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Combination Treatment Options for Castration-Resistant Prostate Cancer. Prostate Cancer 2021. [DOI: 10.36255/exonpublications.prostatecancer.combinationtreatment.2021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] Open
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2
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Miller D, Ingersoll MA, Lin MF. ErbB-2 signaling in advanced prostate cancer progression and potential therapy. Endocr Relat Cancer 2019; 26:R195-R209. [PMID: 31294537 PMCID: PMC6628717 DOI: 10.1530/erc-19-0009] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Currently, prostate cancer (PCa) remains the most commonly diagnosed solid tumor and the second leading cause of cancer-related deaths in US men. Most of these deaths are attributed to the development of castration-resistant (CR) PCa. ErbB-2 and ErbB family members have been demonstrated to contribute to the progression of this lethal disease. In this review, we focus on updating the role of ErbB-2 in advanced PCa progression and its regulation, including its regulation via ligand activation, miRNAs and protein phosphorylation. We also discuss its downstream signaling pathways, including AKT, ERK1/2 and STATs, involved in advanced PCa progression. Additionally, we evaluate the potential of ErbB-2, focusing on its protein hyper-phosphorylation status, as a biomarker for aggressive PCa as well as the effectiveness of ErbB-2 as a target for the treatment of CR PCa via a multitude of approaches, including orally available inhibitors, intratumoral expression of cPAcP, vaccination and immunotherapy.
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Affiliation(s)
- Dannah Miller
- Department of Biochemistry and Molecular Biology, College of Medicine, University of Nebraska Medical Center, Omaha, NE
- Fred & Pamela Buffett Cancer Center, University of Nebraska Medical Center, Omaha, Nebraska, United States of America
| | - Matthew A. Ingersoll
- Department of Biochemistry and Molecular Biology, College of Medicine, University of Nebraska Medical Center, Omaha, NE
| | - Ming-Fong Lin
- Department of Biochemistry and Molecular Biology, College of Medicine, University of Nebraska Medical Center, Omaha, NE
- Fred & Pamela Buffett Cancer Center, University of Nebraska Medical Center, Omaha, Nebraska, United States of America
- Section of Urology, Department of Surgery, College of Medicine, University of Nebraska Medical Center, Omaha, Nebraska, United States of America
- Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha, Nebraska, United States of America
- College of Pharmacy, Kaohsiung Medical University, Kaohsiung, Taiwan
- Corresponding Author: Ming-Fong Lin, Ph. D., Department of Biochemistry and Molecular Biology, College of Medicine, University of Nebraska Medical Center, 985870 Nebraska Medical Center, Omaha, NE 68198-5870, USA, TEL: (402) 559-6658, FAX: (402) 559-6650, (MFL)
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Gesmundo I, Di Blasio L, Banfi D, Villanova T, Fanciulli A, Favaro E, Gamba G, Musuraca C, Rapa I, Volante M, Munegato S, Papotti M, Gontero P, Primo L, Ghigo E, Granata R. Proton pump inhibitors promote the growth of androgen-sensitive prostate cancer cells through ErbB2, ERK1/2, PI3K/Akt, GSK-3β signaling and inhibition of cellular prostatic acid phosphatase. Cancer Lett 2019; 449:252-262. [PMID: 30790678 DOI: 10.1016/j.canlet.2019.02.028] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2018] [Revised: 02/08/2019] [Accepted: 02/14/2019] [Indexed: 12/13/2022]
Abstract
Prostate cancer (PCa) is one of the most common cancer in men. Although hormone-sensitive PCa responds to androgen-deprivation, there are no effective therapies for castration-resistant PCa. It has been recently suggested that proton pump inhibitors (PPIs) may increase the risk of certain cancers; however, association with PCa remains elusive. Here, we evaluated the tumorigenic activities of PPIs in vitro, in PCa cell lines and epithelial cells from benign prostatic hyperplasia (BPH) and in vivo, in PCa mice xenografts. PPIs increased survival and proliferation, and inhibited apoptosis in LNCaP cells. These effects were attenuated or absent in androgen-insensitive DU-145 and PC3 cells, respectively. Specifically, omeprazole (OME) promoted cell cycle progression, increased c-Myc expression, ErbB2 activity and PSA secretion. Furthermore, OME induced the phosphorylation of MAPK-ERK1/2, PI3K/Akt and GSK-3β, and blunted the expression and activity of cellular prostatic acid phosphatase. OME also increased survival, proliferation and PSA levels in BPH cells. In vivo, OME promoted tumor growth in mice bearing LNCaP xenografts. Our results indicate that PPIs display tumorigenic activities in PCa cells, suggesting that their long-term administration in patients should be carefully monitored.
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Affiliation(s)
- Iacopo Gesmundo
- Division of Endocrinology, Diabetes and Metabolism, Department of Medical Sciences, University of Turin and Città Della Salute e Della Scienza Hospital, Turin, 10126, Italy
| | - Laura Di Blasio
- Candiolo Cancer Institute FPO-IRCCS, Candiolo, Turin, 10060, Italy; Department of Oncology, University of Turin, Turin, Italy
| | - Dana Banfi
- Division of Endocrinology, Diabetes and Metabolism, Department of Medical Sciences, University of Turin and Città Della Salute e Della Scienza Hospital, Turin, 10126, Italy
| | - Tania Villanova
- Division of Endocrinology, Diabetes and Metabolism, Department of Medical Sciences, University of Turin and Città Della Salute e Della Scienza Hospital, Turin, 10126, Italy
| | - Alessandro Fanciulli
- Division of Endocrinology, Diabetes and Metabolism, Department of Medical Sciences, University of Turin and Città Della Salute e Della Scienza Hospital, Turin, 10126, Italy
| | - Enrica Favaro
- Division of Endocrinology, Diabetes and Metabolism, Department of Medical Sciences, University of Turin and Città Della Salute e Della Scienza Hospital, Turin, 10126, Italy
| | - Giacomo Gamba
- Division of Endocrinology, Diabetes and Metabolism, Department of Medical Sciences, University of Turin and Città Della Salute e Della Scienza Hospital, Turin, 10126, Italy
| | - Chiara Musuraca
- Department of Oncology, University of Turin, Turin, Italy; Città Della Salute e Della Scienza Hospital, Turin, 10126, Italy
| | - Ida Rapa
- Department of Oncology, University of Turin, San Luigi Hospital, Orbassano, Turin, 10043, Italy
| | - Marco Volante
- Department of Oncology, University of Turin, San Luigi Hospital, Orbassano, Turin, 10043, Italy
| | - Stefania Munegato
- Division of Urology, Department of Surgical Sciences, University of Turin and Città Della Salute e Della Scienza Hospital, Turin, 10126, Italy
| | - Mauro Papotti
- Department of Oncology, University of Turin, Turin, Italy; Città Della Salute e Della Scienza Hospital, Turin, 10126, Italy
| | - Paolo Gontero
- Division of Urology, Department of Surgical Sciences, University of Turin and Città Della Salute e Della Scienza Hospital, Turin, 10126, Italy
| | - Luca Primo
- Candiolo Cancer Institute FPO-IRCCS, Candiolo, Turin, 10060, Italy; Department of Oncology, University of Turin, Turin, Italy
| | - Ezio Ghigo
- Division of Endocrinology, Diabetes and Metabolism, Department of Medical Sciences, University of Turin and Città Della Salute e Della Scienza Hospital, Turin, 10126, Italy
| | - Riccarda Granata
- Division of Endocrinology, Diabetes and Metabolism, Department of Medical Sciences, University of Turin and Città Della Salute e Della Scienza Hospital, Turin, 10126, Italy.
