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Van-Duyne G, Blair IA, Sprenger C, Moiseenkova-Bell V, Plymate S, Penning TM. The androgen receptor. VITAMINS AND HORMONES 2023; 123:439-481. [PMID: 37717994 DOI: 10.1016/bs.vh.2023.01.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/19/2023]
Abstract
The Androgen Receptor (AR) is a ligand (androgen) activated transcription factor and a member of the nuclear receptor (NR) superfamily. It is required for male sex hormone function. AR-FL (full-length) has the domain structure of NRs, an N-terminal domain (NTD) required for transactivation, a DNA-binding domain (DBD), a nuclear localization signal (NLS) and a ligand-binding domain (LBD). Paradoxes exist in that endogenous ligands testosterone (T) and 5α-dihydrotestosterone (DHT) have differential effects on male sexual development while binding to the same receptor and transcriptional specificity is achieved even though the androgen response elements (AREs) are identical to those seen for the progesterone, glucocorticoid and mineralocorticoid receptors. A high resolution 3-dimensional structure of AR-FL by either cryo-EM or X-ray crystallography has remained elusive largely due to the intrinsic disorder of the NTD. AR function is regulated by post-translational modification leading to a large number of proteoforms. The interaction of these proteoforms in multiprotein complexes with co-activators and co-repressors driven by interdomain coupling mediates the AR transcriptional output. The AR is a drug target for selective androgen receptor modulators (SARMS) that either have anabolic or androgenic effects. Protstate cancer is treated with androgen deprivation therapy or by the use of AR antagonists that bind to the LBD. Drug resistance occurs due to adaptive AR upregulation and the appearance of splice variants that lack the LBD and become constitutively active. Bipolar T treatment and NTD-antagonists could surmount these resistance mechanisms, respectively. These recent advances in AR signaling are described.
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Affiliation(s)
- Greg Van-Duyne
- Department of Biophysics & Biochemistry, Perelman School of Medicine University of Pennsylvania, Philadelphia, PA, United States
| | - Ian A Blair
- Department of Systems Pharmacology & Translational Therapeutics, Perelman School of Medicine University of Pennsylvania, Philadelphia, PA, United States
| | - Cynthia Sprenger
- Division of Gerontology & Geriatric Medicine, Department of Medicine, University of Washington and GRECC, Seattle, WA, United States
| | - Vera Moiseenkova-Bell
- Department of Systems Pharmacology & Translational Therapeutics, Perelman School of Medicine University of Pennsylvania, Philadelphia, PA, United States
| | - Stephen Plymate
- Division of Gerontology & Geriatric Medicine, Department of Medicine, University of Washington and GRECC, Seattle, WA, United States
| | - Trevor M Penning
- Department of Systems Pharmacology & Translational Therapeutics, Perelman School of Medicine University of Pennsylvania, Philadelphia, PA, United States.
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2
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Asangani I, Blair IA, Van Duyne G, Hilser VJ, Moiseenkova-Bell V, Plymate S, Sprenger C, Wand AJ, Penning TM. Using biochemistry and biophysics to extinguish androgen receptor signaling in prostate cancer. J Biol Chem 2021; 296:100240. [PMID: 33384381 PMCID: PMC7949100 DOI: 10.1074/jbc.rev120.012411] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2020] [Revised: 12/19/2020] [Accepted: 12/31/2020] [Indexed: 12/12/2022] Open
Abstract
Castration resistant prostate cancer (CRPC) continues to be androgen receptor (AR) driven. Inhibition of AR signaling in CRPC could be advanced using state-of-the-art biophysical and biochemical techniques. Structural characterization of AR and its complexes by cryo-electron microscopy would advance the development of N-terminal domain (NTD) and ligand-binding domain (LBD) antagonists. The structural basis of AR function is unlikely to be determined by any single structure due to the intrinsic disorder of its NTD, which not only interacts with coregulators but likely accounts for the constitutive activity of AR-splice variants (SV), which lack the LBD and emerge in CRPC. Using different AR constructs lacking the LBD, their effects on protein folding, DNA binding, and transcriptional activity could reveal how interdomain coupling explains the activity of AR-SVs. The AR also interacts with coregulators that promote chromatin looping. Elucidating the mechanisms involved can identify vulnerabilities to treat CRPC, which do not involve targeting the AR. Phosphorylation of the AR coactivator MED-1 by CDK7 is one mechanism that can be blocked by the use of CDK7 inhibitors. CRPC gains resistance to AR signaling inhibitors (ARSI). Drug resistance may involve AR-SVs, but their role requires their reliable quantification by SILAC-mass spectrometry during disease progression. ARSI drug resistance also occurs by intratumoral androgen biosynthesis catalyzed by AKR1C3 (type 5 17β-hydroxysteroid dehydrogenase), which is unique in that its acts as a coactivator of AR. Novel bifunctional inhibitors that competitively inhibit AKR1C3 and block its coactivator function could be developed using reverse-micelle NMR and fragment-based drug discovery.
