Read by QxMD icon Read


Takatsugu Okegawa, Naoki Ninomiya, Kazuki Masuda, Yu Nakamura, Mitsuhiro Tambo, Kikuo Nutahara
OBJECTIVE: We examined whether androgen receptor splice variant 7 (AR-V7) in circulating tumor cell(CTC)clusters can be used to predict survival in patients with bone metastatic castration resistant-prostate cancer (mCRPC) treated with abiraterone or enzalutamide. METHODS: We retrospectively enrolled 98 patients with CRPC on abiraterone or enzalutamide, and investigated the prognostic value of CTC cluster detection (+ v -) and AR-V7 detection (+ v -) using a CTC cluster detection - based AR-V7 mRNA assay...
March 5, 2018: Prostate
Anieta M Sieuwerts, Bianca Mostert, Michelle van der Vlugt-Daane, Jaco Kraan, Corine 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 Sleijfer
Recent reports have emphasized the clinical relevance of detecting the androgen receptor splice variant 7 (AR-V7) in circulating tumor cells (CTCs). Our aim was to set up a validated multicenter pipeline to measure AR-V7 by RT-qPCR in RNA isolated from CellSearch-enriched CTCs to provide an AR-V7 positive/negative score in a clinically acceptable time range. CellSearch-enirched CTCs from metastatic castration-resistant prostate cancer patients 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)...
February 20, 2018: Journal of Molecular Diagnostics: JMD
Nicola Aceto, Aditya Bardia, Ben S Wittner, Maria C Donaldson, Ryan O'Keefe, Amanda Engstrom, Francesca Bersani, Yu Zheng, Valentine Comaills, Kira Niederhoffer, Huili Zhu, Olivia MacKenzie, Toshi Shioda, Dennis Sgroi, Ravi Kapur, David T Ting, Beverly Moy, Sridhar Ramaswamy, Mehmet Toner, Daniel A Haber, Shyamala Maheswaran
Molecular drivers underlying bone metastases in human cancer are not well understood, in part due to constraints in bone tissue sampling. Here, RNA sequencing (RNA-seq) was performed of circulating tumor cells (CTCs) isolated from blood samples of women with metastatic estrogen receptor (ER)+ breast cancer, comparing cases with progression in bone versus visceral organs. Among the activated cellular pathways in CTCs from bone-predominant breast cancer is androgen receptor (AR) signaling. AR gene expression is evident, as is its constitutively active splice variant AR-v7...
February 16, 2018: Molecular Cancer Research: MCR
Takuma Uo, Stephen R Plymate, Cynthia C Sprenger
The androgen receptor variant AR-V7 is gaining attention as a potential predictive marker for as well as one of the resistance mechanisms to the most current anti-androgen receptor (AR) therapies in castration-resistant prostate cancer (CRPC). Accordingly, development of next-generation drugs that directly or indirectly target AR-V7 signaling is urgently needed. Areas covered: We review proposed mechanisms of drug resistance in relation to AR-V7 status, the mechanisms of generation of AR-V7, and its transcriptome, cistrome, and interactome...
February 8, 2018: Expert Opinion on Therapeutic Targets
Sarah Q To, Edmond M Kwan, Heidi C Fettke, Andrew Mant, Maria M Docanto, Luciano Martelotto, Patricia Bukczynska, Nicole Ng, Lisa-Jane K Graham, Phillip Parente, Carmel Pezaro, Kate Mahon, Lisa Horvath, Tilman Todenhöfer, Arun A Azad
In 2014, a landmark study was published demonstrating that the expression of androgen receptor splice variant (AR-V) 7 was a negative predictive biomarker for response to abiraterone acetate and enzalutamide in metastatic castration-resistant prostate cancer (mCRPC) patients. However, these results were not supported by the recently reported ARMOR3-SV phase III clinical trial, which employed an identical circulating tumour cell assay to assess AR-V7 expression. Therefore, the predictive utility of AR-V7 expression in mCRPC remains uncertain, as does any potential association between other AR-Vs and treatment response...
