1
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Marklund M, Schultz N, Friedrich S, Berglund E, Tarish F, Tanoglidi A, Liu Y, Bergenstråhle L, Erickson A, Helleday T, Lamb AD, Sonnhammer E, Lundeberg J. Spatio-temporal analysis of prostate tumors in situ suggests pre-existence of treatment-resistant clones. Nat Commun 2022; 13:5475. [PMID: 36115838 PMCID: PMC9482614 DOI: 10.1038/s41467-022-33069-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Accepted: 08/30/2022] [Indexed: 11/25/2022] Open
Abstract
The molecular mechanisms underlying lethal castration-resistant prostate cancer remain poorly understood, with intratumoral heterogeneity a likely contributing factor. To examine the temporal aspects of resistance, we analyze tumor heterogeneity in needle biopsies collected before and after treatment with androgen deprivation therapy. By doing so, we are able to couple clinical responsiveness and morphological information such as Gleason score to transcriptome-wide data. Our data-driven analysis of transcriptomes identifies several distinct intratumoral cell populations, characterized by their unique gene expression profiles. Certain cell populations present before treatment exhibit gene expression profiles that match those of resistant tumor cell clusters, present after treatment. We confirm that these clusters are resistant by the localization of active androgen receptors to the nuclei in cancer cells post-treatment. Our data also demonstrates that most stromal cells adjacent to resistant clusters do not express the androgen receptor, and we identify differentially expressed genes for these cells. Altogether, this study shows the potential to increase the power in predicting resistant tumors.
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Affiliation(s)
- Maja Marklund
- Department of Gene Technology, KTH Royal Institute of Technology, Science for Life Laboratory, Solna, Sweden
| | - Niklas Schultz
- Division of Translational Medicine & Chemical Biology, Karolinska Institute, Science for Life Laboratory, Solna, Sweden
| | - Stefanie Friedrich
- Department of Biochemistry and Biophysics, Stockholm University, Science for Laboratory, Solna, Sweden
| | - Emelie Berglund
- Department of Gene Technology, KTH Royal Institute of Technology, Science for Life Laboratory, Solna, Sweden
| | - Firas Tarish
- Division of Translational Medicine & Chemical Biology, Karolinska Institute, Science for Life Laboratory, Solna, Sweden
| | - Anna Tanoglidi
- Department of Pathology, Evangelismos General Hospital, 45-47 Ipsilantou str, Athens, Greece
| | - Yao Liu
- Division of Translational Medicine & Chemical Biology, Karolinska Institute, Science for Life Laboratory, Solna, Sweden
| | - Ludvig Bergenstråhle
- Department of Gene Technology, KTH Royal Institute of Technology, Science for Life Laboratory, Solna, Sweden
| | - Andrew Erickson
- Nuffield Department of Surgical Sciences, University of Oxford, Oxford, UK
| | - Thomas Helleday
- Division of Translational Medicine & Chemical Biology, Karolinska Institute, Science for Life Laboratory, Solna, Sweden
| | - Alastair D Lamb
- Nuffield Department of Surgical Sciences, University of Oxford, Oxford, UK
| | - Erik Sonnhammer
- Department of Biochemistry and Biophysics, Stockholm University, Science for Laboratory, Solna, Sweden.
| | - Joakim Lundeberg
- Department of Gene Technology, KTH Royal Institute of Technology, Science for Life Laboratory, Solna, Sweden.
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2
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Somasekharan SP, Saxena N, Zhang F, Beraldi E, Huang J, Gentle C, Fazli L, Thi M, Sorensen P, Gleave M. Regulation of AR mRNA translation in response to acute AR pathway inhibition. Nucleic Acids Res 2021; 50:1069-1091. [PMID: 34939643 PMCID: PMC8789049 DOI: 10.1093/nar/gkab1247] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Revised: 11/27/2021] [Accepted: 12/03/2021] [Indexed: 12/20/2022] Open
Abstract
We report a new mechanism of androgen receptor (AR) mRNA regulation and cytoprotection in response to AR pathway inhibition (ARPI) stress in prostate cancer (PCA). AR mRNA translation is coordinately regulated by RNA binding proteins, YTHDF3 and G3BP1. Under ambient conditions m6A-modified AR mRNA is bound by YTHDF3 and translationally stimulated, while m6A-unmodified AR mRNA is bound by G3BP1 and translationally repressed. When AR-regulated PCA cell lines are subjected to ARPI stress, m6A-modified AR mRNA is recruited from actively translating polysomes (PSs) to RNA-protein stress granules (SGs), leading to reduced AR mRNA translation. After ARPI stress, m6A-modified AR mRNA liquid–liquid phase separated with YTHDF3, while m6A-unmodified AR mRNA phase separated with G3BP1. Accordingly, these AR mRNA messages form two distinct YTHDF3-enriched or G3BP1-enriched clusters in SGs. ARPI-induced SG formation is cell-protective, which when blocked by YTHDF3 or G3BP1 silencing increases PCA cell death in response to ARPI stress. Interestingly, AR mRNA silencing also delays ARPI stress-induced SG formation, highlighting its supportive role in triggering this stress response. Our results define a new mechanism for stress adaptive cell survival after ARPI stress involving SG-regulated translation of AR mRNA, mediated by m6A RNA modification and their respective regulatory proteins.
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Affiliation(s)
- Syam Prakash Somasekharan
- Department of Urologic Sciences, University of British Columbia, Vancouver Prostate Centre, Vancouver, Canada
| | - Neetu Saxena
- Department of Urologic Sciences, University of British Columbia, Vancouver Prostate Centre, Vancouver, Canada
| | - Fan Zhang
- Department of Urologic Sciences, University of British Columbia, Vancouver Prostate Centre, Vancouver, Canada
| | - Eliana Beraldi
- Department of Urologic Sciences, University of British Columbia, Vancouver Prostate Centre, Vancouver, Canada
| | - Jia Ni Huang
- Department of Urologic Sciences, University of British Columbia, Vancouver Prostate Centre, Vancouver, Canada
| | - Christina Gentle
- Department of Urologic Sciences, University of British Columbia, Vancouver Prostate Centre, Vancouver, Canada
| | - Ladan Fazli
- Department of Urologic Sciences, University of British Columbia, Vancouver Prostate Centre, Vancouver, Canada
| | - Marisa Thi
- Department of Urologic Sciences, University of British Columbia, Vancouver Prostate Centre, Vancouver, Canada
| | - Poul H Sorensen
- British Columbia Cancer Research Centre, 675 West 10th Avenue, Vancouver, British Columbia, Canada and Department of Pathology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Martin Gleave
- Department of Urologic Sciences, University of British Columbia, Vancouver Prostate Centre, Vancouver, Canada
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3
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Holly JMP, Biernacka K, Perks CM. The role of insulin-like growth factors in the development of prostate cancer. Expert Rev Endocrinol Metab 2020; 15:237-250. [PMID: 32441162 DOI: 10.1080/17446651.2020.1764844] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Accepted: 05/01/2020] [Indexed: 12/20/2022]
Abstract
INTRODUCTION Preclinical, clinical, and population studies have provided robust evidence for an important role for the insulin-like growth factor (IGF) system in the development of prostate cancer. AREAS COVERED An overview of the IGF system is provided. The evidence implicating the IGF system in the development of prostate cancer is summarized. The compelling evidence culminated in a number of clinical trials of agents targeting the system; the reasons for the failure of these trials are discussed. EXPERT OPINION Clinical trials of agents targeting the IGF system in prostate cancer were terminated due to limited objective clinical responses and are unlikely to be resumed unless a convincing predictive biomarker is identified that would enable the selection of likely responders. The aging population and increased screening will lead to greater diagnosis of prostate cancer. Although the vast majority will be indolent disease, the epidemics of obesity and diabetes will increase the proportion that progress to clinical disease. The increased population of worried men will result in more trials aimed to reduce the risk of disease progression; actual clinical endpoints will be challenging and the IGFs remain the best intermediate biomarkers to indicate a response that could alter the course of disease.
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Affiliation(s)
- Jeff M P Holly
- IGFs & Metabolic Endocrinology Group, Faculty of Health Sciences, School of Translational Health Science, University of Bristol, Southmead Hospital , Bristol, UK
| | - Kalina Biernacka
- IGFs & Metabolic Endocrinology Group, Faculty of Health Sciences, School of Translational Health Science, University of Bristol, Southmead Hospital , Bristol, UK
| | - Claire M Perks
- IGFs & Metabolic Endocrinology Group, Faculty of Health Sciences, School of Translational Health Science, University of Bristol, Southmead Hospital , Bristol, UK
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4
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Maimaiti M, Sakamoto S, Yamada Y, Sugiura M, Rii J, Takeuchi N, Imamura Y, Furihata T, Ando K, Higuchi K, Xu M, Sazuka T, Nakamura K, Kaneda A, Kanai Y, Kyprianou N, Ikehara Y, Anzai N, Ichikawa T. Expression of L-type amino acid transporter 1 as a molecular target for prognostic and therapeutic indicators in bladder carcinoma. Sci Rep 2020; 10:1292. [PMID: 31992742 PMCID: PMC6987139 DOI: 10.1038/s41598-020-58136-x] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2019] [Accepted: 01/09/2020] [Indexed: 12/24/2022] Open
Abstract
L-type amino acid transporter 1 (LAT1) plays a role in transporting essential amino acids including leucine, which regulates the mTOR signaling pathway. Here, we studied the expression profile and functional role of LAT1 in bladder cancer. Furthermore, the pharmacological activity of JPH203, a specific inhibitor of LAT1, was studied in bladder cancer. LAT1 expression in bladder cancer cells was higher than that in normal cells. SiLAT1 and JPH203 suppressed cell proliferative and migratory and invasive abilities in bladder cancer cells. JPH203 inhibited leucine uptake by > 90%. RNA-seq analysis identified insulin-like growth factor-binding protein-5 (IGFBP-5) as a downstream target of JPH203. JPH203 inhibited phosphorylation of MAPK / Erk, AKT, p70S6K and 4EBP-1. Multivariate analysis revealed that high LAT1 expression was found as an independent prognostic factor for overall survival (HR3.46 P = 0.0204). Patients with high LAT1 and IGFBP-5 expression had significantly shorter overall survival periods than those with low expression (P = 0.0005). High LAT1 was related to the high Grade, pathological T stage, LDH, and NLR. Collectively, LAT1 significantly contributed to bladder cancer progression. Targeting LAT1 by JPH203 may represent a novel therapeutic option in bladder cancer treatment.
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Affiliation(s)
- Maihulan Maimaiti
- Department of Urology, Chiba University Graduate School of Medicine, Chiba, Japan
| | - Shinichi Sakamoto
- Department of Urology, Chiba University Graduate School of Medicine, Chiba, Japan.
| | - Yasutaka Yamada
- Department of Urology, Chiba University Graduate School of Medicine, Chiba, Japan
| | - Masahiro Sugiura
- Department of Urology, Chiba University Graduate School of Medicine, Chiba, Japan
- Department of Molecular Oncology, Chiba University Graduate School of Medicine, Chiba, Japan
| | - Junryo Rii
- Department of Urology, Chiba University Graduate School of Medicine, Chiba, Japan
| | - Nobuyoshi Takeuchi
- Department of Urology, Chiba University Graduate School of Medicine, Chiba, Japan
- Department of Tumor Pathology, Chiba University Graduate School of Medicine, Chiba, Japan
| | - Yusuke Imamura
- Department of Urology, Chiba University Graduate School of Medicine, Chiba, Japan
| | - Tomomi Furihata
- Department of Pharmacology, Chiba University Graduate School of Medicine, Chiba, Japan
| | - Keisuke Ando
- Department of Urology, Chiba University Graduate School of Medicine, Chiba, Japan
- Department of Pharmacology, Chiba University Graduate School of Medicine, Chiba, Japan
| | - Kosuke Higuchi
- Department of Urology, Chiba University Graduate School of Medicine, Chiba, Japan
- Department of Pharmacology, Chiba University Graduate School of Medicine, Chiba, Japan
| | - Minhui Xu
- Bio-system Pharmacology, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Tomokazu Sazuka
- Department of Urology, Chiba University Graduate School of Medicine, Chiba, Japan
| | - Kazuyoshi Nakamura
- Department of Urology, Chiba University Graduate School of Medicine, Chiba, Japan
| | - Atsushi Kaneda
- Department of Molecular Oncology, Chiba University Graduate School of Medicine, Chiba, Japan
| | - Yoshikatsu Kanai
- Bio-system Pharmacology, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Natasha Kyprianou
- Department of Urology, University of Kentucky College of Medicine, Lexington, KY, USA
| | - Yuzuru Ikehara
- Department of Tumor Pathology, Chiba University Graduate School of Medicine, Chiba, Japan
| | - Naohiko Anzai
- Department of Pharmacology, Chiba University Graduate School of Medicine, Chiba, Japan
| | - Tomohiko Ichikawa
- Department of Urology, Chiba University Graduate School of Medicine, Chiba, Japan
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5
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Duan C, Allard JB. Insulin-Like Growth Factor Binding Protein-5 in Physiology and Disease. Front Endocrinol (Lausanne) 2020; 11:100. [PMID: 32194505 PMCID: PMC7063065 DOI: 10.3389/fendo.2020.00100] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Accepted: 02/17/2020] [Indexed: 12/25/2022] Open
Abstract
Insulin-like growth factor (IGF) signaling is regulated by a conserved family of IGF binding proteins (IGFBPs) in vertebrates. Among the six distinct types of IGFBPs, IGFBP-5 is the most highly conserved across species and has the broadest range of biological activities. IGFBP-5 is expressed in diverse cell types, and its expression level is regulated by a variety of signaling pathways in different contexts. IGFBP-5 can exert a range of biological actions including prolonging the half-life of IGFs in the circulation, inhibition of IGF signaling by competing with the IGF-1 receptor for ligand binding, concentrating IGFs in certain cells and tissues, and potentiation of IGF signaling by delivery of IGFs to the IGF-1 receptor. IGFBP-5 also has IGF-independent activities and is even detected in the nucleus. Its broad biological activities make IGFBP-5 an excellent representative for understanding IGFBP functions. Despite its evolutionary conservation and numerous biological activities, knockout of IGFBP-5 in mice produced only a negligible phenotype. Recent research has begun to explain this paradox by demonstrating cell type-specific and physiological/pathological context-dependent roles for IGFBP-5. In this review, we survey and discuss what is currently known about IGFBP-5 in normal physiology and human disease. Based on recent in vivo genetic evidence, we suggest that IGFBP-5 is a multifunctional protein with the ability to act as a molecular switch to conditionally regulate IGF signaling.