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Affiliation(s)
- Irfan Asangani
- Department Cancer Biology, Perelman School of Medicine University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Ian A Blair
- Department Systems Pharmacology & Translational Therapeutics, Perelman School of Medicine University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Gregory Van Duyne
- Department of Biochemistry & Biophysics, Perelman School of Medicine University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Vincent J Hilser
- Department of Biology, Johns Hopkins University, Baltimore, Maryland, USA
| | - Vera Moiseenkova-Bell
- Department Systems Pharmacology & Translational Therapeutics, Perelman School of Medicine University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Stephen Plymate
- Division of Gerontology & Geriatric Medicine, Department of Medicine, University of Washington, and GRECC, Seattle, Washington, USA
| | - Cynthia Sprenger
- Division of Gerontology & Geriatric Medicine, Department of Medicine, University of Washington, and GRECC, Seattle, Washington, USA
| | - A Joshua Wand
- Department of Biochemistry & Biophysics, Texas A&M University, College Station, Texas, USA
| | - Trevor M Penning
- Department Systems Pharmacology & Translational Therapeutics, Perelman School of Medicine University of Pennsylvania, Philadelphia, Pennsylvania, USA.
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Wang Z, Shen H, Ma N, Li Q, Mao Y, Wang C, Xie L. The Prognostic Value of Androgen Receptor Splice Variant 7 in Castration-Resistant Prostate Cancer Treated With Novel Hormonal Therapy or Chemotherapy: A Systematic Review and Meta-analysis. Front Oncol 2020; 10:572590. [PMID: 33425724 PMCID: PMC7793884 DOI: 10.3389/fonc.2020.572590] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Accepted: 10/07/2020] [Indexed: 12/19/2022] Open
Abstract
Purpose This study aimed to evaluate the prognostic role of AR-V7 in terms of prostate-specific antigen (PSA) response, progression-free survival (PFS), and overall survival (OS) in CRPC patients treated with novel hormonal therapy (NHT) (Abiraterone and Enzalutamide) or taxane-based chemotherapy (Docetaxel and Cabazitaxel). Methods A comprehensive literature search was conducted on PubMed, Embase, and the Web of Science from inception to February 2020. Studies focusing on the prognostic values of AR-V7 in CRPC patients treated with NHT or chemotherapy were included in our meta-analysis. The OS and PFS were analyzed based on Hazard ratios (HRs) and 95% confidence intervals (CIs). Furthermore, Odds ratios (ORs) and 95% CIs were summarized for the AR-V7 conversion after treatment and the PSA response. Results The AR-V7 positive proportion increased significantly after NHT treatment (OR 2.56, 95% CI 1.51–4.32, P<0.001), however, it declined after chemotherapy (OR 0.51, 95% CI 0.28–0.93, P=0.003). AR-V7-positive patients showed a significantly decreased PSA response rate after NHT (OR 0.13, 95% CI 0.09–0.19, P<0.001) but not statistically significant for chemotherapy (OR 0.63, 95% CI 0.40-1.01, P=0.06). Notably, PFS (HR 3.56, 95% CI 2.53–5.01, P<0.001) and OS (HR 4.47, 95% CI 3.03–6.59, P<0.001) were worse in AR-V7-positive ttreated with NHT. Similarly, AR-V7 positivity correlated with poor prognosis after chemotherapy as evidenced by shorter OS (HR 1.98, 95% CI 1.48-2.66, P<0.001) and a significantly shorter PFS (HR 1.35, 95% CI 0.97-1.87, P=0.07). Conclusion NHT treatment increased AR-V7 positive proportion whereas chemotherapy decreased it. Moreover, AR-V7 positivity correlated with lower PSA response, poorer PFS, and OS in CRPC treated with NHT, and shorter OS in patients receiving chemotherapy.