February 2, 2018: European Urology
Michael I Koukourakis, Christos Kakouratos, Dimitra Kalamida, Achilleas Mitrakas, Stamatia Pouliliou, Erasmia Xanthopoulou, Evdokia Papadopoulou, Virginia Fasoulaki, Alexandra Giatromanolaki
Apalutamide (ARN-509) is an antiandrogen that binds selectively to androgen receptors (AR) and does not show antagonist-to-agonist switch like bicalutamide. We compared the activity of ARN versus bicalutamide on prostate cancer cell lines. The 22Rv1, PC3, and DU145 cell lines were used to study the effect of ARN and bicalutamide on the expression cytoplasmic/nuclear kinetics of AR, AR-V7 variant, phosphorylated AR, as well as the levels of the AR downstream proteins prostate-specific antigen and TMPRSS2, under exposure to testosterone and/or hypoxia...
January 29, 2018: Anti-cancer Drugs
P Thelen, H Taubert, S Duensing, G Kristiansen, A S Merseburger, M V Cronauer
A recently discovered mechanism enabling prostate cancer cells to escape the effects of endocrine therapies consists in the synthesis of C-terminally truncated, constitutively active androgen receptor (AR) splice variants (AR-V). Devoid of a functional C-terminal hormone/ligand binding domain, various AR-Vs are insensitive to therapies targeting the androgen/AR signalling axis. Preliminary studies suggest that AR-V7, the most common AR-V, is a promising predictive tumour marker and a relevant selection marker for the treatment of advanced prostate cancer...
January 25, 2018: Aktuelle Urologie
Christof Bernemann, Julie Steinestel, Verena Humberg, Martin Bögemann, Andres Jan Schrader, Jochen K Lennerz
OBJECTIVES: To compare the performance of two established androgen receptor splice variant 7 (AR-V7) mRNA detection systems, as paradoxical responses to next-generation androgen-deprivation therapy in AR-V7 mRNA-positive circulating tumour cells (CTC) of patients with castration-resistant prostate cancer (CRPC) could be related to false-positive classification using detection systems with different sensitivities. MATERIALS AND METHODS: We compared the performance of two established mRNA-based AR-V7 detection technologies using either SYBR Green or TaqMan chemistries...
January 23, 2018: BJU International
Vidya P Ramamurthy, Senthilmurugan Ramalingam, Lalji K Gediya, Vincent C O Njar
VNLG-152, a lead novel retinamide (NR) shown to suppress growth and progression in genetically diverse PCa cells via inhibition of AR signaling and eIF4E translational machinery. Herein, we report therapeutic effects of VNLG-152 on castration resistant prostate cancer (CRPC) growth and metastatic phenotype in CRPC tumor xenograft model. Administration of VNLG-152 significantly and dose-dependently suppressed the growth of aggressive CWR22Rv1 tumors by 63.4% and 76.3% respectively (P = 0.001), vs. vehicle with no host toxicity...
January 11, 2018: FEBS Journal
Diogo A Bastos, Emmanuel S Antonarakis
Prostate cancer is a highly heterogeneous disease, with remarkably different prognosis across all stages. Increased circulating tumor cell (CTC) count (≥ 5) using the CellSearch assay has been identified as one of the markers that can be used to predict survival, with added value beyond currently available prognostic factors. Recently, androgen receptor splice variant 7 (AR-V7) detection has been associated with worse outcomes for patients with castration-resistant prostate cancer (CRPC) treated with novel androgen receptor-signaling (ARS) inhibitors such as abiraterone and enzalutamide but not taxane chemotherapies...