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Vidhya S, Ramya R, Coral K, Sulochana KN, Bharathidevi SR. Free amino acids hydroxyproline, lysine, and glycine promote differentiation of retinal pericytes to adipocytes: A protective role against proliferative diabetic retinopathy. Exp Eye Res 2018; 173:179-187. [PMID: 29752946 DOI: 10.1016/j.exer.2018.05.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2017] [Revised: 04/28/2018] [Accepted: 05/07/2018] [Indexed: 12/13/2022]
Abstract
AIM This study was conducted to estimate the aminoacid levels in the vitreous of patients with proliferative diabetic retinopathy, and to correlate it with the adiponectin levels. Secondly to test if these amino acids can alter or induce adiponectin levels and its related factors in retinal cells like pericyte as an in vitro model. METHODS All human studies were done as per declaration of Helsinki with institutional approval and after obtaining consent from participating individuals. The vitreous amino acids were estimated in PDR (Proliferative diabetic retinopathy) and MH (Macular Hole) as disease control using HPLC. Bovine retinal pericytes (BRP) were cultured in DMEM/F12 medium and treated with 0.5 mM of any one of the individual amino acids (proline, hydroxyproline, phenylalanine, alanine, serine, glycine, lysine, isoleucine or valine) along with 100 nM insulin for 14 days in high glucose (25 mM) condition. The mRNA expression profile of adipogenic markers (such as Pref1, APN, ZAG and PPARγ), angiogenic markers (VEGF, MMP-2 and MMP-9, TGF-β) and antioxidant markers (Nrf2 and UCP-2) were evaluated by qPCR. Adipogenesis was further confirmed by adipogenesis assay, secretion of adiponectin in medium and triglyceride accumulation by Oil red O staining in Bovine retinal pericytes. RESULTS Amino acids valine (p < 0.004), isoleucine (p < 0.0007), leucine (p < 0.022), serine (p < 0.0007), glycine (p < 0.001), alanine (p < 0.017), phenylalanine (p < 0.013), and lysine (p < 0.001) were significantly elevated in the vitreous of PDR group (n = 30) when compared to macular hole (n = 20). There was a significant positive correlation between serine (p < 0.021), alanine (p < 0.00016), phenylalanine (p < 0.04), isoleucine (p < 0.023), leucine (p < 0.043), and lysine (p < 0.026) with adiponectin level in the vitreous. The amino acids hydroxyproline, proline, lysine, glycine and alanine induced the triglyceride accumulation and expression of Adiponectin. VEGF and MMP-9 expression was decreased with all the amino acids treated and PEDF was significantly increased with phenylalanine treatment. TGFβ mRNA expression showed a significant decrease with proline, alanine, glycine, lysine and isoleucine. The Nrf2 expression was significantly increased in alanine and serine when compared to control. The UCP-2 gene showed a significant increase in proline and lysine treatment. DISCUSSION AND CONCLUSION Our results suggest that amino acids hydroxyproline, proline, lysine, glycine and alanine which are elevated in the PDR vitreous show a tendency to induce adipogenic effects in retinal pericytes by triggering the accumulation of triglycerides and adiponectin. Hence we hypothesize that these aminoacids when elevated along with insulin and glucose can induce metabolic changes in pericytes. The functional implications of these changes tend to be protective as it increases the antioxidant potential and decreases the angiogenesis markers which are potentially pathogenic.
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Affiliation(s)
- S Vidhya
- R.S. Mehta Jain Department of Biochemistry and Cell Biology, Vision Research Foundation, Sankara Nethralaya, Chennai 600 006, India
| | - R Ramya
- R.S. Mehta Jain Department of Biochemistry and Cell Biology, Vision Research Foundation, Sankara Nethralaya, Chennai 600 006, India
| | - K Coral
- R.S. Mehta Jain Department of Biochemistry and Cell Biology, Vision Research Foundation, Sankara Nethralaya, Chennai 600 006, India
| | - K N Sulochana
- R.S. Mehta Jain Department of Biochemistry and Cell Biology, Vision Research Foundation, Sankara Nethralaya, Chennai 600 006, India
| | - S R Bharathidevi
- R.S. Mehta Jain Department of Biochemistry and Cell Biology, Vision Research Foundation, Sankara Nethralaya, Chennai 600 006, India.
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Hsiao YH, Huang YT, Hung CY, Kuo TC, Luo FJ, Yuan TC. PYK2 via S6K1 regulates the function of androgen receptors and the growth of prostate cancer cells. Endocr Relat Cancer 2016; 23:651-63. [PMID: 27492635 DOI: 10.1530/erc-16-0122] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/27/2016] [Accepted: 06/30/2016] [Indexed: 12/30/2022]
Abstract
Androgen receptor (AR) is a steroid hormone receptor that functions as a transcription factor for regulating cell growth and survival. Aberrant AR function becomes a risk factor for promoting the progression of prostate cancer (PCa). In this study, we examined the roles of proline-rich tyrosine kinase 2 (PYK2) and ribosomal S6 kinase 1 (S6K1) in regulating AR expression and activity and growth properties in PCa cells. Compared with normal prostate tissues, PCa tumors exhibited high levels of PYK2 and S6K1 expression. Furthermore, the expression levels of PYK2 and S6K1 were significantly correlated with nuclear AR expression in PCa tissues. We further found the association between PYK2, S6K1, and AR in their protein expression and phosphorylation levels among normal prostate PZ-HPV-7 cells and prostate cancer LNCaP and 22Rv1 cells. Overexpression of the wild-type PYK2 in PZ-HPV-7 and LNCaP cells promoted AR and S6K1 expression and phosphorylation as well as enhanced cell growth. In contrast, expression of the mutated PYK2 or knockdown of PYK2 expression in LNCaP or 22Rv1 cells caused reduced expression or phosphorylation of AR and S6K1 as well as retarded cell growth. Under an androgen-deprived condition, PYK2-promoted AR expression and phosphorylation and PSA production in LNCaP cells can be abolished by knocking down S6K1 expression. In summary, our data suggested that PYK2 via S6K1 activation modulated AR function and growth properties in PCa cells. Thus, PYK2 and S6K1 may potentially serve as therapeutic targets for PCa treatment.
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Affiliation(s)
- Yu-Hsuan Hsiao
- Department of Life ScienceNational Dong Hwa University, Hualien, Taiwan, Republic of China
| | - Yu-Ting Huang
- Department of Life ScienceNational Dong Hwa University, Hualien, Taiwan, Republic of China
| | - Chia-Yu Hung
- Department of Life ScienceNational Dong Hwa University, Hualien, Taiwan, Republic of China
| | - Tzu-Chien Kuo
- Department of Life ScienceNational Dong Hwa University, Hualien, Taiwan, Republic of China
| | - Fuh-Jinn Luo
- Department of PathologyMennonite Hospital, Hualien, Taiwan, Republic of China
| | - Ta-Chun Yuan
- Department of Life ScienceNational Dong Hwa University, Hualien, Taiwan, Republic of China
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6
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Zabalza CV, Adam M, Burdelski C, Wilczak W, Wittmer C, Kraft S, Krech T, Steurer S, Koop C, Hube-Magg C, Graefen M, Heinzer H, Minner S, Simon R, Sauter G, Schlomm T, Tsourlakis MC. HOXB13 overexpression is an independent predictor of early PSA recurrence in prostate cancer treated by radical prostatectomy. Oncotarget 2016; 6:12822-34. [PMID: 25825985 PMCID: PMC4494977 DOI: 10.18632/oncotarget.3431] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2015] [Accepted: 02/24/2015] [Indexed: 01/30/2023] Open
Abstract
HOXB13 is a prostate cancer susceptibility gene which shows a cancer predisposing (G84E) mutation in 0.1–0.6% of males. We analyzed the prognostic impact of HOXB13 expression by immunohistochemistry on a tissue microarray containing more than 12,400 prostate cancers. Results were compared to tumor phenotype, biochemical recurrence, androgen receptor (AR) and prostate specific antigen (PSA) as well as molecular subtypes defined by ERG status and genomic deletions of 3p, 5q, 6q, and PTEN. HOXB13 immunostaining was detectable in 51.7% of 10,216 interpretable cancers and considered strong in 9.6%, moderate in 19.7% and weak in 22.3% of cases. HOXB13 expression was linked to advanced pT stage, high Gleason grade, positive lymph node status (p < 0.0001 each), high pre-operative PSA levels (p = 0.01), TMPRSS2:ERG fusion, PTEN deletions, AR expression, cell proliferation, reduced PSA expression and early PSA recurrence (p < 0.0001 each). The prognostic value of HOXB13 was independent from established parameters including Gleason, stage, nodal stage and PSA. Co-expression analysis identified a subset of tumors with high HOXB13 and AR but low PSA expression that had a particularly poor prognosis. HOXB13 appears to be a promising candidate for clinical routine tests either alone or in combination with other markers, including AR and PSA.