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Affiliation(s)
- Zhize Wang
- Department of Urology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Haixiang Shen
- Department of Urology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Nieying Ma
- Key laboratory of Reproductive Genetic (Ministry of Education) and Department of Reproductive Endocrinology, Women's Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Qinchen Li
- Department of Urology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Yeqing Mao
- Department of Urology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Chaojun Wang
- Department of Urology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Liping Xie
- Department of Urology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
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Kessel K, Seifert R, Weckesser M, Roll W, Humberg V, Schlack K, Bögemann M, Bernemann C, Rahbar K. Molecular analysis of circulating tumor cells of metastatic castration-resistant Prostate Cancer Patients receiving 177Lu-PSMA-617 Radioligand Therapy. Theranostics 2020; 10:7645-7655. [PMID: 32685010 PMCID: PMC7359074 DOI: 10.7150/thno.44556] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Accepted: 05/20/2020] [Indexed: 12/21/2022] Open
Abstract
Rationale: Lu-177-PSMA-617 radioligand therapy (RLT) is currently under approval for treatment of metastatic castration resistant prostate cancer (mCRPC) patients with late stage disease. However, previous studies demonstrated both heterogeneity of prostate specific membrane antigen (PSMA) expression, as well as response to PSMA treatment among mCRPC patients. Thus, there is an unmet need for identifying predictive parametres prior or under PSMA-RLT treatment. We therefore aimed to correlate several clinical and molecular parameters with response to PSMA treatment in a cohort of mCRPC patients undergoing PSMA RLT followed by a detailed analysis of promising candidates. Methods: Nineteen patients, median age 68.8 years (range: 56.9 - 83.3) with mCRPC were included in this study. We performed baseline analysis of clinical parameters based on PSMA PET/CT, (metabolic tumor volume (MTV), total tumor volume (TTV)), serum PSA, ALP, LDH and gene expression analysis of circulating tumor cells (expression of AR full length (AR-FL), AR splice variant 7 (AR-V7), PSA and PSMA) as well as common markers for neuroendocrine differentiation (NED). Results: Patients presented with bone, lymph node, and visceral metastases (89%, 68%, and 21%, respectively). All patients were pretreated with docetaxel, either abiraterone or enzalutamide, or both. Biochemical response in terms of PSA decline ≥50 or ≥30% was observed in 42% and 63%, respectively. There were significant correlations between PSA and PSMA mRNA expression, as well as tumor volumes (both MTV and TTV), AR-FL and AR-V7 mRNA expression. However, there was no correlation with response to PSMA treatment. Furthermore, none of these parameters was significantly correlated with baseline serum PSA values. Common NED markers were shown to be specifically high expressed and revealed impact on OS independent from AR-V7 gene expression. Conclusion: We demonstrate that AR-FL and its splice variant AR-V7 might serve as prognostic biomarkers displaying high tumor burden in mCRPC patient prior to PSMA-RLT. Contrary, PSMA, which has been discussed as a biomarker for PSMA targeted treatment, does not display strong prognostic ability - at least on the mRNA level. Surprisingly, none of these parameters correlates to response to PSMA treatment. In contrast, commom NED markers such as SYP and ENO2 as well as FOXA1 expression level seem to predict OS, but not PFS, more reliably. We admit that a limitation of our study is the focus on mRNA expression of potential biomarkers only. Further investigations analyzing the potential role of protein expression of these markers are therefore warranted.