January 10, 2018: Expert Review of Molecular Diagnostics
Amin El-Heliebi, Claudia Hille, Navya Laxman, Jessica Svedlund, Christoph Haudum, Erkan Ercan, Thomas Kroneis, Shukun Chen, Maria Smolle, Christopher Rossmann, Tomasz Krzywkowski, Annika Ahlford, Evangelia Darai, Gunhild von Amsberg, Winfried Alsdorf, Frank König, Matthias Löhr, Inge de Kruijff, Sabine Riethdorf, Tobias M Gorges, Klaus Pantel, Thomas Bauernhofer, Mats Nilsson, Peter Sedlmayr
BACKGROUND: Liquid biopsies can be used in castration-resistant prostate cancer (CRPC) to detect androgen receptor splice variant 7 (AR-V7), a splicing product of the androgen receptor. Patients with AR-V7-positive circulating tumor cells (CTCs) have greater benefit of taxane chemotherapy compared with novel hormonal therapies, indicating a treatment-selection biomarker. Likewise, in those with pancreatic cancer (PaCa), KRAS mutations act as prognostic biomarkers. Thus, there is an urgent need for technology investigating the expression and mutation status of CTCs...
January 4, 2018: Clinical Chemistry
David T Miyamoto, Richard J Lee, Mark Kalinich, Joseph LiCausi, Yu Zheng, Tianqi Chen, John D Milner, Erin Emmons, Uyen Ho, Katherine Broderick, Erin Silva, Sarah Javaid, Tanya Todorova Kwan, Xin Hong, Douglas M Dahl, Francis J McGovern, Jason A Efstathiou, Matthew R Smith, Lecia V Sequist, Ravi Kapur, Chin-Lee Wu, Shannon L Stott, David T Ting, Anita Giobbie-Hurder, Mehmet Toner, Shyamala Maheswaran, Daniel A Haber
Blood-based biomarkers are critical in metastatic prostate cancer, where characteristic bone metastases are not readily sampled, and they may enable risk stratification in localized disease. We established a sensitive and high-throughput strategy for analyzing prostate circulating tumor cells (CTCs) using microfluidic cell enrichment followed by digital quantitation of prostate-derived transcripts. In a prospective study of 27 metastatic castration-resistant prostate cancer patients treated with first-line abiraterone, pretreatment elevation of the digital CTCM Score identifies a high risk population with poor overall survival (HR 6...
January 4, 2018: Cancer Discovery
Jun Luo, Gerhardt Attard, Steven P Balk, Charlotte Bevan, Kerry Burnstein, Laura Cato, Artem Cherkasov, Johann S De Bono, Yan Dong, Allen C Gao, Martin Gleave, Hannelore Heemers, Mayuko Kanayama, Ralf Kittler, Joshua M Lang, Richard J Lee, Christopher J Logothetis, Robert Matusik, Stephen Plymate, Charles L Sawyers, Luke A Selth, Howard Soule, Wayne Tilley, Nancy L Weigel, Amina Zoubeidi, Scott M Dehm, Ganesh V Raj
CONTEXT: Although a number of studies have demonstrated the importance of constitutively active androgen receptor variants (AR-Vs) in prostate cancer, questions still remain about the precise role of AR-Vs in the progression of castration-resistant prostate cancer (CRPC). OBJECTIVE: Key stakeholders and opinion leaders in prostate cancer convened on May 11, 2017 in Boston to establish the current state of the field of AR-Vs. EVIDENCE ACQUISITION: The meeting "Mission Androgen Receptor Variants" was the second of its kind sponsored by the Prostate Cancer Foundation (PCF)...
December 16, 2017: European Urology
Sue Jin Moon, Byong Chang Jeong, Hwa Jin Kim, Joung Eun Lim, Ghee Young Kwon, Jeong Hoon Kim
Constitutively active AR-V7, one of the major androgen receptor (AR) splice variants lacking the ligand-binding domain, plays a key role in the development of castration-resistant prostate cancer (CRPC) and anti-androgen resistance. However, our understanding of the regulatory mechanisms of AR-V7-driven transcription is limited. Here we report DBC1 as a key regulator of AR-V7 transcriptional activity and stability in CRPC cells. DBC1 functions as a coactivator for AR-V7 and is required for the expression of AR-V7 target genes including CDH2, a mesenchymal marker linked to CRPC progression...