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6
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Slater T, Haywood NJ, Matthews C, Cheema H, Wheatcroft SB. Insulin-like growth factor binding proteins and angiogenesis: from cancer to cardiovascular disease. Cytokine Growth Factor Rev 2019; 46:28-35. [PMID: 30954375 DOI: 10.1016/j.cytogfr.2019.03.005] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Accepted: 03/15/2019] [Indexed: 12/22/2022]
Abstract
Angiogenesis is a tightly regulated activity that is vital during embryonic development and for normal physiological repair processes and reproduction in healthy adults. Pathological angiogenesis is a driving force behind a variety of diseases including cancer and retinopathies, and inhibition of angiogenesis is a therapeutic option that has been the subject of much research, with several inhibitory agents now available for medical therapy. Conversely, therapeutic angiogenesis has been mooted as having significant potential in the treatment of ischemic conditions such as angina pectoris and peripheral arterial disease, but so far there has been less translation from lab to bedside. The insulin-like growth factor binding proteins (IGFBP) are a family of seven proteins essential for the binding and transport of the insulin-like growth factors (IGF). It is being increasingly recognised that IGFBPs have a significant role beyond simply modulating IGF activity, with evidence of both IGF dependent and independent actions through a variety of mechanisms. Moreover, the action of the IGFBPs can be stimulatory or inhibitory depending on the cell type and environment. Specifically the IGFBPs have been heavily implicated in angiogenesis, both pathological and physiological, and they have significant promise as targeted cell therapy agents for both pathological angiogenesis inhibition and therapeutic angiogenesis following ischemic injury. In this short review we will explore the current understanding of the individual impact of each IGFBP on angiogenesis, and the pathways through which these effects occur.
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Affiliation(s)
- Thomas Slater
- Leeds Institute of Cardiovascular & Metabolic Medicine, School of Medicine, University of Leeds, United Kingdom
| | - Natalie J Haywood
- Leeds Institute of Cardiovascular & Metabolic Medicine, School of Medicine, University of Leeds, United Kingdom
| | - Connor Matthews
- Leeds Institute of Cardiovascular & Metabolic Medicine, School of Medicine, University of Leeds, United Kingdom
| | - Harneet Cheema
- Leeds Institute of Cardiovascular & Metabolic Medicine, School of Medicine, University of Leeds, United Kingdom
| | - Stephen B Wheatcroft
- Leeds Institute of Cardiovascular & Metabolic Medicine, School of Medicine, University of Leeds, United Kingdom.
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7
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Hosseini-Beheshti E, Choi W, Weiswald LB, Kharmate G, Ghaffari M, Roshan-Moniri M, Hassona MD, Chan L, Chin MY, Tai IT, Rennie PS, Fazli L, Tomlinson Guns ES. Exosomes confer pro-survival signals to alter the phenotype of prostate cells in their surrounding environment. Oncotarget 2018; 7:14639-58. [PMID: 26840259 PMCID: PMC4924741 DOI: 10.18632/oncotarget.7052] [Citation(s) in RCA: 64] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2015] [Accepted: 12/22/2015] [Indexed: 12/15/2022] Open
Abstract
Prostate cancer (PCa) is the most frequently diagnosed cancer in men. Current research on tumour-related extracellular vesicles (EVs) suggests that exosomes play a significant role in paracrine signaling pathways, thus potentially influencing cancer progression via multiple mechanisms. In fact, during the last decade numerous studies have revealed the role of EVs in the progression of various pathological conditions including cancer. Moreover, differences in the proteomic, lipidomic, and cholesterol content of exosomes derived from PCa cell lines versus benign prostate cell lines confirm that exosomes could be excellent biomarker candidates. As such, as part of an extensive proteomic analysis using LCMS we previously described a potential role of exosomes as biomarkers for PCa. Current evidence suggests that uptake of EV's into the local tumour microenvironment encouraging us to further examine the role of these vesicles in distinct mechanisms involved in the progression of PCa and castration resistant PCa. For the purpose of this study, we hypothesized that exosomes play a pivotal role in cell-cell communication in the local tumour microenvironment, conferring activation of numerous survival mechanisms during PCa progression and development of therapeutic resistance. Our in vitro results demonstrate that PCa derived exosomes significantly reduce apoptosis, increase cancer cell proliferation and induce cell migration in LNCaP and RWPE-1 cells. In conjunction with our in vitro findings, we have also demonstrated that exosomes increased tumor volume and serum PSA levels in vivo when xenograft bearing mice were administered DU145 cell derived exosomes intravenously. This research suggests that, regardless of androgen receptor phenotype, exosomes derived from PCa cells significantly enhance multiple mechanisms that contribute to PCa progression.
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Affiliation(s)
- Elham Hosseini-Beheshti
- Department of Experimental Medicine University of British Columbia, Vancouver, British Columbia, V6H 3Z6, Canada.,The Vancouver Prostate Centre University of British Columbia, Vancouver, British Columbia, V6H 3Z6, Canada
| | - Wendy Choi
- The Vancouver Prostate Centre University of British Columbia, Vancouver, British Columbia, V6H 3Z6, Canada
| | - Louis-Bastien Weiswald
- Division of Gastroenterology, University of British Columbia, Vancouver, British Columbia, V6H 3Z6, Canada
| | - Geetanjali Kharmate
- The Vancouver Prostate Centre University of British Columbia, Vancouver, British Columbia, V6H 3Z6, Canada
| | - Mazyar Ghaffari
- Department of Experimental Medicine University of British Columbia, Vancouver, British Columbia, V6H 3Z6, Canada.,The Vancouver Prostate Centre University of British Columbia, Vancouver, British Columbia, V6H 3Z6, Canada
| | - Mani Roshan-Moniri
- Department of Experimental Medicine University of British Columbia, Vancouver, British Columbia, V6H 3Z6, Canada.,The Vancouver Prostate Centre University of British Columbia, Vancouver, British Columbia, V6H 3Z6, Canada
| | - Mohamed D Hassona
- The Vancouver Prostate Centre University of British Columbia, Vancouver, British Columbia, V6H 3Z6, Canada
| | - Leslie Chan
- The Vancouver Prostate Centre University of British Columbia, Vancouver, British Columbia, V6H 3Z6, Canada
| | - Mei Yieng Chin
- The Vancouver Prostate Centre University of British Columbia, Vancouver, British Columbia, V6H 3Z6, Canada
| | - Isabella T Tai
- Division of Gastroenterology, University of British Columbia, Vancouver, British Columbia, V6H 3Z6, Canada
| | - Paul S Rennie
- Department of Urologic Sciences University of British Columbia, Vancouver, British Columbia, V6H 3Z6, Canada.,The Vancouver Prostate Centre University of British Columbia, Vancouver, British Columbia, V6H 3Z6, Canada
| | - Ladan Fazli
- Department of Urologic Sciences University of British Columbia, Vancouver, British Columbia, V6H 3Z6, Canada.,The Vancouver Prostate Centre University of British Columbia, Vancouver, British Columbia, V6H 3Z6, Canada
| | - Emma S Tomlinson Guns
- Department of Urologic Sciences University of British Columbia, Vancouver, British Columbia, V6H 3Z6, Canada.,The Vancouver Prostate Centre University of British Columbia, Vancouver, British Columbia, V6H 3Z6, Canada
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8
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de Mello Martins AGG, Allegretta G, Unteregger G, Haupenthal J, Eberhard J, Hoffmann M, van der Zee JA, Junker K, Stöckle M, Müller R, Hartmann RW, Ohlmann CH. CYP17A1-independent production of the neurosteroid-derived 5α-pregnan-3β,6α-diol-20-one in androgen-responsive prostate cancer cell lines under serum starvation and inhibition by Abiraterone. J Steroid Biochem Mol Biol 2017; 174:183-191. [PMID: 28890368 DOI: 10.1016/j.jsbmb.2017.09.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/25/2017] [Revised: 09/05/2017] [Accepted: 09/06/2017] [Indexed: 12/31/2022]
Abstract
CYP17A1-independent intratumoral steroid hormone synthesis is regarded as one possible explanation for resistance to treatment with the CYP17-inhibitor Abiraterone (Abi). The aim of our study was therefore to investigate the steroid metabolism of prostate cancer cells under serum starvation and the effects of Abi treatment. We assessed steroid metabolism in a panel of prostate cancer cells under serum starvation by radioactivity detector-coupled HPLC and HPLC-ESI-ToF-mass spectrometry after treatment with pregnenolone, progesterone and allopregnanolone. We further evaluated the effects of Abi on steroid metabolism of testosterone, dihydrotestosterone (DHT) and dehydroepiandrosterone (DHEA) by enzyme immunoassays (EIAs). Androgen-responsive cell lines metabolized pregnenolone primarily to mitogenic steroid 5α-pregnan-3β,6α-diol-20-one under serum starvation. Co-administration of Abi lead to detectable concentrations of the Abi metabolite Δ4-Abi (D4A), known to inhibit enzymes other than CYP17A1 in steroid metabolism. In addition, co-administration of Abi abrogated pregnenolone metabolism and resulted in a CYP17A1-independent significant increase of DHEA (13- to >100-fold) and DHT (2.5-fold) in androgen-responsive cells. Our results demonstrate the CYP17A1-independent formation of 5α-pregnan-3β,6α-diol-20-one by androgen-responsive prostate cancer cells under serum starvation and its inhibition by Abi. Its metabolism from pregnenolone suggests a major steroidogenesis shift in these cells, hinting at a neuroendocrine transdifferentiation phenomenon. The marked increase of DHEA levels by Abi resembles the steroidogenic pathways in nervous tissue, in a manner that precludes CYP17A1 activity. To which extent these processes are responsible or involved in the development of resistance to Abi, needs to be further elucidated.
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Affiliation(s)
- Antonio G Gomes de Mello Martins
- Department of Drug Design and Optimization (DDOP), Helmholtz Institute for Pharmaceutical Research Saarland, Campus E8.1, 66123 Saarbrücken, Germany
| | - Giuseppe Allegretta
- Department of Drug Design and Optimization (DDOP), Helmholtz Institute for Pharmaceutical Research Saarland, Campus E8.1, 66123 Saarbrücken, Germany
| | - Gerhard Unteregger
- Saarland University, Department of Urology and Pediatric Urology, 66424 Homburg/Saar, Germany
| | - Jörg Haupenthal
- Department of Drug Design and Optimization (DDOP), Helmholtz Institute for Pharmaceutical Research Saarland, Campus E8.1, 66123 Saarbrücken, Germany
| | - Jens Eberhard
- Department of Drug Design and Optimization (DDOP), Helmholtz Institute for Pharmaceutical Research Saarland, Campus E8.1, 66123 Saarbrücken, Germany
| | - Michael Hoffmann
- Department of Microbial Natural Products (MINS), Helmholtz Institute for Pharmaceutical Research Saarland, Campus E8.1, 66123 Saarbrücken, Germany
| | - Jill A van der Zee
- Saarland University, Department of Urology and Pediatric Urology, 66424 Homburg/Saar, Germany
| | - Kerstin Junker
- Saarland University, Department of Urology and Pediatric Urology, 66424 Homburg/Saar, Germany
| | - Michael Stöckle
- Saarland University, Department of Urology and Pediatric Urology, 66424 Homburg/Saar, Germany
| | - Rolf Müller
- Department of Microbial Natural Products (MINS), Helmholtz Institute for Pharmaceutical Research Saarland, Campus E8.1, 66123 Saarbrücken, Germany
| | - Rolf W Hartmann
- Department of Drug Design and Optimization (DDOP), Helmholtz Institute for Pharmaceutical Research Saarland, Campus E8.1, 66123 Saarbrücken, Germany; Department of Pharmaceutical and Medicinal Chemistry, Saarland University, 66123 Saarbrücken, Germany.
| | - Carsten-H Ohlmann
- Saarland University, Department of Urology and Pediatric Urology, 66424 Homburg/Saar, Germany.
