Dr. Stein on AR-Resistance in Prostate Cancer

Mark Stein, MD, medical oncologist, Rutgers Cancer Institute of New Jersey, discusses androgen receptor (AR)—resistance in prostate cancer.

One lingering question in this space is whether or not these splice variants always exist at low levels in prostate cancer. According to Stein, the answer is that the splice variants are, indeed, always there, but it is not completely understood as to why they are there. The full-length AR is the majority of the androgen receptor in the cell, but not all of it, he explains. Under selective pressure, cells proliferate that are able to adapt to the presence of an AR-inhibitor, such as enzalutamide (Xtandi).

Stein says it is also interesting that, if a patient is given another treatment after an AR-inhibitor, such as chemotherapy, one can actually see the levels of the AR variants decreasing, suggesting that, once the selective pressure is removed, that variant goes away.

More remaining questions about AR—resistance in prostate cancer will soon be answered as novel biomarkers are embedded into future clinical trials.