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Erb HHH, Sparwasser P, Diehl T, Hemmerlein-Thomas M, Tsaur I, Jüngel E, Sommer U, Baretton GB, Haferkamp A, Neisius A, Thomas C. AR-V7 Protein Expression in Circulating Tumour Cells Is Not Predictive of Treatment Response in mCRPC. Urol Int 2020; 104:253-262. [PMID: 31955172 DOI: 10.1159/000504416] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2019] [Accepted: 10/28/2019] [Indexed: 11/19/2022]
Abstract
INTRODUCTION Androgen receptor variant 7 (AR-V7) plays an important role in the progression of castration-resistant prostate cancer (CRPC) and has shown potential as a predictive biomarker in circulating tumour cells (CTCs) isolated from the bloodstream in terms of a liquid biopsy. Studies have shown that AR-V7 is a potential surrogate for selecting drug classes for systemic treatment by detecting nuclear AR-V7 by immunofluorescence or measuring AR-V7 messenger RNA by quantitative PCR. Here, we assessed the predictive value of AR-V7 detected by classical immunohistochemistry (IHC) for treatment response. METHODS CTCs were isolated by cell separation by density gradient centrifugation from patients with metastatic CRPC (n = 26) before, while, and after undergoing a new therapy with chemotherapy (cabazitaxel or docetaxel) or antiandrogen (enzalutamide or abiraterone). CTCs were sequentially cytospun on object slides, and AR-V7 status was then detected by IHC based on a staining regime established on a 22Rv1 cell line with antibodies against CK8/18 und AR-V7. RESULTS AR-V7 status detected by IHC showed no predictive value for progression-free survival (PFS). Kaplan-Meier analysis revealed that there was no difference in PFS between patients found positive or negative for AR-V7. DISCUSSION/CONCLUSION AR-V7 detected by classical IHC has no predictive value for treatment response in the described setting. The future role of AR-V7 in CTCs as a biomarker in clinical routine remains elusive.
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Affiliation(s)
| | - Peter Sparwasser
- Department of Urology and Pediatric Urology, University Medical Center Mainz, Mainz, Germany
| | - Tamara Diehl
- Department of Urology and Pediatric Urology, University Medical Center Mainz, Mainz, Germany
| | | | - Igor Tsaur
- Department of Urology and Pediatric Urology, University Medical Center Mainz, Mainz, Germany
| | - Eva Jüngel
- Department of Urology and Pediatric Urology, University Medical Center Mainz, Mainz, Germany
| | - Ulrich Sommer
- Institute of Pathology, Technische Universität Dresden, Dresden, Germany
| | - Gustavo B Baretton
- Institute of Pathology, Technische Universität Dresden, Dresden, Germany
| | - Axel Haferkamp
- Department of Urology and Pediatric Urology, University Medical Center Mainz, Mainz, Germany
| | - Andreas Neisius
- Department of Urology and Pediatric Urology, University Medical Center Mainz, Mainz, Germany
| | - Christian Thomas
- Department of Urology, Technische Universität Dresden, Dresden, Germany, .,Department of Urology and Pediatric Urology, University Medical Center Mainz, Mainz, Germany,
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Rao A, Antonarakis ES. Circulating tumor cell-based or tissue biopsy-based AR-V7 detection: which provides the greatest clinical utility? ANNALS OF TRANSLATIONAL MEDICINE 2019; 7:S354. [PMID: 32016072 PMCID: PMC6976453 DOI: 10.21037/atm.2019.09.92] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2019] [Accepted: 09/11/2019] [Indexed: 01/10/2023]