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9
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Hormaechea-Agulla D, Gahete MD, Jiménez-Vacas JM, Gómez-Gómez E, Ibáñez-Costa A, L-López F, Rivero-Cortés E, Sarmento-Cabral A, Valero-Rosa J, Carrasco-Valiente J, Sánchez-Sánchez R, Ortega-Salas R, Moreno MM, Tsomaia N, Swanson SM, Culler MD, Requena MJ, Castaño JP, Luque RM. The oncogenic role of the In1-ghrelin splicing variant in prostate cancer aggressiveness. Mol Cancer 2017; 16:146. [PMID: 28851363 PMCID: PMC5576296 DOI: 10.1186/s12943-017-0713-9] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Accepted: 08/15/2017] [Indexed: 01/06/2023] Open
Abstract
Background The Ghrelin-system is a complex, pleiotropic family composed of several peptides, including native-ghrelin and its In1-ghrelin splicing variant, and receptors (GHSR 1a/b), which are dysregulated in various endocrine-related tumors, where they associate to pathophysiological features, but the presence, functional role, and mechanisms of actions of In1-ghrelin splicing variant in prostate-cancer (PCa), is completely unexplored. Herein, we aimed to determine the presence of key ghrelin-system components (native-ghrelin, In1-ghrelin, GHSR1a/1b) and their potential pathophysiological role in prostate cancer (PCa). Methods In1-ghrelin and native-ghrelin expression was evaluated by qPCR in prostate tissues from patients with high PCa-risk (n = 52; fresh-tumoral biopsies), and healthy-prostates (n = 12; from cystoprostatectomies) and correlated with clinical parameters using Spearman-test. In addition, In1-ghrelin and native-ghrelin was measured in plasma from an additional cohort of PCa-patients with different risk levels (n = 30) and control-healthy patients (n = 20). In vivo functional (proliferation/migration) and mechanistic (gene expression/signaling-pathways) assays were performed in PCa-cell lines in response to In1-ghrelin and native-ghrelin treatment, overexpression and/or silencing. Finally, tumor progression was monitored in nude-mice injected with PCa-cells overexpressing In1-ghrelin, native-ghrelin and empty vector (control). Results In1-ghrelin, but not native-ghrelin, was overexpressed in high-risk PCa-samples compared to normal-prostate (NP), and this expression correlated with that of PSA. Conversely, GHSR1a/1b expression was virtually absent. Remarkably, plasmatic In1-ghrelin, but not native-ghrelin, levels were also higher in PCa-patients compared to healthy-controls. Furthermore, In1-ghrelin treatment/overexpression, and to a much lesser extent native-ghrelin, increased aggressiveness features (cell-proliferation, migration and PSA secretion) of NP and PCa cells. Consistently, nude-mice injected with PC-3-cells stably-transfected with In1-ghrelin, but not native-ghrelin, presented larger tumors. These effects were likely mediated by ERK1/2-signaling activation and involved altered expression of key oncogenes/tumor suppressor genes. Finally, In1-ghrelin silencing reduced cell-proliferation and PSA secretion from PCa cells. Conclusions Altogether, our results indicate that In1-ghrelin levels (in tissue) and circulating levels (in plasma) are increased in PCa where it can regulate key pathophysiological processes, thus suggesting that In1-ghrelin may represent a novel biomarker and a new therapeutic target in PCa. Electronic supplementary material The online version of this article (doi:10.1186/s12943-017-0713-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Daniel Hormaechea-Agulla
- Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), Córdoba, Spain.,Department of Cell Biology, Physiology and Immunology, University of Córdoba, Córdoba, Spain.,Reina Sofia University Hospital (HURS), Córdoba, Spain.,CIBERobn, Córdoba, Spain.,ceiA3, Córdoba, Spain
| | - Manuel D Gahete
- Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), Córdoba, Spain.,Department of Cell Biology, Physiology and Immunology, University of Córdoba, Córdoba, Spain.,Reina Sofia University Hospital (HURS), Córdoba, Spain.,CIBERobn, Córdoba, Spain.,ceiA3, Córdoba, Spain
| | - Juan M Jiménez-Vacas
- Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), Córdoba, Spain.,Department of Cell Biology, Physiology and Immunology, University of Córdoba, Córdoba, Spain.,Reina Sofia University Hospital (HURS), Córdoba, Spain.,CIBERobn, Córdoba, Spain.,ceiA3, Córdoba, Spain
| | - Enrique Gómez-Gómez
- Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), Córdoba, Spain.,Reina Sofia University Hospital (HURS), Córdoba, Spain.,Urology Service, HURS/IMIBIC, Córdoba, Spain
| | - Alejandro Ibáñez-Costa
- Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), Córdoba, Spain.,Department of Cell Biology, Physiology and Immunology, University of Córdoba, Córdoba, Spain.,Reina Sofia University Hospital (HURS), Córdoba, Spain.,CIBERobn, Córdoba, Spain.,ceiA3, Córdoba, Spain
| | - Fernando L-López
- Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), Córdoba, Spain.,Department of Cell Biology, Physiology and Immunology, University of Córdoba, Córdoba, Spain.,Reina Sofia University Hospital (HURS), Córdoba, Spain.,CIBERobn, Córdoba, Spain.,ceiA3, Córdoba, Spain
| | - Esther Rivero-Cortés
- Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), Córdoba, Spain.,Department of Cell Biology, Physiology and Immunology, University of Córdoba, Córdoba, Spain.,Reina Sofia University Hospital (HURS), Córdoba, Spain.,CIBERobn, Córdoba, Spain.,ceiA3, Córdoba, Spain
| | - André Sarmento-Cabral
- Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), Córdoba, Spain.,Department of Cell Biology, Physiology and Immunology, University of Córdoba, Córdoba, Spain.,Reina Sofia University Hospital (HURS), Córdoba, Spain.,CIBERobn, Córdoba, Spain.,ceiA3, Córdoba, Spain
| | - José Valero-Rosa
- Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), Córdoba, Spain.,Reina Sofia University Hospital (HURS), Córdoba, Spain.,Urology Service, HURS/IMIBIC, Córdoba, Spain
| | - Julia Carrasco-Valiente
- Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), Córdoba, Spain.,Reina Sofia University Hospital (HURS), Córdoba, Spain.,Urology Service, HURS/IMIBIC, Córdoba, Spain
| | - Rafael Sánchez-Sánchez
- Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), Córdoba, Spain.,Reina Sofia University Hospital (HURS), Córdoba, Spain.,Anatomical Pathology Service, HURS/IMIBIC, Córdoba, Spain
| | - Rosa Ortega-Salas
- Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), Córdoba, Spain.,Reina Sofia University Hospital (HURS), Córdoba, Spain.,Anatomical Pathology Service, HURS/IMIBIC, Córdoba, Spain
| | - María M Moreno
- Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), Córdoba, Spain.,Reina Sofia University Hospital (HURS), Córdoba, Spain.,Anatomical Pathology Service, HURS/IMIBIC, Córdoba, Spain
| | | | - Steve M Swanson
- School of Pharmacy, University of Wisconsin-Madison, Madison, WI, USA
| | | | - María J Requena
- Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), Córdoba, Spain.,Reina Sofia University Hospital (HURS), Córdoba, Spain.,Urology Service, HURS/IMIBIC, Córdoba, Spain
| | - Justo P Castaño
- Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), Córdoba, Spain. .,Department of Cell Biology, Physiology and Immunology, University of Córdoba, Córdoba, Spain. .,Reina Sofia University Hospital (HURS), Córdoba, Spain. .,CIBERobn, Córdoba, Spain. .,ceiA3, Córdoba, Spain.
| | - Raúl M Luque
- Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), Córdoba, Spain. .,Department of Cell Biology, Physiology and Immunology, University of Córdoba, Córdoba, Spain. .,Reina Sofia University Hospital (HURS), Córdoba, Spain. .,CIBERobn, Córdoba, Spain. .,ceiA3, Córdoba, Spain.
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10
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Wang Y, Jia Z, Diao S, Lin X, Lian X, Wang L, Dong R, Liu D, Fan Z. IGFBP5 enhances osteogenic differentiation potential of periodontal ligament stem cells and Wharton's jelly umbilical cord stem cells, via the JNK and MEK/Erk signalling pathways. Cell Prolif 2016; 49:618-27. [PMID: 27484838 DOI: 10.1111/cpr.12284] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2016] [Accepted: 07/11/2016] [Indexed: 12/14/2022] Open
Abstract
OBJECTIVES Mesenchymal stem cell (MSC)-mediated tissue regeneration represents a promising strategy for repair of tissue defects, but its molecular mechanisms remain unclear, restricting the use of MSCs. Our previous study indicated that insulin-like growth factor-binding protein 5 (IGFBP5) exerted a valuable effect on osteogenic differentiation of MSCs, but its molecular mechanisms underlying directed differentiation remained unclear. In this study, we have investigated the molecular role of IGFBP5 in regulating this osteogenic differentiation potential. MATERIALS AND METHODS Periodontal ligament stem cells (PDLSCs) were isolated from periodontal ligament tissue. Wharton's jelly of umbilical cord stem cells (WJCMSCs) was obtained commercially. Lentiviral IGFBP5 shRNA was used to silence IGFBP5. Retroviruses expressing wild-type IGFBP5 were used to overexpress IGFBP5 in the WJCMSCs. Recombinant human IGFBP5 protein (rhIGFBP5) was used to treat PDLSCs for 24 h. Western blot analysis was used to detect the MAPK signalling pathway, and alkaline phosphatase (ALP) activity, Alizarin Red staining and quantitative calcium analysis were used to study osteogenic differentiation potentials. RESULTS Overexpression of IGFBP5 or rhIGFBP5 increased expression levels of phosphorylated c-Jun N-terminal kinase (p-JNK), phosphorylated mitogen-activated protein kinase 1 and 2 (p-MEK1/2) and phosphorylated extracellular regulated protein kinases (p-Erk1/2) in both WJCMSCs and PDLSCs. Consistently, silenced IGFBP5 was found to effectively inhibit expression of p-JNK, p-Erk1/2 and p-MEK1/2 in PDLSCs and WJCMSCs. Furthermore, inhibition of JNK by its inhibitor, SP600125, or MEK/Erk signalling by its inhibitor, PD98059, dramatically blocked IGFBP5-enhanced ALP activity and in vitro mineralization in both PDLSCs and WJCMSCs. CONCLUSIONS Our results demonstrated that IGFBP5 promoted osteogenic differentiation potentials of PDLSCs and WJCMSCs via the JNK and MEK/Erk signalling pathways.
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Affiliation(s)
- Yuejun Wang
- Department of Endodontics, Tianjin Medical University School of Stomatology, Tianjin, China.,Laboratory of Molecular Signaling and Stem Cells Therapy, Beijing Key Laboratory of Tooth Regeneration and Function Reconstruction, Capital Medical University School of Stomatology, Beijing, China
| | - Zhi Jia
- Department of Endodontics, Tianjin Medical University School of Stomatology, Tianjin, China
| | - Shu Diao
- Laboratory of Molecular Signaling and Stem Cells Therapy, Beijing Key Laboratory of Tooth Regeneration and Function Reconstruction, Capital Medical University School of Stomatology, Beijing, China
| | - Xiao Lin
- Laboratory of Molecular Signaling and Stem Cells Therapy, Beijing Key Laboratory of Tooth Regeneration and Function Reconstruction, Capital Medical University School of Stomatology, Beijing, China
| | - Xiaomeng Lian
- Department of Stomatology, Beijing Shijitan hospital, Capital Medical University, Beijing, China
| | - Liping Wang
- Laboratory of Molecular Signaling and Stem Cells Therapy, Beijing Key Laboratory of Tooth Regeneration and Function Reconstruction, Capital Medical University School of Stomatology, Beijing, China
| | - Rui Dong
- Laboratory of Molecular Signaling and Stem Cells Therapy, Beijing Key Laboratory of Tooth Regeneration and Function Reconstruction, Capital Medical University School of Stomatology, Beijing, China.
| | - Dayong Liu
- Department of Endodontics, Tianjin Medical University School of Stomatology, Tianjin, China. .,Molecular Laboratory for Gene Therapy and Tooth Regeneration, Beijing Key Laboratory of Tooth Regeneration and Function Reconstruction, Capital Medical University School of Stomatology, Beijing, China.
| | - Zhipeng Fan
- Laboratory of Molecular Signaling and Stem Cells Therapy, Beijing Key Laboratory of Tooth Regeneration and Function Reconstruction, Capital Medical University School of Stomatology, Beijing, China.
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11
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Kashyap MK. Role of insulin-like growth factor-binding proteins in the pathophysiology and tumorigenesis of gastroesophageal cancers. Tumour Biol 2015; 36:8247-57. [PMID: 26369544 DOI: 10.1007/s13277-015-3972-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2015] [Accepted: 08/21/2015] [Indexed: 02/07/2023] Open
Abstract
The insulin family of proteins include insulin-like growth factor binding proteins (IGFBPs) that are classified into two groups based on their differential affinities to IGFs: IGF high-affinity binding proteins (IGFBP1-6) and IGF low-affinity IGFBP-related proteins (IGFBP-rP1-10). IGFBPs interact with many proteins, including their canonical ligands insulin-like growth factor 1 (IGF-I) and IGF-II. Together with insulin-like growth factor 1 (IGF1) receptor (IGF1R), IGF2R, and ligands (IGF1 and IGF2), IGFBPs participate in a complex signaling axis called IGF-IGFR-IGFBP. Numerous studies have demonstrated that the IGF-IGFR-IGFBP axis is relevant in gastrointestinal (GI) and other cancers. The presence of different IGFBPs have been reported in gastrointestinal cancers, including esophageal squamous cell carcinoma (ESCC), esophageal adenocarcinoma (EAD or EAC), and gastric adenocarcinoma (GAD or GAC). A literature-based survey clearly indicates that an urgent need exists for a focused review of the role of IGFBPs in gastrointestinal cancers. The aim of this review is to present the biochemical and molecular characteristics of IGFBPs with an emphasis specifically on the role of these proteins in the pathophysiology and tumorigenesis of gastroesophageal cancers.
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Affiliation(s)
- Manoj K Kashyap
- Moores Cancer Center, University of California San Diego, 3855 Health Science Drive, La Jolla, CA, 92093-0820, USA.
- Department of Biotechnology, Shoolini University of Biotechnology and Management Sciences, Solan, Himachal Pradesh, India.
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12
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Krasnov GS, Dmitriev AA, Sadritdinova AF, Volchenko NN, Slavnova EN, Danilova TV, Snezhkina AV, Melnikova NV, Fedorova MS, Lakunina VA, Belova AA, Nyushko KM, Alekseev BY, Kaprin AD, Kudryavtseva AV. Molecular genetic mechanisms of drug resistance in prostate cancer. Mol Biol 2015. [DOI: 10.1134/s0026893315050118] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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13
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Heidegger I, Massoner P, Sampson N, Klocker H. The insulin-like growth factor (IGF) axis as an anticancer target in prostate cancer. Cancer Lett 2015; 367:113-21. [PMID: 26231734 DOI: 10.1016/j.canlet.2015.07.026] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2015] [Revised: 07/18/2015] [Accepted: 07/21/2015] [Indexed: 12/21/2022]
Abstract
Prostate cancer (PCa) is the most common cancer and the second leading cause of cancer death in males. In recent years, several new targeting agents have been introduced for the treatment of advanced stages of the disease. However, development of resistance limits the efficacy of new drugs and there is a further need to develop additional novel treatment approaches. One of the most investigated targets in cancer research is the insulin-like growth factor (IGF) axis, whose receptors are overexpressed in several cancer entities including PCa. In preclinical studies in PCa, targeting of the IGF axis receptors showed promising anti-tumor effects. Currently available data on clinical studies do not meet the expectations for this new treatment approach. In this review we provide a summary of preclinical and clinical studies on the IGF axis in PCa including treatment with monoclonal antibodies and tyrosine kinase inhibitors. Moreover, we summarize preliminary results from ongoing studies and discuss limitations and side effects of the substances used. We also address the role of the IGF axis in the biomarkers setting including IGF-binding proteins and genetic variants.