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Affiliation(s)
| | - Meike Adam
- Martini-Clinic, Prostate Cancer Center, University Medical Center Hamburg-Eppendorf, Germany
| | - Christoph Burdelski
- General, Visceral and Thoracic Surgery Department and Clinic, University Medical Center Hamburg-Eppendorf, Germany
| | - Waldemar Wilczak
- Institute of Pathology, University Medical Center Hamburg-Eppendorf, Germany
| | - Corina Wittmer
- Institute of Pathology, University Medical Center Hamburg-Eppendorf, Germany
| | - Stefan Kraft
- Institute of Pathology, University Medical Center Hamburg-Eppendorf, Germany
| | - Till Krech
- Institute of Pathology, University Medical Center Hamburg-Eppendorf, Germany
| | - Stefan Steurer
- Institute of Pathology, University Medical Center Hamburg-Eppendorf, Germany
| | - Christina Koop
- Institute of Pathology, University Medical Center Hamburg-Eppendorf, Germany
| | - Claudia Hube-Magg
- Institute of Pathology, University Medical Center Hamburg-Eppendorf, Germany
| | - Markus Graefen
- Martini-Clinic, Prostate Cancer Center, University Medical Center Hamburg-Eppendorf, Germany
| | - Hans Heinzer
- Martini-Clinic, Prostate Cancer Center, University Medical Center Hamburg-Eppendorf, Germany
| | - Sarah Minner
- Institute of Pathology, University Medical Center Hamburg-Eppendorf, Germany
| | - Ronald Simon
- Institute of Pathology, University Medical Center Hamburg-Eppendorf, Germany
| | - Guido Sauter
- Institute of Pathology, University Medical Center Hamburg-Eppendorf, Germany
| | - Thorsten Schlomm
- Martini-Clinic, Prostate Cancer Center, University Medical Center Hamburg-Eppendorf, Germany.,Department of Urology, Section for Translational Prostate Cancer Research, University Medical Center Hamburg-Eppendorf, Germany
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Schweizer MT, Yu EY. Persistent androgen receptor addiction in castration-resistant prostate cancer. J Hematol Oncol 2015; 8:128. [PMID: 26566796 PMCID: PMC4644296 DOI: 10.1186/s13045-015-0225-2] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2015] [Accepted: 11/10/2015] [Indexed: 02/07/2023] Open
Abstract
It is now understood that persistent activation of the androgen receptor (AR) signaling pathway often underlies the development of castration-resistant prostate cancer (CRPC). This realization led to renewed interest in targeting the AR and ultimately to the development of the potent next-generation AR-directed agents abiraterone and enzalutamide. While these drugs prolong survival in men with CRPC, they are unfortunately not curative. Perhaps not surprisingly, evidence points to persistent AR signaling as one of the key drivers by which resistances to these agents develops. In this context, activation of the AR signaling program can occur through a number of molecular adaptations, including alterations leading to persistent canonical AR signaling (e.g., AR amplification/overexpression, elucidations/concentration of intratumoral androgens), activation of the AR program via feedback pathways (e.g., AKT/mTOR/Pi3K, HER2/Neu), and activation of the AR program via mutation or substitution (e.g., AR ligand binding domain mutation; AR splice variants; glucocorticoid receptor signaling). This review will provide an overview of the more clinical relevant (i.e., druggable) pathways that have been implicated in the emergence of drug resistance in men with CRPC and highlight some of the ongoing efforts towards developing therapeutics to impair these mechanisms.
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Affiliation(s)
- Michael T Schweizer
- Division of Oncology, Department of Medicine, University of Washington/Fred Hutchinson Cancer Research Center, Seattle, WA, 98109, USA.
| | - Evan Y Yu
- Division of Oncology, Department of Medicine, University of Washington/Fred Hutchinson Cancer Research Center, Seattle, WA, 98109, USA.
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Perner S, Cronauer MV, Schrader AJ, Klocker H, Culig Z, Baniahmad A. Adaptive responses of androgen receptor signaling in castration-resistant prostate cancer. Oncotarget 2015; 6:35542-55. [PMID: 26325261 PMCID: PMC4742123 DOI: 10.18632/oncotarget.4689] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2015] [Accepted: 06/04/2015] [Indexed: 12/20/2022] Open
Abstract
Prostate Cancer (PCa) is an important age-related disease being the most common cancer malignancy and the second leading cause of cancer mortality in men in Western countries. Initially, PCa progression is androgen receptor (AR)- and androgen-dependent. Eventually advanced PCa reaches the stage of Castration-Resistant Prostate Cancer (CRPC), but remains dependent on AR, which indicates the importance of AR activity also for CRPC. Here, we discuss various pathways that influence the AR activity in CRPC, which indicates an adaptation of the AR signaling in PCa to overcome the treatment of PCa. The adaptation pathways include interferences of the normal regulation of the AR protein level, the expression of AR variants, the crosstalk of the AR with cytokine tyrosine kinases, the Src-Akt-, the MAPK-signaling pathways and AR corepressors. Furthermore, we summarize the current treatment options with regard to the underlying molecular basis of the common adaptation processes of AR signaling that may arise after the treatment with AR antagonists, androgen deprivation therapy (ADT) as well as for CRPC, and point towards novel therapeutic strategies. The understanding of individualized adaptation processes in PCa will lead to individualized treatment options in the future.
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Affiliation(s)
- Sven Perner
- Section for Prostate Cancer Research, Institute of Pathology, Center for Integrated Oncology Cologne/Bonn, University Hospital of Bonn, Bonn, Germany
| | | | | | - Helmut Klocker
- Division of Experimental Urology, Department of Urology, Medical University of Innsbruck, Austria
| | - Zoran Culig
- Department of Urology, Medical University of Innsbruck, Austria
| | - Aria Baniahmad
- Institute of Human Genetics, Jena University Hospital, Germany
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9
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Muniyan S, Chen SJ, Lin FF, Wang Z, Mehta PP, Batra SK, Lin MF. ErbB-2 signaling plays a critical role in regulating androgen-sensitive and castration-resistant androgen receptor-positive prostate cancer cells. Cell Signal 2015; 27:2261-71. [PMID: 26257301 DOI: 10.1016/j.cellsig.2015.08.002] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2015] [Revised: 07/30/2015] [Accepted: 08/05/2015] [Indexed: 11/16/2022]
Abstract
While androgen deprivation therapy (ADT) reduces tumor burden, autocrine growth factor loops such as human epidermal growth factor receptor 2 (HER2/ErbB-2/neu) have been proposed to contribute to prostate cancer (PCa) survival and relapse. However, the role of ErbB-2 in regulating androgen-sensitive (AS) and castration-resistant (CR) cell proliferation remains unclear. Here, we determined the role of ErbB-2 in PCa progression and survival under steroid-reduced conditions using two independent PCa cell progression models. In AR-positive androgen-independent (AI) PCa cells that exhibit the CR phenotype, ErbB-2 was constitutively activated, compared to corresponding AS PCa cells. In AS LNCaP C-33 cells, androgen-induced ErbB-2 activation through ERK1/2 mediates PCa cell proliferation. Further, the ErbB-2-specific but not EGFR-specific inhibitor suppresses basal and androgen-stimulated cell proliferation and also blocks ERK1/2 activation. ErbB-2 ectopic expression and cPAcP siRNA transfection of LNCaP C-33 cells each increases ErbB-2 tyrosine phosphorylation, correlating with increased AI PSA secretion and cell proliferation. Conversely, trapping ErbB-2 by transfected endoplasmic reticulum-targeting ScFv5R expression vector abolished DHT-induced LNCaP C-33 cell growth. Moreover, inhibition of ErbB-2 but not EGFR in AI LNCaP C-81 and MDA PCa2b-AI PCa cells significantly abolished AI cell growth. In contrast to androgens via ErbB-2/ERK1/2 signaling in AS PCa cells, the inhibition of ErbB-2 abrogated AI cell proliferation by inhibiting the cell survival protein Akt in those AI cells. These results suggest that ErbB-2 is a prominent player in mediating the ligand-dependent and -independent activation of AR in AS and AI/CR PCa cells respectively for PCa progression and survival.
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Affiliation(s)
- Sakthivel Muniyan
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE, USA
| | - Siu-Ju Chen
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE, USA
| | - Fen-Fen Lin
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE, USA
| | - Zhengzhong Wang
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE, USA
| | - Parmender P Mehta
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE, USA
| | - Surinder K Batra
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE, USA; Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha, NE, USA; Department of Pathology, University of Nebraska Medical Center, Omaha, NE, USA
| | - Ming-Fong Lin
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE, USA; Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha, NE, USA; Department of Surgery/Urology, University of Nebraska Medical Center, Omaha, NE, USA; College of Pharmacy, Kaohsiung Medical University, Kaohsiung 807, Taiwan, ROC.
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10
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Muniyan S, Ingersoll MA, Batra SK, Lin MF. Cellular prostatic acid phosphatase, a PTEN-functional homologue in prostate epithelia, functions as a prostate-specific tumor suppressor. BIOCHIMICA ET BIOPHYSICA ACTA 2014; 1846:88-98. [PMID: 24747769 PMCID: PMC4140952 DOI: 10.1016/j.bbcan.2014.04.006] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2014] [Accepted: 04/11/2014] [Indexed: 12/13/2022]
Abstract
The inactivation of tumor suppressor genes (TSGs) plays a vital role in the progression of human cancers. Nevertheless, those ubiquitous TSGs have been shown with limited roles in various stages of diverse carcinogenesis. Investigation on identifying unique TSG, especially for early stage of carcinogenesis, is imperative. As such, the search for organ-specific TSGs has emerged as a major strategy in cancer research. Prostate cancer (PCa) has the highest incidence in solid tumors in US males. Cellular prostatic acid phosphatase (cPAcP) is a prostate-specific differentiation antigen. Despite intensive studies over the past several decades on PAcP as a PCa biomarker, the role of cPAcP as a PCa-specific tumor suppressor has only recently been emerged and validated. The mechanism underlying the pivotal role of cPAcP as a prostate-specific TSG is, in part, due to its function as a protein tyrosine phosphatase (PTP) as well as a phosphoinositide phosphatase (PIP), an apparent functional homologue to phosphatase and tensin homolog (PTEN) in PCa cells. This review is focused on discussing the function of this authentic prostate-specific tumor suppressor and the mechanism behind the loss of cPAcP expression leading to prostate carcinogenesis. We review other phosphatases' roles as TSGs which regulate oncogenic PI3K signaling in PCa and discuss the functional similarity between cPAcP and PTEN in prostate carcinogenesis.
