An In-Depth Evaluation of the Validity and Logistics Surrounding the Testing of AR-V7 mRNA Expression in Circulating Tumor Cells

Publication date: May 2018Source: The Journal of Molecular Diagnostics, Volume 20, Issue 3Author(s): Anieta M. Sieuwerts, Bianca Mostert, Michelle van der Vlugt-Daane, Jaco Kraan, Corine M. Beaufort, Mai Van, Wendy J.C. Prager, Bram De Laere, Nick Beije, Paul Hamberg, Hans M. Westgeest, Metin Tascilar, Luc Y. Dirix, Wendy Onstenk, Ronald de Wit, Martijn P. Lolkema, Ron H.J. Mathijssen, John W.M. Martens, Stefan SleijferRecent reports have emphasized the clinical relevance of detecting AR-V7 in circulating tumor cells (CTCs). Our aim was to set up a validated multicenter pipeline to measure AR-V7 by quantitative RT-PCR (RT-qPCR) in RNA isolated from CellSearch-enriched CTCs to provide an AR-V7–positive or AR-V7–negative score in a clinically acceptable time range. CellSearch-enirched CTCs from patients with metastatic castration–resistant prostate cancer were characterized by RT-qPCR. After optimization, it was prospectively tested whether it was possible to report the AR-V7 status within 11 days (PRELUDE study). In the range of the RNA equivalent of 0.2 to 12 VCaP cells, the CV for AR-V7 was 9% (n = 37). The limit of detection was 0.3, and the limit of quantitation was 3 cells in the final RT-qPCR. No differences were observed between AR-V7 data generated by five technicians or in two different laboratories. For the 45 patients in PRELUDE, 13 patients were ineligible, 22 patients were AR-V7 negative, and 10 were AR-V7 positive. The median time to inform the physician ...
Source: The Journal of Molecular Diagnostics - Category: Pathology Source Type: research