Exciting Breakthrough: Targeting Neuroendocrine Prostate Cancer

You might think that prostate cancer is one specific disease.  You’d probably be surprised to learn that, in fact,  there are as many as twenty-three different types off prostate cancer. Ninety-five percent of them are referred to as adenocarcinomas; they are most commonly occurring ones. But one you may not have heard about is called neuroendocrine prostate cancer. Neuroendocrine prostate cancer is pretty rare; it occurs in fewer than 2% of prostate tumors and it is a type of prostate cancer that is very tough to treat.  In the Nov 17th issue of Cancer Discovery researchers at Weill Cornell Medical College report that they have found an investigational drug that has had a dramatic response in animal models of neuroendocrine  prostate cancer. It’s an exciting discovery for advanced prostate cancer intervention.

What has made  neuroendocrine prostate cancer so challenging is that, unlike adenocarcinoma types of prostate cancer, this one type does not make PSA. Neuroencocrine cells don’t grow and lack the androgen receptors found in the other types of prostate cells. But they appear to produce hormones that fuel other forms of prostate cancer cells. Attacking them the way doctors attack the majority of other prostate cancer cells simply does not work.  And the bad news is they are found scattered throughout cancer tumors and their role in the biology of the prostate is not yet clearly understood. Surgeons have reported that when they collect prostate cancer specimens after surgery, the ones near neuroendocrine cells grow more rapidly than prostate cancer cells distant from the neuroendocrine variety.  The larger the proportion of a cancer mass composed of neuroendocrine cells the greater the chance the patient will do poorly over time.

The  international team of scientists led by Dr.Mark A. Rubin and his team of researchers at Weill Cornell Medical College has discovered a way to target and destroy neuroendocrine prostate cancer cells. It provides the first hope of an effective an effective human therapy for this lethal form of prostate cancer.

Their approach identified a new molecular target for which a drug is presently available.   Dr. Rubin, a professor  of pathology at Weill Cornell, says the study “ demonstrates that the drug (aurora kinase inhibitor PHA- 739358) worked against human neuroendocrine prostate cells in the lab, and that it had a dramatic response in animal models of neuroendocrine prostate cancer.” He added “we hope to develop biomarkers that can help us screen patients for these cells before the cancer advances.”

To better understand the problem researchers faced, it’s important to know that androgen suppressing drugs, while able to control adenocarcinoma prostate cancers –the most common kind—have had no effect on neuroendocrine cells that may have been part of the tumor mix.  Researchers say that of the nearly 30,000 men who die of advanced prostate cancer every year and who have been treated with androgen suppression therapy, it’s been impossible to tell how many of them developed neuroendocrine tumors.  That’s because patients are not usually biopsied at that late stage of their disease.  Studies to define the changing biology of the prostate cancer cells are just now getting underway.