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Affiliation(s)
- Sakthivel Muniyan
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE, USA
| | - Matthew A Ingersoll
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE, USA
| | - Surinder K Batra
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE, USA; Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha, NE, USA
| | - Ming-Fong Lin
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE, USA; Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha, NE, USA; Department of Surgery/Urology, University of Nebraska Medical Center, Omaha, NE, USA; College of Pharmacy, Kaohsiung Medical University, Kaohsiung, Taiwan, ROC.
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11
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A novel function of HER2/Neu in the activation of G2/M checkpoint in response to γ-irradiation. Oncogene 2014; 34:2215-26. [PMID: 24909175 DOI: 10.1038/onc.2014.167] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2013] [Revised: 04/21/2014] [Accepted: 05/06/2014] [Indexed: 12/13/2022]
Abstract
In response to γ-irradiation (IR)-induced DNA damage, activation of cell cycle checkpoints results in cell cycle arrest, allowing time for DNA repair before cell cycle re-entry. Human cells contain G1 and G2 cell cycle checkpoints. While G1 checkpoint is defective in most cancer cells, commonly due to mutations and/or alterations in the key regulators of G1 checkpoint (for example, p53, cyclin D), G2 checkpoint is rarely impaired in cancer cells, which is important for cancer cell survival. G2 checkpoint activation involves activation of ataxia telangiectasia-mutated (ATM)/ATM- and rad3-related (ATR) signalings, which leads to the inhibition of Cdc2 kinase and subsequent G2/M cell cycle arrest. Previous studies from our laboratory show that G2 checkpoint activation following IR exposure of MCF-7 breast cancer cells is dependent on the activation of extracellular signal-regulated protein kinase 1 and 2 (ERK1/2) signaling. As HER receptor tyrosine kinases (RTKs), which have important roles in cell proliferation and survival, have been shown to activate ERK1/2 signaling in response to various stimuli, we investigated the role of HER RTKs in IR-induced G2/M checkpoint response in breast cancer cells. Results of the present studies indicate that IR exposure resulted in a striking increase in the phosphorylation of HER1, HER2, HER3 and HER4 in MCF-7 cells, indicative of activation of these proteins. Furthermore, specific inhibition of HER2 using an inhibitor, short hairpin RNA and dominant-negative mutant HER2 abolished IR-induced activation of ATM/ATR signaling, phosphorylation of Cdc2-Y15 and subsequent induction of G2/M arrest. Moreover, the inhibition of HER2 also abrogated IR-induced ERK1/2 phosphorylation. In contrast, inhibition of HER1 using specific inhibitors or decreasing expression of HER3 or HER4 using short hairpin RNAs did not block the induction of G2/M arrest following IR. These results suggest an important role of HER2 in the activation of G2/M checkpoint response following IR.
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Muniyan S, Chaturvedi NK, Dwyer JG, LaGrange CA, Chaney WG, Lin MF. Human prostatic acid phosphatase: structure, function and regulation. Int J Mol Sci 2013; 14:10438-64. [PMID: 23698773 PMCID: PMC3676848 DOI: 10.3390/ijms140510438] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2013] [Revised: 05/08/2013] [Accepted: 05/08/2013] [Indexed: 11/16/2022] Open
Abstract
Human prostatic acid phosphatase (PAcP) is a 100 kDa glycoprotein composed of two subunits. Recent advances demonstrate that cellular PAcP (cPAcP) functions as a protein tyrosine phosphatase by dephosphorylating ErbB-2/Neu/HER-2 at the phosphotyrosine residues in prostate cancer (PCa) cells, which results in reduced tumorigenicity. Further, the interaction of cPAcP and ErbB-2 regulates androgen sensitivity of PCa cells. Knockdown of cPAcP expression allows androgen-sensitive PCa cells to develop the castration-resistant phenotype, where cells proliferate under an androgen-reduced condition. Thus, cPAcP has a significant influence on PCa cell growth. Interestingly, promoter analysis suggests that PAcP expression can be regulated by NF-κB, via a novel binding sequence in an androgen-independent manner. Further understanding of PAcP function and regulation of expression will have a significant impact on understanding PCa progression and therapy.
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Affiliation(s)
- Sakthivel Muniyan
- Department of Biochemistry and Molecular Biology, College of Medicine, University of Nebraska Medical Center, Omaha, NE 68198, USA; E-Mails: (S.M.); (N.K.C.); (W.G.C.)
| | - Nagendra K. Chaturvedi
- Department of Biochemistry and Molecular Biology, College of Medicine, University of Nebraska Medical Center, Omaha, NE 68198, USA; E-Mails: (S.M.); (N.K.C.); (W.G.C.)
| | - Jennifer G. Dwyer
- College of Medicine, University of Nebraska Medical Center, Omaha, NE 68198, USA; E-Mail:
| | - Chad A. LaGrange
- Department of Surgery/Urology, College of Medicine, University of Nebraska Medical Center, Omaha, NE 68198, USA; E-Mail:
| | - William G. Chaney
- Department of Biochemistry and Molecular Biology, College of Medicine, University of Nebraska Medical Center, Omaha, NE 68198, USA; E-Mails: (S.M.); (N.K.C.); (W.G.C.)
- Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - Ming-Fong Lin
- Department of Biochemistry and Molecular Biology, College of Medicine, University of Nebraska Medical Center, Omaha, NE 68198, USA; E-Mails: (S.M.); (N.K.C.); (W.G.C.)
- Department of Surgery/Urology, College of Medicine, University of Nebraska Medical Center, Omaha, NE 68198, USA; E-Mail:
- Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha, NE 68198, USA
- College of Pharmacy, Kaohsiung Medical University, Kaohsiung 807, Taiwan
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Le Page C, Koumakpayi IH, Péant B, Delvoye N, Saad F, Mes-Masson AM. ErbB2/Her-2 regulates the expression of Akt2 in prostate cancer cells. Prostate 2012; 72:777-88. [PMID: 21932427 DOI: 10.1002/pros.21483] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/18/2011] [Accepted: 08/19/2011] [Indexed: 01/04/2023]
Abstract
BACKGROUND We have previously reported that ErbB family members regulate the signaling pathway leading to Akt and NF-kappaB activation in prostate cancer cells. In this study, the regulation of Akt2 expression in LNCaP, DU145, and PC-3 prostate cancer cell lines was investigated. METHODS Akt-2 expression was analyzed by western-blotting and Q-PCR in cell lines. We also analyzed the Akt-2 protein expression in a tissue microarray from 64 prostate cancer patients. Akt-2 promoter activity was assessed and analyzed by luciferase assay. RESULTS A concomitant over-expression of Her-2 and Akt2 expression was observed by western-blotting and quantitative-PCR in prostate cancer cell lines. A significant correlation between Her-2 and Akt2 protein expression was also observed by immunohistochemistry assay on prostate cancer tissues. In LNCaP cells, over-expression of Akt2 protein and mRNA was decreased by Her-2 pharmacologic inhibitors as well as small interfering RNA (siRNA) specific to Her-2. Cloning of the AKT2 promoter in a luciferase reporter plasmid further showed that Akt2 over-expression in cell lines is associated with increased AKT2 promoter activity suggesting that Her-2 modulates a signaling pathway involving AKT2 gene regulation. CONCLUSION This study reveals a novel mechanism of Akt2 regulation in prostate cancer cells.
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Affiliation(s)
- Cécile Le Page
- Centre de recherche du Centre hospitalier de l'Université de Montréal and Institut du cancer de Montréal, Montreal, Quebec, Canada
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Wu SR, Cheng TS, Chen WC, Shyu HY, Ko CJ, Huang HP, Teng CH, Lin CH, Johnson MD, Lin CY, Lee MS. Matriptase is involved in ErbB-2-induced prostate cancer cell invasion. THE AMERICAN JOURNAL OF PATHOLOGY 2010; 177:3145-58. [PMID: 20971737 DOI: 10.2353/ajpath.2010.100228] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Deregulation of both ErbB-2 signaling and matriptase activity has been associated with human prostate cancer (PCa) progression. In this communication, we investigated the roles of both ErbB-2 signaling in matriptase zymogen activation and matriptase in ErbB-2-induced PCa malignancy. In a human PCa cell progression model, we observed that advanced PCa C-81 LNCaP cells exhibited an aggressive phenotype with increased cell migration and invasion capacity; these cells concurrently showed both enhanced ErbB-2 phosphorylation and increased matriptase zymogen activation compared with parental C-33 LNCaP cells. Moreover, ErbB2 activation, both ligand-dependent (eg, epidermal growth factor treatment) and ligand-independent (eg, overexpression), was able to induce matriptase zymogen activation in this cell line. Inhibition of ErbB-2 activity by either the specific inhibitor, AG825, in epidermal growth factor-treated C-33 LNCaP cells or ErbB-2 knockdown in C-81 LNCaP cells, reduced matriptase activation. These observations were confirmed by similar studies using both DU145 and PC3 cells. Together, these data suggest that ErbB-2 signaling plays an important role in matriptase zymogen activation. ErbB-2-enhanced matriptase activation was suppressed by a phosphatidylinositol 3-kinase inhibitor (ie, LY294002) but not by a MEK inhibitor (ie, PD98059). Suppression of matriptase expression by small hairpin RNA knockdown in ErbB-2-overexpressing LNCaP cells dramatically suppressed cancer cell invasion. In summary, our data indicate that ErbB-2 signaling via the phosphatidylinositol 3-kinase pathway results in up-regulated matriptase zymogen activity, which contributes to PCa cell invasion.