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Affiliation(s)
- Isabel Heidegger
- Division of Experimental Urology, Department of Urology, Innsbruck Medical University, Anichstrasse 35, 6020 Innsbruck, Austria
| | - Petra Massoner
- Division of Experimental Urology, Department of Urology, Innsbruck Medical University, Anichstrasse 35, 6020 Innsbruck, Austria
| | - Natalie Sampson
- Division of Experimental Urology, Department of Urology, Innsbruck Medical University, Anichstrasse 35, 6020 Innsbruck, Austria
| | - Helmut Klocker
- Division of Experimental Urology, Department of Urology, Innsbruck Medical University, Anichstrasse 35, 6020 Innsbruck, Austria.
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14
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Tei H, Miyake H, Fujisawa M. Enhanced sensitivity to sorafenib by inhibition of Akt1 expression in human renal cell carcinoma ACHN cells both in vitro and in vivo. Hum Cell 2015; 28:114-21. [PMID: 25862630 DOI: 10.1007/s13577-015-0112-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2014] [Accepted: 02/18/2015] [Indexed: 12/22/2022]
Abstract
To investigate whether antitumor activity of sorafenib, a potential molecular-targeted agent against RCC is enhanced by silencing Akt1 in a human RCC ACHN model. We established ACHN in which the expression vector containing short hairpin RNA targeting Akt1 was introduced (ACHN/sh-Akt1). Changes in several phenotypes of ACHN/sh-Akt1 following treatment with sorafenib were compared with those of ACHN transfected with control vector alone (ACHN/C) both in vitro and in vivo. When cultured in the standard medium, there was no significant difference in the in vitro growth pattern between ACHN/sh-Akt1 and ACHN/C; however, compared with ACHN/C, ACHN/sh-Akt1 showed a significantly higher sensitivity to sorafenib. Furthermore, treatment with Akt1 inhibitor, A-674563 also resulted in the significantly enhanced sensitivity of parental ACHN to sorafenib. Treatment of ACHN/sh-Akt1 with sorafenib, but not that of ACHN/C, induced marked downregulation of antiapoptotic proteins, including Bcl-2, Bcl-xL, and c-Myc. In vivo administration of sorafenib resulted in the significant growth inhibition of ACHN/sh-Akt1 tumor compared with that of ACHN/C tumor, and despite the lack of Ki-67 labeling index between ACHN/sh-Akt1 and ACHN/C tumors, apoptotic index in ACHN/sh-Akt1 tumor in mice treated with sorafenib was significantly greater than that in ACHN/C tumor. These findings suggest that combined treatment with Akt1 inhibitor and sorafenib could be a promising therapeutic approach for patients with advanced RCC.
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Affiliation(s)
- Hiromoto Tei
- Division of Urology, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe, 650-0017, Japan
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15
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Tian D, Kreeger PK. Analysis of the quantitative balance between insulin-like growth factor (IGF)-1 ligand, receptor, and binding protein levels to predict cell sensitivity and therapeutic efficacy. BMC SYSTEMS BIOLOGY 2014; 8:98. [PMID: 25115504 PMCID: PMC4236724 DOI: 10.1186/s12918-014-0098-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/22/2014] [Accepted: 08/05/2014] [Indexed: 01/06/2023]
Abstract
Background The insulin-like growth factor (IGF) system impacts cell proliferation and is highly activated in ovarian cancer. While an attractive therapeutic target, the IGF system is complex with two receptors (IGF1R, IGF2R), two ligands (IGF1, IGF2), and at least six high affinity IGF-binding proteins (IGFBPs) that regulate the bioavailability of IGF ligands. We hypothesized that a quantitative balance between these different network components regulated cell response. Results OVCAR5, an immortalized ovarian cancer cell line, were found to be sensitive to IGF1, with the dose of IGF1 (i.e., the total mass of IGF1 available) a more reliable predictor of cell response than ligand concentration. The applied dose of IGF1 was depleted by both cell-secreted IGFBPs and endocytic trafficking, with IGFBPs sequestering up to 90% of the available ligand. To explore how different variables (i.e., IGF1, IGFBPs, and IGF1R levels) impacted cell response, a mass-action steady-state model was developed. Examination of the model revealed that the level of IGF1-IGF1R complexes per cell was directly proportional to the extent of proliferation induced by IGF1. Model analysis suggested, and experimental results confirmed, that IGFBPs present during IGF1 treatment significantly decreased IGF1-mediated proliferation. We utilized this model to assess the efficacy of IGF1 and IGF1R antibodies against different network compositions and determined that IGF1R antibodies were more globally effective due to the receptor-limited state of the network. Conclusions Changes that affect IGF1R occupancy have predictable effects on IGF1-induced proliferation and our model captured these effects. Analysis of this model suggests that IGF1R antibodies will be more effective than IGF1 antibodies, although the difference was minimal in conditions with low levels of IGF1 and IGFBPs. Examining how different components of the IGF system influence cell response will be critical to improve our understanding of the IGF signaling network in ovarian cancer.
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16
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Up-regulation of eEF1A2 promotes proliferation and inhibits apoptosis in prostate cancer. Biochem Biophys Res Commun 2014; 450:1-6. [PMID: 24853801 DOI: 10.1016/j.bbrc.2014.05.045] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2014] [Accepted: 05/07/2014] [Indexed: 12/21/2022]
Abstract
BACKGROUND eEF1A2 is a protein translation factor involved in protein synthesis, which possesses important function roles in cancer development. This study aims at investigating the expression pattern of eEF1A2 in prostate cancer and its potential role in prostate cancer development. METHODS We examined the expression level of eEF1A2 in 30 pairs of prostate cancer tissues by using RT-PCR and immunohistochemical staining (IHC). Then we applied siRNA specifically targeting eEF1A2 to down-regulate its expression in DU-145 and PC-3 cells. Flow cytometer was used to explore apoptosis and Western-blot was used to detect the pathway proteins of apoptosis. RESULTS Our results showed that the expression level of eEF1A2 in prostate cancer tissues was significantly higher compared to their corresponding normal tissues. Reduction of eEF1A2 expression in DU-145 and PC-3 cells led to a dramatic inhibition of proliferation accompanied with enhanced apoptosis rate. Western blot revealed that apoptosis pathway proteins (caspase3, BAD, BAX, PUMA) were significantly up-regulated after suppression of eEF1A2. More importantly, the levels of eEF1A2 and caspase3 were inversely correlated in prostate cancer tissues. CONCLUSION Our data suggests that eEF1A2 plays an important role in prostate cancer development, especially in inhibiting apoptosis. So eEF1A2 might serve as a potential therapeutic target in prostate cancer.
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17
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Thomas LN, Merrimen J, Bell DG, Rendon R, Goffin V, Too CKL. Carboxypeptidase-D is elevated in prostate cancer and its anti-apoptotic activity is abolished by combined androgen and prolactin receptor targeting. Prostate 2014; 74:732-42. [PMID: 24615730 DOI: 10.1002/pros.22793] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/12/2013] [Accepted: 01/28/2014] [Indexed: 11/08/2022]
Abstract
BACKGROUND Carboxypeptidase-D (CPD) cleaves C-terminal arginine for nitric oxide (NO) production. CPD and NO levels are upregulated by testosterone (T) and prolactin (PRL) to promote survival of prostate cancer (pCa) cells. This study evaluated CPD immunostaining and T/PRL regulation of CPD and NO levels in benign and malignant prostate tissues/cells to determine the role of CPD in pCa. METHODS Immunohistochemistry (IHC) and tissue microarrays (TMA) were used to determine CPD immunostaining in prostate specimens. QPCR and immunoblotting were used to quantify CPD mRNA/protein expression in prostate cells. NO production was measured using 4,5-diaminofluorescein diacetate assay. RESULTS CPD staining increased from 8.9 ± 3.8% (Mean ± SEM, n = 15) of benign epithelial cell area to 30.9 ± 2.9% (n = 30) of tumor cell area in one set of TMAs (P = 0.0008) and from 5.9 ± 0.9% (n = 45) of benign epithelial cell area to 18.8 ± 1.9% (n = 55) of tumor area in another (P < 0.0001). IHC of prostate tissues (≥50 mm(2)) confirmed increased CPD staining, from 13.1 ± 2.9% in benign (n = 16) to 29.5 ± 4.4% in pCa (n = 31, P = 0.0095). T and/or PRL increased CPD expression in several pCa but not benign cell lines. T and PRL acted synergistically to increase NO production, which was abolished only when receptor antagonists flutamide and Δ1-9-G129R-hPRL were used together. CONCLUSIONS CPD immunostaining and T/PRL-stimulated CPD expression were higher in pCa than benign tissues/cells. Elevated CPD increased NO production, which was abolished when both AR and PRLR were inhibited. Our study implicates a critical role for the T/PRL-stimulated CPD-Arg-NO pathway in pCa progression, and suggests that AR+PRLR inhibition is a more effective treatment for pCa.
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Affiliation(s)
- Lynn N Thomas
- Departments of Biochemistry & Molecular Biology, Faculty of Medicine, Dalhousie University, Halifax, NS, Canada
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18
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Matsumoto H, Yamamoto Y, Shiota M, Kuruma H, Beraldi E, Matsuyama H, Zoubeidi A, Gleave M. Cotargeting Androgen Receptor and Clusterin Delays Castrate-Resistant Prostate Cancer Progression by Inhibiting Adaptive Stress Response and AR Stability. Cancer Res 2013; 73:5206-17. [PMID: 23786771 DOI: 10.1158/0008-5472.can-13-0359] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Although androgen receptor (AR) pathway inhibitors prolong survival in castrate-resistant prostate cancer (CRPC), resistance rapidly develops and is often associated with increased stress-activated molecular chaperones like clusterin (CLU) and continued AR signaling. Because adaptive pathways activated by treatment facilitate development of acquired resistance, cotargeting the stress response, activated by AR inhibition and mediated through CLU, may create conditional lethality and improve outcomes. Here, we report that CLU is induced by AR antagonism and silencing using MDV3100 and antisense, respectively, to become highly expressed in castrate- and MDV3100-resistant tumors and cell lines. CLU, as well as AKT and mitogen-activated protein kinase (MAPK) signalosomes, increase in response to MDV3100-induced stress. Mechanistically, this stress response is coordinated by a feed-forward loop involving p90rsk (RPS6KA)-mediated phosphoactivation of YB-1 with subsequent induction of CLU. CLU inhibition repressed MDV3100-induced activation of AKT and MAPK pathways. In addition, when combined with MDV3100, CLU knockdown accelerated AR degradation and repressed AR transcriptional activity through mechanisms involving decreased YB-1-regulated expression of the AR cochaperone, FKBP52. Cotargeting the AR (with MDV3100) and CLU (with OGX-011) synergistically enhanced apoptotic rates over that seen with MDV3100 or OGX-011 monotherapy and delayed CRPC LNCaP tumor and prostate-specific antigen (PSA) progression in vivo. These data indicate that cotargeting adaptive stress pathways activated by AR pathway inhibitors, and mediated through CLU, creates conditional lethality and provides mechanistic and preclinical proof-of-principle to guide biologically rational combinatorial clinical trial design.
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Affiliation(s)
- Hiroaki Matsumoto
- Authors' Affiliations: The Vancouver Prostate Centre and Department of Urologic Sciences, University of British Columbia, Vancouver, British Columbia, Canada; and Department of Urology, Graduate School of Medicine, Yamaguchi University, Ube, Japan
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19
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Autophagy in prostate cancer and androgen suppression therapy. Int J Mol Sci 2013; 14:12090-106. [PMID: 23743823 PMCID: PMC3709775 DOI: 10.3390/ijms140612090] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2013] [Revised: 05/27/2013] [Accepted: 05/31/2013] [Indexed: 12/19/2022] Open
Abstract
The role of autophagy is known to be highly complex and context-dependent, leading to both cancer suppression and progression in several tumors including melanoma, breast and prostate cancer. In the present review, recent advances in an understanding of the involvement of autophagy in prostate cancer treatment are described. The regulatory effects of androgens on prostate cancer cell autophagy are particularly discussed in order to highlight the effects of autophagy modulation during androgen deprivation. A critical evaluation of the studies examined in the present review suggests the attractive possibility of autophagy inhibition combined with hormonal therapy as a promising approach for prostate cancer treatment.
