue.

He said although fewer than two per cent of men with prostate cancer present with the neuroendocrine variety, the more common prostate adenocarcinoma can also evolve into a neuroendocrine prostate cancer during hormone therapy.

Although many men who eventually die of advanced prostate cancer are treated with hormone therapy, it's difficult at the moment to know how many of these men develop neuroendocrine tumours as their disease progressed.

In mice, PHA-739358 shrank large tumours to very small sizes in a short period of time, compared with untreated mice, and the researchers are optimistic that the results may be replicated in humans.

Speaking about his study into neuroendocrine cancers, Dr Rubin added: "This is a highly lethal form of prostate cancer. It is also rare enough that it's hard to get samples. This study is the largest of its kind, and it shows that we may be able to treat this highly aggressive disease."

Himisha Beltran, assistant professor of medicine at Weill, is now preparing for a clinical trial of the drug on prostate cancer patients whose tumours contain neuroendocrine cancer cells.

Dr Laura McCallum, science communication officer at Cancer Research UK, said: "The revolution in DNA sequencing technology has opened up amazing new possibilities for today's scientists - revealing new faults in the genetic make-up of cancers.

"This is early-stage work, but could one day lead to more effective ways to detect and treat this rare but aggressive form of prostate cancer. The next step will be to see whether these drugs work in clinical trials."

Copyright Press Association 2011

References

  • Beltran, H. et al. (2011). Molecular Characterization of Neuroendocrine Prostate Cancer and Identification of New Drug Targets Cancer Discovery 1, 487-495 DOI: 10.1158/2159-8290.CD-11-0130