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Affiliation(s)
- Shang-Ru Wu
- Department of Biochemistry and Molecular Biology, College of Medicine, National Taiwan University, R817, 8F, No. 1, Section 1, Jen-Ai Rd, Taipei, Taiwan
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15
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Chuang TD, Chen SJ, Lin FF, Veeramani S, Kumar S, Batra SK, Tu Y, Lin MF. Human prostatic acid phosphatase, an authentic tyrosine phosphatase, dephosphorylates ErbB-2 and regulates prostate cancer cell growth. J Biol Chem 2010; 285:23598-606. [PMID: 20498373 DOI: 10.1074/jbc.m109.098301] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Cellular prostatic acid phosphatase (cPAcP), an authentic tyrosine phosphatase, is proposed to function as a negative growth regulator of prostate cancer (PCa) cells in part through its dephosphorylation of ErbB-2. Nevertheless, the direct interaction between cPAcP and ErbB-2 has not been shown nor the specific dephosphorylation site of ErbB-2 by cPAcP. In this report, our data show that the phosphorylation level of ErbB-2 primarily at Tyr(1221/2) correlates with the growth rate of both LNCaP and MDA PCa2b human PCa cells. Further, cPAcP reciprocally co-immunoprecipitated with ErbB-2 in a non-permissive growth condition. Expression of wild type cPAcP, but not inactive mutant, by cDNA in cPAcP-null LNCaP C-81 cells results in decreased tyrosine phosphorylation of ErbB-2 including Tyr(1221/2). Concurrently, Tyr(317) phosphorylation of p52(Shc), proliferating cell nuclear antigen expression, and cell growth are decreased in these cells. Conversely, decreased cPAcP expression by short hairpin RNA in LNCaP C-33 cells was associated with elevated phosphorylation of ErbB-2 initially at Tyr(1221/2). Its downstream p52(Shc), ERK1/2, Akt, Src, STAT-3, and STAT-5 were activated, and cell proliferation, proliferating cell nuclear antigen, and cyclin D1 expression were increased. Stable subclones of C-33 cells by small interfering PAcP had elevated Tyr(1221/2) phosphorylation of ErbB-2 and exhibited androgen-independent growth and increased tumorigenicity in xenograft female animals. In summary, our data together indicate that in prostate epithelia, cPAcP interacts with and dephosphorylates ErbB-2 primarily at Tyr(1221/2) and hence blocks downstream signaling, leading to reduced cell growth. In PCa cells, decreased cPAcP expression is associated with androgen-independent cell proliferation and tumorigenicity as seen in advanced hormone-refractory prostate carcinomas.
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Affiliation(s)
- Tsai-Der Chuang
- Department of Biochemistry and Molecular Biology, College of Medicine, University of Nebraska Medical Center, Omaha, NE 68198, USA
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Rajendran M, Thomes P, Zhang L, Veeramani S, Lin MF. p66Shc--a longevity redox protein in human prostate cancer progression and metastasis : p66Shc in cancer progression and metastasis. Cancer Metastasis Rev 2010; 29:207-22. [PMID: 20111892 DOI: 10.1007/s10555-010-9213-8] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
p66Shc, a 66 kDa proto-oncogene Src homologous-collagen homologue (Shc) adaptor protein, is classically known in mediating receptor tyrosine kinase signaling and recently identified as a sensor to oxidative stress-induced apoptosis and as a longevity protein in mammals. The expression of p66Shc is decreased in mice and increased in human fibroblasts upon aging and in aging-related diseases, including prostate cancer. p66Shc protein level correlates with the proliferation of several carcinoma cells and can be regulated by steroid hormones. Recent advances point that p66Shc protein plays a role in mediating cross-talk between steroid hormones and redox signals by serving as a common convergence point in signaling pathways on cell proliferation and apoptosis. This article first reviews the unique function of p66Shc protein in regulating oxidative stress-induced apoptosis. Subsequently, we discuss its novel role in androgen-regulated prostate cancer cell proliferation and metastasis and the mechanism by which it mediates androgen action via the redox signaling pathway. The data together indicate that p66Shc might be a useful biomarker for the prognosis of prostate cancer and serve as an effective target for its cancer treatment.
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Affiliation(s)
- Mythilypriya Rajendran
- Department of Biochemistry and Molecular Biology, College of Medicine, University of Nebraska Medical Center, 985870 Nebraska Medical Center, Omaha, NE, 68198-5870, USA
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17
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Tasseff R, Nayak S, Salim S, Kaushik P, Rizvi N, Varner JD. Analysis of the molecular networks in androgen dependent and independent prostate cancer revealed fragile and robust subsystems. PLoS One 2010; 5:e8864. [PMID: 20126616 PMCID: PMC2812491 DOI: 10.1371/journal.pone.0008864] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2009] [Accepted: 12/22/2009] [Indexed: 11/28/2022] Open
Abstract
Androgen ablation therapy is currently the primary treatment for metastatic prostate cancer. Unfortunately, in nearly all cases, androgen ablation fails to permanently arrest cancer progression. As androgens like testosterone are withdrawn, prostate cancer cells lose their androgen sensitivity and begin to proliferate without hormone growth factors. In this study, we constructed and analyzed a mathematical model of the integration between hormone growth factor signaling, androgen receptor activation, and the expression of cyclin D and Prostate-Specific Antigen in human LNCaP prostate adenocarcinoma cells. The objective of the study was to investigate which signaling systems were important in the loss of androgen dependence. The model was formulated as a set of ordinary differential equations which described 212 species and 384 interactions, including both the mRNA and protein levels for key species. An ensemble approach was chosen to constrain model parameters and to estimate the impact of parametric uncertainty on model predictions. Model parameters were identified using 14 steady-state and dynamic LNCaP data sets taken from literature sources. Alterations in the rate of Prostatic Acid Phosphatase expression was sufficient to capture varying levels of androgen dependence. Analysis of the model provided insight into the importance of network components as a function of androgen dependence. The importance of androgen receptor availability and the MAPK/Akt signaling axes was independent of androgen status. Interestingly, androgen receptor availability was important even in androgen-independent LNCaP cells. Translation became progressively more important in androgen-independent LNCaP cells. Further analysis suggested a positive synergy between the MAPK and Akt signaling axes and the translation of key proliferative markers like cyclin D in androgen-independent cells. Taken together, the results support the targeting of both the Akt and MAPK pathways. Moreover, the analysis suggested that direct targeting of the translational machinery, specifically eIF4E, could be efficacious in androgen-independent prostate cancers.
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Affiliation(s)
- Ryan Tasseff
- School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, New York, United States of America
| | - Satyaprakash Nayak
- School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, New York, United States of America
| | - Saniya Salim
- School of Biomedical Engineering, Cornell University, Ithaca, New York, United States of America
| | - Poorvi Kaushik
- School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, New York, United States of America
| | - Noreen Rizvi
- School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, New York, United States of America
| | - Jeffrey D. Varner
- School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, New York, United States of America
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18
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Nicotera TM, Schuster DP, Bourhim M, Chadha K, Klaich G, Corral DA. Regulation of PSA secretion and survival signaling by calcium-independent phopholipase A(2)beta in prostate cancer cells. Prostate 2009; 69:1270-80. [PMID: 19475654 DOI: 10.1002/pros.20968] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
BACKGROUND Serum prostate specific antigen (PSA) levels in prostate cancer patients serve as a useful biomarker for diagnosing and monitoring prostate cancer. Recently, secreted PSA has been characterized as an autocrine survival factor through activation of Akt and induction of AR. In the normal prostate, PSA is secreted in the lumen of prostatic ducts to lyse proteins in the seminal coagulum. METHODS However, the mechanism for constitutive PSA secretion from benign prostate and its transport across the prostate-blood barrier into serum are unknown. Regulation of peptide secretion by iPLA(2)-beta has been reported in non-prostatic tissue and in prostate tissue iPLA(2)-beta is reported to be under androgen regulation. We investigated whether iPLA(2) plays a role for in PSA secretion by comparing iPLA(2) activity and expression in normal prostate epithelial RWPE-1 cells and in LNCaP prostate cancer cells. Expression of the two active iPLA(2)-beta mRNA splice variants, LH-iPLA(2) and SH-iPLA(2), were increased and the inhibitory ankyrin-iPLA(2) isoform was markedly reduced in LNCaP cells as compared to normal prostate epithelial RWPE-1 cells. RESULTS These changes are consistent with a higher enzymatic activity in LNCaP cells. The iPLA(2)-beta-specific inhibitor BEL inhibited PSA secretion and induced apoptosis in LNCaP cells. iPLA(2) knockdown using SiRNA inhibited PSA secretion, downregulated AR and induced apoptosis. Exogenous PSA suppressed BEL-induced apoptosis and neutralizing anti-PSA antibody blocked the survival effect of PSA. CONCLUSIONS These data indicate that iPLA(2)-beta participates in regulating PSA secretion and supports the concept that secreted PSA provides an autocrine survival function in LNCaP cells.