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20
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Varkaris A, Gaur S, Parikh NU, Song JH, Dayyani F, Jin JK, Logothetis CJ, Gallick GE. Ligand-independent activation of MET through IGF-1/IGF-1R signaling. Int J Cancer 2013; 133:1536-46. [PMID: 23526299 DOI: 10.1002/ijc.28169] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2012] [Accepted: 03/06/2013] [Indexed: 01/07/2023]
Abstract
The receptor tyrosine kinase, MET, has been implicated in tumorigenesis and metastasis of many solid tumors, by multiple mechanisms, including cross talk with epidermal growth factor receptor. In this study, we examined the role of insulin-like growth factor receptor-1 (IGF-1R) signaling in MET activation, focusing on prostate cancer cells. Stimulation of the prostate cancer cell line PC3 with IGF-1 induces a delayed phosphorylation of MET at multiple sites (indicative of full activation), reaching a maximum 18 hr after IGF-1 addition. MET activation does not require the sole MET ligand hepatocyte growth factor (HGF), but does require transcription to occur. Furthermore, direct injection of IGF-1 is sufficient to induce MET activation in vivo, in a PC3 xenograft model. Pharmacologic or genetic inhibition of the tyrosine kinase, Src, abolishes MET phosphorylation, and expression of activated Src is sufficient to induce Met phosphorylation in the absence of IGF-1 stimulation. Activated MET is essential for IGF-1-mediated increased migration of PC3 cells, demonstrating an important biologic effect of IGF-1-mediated MET activation. Finally, we demonstrate that IGF-1-induced delayed MET activation occurs in multiple cell lines which express both the receptors, suggesting that IGF-1R-mediated MET activation may contribute to tumorigenic properties of multiple cancer types when both growth factor receptors are expressed. The results further suggest that MET may be activated by multiple receptor tyrosine kinase receptors, and dual targeting of these receptors may be important therapeutically.
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Affiliation(s)
- Andreas Varkaris
- Department of Genitourinary Medical Oncology, David H. Koch Center for Applied Research of Genitourinary Cancers, The University of Texas M.D. Anderson Cancer Center, 1515 Holcombe Blvd., Houston, TX 77030, USA
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21
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Low CG, Luk ISU, Lin D, Fazli L, Yang K, Xu Y, Gleave M, Gout PW, Wang Y. BIRC6 protein, an inhibitor of apoptosis: role in survival of human prostate cancer cells. PLoS One 2013; 8:e55837. [PMID: 23409057 PMCID: PMC3568134 DOI: 10.1371/journal.pone.0055837] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2012] [Accepted: 01/02/2013] [Indexed: 02/03/2023] Open
Abstract
BACKGROUND BIRC6 is a member of the Inhibitors of Apoptosis Protein (IAP) family which is thought to protect a variety of cancer cells from apoptosis. The main objective of the present study was to investigate whether BIRC6 plays a role in prostate cancer and could be useful as a novel therapeutic target. METHODS BIRC6 expression in cell lines was assessed using Western blot analysis and in clinical samples using immunohistochemistry of tissue microarrays. The biological significance of BIRC6 was determined by siRNA-induced reduction of BIRC6 expression in LNCaP cells followed by functional assays. RESULTS Elevated BIRC6 protein expression was found in prostate cancer cell lines and clinical specimens as distinct from their benign counterparts. Increased BIRC6 expression was associated with Gleason 6-8 cancers and castration resistance. Reduction of BIRC6 expression in LNCaP cells led to a marked reduction in cell proliferation which was associated with an increase in apoptosis and a decrease in autophagosome formation. Doxorubicin-induced apoptosis was found to be coupled to a reduction in BIRC6 protein expression. CONCLUSION The data suggest a role for BIRC6 in prostate cancer progression and treatment resistance, and indicate for the first time that the BIRC6 gene and its product are potentially valuable targets for treatment of prostate cancers.
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Affiliation(s)
- Christopher G. Low
- The Vancouver Prostate Centre, Vancouver General Hospital and Department of Urologic Sciences, the University of British Columbia, Vancouver, British Columbia, Canada
- Department of Experimental Therapeutics, BC Cancer Agency, Vancouver, British Columbia, Canada
| | - Iris S. U. Luk
- The Vancouver Prostate Centre, Vancouver General Hospital and Department of Urologic Sciences, the University of British Columbia, Vancouver, British Columbia, Canada
- Department of Experimental Therapeutics, BC Cancer Agency, Vancouver, British Columbia, Canada
| | - Dong Lin
- The Vancouver Prostate Centre, Vancouver General Hospital and Department of Urologic Sciences, the University of British Columbia, Vancouver, British Columbia, Canada
- Department of Experimental Therapeutics, BC Cancer Agency, Vancouver, British Columbia, Canada
| | - Ladan Fazli
- The Vancouver Prostate Centre, Vancouver General Hospital and Department of Urologic Sciences, the University of British Columbia, Vancouver, British Columbia, Canada
| | - Kuo Yang
- The Vancouver Prostate Centre, Vancouver General Hospital and Department of Urologic Sciences, the University of British Columbia, Vancouver, British Columbia, Canada
- Department of Urology, The Second Hospital of Tianjin Medical University, Tianjin Institute of Urology, Tianjin, China
| | - Yong Xu
- Department of Urology, The Second Hospital of Tianjin Medical University, Tianjin Institute of Urology, Tianjin, China
| | - Martin Gleave
- The Vancouver Prostate Centre, Vancouver General Hospital and Department of Urologic Sciences, the University of British Columbia, Vancouver, British Columbia, Canada
| | - Peter W. Gout
- Department of Experimental Therapeutics, BC Cancer Agency, Vancouver, British Columbia, Canada
| | - Yuzhuo Wang
- The Vancouver Prostate Centre, Vancouver General Hospital and Department of Urologic Sciences, the University of British Columbia, Vancouver, British Columbia, Canada
- Department of Experimental Therapeutics, BC Cancer Agency, Vancouver, British Columbia, Canada
- * E-mail:
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Combined Inhibition of IGF-1R/IR and Src family kinases enhances antitumor effects in prostate cancer by decreasing activated survival pathways. PLoS One 2012; 7:e51189. [PMID: 23300537 PMCID: PMC3530555 DOI: 10.1371/journal.pone.0051189] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2012] [Accepted: 10/30/2012] [Indexed: 11/19/2022] Open
Abstract
Background Treatment of metastatic prostate cancer (PCa) with single agents has shown only modest efficacy. We hypothesized dual inhibition of different pathways in PCa results in improved tumor inhibition. The Src family kinases (SFK) and insulin-like growth factor-1 (IGF-1) signaling axes are aberrantly activated in both primary PCa and bone metastases and regulate distinct and overlapping functions in PCa progression. We examined the antitumor effects of combined inhibition of these pathways. Materials and Methods Src andIGF-1 receptor (IGF-1R) inhibition was achieved in vitro by short hairpin (sh)RNA and in vitro and in vivo by small molecule inhibitors (dasatinib and BMS-754807, against SFK and IGF-1R/Insulin Receptor(IR), respectively). Results In vitro, inhibition of IGF-1 signaling affected cell survival and proliferation. SFK blockade alone had modest effects on proliferation, but significantly enhanced the IGF-1R blockade. These findings correlated with a robust inhibition of IGF-1-induced Akt1 phophorylation by dasatinib, whereas Akt2 phosphorylation was SFK independent and only inhibited by BMS-754807. Thus, complete inhibition of both Akt genes, not seen by either drug alone, is likely a major mechanism for the decreased survival of PCa cells. Furthermore, dasatinib and BMS-754807 inhibited in vivo growth of the primary human xenograft MDA PCa 133, with corresponding inhibition of Akt in tumors. Also, both orthotopic and intratibial tumor growth of PC-3 cells were more potently inhibited by dual SFK and IGF-1R/IR blockade compared to either pathway alone, with a corresponding decrease in bone turnover markers. Conclusions Dual IGF-1R/IR and SFK inhibition may be a rational therapeutic approach in PCa by blocking both independent and complementary processes critical to tumor growth.
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Abstract
PURPOSE OF REVIEW Recent advances in our understanding of the androgen axis signaling pathway have led to the development of therapeutic strategies to overcome the state of 'castration resistance' in prostate cancer. In this review, we examine the mechanisms of castration resistance, as well as recently reported and ongoing clinical studies, which will further identify therapeutic opportunities for novel therapeutics targeting the androgen-signaling axis in advanced prostate cancer. RECENT FINDINGS As evidenced by recently reported positive phase III clinical trials, secondary hormonal agents such as abiraterone and MDV3100 may still be very effective in the treatment of castration-resistant prostate cancer, even after the use of docetaxel chemotherapy. SUMMARY Novel agents targeting this pathway have demonstrated a proof of principle that overcoming castration resistance is possible, leading to significant changes in the landscape of treatment in this disease. The optimal combination, sequence, and pattern of use in these novel therapies will be the focus of clinical research in the near future.
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Kumano M, Furukawa J, Shiota M, Zardan A, Zhang F, Beraldi E, Wiedmann RM, Fazli L, Zoubeidi A, Gleave ME. Cotargeting stress-activated Hsp27 and autophagy as a combinatorial strategy to amplify endoplasmic reticular stress in prostate cancer. Mol Cancer Ther 2012; 11:1661-71. [PMID: 22675041 DOI: 10.1158/1535-7163.mct-12-0072] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Hsp27 is a stress-activated multifunctional chaperone that inhibits treatment-induced apoptosis and causes treatment resistance in prostate and other cancers. We previously showed that targeted suppression of Hsp27 sensitizes cancer cells to hormone and chemotherapy. However, mechanisms by which Hsp27 confers cell treatment resistance are incompletely defined. Here, we report that Hsp27 protects human prostate cancer cells against proteotoxic stress induced by proteasome inhibition, and that Hsp27 silencing using siRNA or antisense (OGX-427) induced both apoptosis and autophagy through mechanisms involving reduced proteasome activity and induction of endoplasmic reticulum (ER) stress. We found that autophagy activation protected against ER stress-induced cell death, whereas inhibition of autophagy activation following Hsp27 silencing using either pharmacologic inhibitors or atg3 silencing enhanced cell death. Importantly, cotargeting Hsp27 and autophagy by combining OGX-427 with the autophagy inhibitor, chloroquine, significantly delayed PC-3 prostate tumor growth in vivo. These findings identify autophagy as a cytoprotective, stress-induced adaptive pathway, activated following disruption of protein homeostasis and ER stress induced by Hsp27 silencing. Combinatorial cotargeting cytoprotective Hsp27 and autophagy illustrates potential benefits of blocking activation of adaptive pathways to improve treatment outcomes in cancer.
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Affiliation(s)
- Masafumi Kumano
- The Vancouver Prostate Centre and Department of Urological Sciences, University of British Columbia, Vancouver, British Columbia, Canada
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25
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Chi KN, Gleave ME, Fazli L, Goldenberg SL, So A, Kollmannsberger C, Murray N, Tinker A, Pollak M. A Phase II Pharmacodynamic Study of Preoperative Figitumumab in Patients with Localized Prostate Cancer. Clin Cancer Res 2012; 18:3407-13. [DOI: 10.1158/1078-0432.ccr-12-0482] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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26
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Güllü G, Karabulut S, Akkiprik M. Functional roles and clinical values of insulin-like growth factor-binding protein-5 in different types of cancers. CHINESE JOURNAL OF CANCER 2012; 31:266-80. [PMID: 22313597 PMCID: PMC3777492 DOI: 10.5732/cjc.011.10405] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Insulin-like growth factor-binding proteins (IGFBPs) are critical regulators of the mitogenic activity of insulin-like growth factors (IGFs). IGFBP5, one of these IGFBPs, has special structural features, including a nuclear transport domain, heparin-binding motif, and IGF/extracellular matrix/acid-labile subunit-binding sites. Furthermore, IGFBP5 has several functional effects on carcinogenesis and even normal cell processes, such as cell growth, death, motility, and tissue remodeling. These biological effects are sometimes related with IGF (IGF-dependent effects) and sometimes not (IGF-independent effects). The functional role of IGFBP5 is most likely determined in a cell-type and tissue-type specific manner but also depends on cell context, especially in terms of the diversity of interacting proteins and the potential for nuclear localization. Clinical findings show that IGFBP5 has the potential to be a useful clinical biomarker for predicting response to therapy and clinical outcome of cancer patients. In this review, we summarize the functional diversity and clinical importance of IGFBP5 in different types of cancers.
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Affiliation(s)
- Gökçe Güllü
- Department of Medical Biology, School of Medicine, DMarmara University, Istanbul 34468, Turkey
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Gallick GE, Corn PG, Zurita AJ, Lin SH. Small-molecule protein tyrosine kinase inhibitors for the treatment of metastatic prostate cancer. Future Med Chem 2012; 4:107-19. [PMID: 22168167 PMCID: PMC3285098 DOI: 10.4155/fmc.11.161] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The microenvironment is critical to the growth of prostate cancer (PCa) in the bone. Thus, for clinical efficacy, therapies must target tumor-microenvironment interactions. Several protein tyrosine kinases have been implicated in the development and growth of PCa bone metastasis. In this review, specific protein tyrosine kinases that regulate these complex interactions, including PDGFR, the EGFR family, c-Src, VEGFR, IGF-1R, FGFR and c-Met will be discussed, with an emphasis on why these kinases are promising therapeutic targets for metastatic PCa treatment. For each of these kinases, small-molecule inhibitors have reached clinical trials. Current results of these trials and future prospects for the use of tyrosine kinase inhibitors for the treatment of PCa bone metastases are also discussed.