December 18, 2017: Oncogene
Abigail B McLeod, James P Stice, Suzanne E Wardell, Holly M Alley, Ching-Yi Chang, Donald P McDonnell
BACKGROUND: Whereas the androgen receptor (AR) signaling axis remains a therapeutic target in castration-resistant prostate cancer (CRPC), the emergence of AR mutations and splice variants as mechanisms underlying resistance to contemporary inhibitors of this pathway highlights the need for new therapeutic approaches to target this disease. Of significance in this regard is the considerable preclinical data, indicating that histone deacetylase (HDAC) inhibitors may have utility in the treatment of CRPC...
December 15, 2017: Prostate
Xin Chen, Christof Bernemann, Yuri Tolkach, Martina Heller, Cathleen Nientiedt, Michael Falkenstein, Esther Herpel, Maximilian Jenzer, Carsten Grüllich, Dirk Jäger, Holger Sültmann, Anette Duensing, Sven Perner, Marcus V Cronauer, Carsten Stephan, Jürgen Debus, Andres Jan Schrader, Glen Kristiansen, Markus Hohenfellner, Stefan Duensing
BACKGROUND: Overexpression of the androgen receptor (AR) splice variant 7 (AR-V7) has recently been reported to be associated with resistance to antihormonal therapy. Herein, we address the question whether tumor cells with AR-V7 expression can be detected at the time of radical prostatectomy, that is, before long-term hormonal manipulation and castration resistance, and what the potential prognostic impact on the biochemical recurrence (BCR)-free survival may be. METHODS: An anti-AR-V7 antibody was first validated in a training set of prostate cancer specimens by a comparison of AR-V7 protein to AR-V7 mRNA expression...
November 29, 2017: Urologic Oncology
David J McCarty, Weiliang Huang, Maureen A Kane, Puranik Purushottamachar, Lalji K Gediya, Vincent C O Njar
The androgen receptor (AR) has long been the primary target for the treatment of prostate cancer (PC). Despite continuous efforts to block AR activity through ligand depletion, AR antagonism, AR depletion and combinations thereof, advanced PC tumors remain resilient. Herein, we evaluate two galeterone analogs, VNPT-178 and VNLG-74A, in PC cell models of diverse androgen and AR dependence attempting to delineate their mechanisms of action and potential clinical utility. Employing basic biochemical techniques, we determined that both analogs have improved antiproliferative and anti-AR activities compared to FDA-approved abiraterone and enzalutamide...
October 24, 2017: Oncotarget
Mark C Markowski, John L Silberstein, James R Eshleman, Mario A Eisenberger, Jun Luo, Emmanuel S Antonarakis
Purpose: A splice variant of the androgen receptor, AR-V7, confers resistance to AR-targeted therapies (ATTs) but not taxane chemotherapies in patients with metastatic castration-resistant prostate cancer. Since August 2015, a clinical-grade assay to detect AR-V7 messenger RNA expression in circulating tumors cells (CTCs) has been available to providers through a Clinical Laboratory Improvement Amendments-certified laboratory at Johns Hopkins University. Methods: We contacted ordering providers of the first 150 consecutive tests by using a questionnaire-based survey to determine how the results of AR-V7 testing were used to influence clinical practice...
2017: JCO Precision Oncology
Megan Crumbaker, Richard Savdie, Anthony M Joshua
No abstract text is available yet for this article.
November 18, 2017: European Urology
Maryam Ghashghaei, Miltiadis Paliouras, Mitra Heravi, Hamed Bekerat, Mark Trifiro, Tamim M Niazi, Thierry Muanza
BACKGROUND: Prostate cancer (PCa) is a progressive disease and the most diagnosed cancer in men. The current standard of care for high-risk localized PCa is a combination of androgen deprivation therapy (ADT) and radiation (XRT). The majority of these patients however become resistant due to incomplete responses to ADT as a result of selective cells maintaining androgen receptor (AR) activity. Improvement can be made if increasing radiosensitivity is realized. Therefore, the aim of this study is to investigate the efficacy of the next-generation PCa drug Enzalutamide (ENZA), as a radiosensitizer in XRT therapy...
January 2018: Prostate
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"