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Affiliation(s)
- Thomas M Nicotera
- Department of Cancer Prevention & Population Sciences, Roswell Park Cancer Institute, Buffalo, New York 14263, USA.
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Javidan J, Deitch AD, Shi XB, de Vere White RW. The Androgen Receptor and Mechanisms for Androgen Independence in Prostate Cancer. Cancer Invest 2009; 23:520-8. [PMID: 16203660 DOI: 10.1080/07357900500202721] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- Javid Javidan
- Department of Urology, University of California Davis, Sacramento, California 95817, USA
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20
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Zhang L, Davis JS, Zelivianski S, Lin FF, Schutte R, Davis TL, Hauke R, Batra SK, Lin MF. Suppression of ErbB-2 in androgen-independent human prostate cancer cells enhances cytotoxic effect by gemcitabine in an androgen-reduced environment. Cancer Lett 2009; 285:58-65. [PMID: 19467571 DOI: 10.1016/j.canlet.2009.04.041] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2009] [Revised: 04/30/2009] [Accepted: 04/30/2009] [Indexed: 12/20/2022]
Abstract
We examined the efficacy of combination treatments utilizing cytotoxic drugs plus inhibitors to members of the ErbB-ERK signal pathway in human prostate cancer (PCa) LNCaP C-81 cells. Under an androgen-reduced condition, 50nM gemcitabine caused about 40% growth suppression on C-81 cells. Simultaneous treatment of gemcitabine plus 10microM AG825 produced 60% suppression (p<0.03); while, 85% growth inhibition (p<0.02) was seen if AG825 was added to gemcitabine-treated cells after a 24h-interval. Our data thus showed that in androgen-reduced conditions, inhibition of ErbB-2 increases the cytotoxic efficacy of gemcitabine in PCa cells. This finding has significant implications in the choice of drugs for combination therapy as well as the order of administration for treating cancer patients.
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Affiliation(s)
- Li Zhang
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, 68198-5870, USA
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21
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Catz SD. Characterization of Rab27a and JFC1 as constituents of the secretory machinery of prostate-specific antigen in prostate carcinoma cells. Methods Enzymol 2008; 438:25-40. [PMID: 18413239 DOI: 10.1016/s0076-6879(07)38003-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/18/2023]
Abstract
Prostate-specific antigen (PSA) and prostate-specific acid phosphatase (PSAP) are produced by prostate carcinoma cells. Their secretion has implications in both prostate cancer diagnosis and progression. The mechanisms involved in PSA and PSAP secretion in response to androgens have remained relatively unknown. The small GTPase Rab27a regulates exocytosis in several tissues. Here, we present methods for the characterization of Rab27a and its effector JFC1/Slp1 as key components of the secretory machinery that regulates exocytosis in prostate carcinoma cells.
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Affiliation(s)
- Sergio D Catz
- Division of Biochemistry, Department of Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, California, USA
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22
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Wu YY, Li H, Lv XY, Wei Q, Li X, Liu XY, Zhou Q, Wei YQ. Overexpression of JKTBP1 induces androgen-independent LNCaP cell proliferation through activation of epidermal growth factor-receptor (EGF-R). Cell Biochem Funct 2008; 26:467-77. [DOI: 10.1002/cbf.1468] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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23
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Chen SJ, Karan D, Johansson SL, Lin FF, Zeckser J, Singh AP, Batra SK, Lin MF. Prostate-derived factor as a paracrine and autocrine factor for the proliferation of androgen receptor-positive human prostate cancer cells. Prostate 2007; 67:557-71. [PMID: 17221842 DOI: 10.1002/pros.20551] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
BACKGROUND The expression of prostate-derived factor (PDF) is significantly elevated in human prostate tumors. We investigate the functional role and signaling of PDF in androgen receptor (AR)-positive human prostate cancer cells. METHODS Transient or stable expression of PDF by cDNA transfection, antisense-mediated gene silencing, media conditioned by PDF-elevated cells, and antibody (Ab) neutralization were employed. RESULTS Elevated endogenous and exogenous expression of PDF and treatment of PDF-enriched media were associated with increased proliferation and clonogenic growth of the cells. On the contrary, knockdown of PDF or addition of PDF neutralizing Ab resulted in diminished proliferation and reduced anchorage-independent growth. Further, ERK1/2 and p90RSK, but not Smad2/3, were activated in PDF-elevated cells as well as in cells treated with PDF-enriched media, while inhibition of ERK1/2 decreased the growth of those cells. CONCLUSION PDF promotes AR-positive prostate tumor progression through upregulating cell proliferation via ERK1/2 signal pathway.
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Affiliation(s)
- Siu-Ju Chen
- Department of Biochemistry and Molecular Biology, College of Medicine, University of Nebraska Medical Center, Omaha, Nebraska 68198, USA
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Gao X, Pang P, Wu S, Yang W, Huang S, Cai Q, Grimes CA. Acid Phosphatase Assay with a Wireless Magnetoelastic Biosensor. ANAL LETT 2007. [DOI: 10.1080/00032710600952580] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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25
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Gao X, Pang P, Wu S, Yang W, Huang S, Cai Q, Grimes CA. Acid Phosphatase Assay with a Wireless Magnetoelastic Biosensor. ANAL LETT 2007. [DOI: 10.1080/00032710601017649] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Agoulnik IU, Weigel NL. Androgen receptor action in hormone-dependent and recurrent prostate cancer. J Cell Biochem 2006; 99:362-72. [PMID: 16619264 DOI: 10.1002/jcb.20811] [Citation(s) in RCA: 98] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The importance of androgens and androgen receptors (AR) in primary prostate cancer is well established. Metastatic disease is usually treated with some form of androgen ablation, which is effective for a limited amount of time. The role of AR in prostate cancers that recur despite androgen ablation therapy is less certain. Most of these tumors express prostate specific antigen (PSA), an androgen-regulated gene; moreover, AR is generally highly expressed in recurrent prostate cancer. We propose that AR continues to play a role in many of these tumors and that it is not only the levels of AR, ligands, and co-regulators, but also the changes in cell signaling that induce AR action in recurrent prostate cancer. These pathways are, therefore, potential therapeutic targets.
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MESH Headings
- Androgens/metabolism
- Animals
- Cell Proliferation
- Gene Expression
- Humans
- Male
- Models, Biological
- Mutation
- Neoplasm Recurrence, Local/genetics
- Neoplasm Recurrence, Local/metabolism
- Neoplasm Recurrence, Local/pathology
- Neoplasms, Hormone-Dependent/genetics
- Neoplasms, Hormone-Dependent/metabolism
- Neoplasms, Hormone-Dependent/pathology
- Prostatic Neoplasms/genetics
- Prostatic Neoplasms/metabolism
- Prostatic Neoplasms/pathology
- Receptors, Androgen/chemistry
- Receptors, Androgen/genetics
- Receptors, Androgen/metabolism
- Signal Transduction
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Affiliation(s)
- Irina U Agoulnik
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, Texas 77030, USA
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Hakariya T, Shida Y, Sakai H, Kanetake H, Igawa T. EGFR signaling pathway negatively regulates PSA expression and secretion via the PI3K-Akt pathway in LNCaP prostate cancer cells. Biochem Biophys Res Commun 2006; 342:92-100. [PMID: 16472761 DOI: 10.1016/j.bbrc.2006.01.106] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2006] [Accepted: 01/20/2006] [Indexed: 11/25/2022]
Abstract
Epidermal growth factor (EGF) and its receptor (EGFR) are involved in hormone-refractory growth and poor prognosis of a subgroup of human prostate cancer. In this communication, we investigated the regulation of PSA by the EGFR signaling pathway using LNCaP C-81 prostate cancer cells. Administration of EGF stimulated the growth of LNCaP C-81 cells, however, PSA expression and secretion were suppressed. An EGFR inhibitor, AG1478, abrogated the PSA suppression effect by EGF, in concurrence with the suppression of tyro-phosphorylation levels of EGFR. Interestingly, the AR level was also decreased in EGF-treated LNCaP C-81 cells. Moreover, LY294002, but not PD98059, inhibited the PSA and AR suppression effect by EGF in concurrence with the suppression of phosphorylation levels of Akt. In conclusion, our results strongly suggest the existence of a novel androgen-independent PSA regulatory mechanism, i.e., the EGFR signaling pathway negatively regulates PSA expression which may be induced by the alteration of AR expression via the PI3K-Akt pathway in LNCaP C-81 cells.