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Affiliation(s)
- Gary E Gallick
- Department of Genitourinary Medical Oncology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, TX 77030, USA
| | - Paul G Corn
- Department of Genitourinary Medical Oncology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, TX 77030, USA
| | - Amado J Zurita
- Department of Genitourinary Medical Oncology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, TX 77030, USA
| | - Sue-Hwa Lin
- Department of Genitourinary Medical Oncology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, TX 77030, USA
- Department of Molecular Pathology, Unit 89, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, TX 77030, USA
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Clusterin Is a Critical Downstream Mediator of Stress-Induced YB-1 Transactivation in Prostate Cancer. Mol Cancer Res 2011; 9:1755-66. [DOI: 10.1158/1541-7786.mcr-11-0379] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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29
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Lamoureux F, Thomas C, Yin MJ, Kuruma H, Beraldi E, Fazli L, Zoubeidi A, Gleave ME. Clusterin inhibition using OGX-011 synergistically enhances Hsp90 inhibitor activity by suppressing the heat shock response in castrate-resistant prostate cancer. Cancer Res 2011; 71:5838-49. [PMID: 21737488 DOI: 10.1158/0008-5472.can-11-0994] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Small-molecule inhibitors of Hsp90 show promise in the treatment of castrate-resistant prostate cancer (CRPC); however, these inhibitors trigger a heat shock response that attenuates drug effectiveness. Attenuation is associated with increased expression of Hsp90, Hsp70, Hsp27, and clusterin (CLU) that mediate tumor cell survival and treatment resistance. We hypothesized that preventing CLU induction in this response would enhance Hsp90 inhibitor-induced CRPC cell death in vitro and in vivo. To test this hypothesis, we treated CRPC with the Hsp90 inhibitor PF-04929113 or 17-AAG in the absence or presence of OGX-011, an antisense drug that targets CLU. Treatment with either Hsp90 inhibitor alone increased nuclear translocation and transcriptional activity of the heat shock factor HSF-1, which stimulated dose- and time-dependent increases in HSP expression, especially CLU expression. Treatment-induced increases in CLU were blocked by OGX-011, which synergistically enhanced the activity of Hsp90 inhibition on CRPC cell growth and apoptosis. Accompanying these effects was a decrease in HSF-1 transcriptional activity as well as expression of HSPs, Akt, prostate-specific antigen, and androgen receptor. In vivo evaluation of the Hsp90 inhibitors with OGX-011 in xenograft models of human CRPC showed that OGX-011 markedly potentiated antitumor efficacy, leading to an 80% inhibition of tumor growth with prolonged survival compared with Hsp90 inhibitor monotherapy. Together, our findings indicate that Hsp90 inhibitor-induced activation of the heat shock response and CLU is attenuated by OGX-011, with synergistic effects on delaying CRPC progression.
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Affiliation(s)
- Francois Lamoureux
- The Vancouver Prostate Centre, University of British Columbia, Vancouver, British Columbia, Canada
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30
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Terakawa T, Miyake H, Kumano M, Fujisawa M. Growth inhibition and enhanced chemosensitivity induced by down-regulation of Aurora-A in human renal cell carcinoma Caki-2 cells using short hairpin RNA. Oncol Lett 2011; 2:713-717. [PMID: 22848254 DOI: 10.3892/ol.2011.295] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2010] [Accepted: 04/08/2011] [Indexed: 11/06/2022] Open
Abstract
The objective of this study was to investigate the inhibitory effects of Aurora-A expression on the growth and chemosensitivity of Caki-2 cells in human renal cell carcinoma (RCC). Caki-2 cells were established, in which an expression vector containing short hairpin RNA (shRNA) targeting Aurora-A was introduced (Caki-2/sh-A). The growth and sensitivity of chemotherapeutic agents in Caki-2/sh-A cells were compared to those in Caki-2 cells transfected with control vector alone (Caki-2/C). The expression levels of both Aurora-A mRNA and protein in Caki-2/sh-A cells were less than 10% of those in Caki-2/C cells. The in vitro growth of Caki-2/sh-A cells was significantly inferior to that of Caki-2/C cells, and the proportion of Caki-2/sh-A cells in the G2-M phase was significantly greater compared to that of Caki-2/C cells. In addition, the expression level of Bax in Caki-2/sh-A cells was significantly higher as compared to that in Caki-2/C cells, while phosphorylated Akt in Caki-2/sh-A cells was markedly down-regulated compared to that in Caki-2/C cells. Among several chemotherapeutic agents examined, the most significant difference between Caki-2/sh-A and Caki-2/C cells was observed in the sensitivity to docetaxel. Thus, the IC(50) value of docetaxel in Caki-2/sh-A cells was decreased by approximately 90% compared to that in Caki-2/C cells. Treatment of Caki-2/sh-A cells, but not Caki-2/C ones, with 5 nM docetaxel resulted in the induction of apoptotic cell death accompanying the induction of p53. The findings suggest that the suppression of Aurora-A expression using shRNA is a useful therapeutic strategy against RCC through growth inhibition as well as enhanced chemosensitivity.
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Affiliation(s)
- Tomoaki Terakawa
- Division of Urology, Kobe University Graduate School of Medicine, Kobe 650-0017, Japan
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31
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Jeter CR, Liu B, Liu X, Chen X, Liu C, Calhoun-Davis T, Repass J, Zaehres H, Shen JJ, Tang DG. NANOG promotes cancer stem cell characteristics and prostate cancer resistance to androgen deprivation. Oncogene 2011; 30:3833-45. [PMID: 21499299 PMCID: PMC3140601 DOI: 10.1038/onc.2011.114] [Citation(s) in RCA: 280] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Cancer cell molecular mimicry of stem cells (SC) imbues neoplastic cells with enhanced proliferative and renewal capacities. In support, numerous mediators of SC self-renewal have been evinced to exhibit oncogenic potential. We have recently reported that shRNA-mediated knockdown of the embryonic stem cell (ESC) self-renewal gene NANOG significantly reduced the clonogenic and tumorigenic capabilities of various cancer cells. In this study, we sought to test the potential pro-tumorigenic functions of NANOG, particularly, in prostate cancer (PCa). Using quantitative RT-PCR, we first confirmed that PCa cells expressed NANOG mRNA primarily from the NANOGP8 locus on chromosome 15q14. We then constructed a lentiviral promoter reporter in which the -3.8 kb NANOGP8 genomic fragment was used to drive the expression of green fluorescence protein (GFP). We observed that NANOGP8-GFP+ PCa cells exhibited cancer stem cell (CSC) characteristics such as enhanced clonal growth and tumor regenerative capacity. To further investigate the functions and mechanisms of NANOG in tumorigenesis, we established tetracycline-inducible NANOG overexpressing cancer cell lines, including both prostate (Du145 and LNCaP) and breast (MCF-7) cancer cells. NANOG induction promoted drug-resistance in MCF-7 cells, tumor regeneration in Du145 cells, and, most importantly, castration-resistant tumor development in LNCaP cells. These pro-tumorigenic effects of NANOG were associated with key molecular changes, including an upregulation of molecules such as CXCR4, IGFBP5, CD133 and ALDH1. The present gain-of-function studies, coupled with our recent loss-of-function work, establish the integral role for NANOG in neoplastic processes and shed light on its mechanisms of action.
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Affiliation(s)
- C R Jeter
- Department of Molecular Carcinogenesis, University of Texas MD Anderson Cancer Center, Science Park-Research Division, Smithville, USA.
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Thomas C, Zoubeidi A, Kuruma H, Fazli L, Lamoureux F, Beraldi E, Monia BP, MacLeod AR, Thüroff JW, Gleave ME. Transcription factor Stat5 knockdown enhances androgen receptor degradation and delays castration-resistant prostate cancer progression in vivo. Mol Cancer Ther 2011; 10:347-59. [PMID: 21216933 DOI: 10.1158/1535-7163.mct-10-0850] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Signal transducer and activator of transcription 5 (Stat5) plays an important role in the transition of prostate cancer (PCa) to its castrate-resistant state. Pharmacologic targeting of Stat5 is a rational approach to delay castrate-resistant progression, in part, because Stat5 cooperates with the androgen receptor (AR) to promote PCa progression. Immunostaining of tissue microarrays was used to correlate Stat5 expression with Gleason grade and to characterize changes in treatment-naive and androgen-deprived human PCa. Potency of a Stat5 antisense oligonucleotide (ASO) on Stat5 knockdown, cell growth, and apoptosis was assessed in LNCaP, C4-2, and DU145 cells. Effects of Stat5 knockdown on AR activity and stability was assessed using a PSA transactivation-luciferase assay and cyclohexamide plus MG132 treatment, respectively. LNCaP tumor-bearing mice were castrated and randomly assigned to treatment with Stat5-ASO or controls. Here, we show that the frequency of Stat5 expression is significantly increased in high Gleason grade as well as in hormone-treated PCa. Also, specific knockdown of Stat5 with ASO abrogates androgen-induced AR nuclear translocation and PSA transactivation despite R1881 stimulation. Moreover, Stat5 knockdown destabilizes AR, which leads to AR degradation via the proteasome. Shown for the first time as a preclinical proof-of-principle, Stat5 knockdown with Stat5-ASO significantly delays CRPC tumor progression in vivo. Thereby, we are able to recapitulate our in vitro results by reducing serum PSA and expression levels of target proteins in the xenograft tumors.
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Affiliation(s)
- Christian Thomas
- The Vancouver Prostate Centre, 2660 Oak Street, Vancouver, British Columbia, Canada
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Farooqi AA, Mansoor Q, Ismail M, Bhatti S. Therapeutic Effect of Epigallocatechin-3-gallate (EGCG) and Silibinin on ATM Dynamics in Prostate Cancer Cell Line LNCaP. World J Oncol 2011; 1:242-246. [PMID: 29147215 PMCID: PMC5649750 DOI: 10.4021/wjon248w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/19/2010] [Indexed: 12/03/2022] Open
Abstract
Background Epigallocatechin-3-gallate (EGCG) is a major ingredient of green tea (GT) and silibinin (SB), the active component of Silymarin presumably hold a potential to prevent pathogenomics. Prostate cancer exacerbation is triggered by fusion transcripts formed because of genomic instability induced by juxtapositioning of two genes. This chimeric transcript is implicated in androgen dependent and independent prostate cancer. Tremendous work is done on the characterization of the mediators involved in the disease refractoriness, yet no study has addressed clinical management of these prostate fusion transcripts impressively. Methods An abolished ATM dynamics challenges integrity of DNA. In agreement with this assumption, ATM and DNA-PK were impaired in LNCaP cell line to confirm a tight interaction of these mediators with the expression profile of TMPRSS2-ERG. Abolished ATM enhanced the expression of the fusion transcript. Similarly blunting of DNA-PK downregulated the expression of the fusion transcript giving a notion that DNA-PK is involved in the chromosomal translocation. LNCaP cell lines were analyzed for the effect of EGCG and SB on the expression profile of TMPRSS2-ERG. Results In this particular unprecedented study, treatment of the LNCaP cell line with EGCG and Silibilin recapitulated ATM expression and activity and downregulated the fusion transcript appearance. Conclusions These results underscore the therapeutic effect of EGCG and SB in mitigating the exacerbation of the disease with reference to the fusion transcripts.
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Affiliation(s)
- Ammad Ahmad Farooqi
- Institute of Molecular Biology and Biotechnology (IMBB), The University of Lahore, Pakistan
| | - Qaisar Mansoor
- Institute of Biomedical and Genetic Engineering (IBGE), Islamabad, Pakistan
| | - Muhammad Ismail
- Institute of Biomedical and Genetic Engineering (IBGE), Islamabad, Pakistan
| | - Shahzad Bhatti
- Institute of Molecular Biology and Biotechnology (IMBB), The University of Lahore, Pakistan
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Xu XL, Lee TC, Offor N, Cheng C, Liu A, Fang Y, Jhanwar SC, Abramson DH, Cobrinik D. Tumor-associated retinal astrocytes promote retinoblastoma cell proliferation through production of IGFBP-5. THE AMERICAN JOURNAL OF PATHOLOGY 2010; 177:424-35. [PMID: 20508032 DOI: 10.2353/ajpath.2010.090512] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Retinoblastomas consist of cone-like neoplastic cells and diverse non-neoplastic cells whose roles in tumorigenesis have not been defined. Here, we investigated the glial cells that constitute 2% to 3% of the cells in retinoblastoma tumors, including their origin, their relationship to a potential retinoblastoma stem cell population, and their effects on tumor cell proliferation. Retinoblastoma glia consistently expressed the retinal astrocyte marker Pax2 but inconsistently expressed the Müller cell and occasional astrocyte marker CRALBP. Many of the glia expressed the stem cell-associated Sox2 but nevertheless were non-neoplastic as they coexpressed Rb and/or retained two RB1 alleles. Conversely, the glia were distinct from the non-neoplastic cells that strongly expressed the stem cell-associated ABCG2. Adherent Pax2(+),Sox2(+),Rb(+) glia readily grew from explanted retinoblastomas and produced soluble factors that enhanced the proliferation of cocultured retinoblastoma cells. This effect was emulated by normal retinal glia and appeared to be mediated by insulin-like growth factor binding protein-5 (IGFBP-5), as it was mimicked by recombinant IGFBP-5 and mitigated by neutralizing IGFBP-5 antibody. As glia-derived IGFBP-5 was earlier found to promote photoreceptor survival, our findings indicate that retinal astrocytes enhance the proliferation of cone-like retinoblastoma cells by deploying a factor that also provides trophic support to the tumor cells' non-neoplastic counterparts. These observations suggest that a tissue-specific microenvironmental feature cooperates with oncogenic mutations in a cancer cell of origin to promote retinoblastoma tumorigenesis.
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Affiliation(s)
- Xiaoliang L Xu
- Dyson Vision Research Institute, Weill Medical College of Cornell University, New York, New York, USA
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35
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Yang WL, Wu CY, Wu J, Lin HK. Regulation of Akt signaling activation by ubiquitination. Cell Cycle 2010; 9:487-97. [PMID: 20081374 DOI: 10.4161/cc.9.3.10508] [Citation(s) in RCA: 102] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Akt (also known as PKB) signaling orchestrates many aspects of biological functions and, importantly, its deregulation is linked to cancer development. Akt activity is well-known regulated through its phosphorylation at T308 and S473 by PDK1 and mTOrC2, respectively. Although in the last decade the research has been primarily focused on Akt phosphorylation and its role in Akt activation and functions, other posttranslational modifications on Akt have never been reported. Until very recently, a novel posttranslational modification on Akt termed ubiquitination was identified and shown to play an important role in Akt activation. The cancer-associated Akt mutant recently identified in a subset of human cancers displays enhanced Akt ubiquitination, in turn contributing to Akt hyperactivation, suggesting a potential role of Akt ubiquitination in cancers. Thus, this novel posttranslational modification on Akt reveals an exciting avenue that has advanced our current understandings of how Akt signaling activation is regulated.