Affiliation(s)
- Arpit Rao
- Department of Hematology, Oncology and Transplantation, University of Minnesota Masonic Cancer Center, Minneapolis, Minnesota, USA
| | - Emmanuel S. Antonarakis
- Departments of Oncology and Urology, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
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7
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Bernemann C, Humberg V, Thielen B, Steinestel J, Chen X, Duensing S, Schrader AJ, Boegemann M. Comparative Analysis of AR Variant AR-V567es mRNA Detection Systems Reveals Eminent Variability and Questions the Role as a Clinical Biomarker in Prostate Cancer. Clin Cancer Res 2019; 25:3856-3864. [DOI: 10.1158/1078-0432.ccr-18-4276] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Revised: 03/13/2019] [Accepted: 04/11/2019] [Indexed: 11/16/2022]
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Scher HI, Graf RP, Schreiber NA, Jayaram A, Winquist E, McLaughlin B, Lu D, Fleisher M, Orr S, Lowes L, Anderson A, Wang Y, Dittamore R, Allan AL, Attard G, Heller G. Assessment of the Validity of Nuclear-Localized Androgen Receptor Splice Variant 7 in Circulating Tumor Cells as a Predictive Biomarker for Castration-Resistant Prostate Cancer. JAMA Oncol 2018; 4:1179-1186. [PMID: 29955787 PMCID: PMC6139066 DOI: 10.1001/jamaoncol.2018.1621] [Citation(s) in RCA: 178] [Impact Index Per Article: 29.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Accepted: 03/19/2018] [Indexed: 11/14/2022]
Abstract
Importance A blood test to determine whether to treat patients with metastatic castration-resistant prostate cancer (mCRPC) with an androgen receptor signaling (ARS) inhibitor or taxane is an unmet medical need. Objective To determine whether a validated assay for the nuclear-localized androgen receptor splice variant 7 (AR-V7) protein in circulating tumor cells can determine differential overall survival among patients with mCRPC treated with taxanes vs ARS inhibitors. Design, Setting, and Participants This blinded correlative study conducted from December 31, 2012, to September 1, 2016, included 142 patients with histologically confirmed mCRPC and who were treated at Memorial Sloan Kettering Cancer Center, The Royal Marsden, or the London Health Sciences Centre. Blood samples were obtained prior to administration of ARS inhibitors or taxanes as a second-line or greater systemic therapy for progressing mCRPC. Main Outcomes and Measures Overall survival after treatment with an ARS inhibitor or taxane in relation to pretherapy AR-V7 status. Results Among the 142 patients in the study (mean [SD] age, 69.5 [9.6] years), 70 were designated as high risk by conventional prognostic factors. In this high-risk group, patients positive for AR-V7 who were treated with taxanes had superior overall survival relative to those treated with ARS inhibitors (median overall survival, 14.3 vs 7.3 months; hazard ratio, 0.62; 95% CI, 0.28-1.39; P = .25). Patients negative for AR-V7 who were treated with ARS inhibitors had superior overall survival relative to those treated with taxanes (median overall survival, 19.8 vs 12.8 months; hazard ratio, 1.67; 95% CI, 1.00-2.81; P = .05). Conclusions and Relevance This study suggests that nuclear-localized AR-V7 protein in circulating tumor cells can identify patients who may live longer with taxane chemotherapy vs ARS inhibitor treatment.