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Affiliation(s)
- Tomoaki Hakariya
- Division of Nephro-Urology, Nagasaki University Graduate School of Biomedical Sciences, 1-7-1 Sakamoto, Nagasaki 852-8501, Japan
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Cao X, Qin J, Xie Y, Khan O, Dowd F, Scofield M, Lin MF, Tu Y. Regulator of G-protein signaling 2 (RGS2) inhibits androgen-independent activation of androgen receptor in prostate cancer cells. Oncogene 2006; 25:3719-34. [PMID: 16449965 DOI: 10.1038/sj.onc.1209408] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Hormones acting through G protein-coupled receptors (GPCRs) can cause androgen-independent activation of androgen receptor (AR) in prostate cancer cells. Regulators of G-protein signaling (RGS) proteins, through their GTPase activating protein (GAP) activities, inhibit GPCR-mediated signaling by inactivating G proteins. Here, we identified RGS2 as a gene specifically downregulated in androgen-independent prostate cancer cells. Expression of RGS2, but not other RGS proteins, abolished androgen-independent AR activity in androgen-independent LNCaP cells and CWR22Rv1 cells. In LNCaP cells, RGS2 inhibited G(q)-coupled GPCR signaling. Expression of exogenous wild-type RGS2, but not its GAP-deficient mutant, significantly reduced AR activation by constitutively activated G(q)Q209L mutant whereas silencing endogenous RGS2 by siRNA enhanced G(q)Q209L-stimulated AR activity. RGS2 had no effect on RGS-insensitive G(q)Q209L/G188S-induced AR activation. Furthermore, extracellular signal-regulated kinase 1/2 (ERK1/2) was found to be involved in RGS2-mediated regulation of androgen-independent AR activity. In addition, RGS2 functioned as a growth suppressor for androgen-independent LNCaP cells whereas androgen-sensitive LNCaP cells with RGS2 silencing had a growth advantage under steroid-reduced conditions. Finally, RGS2 expression level was significantly decreased in human prostate tumor specimens. Taken together, our results suggest RGS2 as a novel regulator of AR signaling and its repression may be an important step during prostate tumorigenesis and progression.
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Affiliation(s)
- X Cao
- Department of Pharmacology, Creighton University School of Medicine, Omaha, NE 68178, USA
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29
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Shi Y, Chatterjee SJ, Brands FH, Shi SR, Pootrakul L, Taylor CR, Datar R, Cote RJ. Role of coordinated molecular alterations in the development of androgen-independent prostate cancer: an in vitro model that corroborates clinical observations. BJU Int 2006; 97:170-8. [PMID: 16336351 DOI: 10.1111/j.1464-410x.2006.05857.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
OBJECTIVE To investigate the role of potential downstream targets of HER-2/neu, including the cell-cycle regulator p27, proliferation-associated protein Ki-67, apoptosis inhibitor Bcl-2, and signal-transduction molecule Akt (which is associated with cell survival), as the development of androgen-independent prostate cancer (AIPC) in patients who are initially responsive to androgen-ablation therapy (AAT) is a significant clinical problem. PATIENTS AND METHODS Earlier studies showed that high levels of HER-2/neu tyrosine kinase receptor expression as assessed by immunohistochemistry were significantly associated with the development of AIPC, and we hypothesised that HER-2/neu overexpression provides an alternative proliferative stimulus upon androgen depletion. We established a unique clinical model system, comprising patients who received no AAT, or who had preoperative AAT, or those with advanced tumours resistant to AAT. To test our hypothesis in vitro, we stably transfected full-length HER-2/neu cDNA in androgen-responsive LNCaP cells and examined the effects of HER-2/neu overexpression on cell proliferation, apoptosis, androgen-receptor activation, and Akt phosphorylation upon androgen deprivation by using immunohistochemistry and Western blot technique. RESULTS p27 expression was initially induced on exposure to AAT, and significantly decreased in AIPC (P < 0.001). There was also a significant increase in the Ki-67 index in AIPC (P = 0.001). Elevated Bcl-2 expression was closely associated with AAT (P = 0.002), suggesting that Bcl-2 expression is induced on initial exposure to AAT. Further, Bcl-2 expression was highest in hormone-resistant cancers (P < 0.001). Using the HER-2/neu transfected cell-line model, we confirmed the mechanistic basis of the clinical observations which elucidate the pathway leading to HER-2/neu-mediated androgen independence. On androgen deprivation, the HER-2/neu transfected cells had higher proliferation rates, lower G1 arrest, inhibited p27 up-regulation, a lower apoptotic index, and higher Bcl-2, prostate-specific antigen and phosphorylated Akt expression than the mock-transfected LNCaP cells. CONCLUSION This study suggests that prostate cancer cells undergo a series of coordinated changes after exposure to AAT, which eventually result in the development of androgen independence. Further, in support of previous results, it appears that a major factor in this process is the induction of HER-2/neu overexpression, which occurs after initial exposure to AAT. HER-2/neu may contribute to the development of androgen independence through: (i) maintaining cell proliferation; (ii) inhibiting apoptosis; and/or (iii) inducing AR activation in a ligand-independent fashion. These effects may be mediated, at least in part, through activation of the PI3K/Akt pathway.
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Affiliation(s)
- Yan Shi
- Department of Pathology, University of Southern California Keck School of Medicine, Los Angeles, CA 90033, USA
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Le Page C, Koumakpayi IH, Lessard L, Saad F, Mes-Masson AM. Independent role of phosphoinositol-3-kinase (PI3K) and casein kinase II (CK-2) in EGFR and Her-2-mediated constitutive NF-kappaB activation in prostate cancer cells. Prostate 2005; 65:306-15. [PMID: 16015604 DOI: 10.1002/pros.20291] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
BACKGROUND Recent research has highlighted the potential role of EGFR and Her-2 in the constitutive activation of NF-kappaB (NF-kappaB) in prostate cancer cells, although the mechanism by which these receptors activate NF-kappaB in these cells remains unclear. METHODS AND RESULTS Using pharmacological and genetic approaches we show that in PC-3 cells, EGFR and Her-2 are involved in the constitutive activation of NF-kappaB through two different mechanisms. EGFR activates NF-kappaB through the PI3K/Akt pathway that leads to the phosphorylation of IkappaBalpha on serines 32 and 36, thereby promoting the nuclear translocation of the p65 subunit. In contrast, Her-2 activates NF-kappaB through Casein Kinase II (CK-2) activation independently of IkappaBalpha phosphorylation on serines 32 and 36. CONCLUSIONS Our study not only directly clarifies the signaling pathways involved in NF-kappaB activation in prostate cancer cell lines and but also provides a framework for further studies in the clinical characterization and management of prostate cancer.
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Affiliation(s)
- Cécile Le Page
- Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CR-CHUM), 1560 rue Sherbrooke est, Montréal, Québec, Canada
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Johnson J, Ellis B, Noack D, Seabra M, Catz S. The Rab27a-binding protein, JFC1, regulates androgen-dependent secretion of prostate-specific antigen and prostatic-specific acid phosphatase. Biochem J 2005; 391:699-710. [PMID: 16004602 PMCID: PMC1276972 DOI: 10.1042/bj20050380] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2005] [Revised: 06/29/2005] [Accepted: 07/08/2005] [Indexed: 11/17/2022]
Abstract
Two of the major proteins secreted by the prostate epithelium secretory cells are PSA (prostate-specific antigen) and PSAP (prostatic-specific acid phosphatase). The molecules involved in the secretory machinery of PSA and PSAP, and the regulation of this machinery, remain unknown. In the present paper, we provide evidence that JFC1 [synaptotagmin-like protein (slp1)], a Rab27a- and PtdIns(3,4,5)P3-binding protein, regulates the androgen-dependent secretion of PSAP and PSA in human LNCaP prostate carcinoma cells. Androgen-dependent PSAP secretion was significantly inhibited in cells that expressed the C2A domain of JFC1 [PtdIns(3,4,5)P3-binding-domain], but was unaffected by JFC1 overexpression. Conversely, PSA secretion was not inhibited by the C2A domain of JFC1. We show, using immunofluorescence analysis, that JFC1 co-localizes with PSAP, but rarely with PSA, in prostate granules, suggesting that JFC1 is part of the PSAP secretory machinery. However, PSA secretion was significantly increased in LNCaP cells that overexpressed JFC1, indicating that the secretion of PSA is susceptible to variations in the intracellular concentration of JFC1. Both PSAP and PSA secretion was increased by overexpression of wild-type Rab27a or the constitutively active Rab27aQ78L. The secretion of PSA was partially inhibited in the presence of LY294002, while the secretion of PSAP was completely abolished by the PI3K (phosphoinositide 3-kinase) inhibitor. This supports the view that PI3K plays a differential role in the secretion of prostate secretory markers. In conclusion, we present evidence that JFC1 differentially regulates the secretion of PSAP and PSA, and that Rab27a and PI3K play a central role in the exocytosis of prostate-specific markers.