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Affiliation(s)
- Wei-Lei Yang
- Department of Molecular and Cellular Oncology, The University of Texas M.D. Anderson Cancer Center, Houston, TX, USA
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Na YJ, Farley J, Zeh A, del Carmen M, Penson R, Birrer MJ. Ovarian cancer: markers of response. Int J Gynecol Cancer 2010; 19 Suppl 2:S21-9. [PMID: 19955910 DOI: 10.1111/igc.0b013e3181c2aeb5] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
OBJECTIVES Despite improved knowledge regarding the etiology of ovarian cancer, as well as application of aggressive surgery and chemotherapy, there has been only a modest change in the mortality statistics over the last 30 years. Given these results and the evolution of targeted therapies, there is an increasing need for prognostic and predictive factors to stratify patients for individualized care. Many laboratories have also investigated the specific individual biomarkers correlating them with clinicopathologic characteristics. Unfortunately, the vast majorities of these biomarkers have not proved clinically valuable. In this article, we review published genomic signatures including data generated in our laboratory for their relevance. METHODS Multiple published expression profiling articles were selected for review and discussion. Genomic studies were separated from those with dichotomized survival data and unsupervised analysis to identify discreet subsets of tumors and studies that generated activated pathways. RESULTS The identification of prognostic and predictive individual biomarkers has been common. Few of these have been validated. Genomic profiles have been obtained that distinguish short- from long-term survivors. The relevance of these studies to the large number of patients within the extremes remains unclear. Unsupervised clustering studies of ovarian cancers have identified potential subsets of tumors that reflect different clinical behavior. These studies will require large numbers of independent samples for validation. Another approach has been to identify genes that correlate with patient survival as a continuous variable. These genes are then placed into biologic context using pathway analysis. These pathways provide potential therapeutic targets, and those patients whose tumors express these targets may be most effectively treated by using inhibitors specific for the pathway. CONCLUSIONS There is a major need for prognostic and predictive biomarkers for ovarian cancer. With the development of new genomic technologies, there is an opportunity to identify gene expression signatures that can be used to stratify patients according to their ultimate survival and response to chemotherapy. Large independent sets and robust statistical techniques will be required to fully exploit this approach.
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Affiliation(s)
- Young-Jeong Na
- Comprehensive Gynecologic Cancer Center, Bundang CHA General Hospital, School of Medicine, CHA University, Gyunggido, Korea
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Zoubeidi A, Zardan A, Wiedmann RM, Locke J, Beraldi E, Fazli L, Gleave ME. Hsp27 promotes insulin-like growth factor-I survival signaling in prostate cancer via p90Rsk-dependent phosphorylation and inactivation of BAD. Cancer Res 2010; 70:2307-17. [PMID: 20197463 DOI: 10.1158/0008-5472.can-09-3252] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Hsp27 is highly expressed in castrate-resistant prostate cancer. Although its overexpression confers resistance to androgen ablation and chemotherapy, the mechanisms by which Hsp27 inhibits treatment-induced apoptosis are incompletely defined. Castrate-resistance often correlates with increased activity of autocrine and/or paracrine growth/survival stimulatory loops including the mitogen-activated protein kinase (MAPK) and Akt pathways and insulin-like growth factor (IGF) axis components. Because Hsp27 can be activated by both MAPK and Akt pathways, it is possible that interactions between IGF-I signaling and Hsp27 phosphoactivation function to promote castrate-resistant progression. Here, we report that Hsp27 expression and phosphorylation levels correlate with IGF-I signaling and castrate-resistant progression in human prostate cancer specimens and cell lines. IGF-I induces Hsp27 phosphorylation in a time- and dose-dependent manner via p90Rsk, which interacts directly with and phosphorylates Hsp27 in vitro and in vivo. Conversely, p90Rsk inhibition using short interfering RNA or a dominant negative mutant abolishes IGF-I-induced Hsp27 phosphorylation. Hsp27 overexpression increases IGF-I-induced phosphorylation of Erk, p90Rsk, and Akt. Conversely, Hsp27 knockdown abrogates IGF-I-induced phosphorylation of Erk, p90Rsk, and Akt, thereby destabilizing Bad/14-3-3 complexes and increasing apoptotic rates. These data elucidate the interactions between Hsp27 phosphorylation and the IGF-I receptor signaling pathway and support targeting Hsp27 as a therapeutic strategy for castrate-resistant prostate cancer.
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Affiliation(s)
- Amina Zoubeidi
- Department of Urologic Sciences, The Vancouver Prostate Centre, University of British Columbia, Vancouver, British Columbia, Canada
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Insulin-like growth factor binding protein 5 enhances survival of LX2 human hepatic stellate cells. FIBROGENESIS & TISSUE REPAIR 2010; 3:3. [PMID: 20163708 PMCID: PMC2834615 DOI: 10.1186/1755-1536-3-3] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/06/2009] [Accepted: 02/17/2010] [Indexed: 02/06/2023]
Abstract
Background Expression of insulin-like growth factor binding protein 5 (IGFBP5) is strongly induced upon activation of hepatic stellate cells and their transdifferentiation into myofibroblasts in vitro. This was confirmed in vivo in an animal model of liver fibrosis. Since IGFBP5 has been shown to promote fibrosis in other tissues, the aim of this study was to investigate its role in the progression of liver fibrosis. Methods The effect of IGFBP5 was studied in LX2 cells, a model for partially activated hepatic stellate cells, and in human primary liver myofibroblasts. IGFBP5 signalling was modulated by the addition of recombinant protein, by lentiviral overexpression, and by siRNA mediated silencing. Furthermore, the addition of IGF1 and silencing of the IGF1R was used to investigate the role of the IGF-axis in IGFBP5 mediated effects. Results IGFBP5 enhanced the survival of LX2 cells and myofibroblasts via a >50% suppression of apoptosis. This effect of IGFBP5 was not modulated by the addition of IGF1, nor by silencing of the IGF1R. Additionally, IGFBP5 was able to enhance the expression of established pro-fibrotic markers, such as collagen Iα1, TIMP1 and MMP1. Conclusion IGFBP5 enhances the survival of (partially) activated hepatic stellate cells and myofibroblasts by lowering apoptosis via an IGF1-independent mechanism, and enhances the expression of profibrotic genes. Its lowered expression may, therefore, reduce the progression of liver fibrosis.
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Terada N, Shimizu Y, Yoshida T, Maeno A, Kamba T, Inoue T, Nakamura E, Kamoto T, Ogawa O. Antiandrogen withdrawal syndrome and alternative antiandrogen therapy associated with the W741C mutant androgen receptor in a novel prostate cancer xenograft. Prostate 2010; 70:252-61. [PMID: 19790238 DOI: 10.1002/pros.21058] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
BACKGROUND The mechanisms underlying antiandrogen withdrawal syndrome (AWS) and alternative antiandrogen therapy (AAT) effectiveness were assumed to be mutations in the androgen receptor (AR), which resulted in an altered response to antiandrogens. The aim of the present study was to test this assumption using the novel prostate cancer xenograft model KUCaP-1 harboring the W741C mutant AR (Yoshida et al., Cancer Res 2005; 65(21): 9611-9616). METHODS Mice bearing xenograft tumors were castrated, and the long-term sequential changes in tumor volume were observed. To determine whether AWS was observed in this model, bicalutamide (BCL) was orally administered to the castrated mice and then withdrawn. The effect of flutamide (FLT) on the W741C mutant AR was examined with transactivation assays in vitro and with the oral administration of FLT to non-castrated mice harboring KUCaP-1 in vivo. The AAT efficacy against KUCaP-1 was evaluated by changing BCL with FLT. RESULTS KUCaP-1 regressed significantly after castration and did not re-grow. KUCaP-1 treated with BCL continued to grow even after castration and started regressing 2 months after BCL withdrawal, replicating clinically recognized AWS. The antagonistic effect of FLT against the W741C mutant AR was revealed in vitro and in vivo. AAT with FLT suppressed tumor growth after BCL withdrawal. CONCLUSIONS KUCaP-1 was an entirely androgen-dependent xenograft and mimicked the clinical phenomena of AWS and AAT caused by the agonistic and antagonistic activity of BCL and FLT, respectively. KUCaP-1 could be an in vivo model for screening novel antiandrogens for the treatment of BCL resistant prostate cancer harboring the W741C mutation in the AR.
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Affiliation(s)
- Naoki Terada
- Department of Urology, Kyoto University Graduate School of Medicine, Kyoto, Japan
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40
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Zoubeidi A, Chi K, Gleave M. Targeting the cytoprotective chaperone, clusterin, for treatment of advanced cancer. Clin Cancer Res 2010; 16:1088-93. [PMID: 20145158 PMCID: PMC2822877 DOI: 10.1158/1078-0432.ccr-09-2917] [Citation(s) in RCA: 109] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Many strategies used to kill cancer cells induce stress-responses that activate survival pathways to promote emergence of a treatment resistant phenotype. Secretory clusterin (sCLU) is a stress-activated cytoprotective chaperone up-regulated by many varied anticancer therapies to confer treatment resistance when overexpressed. sCLU levels are increased in several treatment recurrent cancers including castrate resistant prostate cancer, and therefore sCLU has become an attractive target in cancer therapy. sCLU is not druggable with small molecule inhibitors, therefore nucleotide-based strategies to inhibit sCLU at the RNA level are appealing. Preclinical studies have shown that antisense oligonucleotide (ASO) or siRNA knockdown of sCLU have preclinical activity in combination with hormone- and chemotherapy. Phase I and II clinical trial data indicate that the second generation ASO, custirsen (OGX-011), has biologic and clinical activity, suppressing sCLU expression in prostate cancer tissues by more than 90%. A randomized study comparing docetaxel-custirsen to docetaxel alone in men with castrate resistant prostate cancer reported improved survival by 7 months from 16.9 to 23.8 months. Strong preclinical and clinical proof-of-principle data provide rationale for further study of sCLU inhibitors in randomized phase III trials, which are planned to begin in 2010.
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Affiliation(s)
- Amina Zoubeidi
- Department of Urological Sciences, The Vancouver Prostate Centre, University of British Columbia, Vancouver, BC, Canada
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Kumano M, Miyake H, Terakawa T, Furukawa J, Fujisawa M. Suppressed tumour growth and enhanced chemosensitivity by RNA interference targeting Aurora-A in the PC3 human prostate cancer model. BJU Int 2009; 106:121-7. [PMID: 19912186 DOI: 10.1111/j.1464-410x.2009.09047.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
OBJECTIVES To investigate the inhibitory effects of Aurora-A expression in prostate cancer cells on their growth and chemosensitivity. PATIENTS AND METHODS Aurora-A expression in radical prostatectomy specimens obtained from 193 patients were evaluated by immunohistochemical staining. We then established PC3 cells in which the expression vector containing short-hairpin RNA (shRNA) targeting Aurora-A was introduced (PC3/sh-A). The growth and the sensitivity to docetaxel in PC3/sh-A were compared with those in PC3 transfected with control vector alone (PC3/C). RESULTS Immunohistochemistry showed that there were various levels of Aurora-A expression in most prostate cancer tissues, and the expression levels of Aurora-A in prostate cancer were significantly related to Gleason score. Expression levels of both Aurora-A mRNA and protein in PC3/sh-A were approximately 20% of those in PC3/C. In vitro growth of PC3/sh-A was significantly worse than that of PC3/C, and the proportion of PC3/sh-A in the G2-M phase was significantly greater than that of PC3/C. The 50% inhibitory concentration of docetaxel in PC3/sh-A decreased by 67% compared with that in PC3/C. Tumour volume in nude mice injected with PC3/sh-A was significantly smaller than that with PC3/C. Furthermore, treatment of nude mice bearing PC3/sh-A tumour with docetaxel (10 mg/kg, once weekly for 4 weeks) achieved a synergistic cytotoxic effect, despite the lack of an enhanced antitumour effect of docetaxel on PC3/C tumours. CONCLUSIONS The suppression of Aurora-A using shRNA could be a useful therapeutic strategy against androgen-independent prostate cancer, through growth inhibition as well as enhanced chemosensitivity.
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Affiliation(s)
- Masafumi Kumano
- Division of Urology, Kobe University Graduate School of Medicine, Kobe, Japan
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Gleason CE, Ning Y, Cominski TP, Gupta R, Kaestner KH, Pintar JE, Birnbaum MJ. Role of insulin-like growth factor-binding protein 5 (IGFBP5) in organismal and pancreatic beta-cell growth. Mol Endocrinol 2009; 24:178-92. [PMID: 19897600 DOI: 10.1210/me.2009-0167] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
A family of IGF-binding proteins (IGFBP) exerts biological actions both dependent on and independent of IGF-I. A major effector of the insulin/IGF-I signaling pathway, the serine/threonine protein kinase Akt, mediates cellular processes such as glucose uptake, protein synthesis, cell survival, and growth. IGF-I is required for normal organismal growth, and in the pancreatic beta-cell, the insulin/IGF-I signaling pathway is critical for normal and adaptive maintenance of beta-cell mass. Expression of myrAkt1, an activated form of Akt, in the endocrine pancreas drives beta-cell expansion through dramatic increases in both islet and beta-cell size and number. Herein we present a comparative expression profiling of myrAkt1 transgenic islets that demonstrates the increased abundance of transcripts encoding proteins associated with growth, suppression of apoptosis, RNA processing, and metabolism. Although IGFBP5 is identified as a gene induced by Akt1 activation in the beta-cell, Igfbp5 expression is not necessary for myrAkt1 to augment beta-cell size or mass in vivo. However, in the absence of Igfbp5, mice demonstrate an increase in size and mild glucose intolerance. This is accentuated during diet-induced obesity, when Igfbp5-deficient mice have increased adiposity compared with wild-type mice on the same diet. These studies reveal a novel role for Igfbp5 in the control of growth and metabolism.