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Affiliation(s)
- Howard I. Scher
- Genitourinary Oncology Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, New York
- Department of Medicine, Weill Cornell Medical College, New York, New York
| | | | - Nicole A. Schreiber
- Genitourinary Oncology Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Anuradha Jayaram
- Centre for Evolution and Cancer, The Institute of Cancer Research, London, United Kingdom
- The Royal Marsden National Health Service Foundation Trust, London, United Kingdom
| | - Eric Winquist
- Department of Oncology, Western University, London, Ontario, Canada
- London Regional Cancer Program, London Health Sciences Centre, London, Ontario, Canada
| | - Brigit McLaughlin
- Genitourinary Oncology Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, New York
| | - David Lu
- Epic Sciences, San Diego, California
| | - Martin Fleisher
- Clinical Chemistry Service, Department of Laboratory Medicine, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Sarah Orr
- Epic Sciences, San Diego, California
| | - Lori Lowes
- Department of Oncology, Western University, London, Ontario, Canada
- London Regional Cancer Program, London Health Sciences Centre, London, Ontario, Canada
| | | | | | | | - Alison L. Allan
- Department of Oncology, Western University, London, Ontario, Canada
- London Regional Cancer Program, London Health Sciences Centre, London, Ontario, Canada
| | - Gerhardt Attard
- Centre for Evolution and Cancer, The Institute of Cancer Research, London, United Kingdom
- The Royal Marsden National Health Service Foundation Trust, London, United Kingdom
| | - Glenn Heller
- Biostatistics Service, Department of Epidemiology and Biostatistics, Memorial Sloan Kettering Cancer Center, New York, New York
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Bernemann C, Steinestel J, Humberg V, Bögemann M, Schrader AJ, Lennerz JK. Performance comparison of two androgen receptor splice variant 7 (AR-V7) detection methods. BJU Int 2018; 122:219-226. [PMID: 29359890 DOI: 10.1111/bju.14146] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
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. We assessed in vitro performance using eight genitourinary cancer cell lines and serial dilutions in three AR-V7-positive prostate cancer cell lines, as well as in 32 blood samples from patients with CRPC. RESULTS Both assays performed identically in the cell lines and serial dilutions showed identical diagnostic thresholds. Performance comparison in 32 clinical patient samples showed perfect concordance between the assays. In particular, both assays determined AR-V7 mRNA-positive CTCs in three patients with unexpected responses to next-generation anti-androgen therapy. Thus, technical differences between the assays can be excluded as the underlying reason for the unexpected responses to next-generation anti-androgen therapy in a subset of AR-V7 patients. CONCLUSIONS Irrespective of the method used, patients with AR-V7 mRNA-positive CRPC should not be systematically precluded from an otherwise safe treatment option.
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Affiliation(s)
| | - Julie Steinestel
- Urology, University of Muenster Medical Center, Muenster, Germany
| | - Verena Humberg
- Urology, University of Muenster Medical Center, Muenster, Germany
| | - Martin Bögemann
- Urology, University of Muenster Medical Center, Muenster, Germany
| | | | - Jochen K Lennerz
- Massachusetts General Hospital/Harvard Medical School, Boston, MA, USA
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10
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Bastos DA, Antonarakis ES. CTC-derived AR-V7 detection as a prognostic and predictive biomarker in advanced prostate cancer. Expert Rev Mol Diagn 2018; 18:155-163. [PMID: 29319382 PMCID: PMC6088794 DOI: 10.1080/14737159.2018.1427068] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
INTRODUCTION 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. Areas covered: In this manuscript, the authors review the available biomarkers in CRPC and discuss emerging data on the value of CTC-derived AR-V7 status to assess prognosis and its potential role to guide treatment selection for patients with advanced prostate cancer. Expert commentary: Current evidence supports AR-V7 status as a prognostic biomarker and also as a potential predictive biomarker for patients with mCRPC. The authors expect that the incorporation of AR-V7 status and other biomarkers (e.g. AR mutations) in the sequential assessment of patients with advanced prostate cancer will lead to a more rational use of available and future therapies, with significant improvements in outcomes for our patients.
