World Journal of Urology

, Volume 35, Issue 10, pp 1625–1627 | Cite as

Novel AR-V7 detection in whole blood samples in patients with prostate cancer: not as simple as it seems

  • Christof BernemannEmail author
  • Julie Steinestel
  • Martin Boegemann
  • Andres J. Schrader
Letter to the Editor

Dear Editor,

Expression of androgen receptor (AR) splice variants in metastatic castration resistant prostate cancer (mCRPC) patients is thought to effectuate resistance to novel hormone therapies (NHT) [1, 2]. Indeed, Antonarakis et al. demonstrated that mCRPC patients expressing AR-V7 in circulating tumor cells (CTCs) did not respond to NHT, i.e. abiraterone or enzalutamide, whereas response to taxane based chemotherapy was not affected [3, 4]. Further studies reinforced the potential of AR-V7 as a treatment selection biomarker [5, 6, 7].

Most approaches to detect AR-V7 in patients’ CTCs need to enrich these cells from the billions of blood cells surrounding CTCs in the blood stream. These techniques need to be applied within a few hours after blood draw to isolate intact RNA for downstream applications. Thus, shipping and subsequent processing of blood samples for global clinical studies are cost intensive and hard to manage within clinical routine. Therefore, an improvement of the...


Abiraterone Enzalutamide Abiraterone Acetate CRPC Patient Metastatic Castration Resistant Prostate Cancer 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2017

Authors and Affiliations

  • Christof Bernemann
    • 1
    Email author
  • Julie Steinestel
    • 1
  • Martin Boegemann
    • 1
  • Andres J. Schrader
    • 1
  1. 1.Clinic of UrologyUniversity HospitalMuensterGermany

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