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Affiliation(s)
- Catherine E Gleason
- University of Pennsylvania School of Medicine, Department of Medicine, Institute for Diabetes, Obesity, and Metabolism, Philadelphia, Pennsylvania 19104, USA
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Terakawa T, Miyake H, Furukawa J, Ettinger SL, Gleave ME, Fujisawa M. Enhanced sensitivity to androgen withdrawal due to overexpression of interleukin-6 in androgen-dependent human prostate cancer LNCaP cells. Br J Cancer 2009; 101:1731-9. [PMID: 19844233 PMCID: PMC2778549 DOI: 10.1038/sj.bjc.6605358] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Background: The objective of this study was to investigate the effects of interleukin-6 (IL-6) overexpression in androgen-dependent prostate cancer LNCaP cells on their phenotype under an androgen-deprived condition. Methods: We established IL-6-overexpressing LNCaP (LNCaP/IL-6) by introducing the expression vector containing IL-6 cDNA. Changes in the phenotype in LNCaP/IL-6 were compared with that in LNCaP transfected with control vector alone (LNCaP/Co). Results: In vitro, the growth of LNCaP/IL-6 was significantly inferior to that of LNCaP/Co under an androgen-deprived condition. Similarly, LNCaP/IL-6 tumour in nude mice rapidly regressed after castration; however, LNCaP/Co tumour growth was transiently inhibited after castration and then continuously accelerated. After androgen withdrawal, expression levels of phosphorylated p44/42 mitogen-activated protein kinase (MAPK) and Akt in LNCaP/IL-6 were markedly upregulated compared with those in LNCaP/Co; however, additional treatment with specific inhibitor of the MAPK or Akt signalling pathway significantly inhibited the growth of LNCaP/IL-6 compared with that of LNCaP/Co. Furthermore, gene microarray analyses showed that androgen deprivation resulted in differential expression of genes involved in growth, apoptotsis and tumorigenesis between LNCaP/Co and LNCaP/IL-6. Conclusion: Excessive secretion of IL-6 by LNCaP cells in an autocrine manner may have a suppressive function in their growth and acquisition of androgen-independent phenotype under an androgen-deprived condition.
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Affiliation(s)
- T Terakawa
- Division of Urology, Department of Surgery, Kobe University Graduate School of Medicine, Kobe 650-0017, Japan
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Johnson SK, Haun RS. Insulin-like growth factor binding protein-5 influences pancreatic cancer cell growth. World J Gastroenterol 2009; 15:3355-66. [PMID: 19610136 PMCID: PMC2712896 DOI: 10.3748/wjg.15.3355] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To investigate the functional significance of insulin-like growth factor binding protein-5 (IGFBP-5) overexpression in pancreatic cancer (PaC).
METHODS: The effects of IGFBP-5 on cell growth were assessed by stable transfection of BxPC-3 and PANC-1 cell lines and measuring cell number and DNA synthesis. Alterations in the cell cycle were assessed by flow cytometry and immunoblot analyses. Changes in cell survival and signal transduction were evaluated after mitogen activated protein kinase and phosphatidylinositol 3-kinase (PI3K) inhibitor treatment.
RESULTS: After serum deprivation, IGFBP-5 expression increased both cell number and DNA synthesis in BxPC-3 cells, but reduced cell number in PANC-1 cells. Consistent with this observation, cell cycle analysis of IGFBP-5-expressing cells revealed accelerated cell cycle progression in BxPC-3 and G2/M arrest of PANC-1 cells. Signal transduction analysis revealed that Akt activation was increased in BxPC-3, but reduced in PANC-1 cells that express IGFBP-5. Inhibition of PI3K with LY294002 suppressed extracellular signal-regulated kinase-1 and -2 (ERK1/2) activation in BxPC-3, but enhanced ERK1/2 activation in PANC-1 cells that express IGFBP-5. When MEK1/2 was blocked, Akt activation remained elevated in IGFBP-5 expressing PaC cells; however, inhibition of PI3K or MEK1/2 abrogated IGFBP-5-mediated cell survival.
CONCLUSION: These results indicate that IGFBP-5 expression affects the cell cycle and survival signal pathways and thus it may be an important mediator of PaC cell growth.
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Locke JA, Fazli L, Adomat H, Smyl J, Weins K, Lubik AA, Hales DB, Nelson CC, Gleave ME, Tomlinson Guns ES. A novel communication role for CYP17A1 in the progression of castration-resistant prostate cancer. Prostate 2009; 69:928-37. [PMID: 19267349 DOI: 10.1002/pros.20940] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
BACKGROUND CYP17A1 is currently a target for total androgen blockade in advanced prostate cancer (CaP) patients. After castration, or removal of testicular androgens, CYP17A1 can act as a rate-limiting enzyme in androgen synthesis from cholesterol or other adrenal precursors within the tumor microenvironment ultimately contributing to disease progression. Herein we provide evidence that CYP17A1 could also be a mediator of cell-to-cell communication within the CaP tumor microenvironment. METHODS CYP17A1 expression was evaluated by immunohistochemical analysis of human tumor sections and Western blot analysis of CaP patients' serum and exosome isolates. CYP17A1 activity assays were conducted in human serum (and positive control human liver and kidney microsomes) using progesterone as a precursor and an LC-MS endpoint. RESULTS These studies revealed that the expression pattern of CYP17A1 is typical of a secretory protein as it is localized to the luminal pole of the cells in exocrine secretory mode. CYP17A1 is expressed in human serum and in fact is elevated in the serum of CaP patients as compared to healthy controls. Serum CYP17A1 activity could not be confirmed, however, verification of CYP17A1 expression in exosomes suggests a role in cell-to-cell communication within the tumor microenvironment. CONCLUSIONS CYP17A1 is a crucial enzyme for de novo androgen synthesis within the tumor microenvironment after removal of testicular androgens by castration. We provide evidence for a novel role for CYP17A1 in serum and further reiterate the importance of targeting this enzyme in CaP progression.
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Affiliation(s)
- Jennifer A Locke
- Department of Urologic Sciences, University of British Columbia, The Prostate Centre at Vancouver General Hospital, Vancouver, British Columbia, Canada
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Zoubeidi A, Rocha J, Zouanat FZ, Hamel L, Scarlata E, Aprikian AG, Chevalier S. The Fer tyrosine kinase cooperates with interleukin-6 to activate signal transducer and activator of transcription 3 and promote human prostate cancer cell growth. Mol Cancer Res 2009; 7:142-55. [PMID: 19147545 DOI: 10.1158/1541-7786.mcr-08-0117] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Androgen withdrawal is the most effective form of systemic therapy for men with advanced prostate cancer. Unfortunately, androgen-independent progression is inevitable, and the development of hormone-refractory disease and death occurs within 2 to 3 years in most men. The understanding of molecular mechanisms promoting the growth of androgen-independent prostate cancer cells is essential for the rational design of agents to treat advanced disease. We previously reported that Fer tyrosine kinase level correlates with the development of prostate cancer and aggressiveness of prostate cancer cell lines. Moreover, knocking down Fer expression interferes with prostate cancer cell growth in vitro. However, the mechanism by which Fer mediates prostate cancer progression remains elusive. We present here that Fer and phospho-Y705 signal transducer and activator of transcription 3 (STAT3) are barely detectable in human benign prostate tissues but constitutively expressed in the cytoplasm and nucleus of the same subsets of tumor cells in human prostate cancer. The interaction between STAT3 and Fer was observed in all prostate cancer cell lines tested, and this interaction is mediated via the Fer Src homology 2 domain and modulated by interleukin-6 (IL-6). Moreover, IL-6 triggered a rapid formation of Fer/gp130 and Fer/STAT3 complexes in a time-dependent manner and consistent with changes in Fer and STAT3 phosphorylation and cytoplasmic/nuclear distribution. The modulation of Fer expression/activation resulted in inhibitory or stimulatory effects on STAT3 phosphorylation, nuclear translocation, and transcriptional activation. These effects translated in IL-6-mediated PC-3 cell growth. Taken together, these results support an important function of Fer in prostate cancer.
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Affiliation(s)
- Amina Zoubeidi
- McGill University Health Center Research Institute, 1650 Cedar Avenue, Montreal, Quebec, Canada H3G 1A4
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Locke JA, Guns ES, Lubik AA, Adomat HH, Hendy SC, Wood CA, Ettinger SL, Gleave ME, Nelson CC. Androgen levels increase by intratumoral de novo steroidogenesis during progression of castration-resistant prostate cancer. Cancer Res 2008; 68:6407-15. [PMID: 18676866 DOI: 10.1158/0008-5472.can-07-5997] [Citation(s) in RCA: 563] [Impact Index Per Article: 35.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Although systemic androgen deprivation prolongs life in advanced prostate cancer, remissions are temporary because patients almost uniformly progress to a state of a castration-resistant prostate cancer (CRPC) as indicated by recurring PSA. This complex process of progression does not seem to be stochastic as the timing and phenotype are highly predictable, including the observation that most androgen-regulated genes are reactivated despite castrate levels of serum androgens. Recent evidence indicates that intraprostatic levels of androgens remain moderately high following systemic androgen deprivation therapy, whereas the androgen receptor (AR) remains functional, and silencing the AR expression following castration suppresses tumor growth and blocks the expression of genes known to be regulated by androgens. From these observations, we hypothesized that CRPC progression is not independent of androgen-driven activity and that androgens may be synthesized de novo in CRPC tumors leading to AR activation. Using the LNCaP xenograft model, we showed that tumor androgens increase during CRPC progression in correlation to PSA up-regulation. We show here that all enzymes necessary for androgen synthesis are expressed in prostate cancer tumors and some seem to be up-regulated during CRPC progression. Using an ex vivo radiotracing assays coupled to high-performance liquid chromatography-radiometric/mass spectrometry detection, we show that tumor explants isolated from CRPC progression are capable of de novo conversion of [(14)C]acetic acid to dihydrotestosterone and uptake of [(3)H]progesterone allows detection of the production of six other steroids upstream of dihydrotestosterone. This evidence suggests that de novo androgen synthesis may be a driving mechanism leading to CRPC progression following castration.
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Affiliation(s)
- Jennifer A Locke
- Department of Urologic Sciences, University of British Columbia, The Prostate Centre at Vancouver General Hospital, Vancouver, British Columbia, Canada
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Hung PS, Kao SY, Shih YH, Chiou SH, Liu CJ, Chang KW, Lin SC. Insulin-like growth factor binding protein-5 (IGFBP-5) suppresses the tumourigenesis of head and neck squamous cell carcinoma. J Pathol 2008; 214:368-76. [PMID: 18085517 DOI: 10.1002/path.2280] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Head and neck squamous cell carcinoma (HNSCC) is a global malignancy. The insulin-like growth factor (IGF) signalling axis plays a critical role in tumourigenesis. This study defined the clinical and functional roles of insulin-like growth factor binding protein-5 (IGFBP-5) in HNSCC. Down-regulation of IGFBP-5 mRNA expression was found during the progression from pre-cancer to HNSCC. The down-regulation in HNSCC was associated with a higher propensity to nodal metastasis. SAS and OECM-1 are HNSCC cells that do, or do not, express IGFBP-5, respectively. Recombinant IGFBP-5 reduced the proliferation of OECM-1 cells and this was exerted mainly through blockade of the IGF pathways. Either IGFBP-5 or IGF-I treatment alone promoted OECM-1 migration, but a combination of treatments generated antagonistic effects. Overexpression of IGFBP-5 reduced the proliferation and anchorage-independent growth of both OECM-1 and SAS cells. Conversely, knockdown of IGFBP-5 expression significantly induced the proliferation and anchorage-independent growth of SAS cells. It also induced the growth of xenografted SAS tumours. SAS transfectants that expressed mutant or truncated IGFBP-5, which lack IGF binding activity, exhibited significantly lower anchorage-independent growth than vector control. This suggests that IGFBP-5 possesses an IGF-independent suppressor function. The suppressive effects of IGFBP-5 on the tumourigenesis of HNSCC might be invaluable to future neoplastic intervention.
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Affiliation(s)
- P-S Hung
- Institute of Oral Biology, School of Dentistry, National Yang-Ming University, Taipei, Taiwan
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49
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Zhang H, Wang J, Pang B, Liang RX, Li S, Huang PT, Wang R, Chung LWK, Zhau HE, Huang C, Zhou JG. PC-1/PrLZ contributes to malignant progression in prostate cancer. Cancer Res 2007; 67:8906-13. [PMID: 17875733 DOI: 10.1158/0008-5472.can-06-4214] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PC-1/PrLZ gene overexpression has been identified to be associated with prostate cancer progression. Previous studies have revealed that PC-1 possesses transforming activity and confers malignant phenotypes to mouse NIH3T3 cells. However, the functional relevance of PC-1 expression changes during prostate cancer development and progression remains to be evaluated. In this study, gain-of-function and loss-of-function analyses in LNCaP and C4-2 cells, respectively, were implemented. Experimental data showed that PC-1 expression was in positive correlation with prostate cancer cell growth and anchor-independent colony formation in vitro, as well as tumorigenicity in athymic BALB/c mice. Moreover, PC-1 expression was also found to promote androgen-independent progression and androgen antagonist Casodex resistance in prostate cancer cells. These results indicate that PC-1 contributes to androgen-independent progression and malignant phenotypes in prostate cancer cells. Furthermore, molecular evidence revealed that PC-1 expression stimulated Akt/protein kinase B signaling pathway, which has been implicated to play important roles in promoting androgen refractory progression in prostate cancer. Increased PC-1 levels in C4-2 cells may represent an adaptive response in prostate cancer, mediating androgen-independent growth and malignant progression. Inhibiting PC-1 expression may represent a novel therapeutic strategy to delay prostate cancer progression.
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Affiliation(s)
- Hui Zhang
- Laboratory of Molecular Oncology, Institute of Biotechnology, Beijing, P. R. China
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50
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An Antibody Targeting the Type I Insulin-like Growth Factor Receptor Enhances the Castration-Induced Response in Androgen-Dependent Prostate Cancer. Clin Cancer Res 2007; 13:6429-39. [DOI: 10.1158/1078-0432.ccr-07-0648] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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