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MESH Headings
- Alternative Splicing
- Androgen Antagonists/pharmacology
- Androgen Antagonists/therapeutic use
- Antineoplastic Agents, Hormonal/pharmacology
- Antineoplastic Agents, Hormonal/therapeutic use
- Biomarkers, Tumor
- Humans
- Male
- Mutation
- Neoplasm Staging
- Neoplastic Cells, Circulating/metabolism
- Neoplastic Cells, Circulating/pathology
- Prognosis
- Prostatic Neoplasms/blood
- Prostatic Neoplasms/diagnosis
- Prostatic Neoplasms/drug therapy
- Prostatic Neoplasms/genetics
- Prostatic Neoplasms, Castration-Resistant/blood
- Prostatic Neoplasms, Castration-Resistant/diagnosis
- Prostatic Neoplasms, Castration-Resistant/drug therapy
- Prostatic Neoplasms, Castration-Resistant/genetics
- Receptors, Androgen/genetics
- Signal Transduction/drug effects
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Affiliation(s)
- Diogo A. Bastos
- Department of Oncology, Hospital Sirio-Libanes, Sao Paulo-SP, Brazil
| | - Emmanuel S. Antonarakis
- Departments of Oncology and Urology, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
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11
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Luo J, Luber B, Wang H, Antonarakis ES. Reply to Julie Steinestel, Christof Bernemann, Andres J. Schrader, and Jochen K. Lennerz's Letter to the Editor re: Emmanuel S. Antonarakis, Changxue Lu, Brandon Luber, et al. Clinical Significance of Androgen Receptor Splice Variant-7 mRNA Detection in Circulating Tumor Cells of Men with Metastatic Castration-resistant Prostate Cancer Treated with First- and Second-line Abiraterone and Enzalutamide. J Clin Oncol 2017;35:2149-56. AR-V7 Testing: What's in it for the Patient?: Estimating the Clinical Utility of Blood-based AR-V7 Testing in Prostate Cancer. Eur Urol 2017; 72:e170-e171. [PMID: 28693939 DOI: 10.1016/j.eururo.2017.06.032] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Accepted: 06/21/2017] [Indexed: 12/22/2022]
Affiliation(s)
- Jun Luo
- Department of Urology, The James Buchanan Brady Urological Institute, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
| | - Brandon Luber
- Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Hao Wang
- Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
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12
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Steinestel J, Bernemann C, Schrader AJ, Lennerz JK. Re: Emmanuel S. Antonarakis, Changxue Lu, Brandon Luber, et al. Clinical Significance of Androgen Receptor Splice Variant-7 mRNA Detection in Circulating Tumor Cells of Men with Metastatic Castration-resistant Prostate Cancer Treated with First- and Second-line Abiraterone and Enzalutamide. J Clin Oncol 2017;35:2149-56: AR-V7 Testing: What's in it for the Patient? Eur Urol 2017; 72:e168-e169. [PMID: 28688614 DOI: 10.1016/j.eururo.2017.06.031] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Accepted: 06/21/2017] [Indexed: 11/24/2022]
Affiliation(s)
- Julie Steinestel
- Department of Urology, University Hospital Muenster, Muenster, Germany.
| | | | - Andres J Schrader
- Department of Urology, University Hospital Muenster, Muenster, Germany
| | - Jochen K Lennerz
- Department of Pathology, Center for Integrated Diagnostics, Massachusetts General Hospital/Harvard Medical School, Boston, MA, USA
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Steinestel J, Bernemann C, Schrader AJ, Lennerz JK. Reply from Authors re: Emmanuel S. Antonarakis, Howard I. Scher. Do Patients With AR-V7–Positive Prostate Cancer Benefit from Novel Hormonal Therapies? It All Depends on Definitions. Eur Urol 2017;71:4–6. Eur Urol 2017; 71:6-7. [DOI: 10.1016/j.eururo.2016.08.071] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2016] [Accepted: 08/31/2016] [Indexed: 11/16/2022]
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Scher HI, Graf RP, Schreiber NA, McLaughlin B, Lu D, Louw J, Danila DC, Dugan L, Johnson A, Heller G, Fleisher M, Dittamore R. Nuclear-specific AR-V7 Protein Localization is Necessary to Guide Treatment Selection in Metastatic Castration-resistant Prostate Cancer. Eur Urol 2016; 71:874-882. [PMID: 27979426 DOI: 10.1016/j.eururo.2016.11.024] [Citation(s) in RCA: 144] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2016] [Accepted: 11/16/2016] [Indexed: 12/12/2022]
Abstract
