Read by QxMD icon Read

Androgen receptor splice variants

Ryuji Yamamoto, Tsuyoshi Osawa, Yusuke Sasaki, Shogo Yamamoto, Motonobu Anai, Kouji Izumi, Yoshihiro Matsumura, Juro Sakai, Hiroyuki Aburatani, Atsushi Mizokami, Tatsuhiko Kodama, Toshiya Tanaka
The non-POU domain-containing octamer binding protein p54nrb /NONO is a multifunctional nuclear protein involved in RNA splicing, processing, and transcriptional regulation of nuclear hormone receptors. Through chromosome copy number analysis via whole-exome sequencing, we revealed amplification of the chromosome Xq11.22-q21.33 locus containing the androgen receptor ( AR ) and NONO genes in androgen-independent, castration-resistant prostate cancer (CRPC)-like LNCaP-SF cells. Moreover, NONO was frequently amplified and overexpressed in patients with CRPC...
February 13, 2018: Oncotarget
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
Ellen Heitzer, Michael R Speicher
<b/> In this issue of Cancer Discovery , Miyamoto and colleagues adapted their microfluidic CTC-iChip isolation platform with a digital RNA-PCR readout for eight prostate-specific transcripts and two assays for the androgen receptor mRNA splice variant ARV7 and the TMPRSS2-ERG translocation transcript. In patients with metastatic castrate-resistant prostate cancer at initiating abiraterone therapy in a first-line setting, the resulting RNA-based digital circulating tumor cell signatures identified patients with a shorter overall survival, and in patients with clinically localized disease, the signatures identified those with seminal vesicle invasion and pelvic lymph node involvement...
March 2018: Cancer Discovery
Yusuke Ito, Marianne D Sadar
Enzalutamide is a nonsteroidal antiandrogen for the treatment of metastatic castration-resistant prostate cancer (mCRPC) both before and after chemotherapy. Enzalutamide is more effective than its predecessor bicalutamide, which was analyzed in head-to-head studies of patients with CRPC. This family of nonsteroidal antiandrogens is now comprised of four drugs approved by the US Food and Drug Administration with two investigational drugs in clinical trials. Antiandrogens have been employed clinically for more than five decades to provide a rich resource of information...
2018: Research and Reports in Urology
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
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
Hiroyuki Ono, Hirotomo Saitsu, Reiko Horikawa, Shinichi Nakashima, Yumiko Ohkubo, Kumiko Yanagi, Kazuhiko Nakabayashi, Maki Fukami, Yasuko Fujisawa, Tsutomu Ogata
Although partial androgen insensitivity syndrome (PAIS) is caused by attenuated responsiveness to androgens, androgen receptor gene (AR) mutations on the coding regions and their splice sites have been identified only in <25% of patients with a diagnosis of PAIS. We performed extensive molecular studies including whole exome sequencing in a Japanese family with PAIS, identifying a deep intronic variant beyond the branch site at intron 6 of AR (NM_000044.4:c.2450-42 G > A). This variant created the splice acceptor motif that was accompanied by pyrimidine-rich sequence and two candidate branch sites...
February 2, 2018: Scientific Reports
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
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
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
Nancy L Goicochea, Maria Garnovskaya, Mary G Blanton, Grace Chan, Richard Weisbart, Michael B Lilly
Castration-resistant prostate cancer cells exhibit continued androgen receptor signaling in spite of low levels of ligand. Current therapies to block androgen receptor signaling act by inhibiting ligand production or binding. We developed bispecific antibodies capable of penetrating cells and binding androgen receptor outside of the ligand-binding domain. Half of the bispecific antibody molecule consists of a single-chain variable fragment of 3E10, an anti-DNA antibody that enters cells. The other half is a single-chain variable fragment version of AR441, an anti-AR antibody...
December 1, 2017: Protein Engineering, Design & Selection: PEDS
Zoran Culig
Purpose of Review: Compensatory mechanisms leading to increased androgen receptor expression and activity after androgen ablation or anti-androgen treatment have been identified in prostate cancer. After hydroxyflutamide and bicalutamide were used in therapy of prostate cancer over many years, novel anti-androgen enzalutamide showed improved clinical activity. However, enzalutamide resistance develops over a certain time period, and molecular mechanisms responsible for this process are heterogeneous...
2017: Current Molecular Biology Reports
Carolina Frankl-Vilches, Manfred Gahr
Singing of songbirds is sensitive to testosterone and its androgenic and estrogenic metabolites in a species-specific way. The hormonal effects on song pattern are likely mediated by androgen receptors (AR) and estrogen receptor alpha (ERα), ligand activated transcription factors that are expressed in neurons of various areas of the songbirds' vocal control circuit. The distribution of AR in this circuit is rather similar between species while that of ERα is species variant and concerns a key vocal control area, the HVC (proper name)...
January 2018: Journal of Comparative Physiology. A, Neuroethology, Sensory, Neural, and Behavioral Physiology
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
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
Keith H K Wong, Shannon N Tessier, David T Miyamoto, Kathleen L Miller, Lauren D Bookstaver, Thomas R Carey, Cleo J Stannard, Vishal Thapar, Eric C Tai, Kevin D Vo, Erin S Emmons, Haley M Pleskow, Rebecca D Sandlin, Lecia V Sequist, David T Ting, Daniel A Haber, Shyamala Maheswaran, Shannon L Stott, Mehmet Toner
Precise rare-cell technologies require the blood to be processed immediately or be stabilized with fixatives. Such restrictions limit the translation of circulating tumor cell (CTC)-based liquid biopsy assays that provide accurate molecular data in guiding clinical decisions. Here we describe a method to preserve whole blood in its minimally altered state by combining hypothermic preservation with targeted strategies that counter cooling-induced platelet activation. Using this method, whole blood preserved for up to 72 h can be readily processed for microfluidic sorting without compromising CTC yield and viability...
November 23, 2017: Nature Communications
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"