AUA 2017: Androgen receptor splice variant 7 (AR-V7) in patients with locally advanced, metastatic, and metastatic castration-resistant prostate cancer: a novel capillary nano-immunoassay technique

Boston, MA (UroToday.com) In this session, Dr. Rodriguez and colleagues aimed to investigate the feasibility of a novel capillary nan-immunoassay in detecting AR-V7 variant in plasma from prostate cancer patients. The AR-V7 splice variant has been associated with differences in response of prostate cancer to systemic treatment.

A total of 72 patients with localized, locally advanced, hormone-sensitive metastatic, and metastatic castration-resistant prostate cancer were included. PSA median was 23 (range 0.04-3160). Capillary electrophoresis with immunoassay methodology was performed on patient plasma samples and prostate cancer cell lines using AR-V7 as the primary antibody. Quantitative analysis for AR-V7 protein peak was done as area under the peak.

AR-V7 signal was detected in 21 (29%) of patients; most had Gleason sum of 7 or higher (81%) and castration-resistant prostate cancer (71%). Moreover, AR-V7 positivity was more common in bone (33%) and visceral (28%) metastases.

In conclusion, this study demonstrates that detection of AR-V7 expression from plasma of prostate cancer patients by using an automate capillary nano-immunoassay technique. AR-V7 was more common in aggressive tumors. The authors believe that these data may be able to stratify patients who will respond to systemic therapy and can be used to prevent receipt of inefficient therapies.

Presented By: Alvaro J. Rodriguez, MD

Written By: Benjamin T. Ristau, MD, Fox Chase Cancer Center, Philadelphia, PA

at the 2017 AUA Annual Meeting - May 12 - 16, 2017 – Boston, Massachusetts, USA