BACKGROUND Circulating tumor cells (CTCs) expressing AR-V7 protein localized to the nucleus (nuclear-specific) identify metastatic castration-resistant prostate cancer (mCRPC) patients with improved overall survival (OS) on taxane therapy relative to the androgen receptor signaling inhibitors (ARSi) abiraterone acetate, enzalutamide, and apalutamide. OBJECTIVE To evaluate if expanding the positivity criteria to include both nuclear and cytoplasmic AR-V7 localization ("nuclear-agnostic") identifies more patients who would benefit from a taxane over an ARSi. DESIGN, SETTING, AND PARTICIPANTS The study used a cross-sectional cohort. Between December 2012 and March 2015, 193 pretherapy blood samples, 191 of which were evaluable, were collected and processed from 161 unique mCRPC patients before starting a new line of systemic therapy for disease progression at the Memorial Sloan Kettering Cancer Center. The association between two AR-V7 scoring criteria, post-therapy prostate-specific antigen (PSA) change (PTPC) and OS following ARSi or taxane treatment, was explored. One criterion required nuclear-specific AR-V7 localization, and the other required an AR-V7 signal but was agnostic to protein localization in CTCs. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSES Correlation of AR-V7 status to PTPC and OS was investigated. Relationships with survival were analyzed using multivariable Cox regression and log-rank analyses. RESULTS AND LIMITATIONS A total of 34 (18%) samples were AR-V7-positive using nuclear-specific criteria, and 56 (29%) were AR-V7-positive using nuclear-agnostic criteria. Following ARSi treatment, none of the 16 nuclear-specific AR-V7-positive samples and six of the 32 (19%) nuclear-agnostic AR-V7-positive samples had ≥50% PTPC at 12 weeks. The strongest baseline factor influencing OS was the interaction between the presence of nuclear-specific AR-V7-positive CTCs and treatment with a taxane (hazard ratio 0.24, 95% confidence interval 0.078-0.79; p=0.019). This interaction was not significant when nuclear-agnostic criteria were used. CONCLUSIONS To reliably inform treatment selection using an AR-V7 protein biomarker in CTCs, nuclear-specific localization is required. PATIENT SUMMARY We analyzed outcomes for patients with metastatic castration-resistant prostate cancer on androgen receptor signaling inhibitors and standard chemotherapy. Patients with circulating tumor cells that had AR-V7 protein in the cellular nuclei were very likely to survive longer on taxane-based chemotherapy, and tests unable to distinguish where the protein is located in the cell are not as predictive of benefit.
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MESH Headings
- Aged
- Aged, 80 and over
- Androgen Antagonists/therapeutic use
- Antineoplastic Agents, Phytogenic/therapeutic use
- Biomarkers, Tumor/blood
- Cell Nucleus/chemistry
- Cell Nucleus/pathology
- Chi-Square Distribution
- Cross-Sectional Studies
- Humans
- Kaplan-Meier Estimate
- Liquid Biopsy
- Male
- Middle Aged
- Multivariate Analysis
- Neoplastic Cells, Circulating/chemistry
- Neoplastic Cells, Circulating/pathology
- Patient Selection
- Predictive Value of Tests
- Prognosis
- Proportional Hazards Models
- Prostatic Neoplasms, Castration-Resistant/blood
- Prostatic Neoplasms, Castration-Resistant/drug therapy
- Prostatic Neoplasms, Castration-Resistant/mortality
- Prostatic Neoplasms, Castration-Resistant/pathology
- Protein Isoforms
- Receptors, Androgen/blood
- Taxoids/therapeutic use
- Time Factors
- Treatment Outcome
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Affiliation(s)
- Howard I Scher
- Genitourinary Oncology Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY, USA; Department of Medicine, Weill Cornell Medical College, New York, NY, USA.
| | | | - Nicole A Schreiber
- Genitourinary Oncology Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Brigit McLaughlin
- Genitourinary Oncology Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - David Lu
- Epic Sciences, La Jolla, CA, USA
| | | | - Daniel C Danila
- Genitourinary Oncology Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY, USA; Department of Medicine, Weill Cornell Medical College, New York, NY, USA
| | | | | | - Glenn Heller
- Biostatistics Service, Department of Epidemiology and Biostatistics, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Martin Fleisher
- Clinical Chemistry Service, Department of Laboratory Medicine, Memorial Sloan Kettering Cancer Center, New York, NY, USA
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