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Key Words
- exocytosis
- phosphoinositide 3-kinase (pi3k)
- prostate-specific antigen (psa)
- prostatic-specific acid phosphatase (psap)
- synaptotagmin-like protein
- vesicular trafficking
- dsred, red fluorescent protein from discosoma sp.
- eea1, early endosome antigen 1
- egfp, enhanced green fluorescent protein
- nf-κb, nuclear factor κb
- pi3k, phosphoinositide 3-kinase
- pip3, ptdins(3,4,5)p3
- psa, prostate-specific antigen
- psap, prostate-specific acid phosphatase
- slp, synaptotagmin-like protein
- syt, synaptotagmin
- t-snare, target-associated soluble n-ethylmaleimide-sensitive fusion protein attachment protein receptor
- vamp-2, vesicle-associated membrane protein-2
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Affiliation(s)
- Jennifer L. Johnson
- *Division of Biochemistry, Department of Molecular and Experimental Medicine, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, U.S.A
| | - Beverly A. Ellis
- *Division of Biochemistry, Department of Molecular and Experimental Medicine, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, U.S.A
| | - Deborah Noack
- *Division of Biochemistry, Department of Molecular and Experimental Medicine, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, U.S.A
| | - Miguel C. Seabra
- †Cell and Molecular Biology Section, Division of Biomedical Sciences, Faculty of Medicine, Imperial College London, London SW7 2AZ, U.K
| | - Sergio D. Catz
- *Division of Biochemistry, Department of Molecular and Experimental Medicine, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, U.S.A
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Stewart LV, Lyles B, Lin MF, Weigel NL. Vitamin D receptor agonists induce prostatic acid phosphatase to reduce cell growth and HER-2 signaling in LNCaP-derived human prostate cancer cells. J Steroid Biochem Mol Biol 2005; 97:37-46. [PMID: 16076555 DOI: 10.1016/j.jsbmb.2005.06.011] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
We have previously shown that concentrations of 1alpha,25-dihydroxyvitamin D(3) (1,25D) that induce G(0)/G(1) cell cycle arrest in androgen-dependent LNCaP prostate cancer cells also decrease expression of c-Myc, a proto-oncogene that stimulates progression from G(1) to S phase of the cell cycle. Since both c-Myc expression and cell cycle progression are regulated by tyrosine kinase activation, we examined the ability of 1,25D to alter tyrosine kinase signaling in LNCaP cells and the androgen-independent LNCaP C81 (C81 LN) cell line. 1,25D selectively reduced protein tyrosine phosphorylation within both the LNCaP and C81 LN cells. This reduction in tyrosine kinase signaling appears to result from elevated levels of cellular prostatic acid phosphatase (PAcP). Western blots and biochemical assays revealed 1,25D increases the level of active PAcP in both cell lines. In addition, 1,25D decreased tyrosine phosphorylation of HER-2, an EGFR family member inactivated by PAcP, and the HER-2 downstream adaptor protein p52 Shc in C81 LN cells. Inhibition of HER-2 signaling by AG825 reduces growth of C81 LN cells and the parental LNCaP cells. These data therefore suggest that 1,25D-mediated decreases in LNCaP and C81 LN cell growth are in part due to decreases in tyrosine kinase signaling that result from up-regulation of PAcP.
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Affiliation(s)
- LaMonica V Stewart
- Department of Molecular and Cellular Biology, Baylor College of Medicine, 1 Baylor Plaza, Houston, TX 77030, USA
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33
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Le Page C, Koumakpayi IH, Lessard L, Mes-Masson AM, Saad F. EGFR and Her-2 regulate the constitutive activation of NF-kappaB in PC-3 prostate cancer cells. Prostate 2005; 65:130-40. [PMID: 15880609 DOI: 10.1002/pros.20234] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
BACKGROUND The mechanism through which NF-kappaB (NF-kappaB) is constitutively activated in prostate cancer cells remains unclear. We investigated whether members of the ErbB family of epidermal growth factor receptors (EGFR) are involved in the constitutive activation of NF-kappaB in prostate cancer cell lines. METHODS AND RESULTS EGFR, Her-2, and ErbB3 are expressed and constitutively activated in PC-3, DU145, and LNCaP prostate cancer cells lines. Using several pharmacological ErbB inhibitors, we demonstrate that EGFR and Her-2 are involved in the constitutive activation of NF-kappaB in PC-3 cells through two different mechanisms. EGFR activates NF-kappaB through the phosphorylation of IkappaBalpha on serines 32/36 thereby influencing the nuclear translocation of the p65 subunit. In contrast, Her-2 activates NF-kappaB independently of IkappaBalpha phosphorylation on serines 32/36. CONCLUSION This study directly implicates ErbB receptors in the activation of NF-kappaB in PC-3 prostate cancer cells.
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Affiliation(s)
- Cécile Le Page
- Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CR-CHUM) and Institut du Cancer de Montréal, Quebec, Canada
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Liu Y, Majumder S, McCall W, Sartor CI, Mohler JL, Gregory CW, Earp HS, Whang YE. Inhibition of HER-2/neu kinase impairs androgen receptor recruitment to the androgen responsive enhancer. Cancer Res 2005; 65:3404-9. [PMID: 15833875 DOI: 10.1158/0008-5472.can-04-4292] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Advanced prostate cancer invariably recurs despite androgen deprivation therapy. The androgen receptor (AR) likely plays a key role in this progression and in the continued survival and proliferation of prostate cancer cells in the low androgen environment. Cross-talk with growth factor receptors, such as epidermal growth factor receptor (EGFR) family, has been postulated as a potential mechanism to activate AR in recurrent prostate cancer. We have investigated the role of HER-2/neu (ErbB-2) tyrosine kinase in AR function by characterizing the effect of inhibiting endogenous HER-2 activity in LNCaP cells. We used two independent methods, expression of intracellular single-chain antibody against HER-2 and treatment with a novel dual EGFR/HER-2 kinase inhibitor GW572016 (lapatinib). Expression of intracellular HER-2 antibody scFv-5R and treatment with GW572016 inhibited HER-2 signaling. This HER-2 inhibition led to impairment of AR-mediated functions, such as androgen-stimulated growth and the induction of endogenous prostate-specific antigen (PSA) mRNA and protein. Androgen-stimulated recruitment of AR and histone acetylation at the androgen responsive enhancer of the PSA gene, detected by chromatin immunoprecipitation analysis, were impaired by HER-2 inhibition. GW572016 was more potent in its ability to inhibit PSA expression and AR recruitment and histone acetylation than the EGFR-selective kinase inhibitor ZD1839 (gefitinib), consistent with the HER-2 kinase playing the major role in AR regulation. These results show that HER-2 signaling is required for optimal transcriptional activity of AR in prostate cancer cells and suggest that HER-2 inhibition may provide a novel strategy to disrupt AR function in prostate cancer.
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Affiliation(s)
- Yuanbo Liu
- Lineberger Comprehensive Cancer Center, Department of Radiation Oncology, University of North Carolina, 102 Mason Farm Road, Chapel Hill, NC 27599, USA
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35
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Hu YP, Venkateswarlu S, Sergina N, Howell G, St Clair P, Humphrey LE, Li W, Hauser J, Zborowska E, Willson JKV, Brattain MG. Reorganization of ErbB family and cell survival signaling after Knock-down of ErbB2 in colon cancer cells. J Biol Chem 2005; 280:27383-92. [PMID: 15888451 DOI: 10.1074/jbc.m414238200] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The role of the ErbB family in supporting the malignant phenotype was characterized by stable transfection of a single chain antibody (ScFv5R) against ErbB2 containing a KDEL endoplasmic reticulum retention sequence into GEO human colon carcinoma cells. The antibody traps ErbB2 in the endoplasmic reticulum, thereby down-regulating cell surface ErbB2. The transfected cells showed inactivation of ErbB2 tyrosine phosphorylation and reduced heterodimerization of ErbB2 and ErbB3. This resulted in greater sensitivity to apoptosis induced by growth deprivation and delayed tumorigenicity in vivo. Furthermore, decreased heterodimerization of ErbB2 and ErbB3 led to a reorganization in ErbB function in transfected cells as heterodimerization between epidermal growth factor receptor (EGFR) and ErbB3 increased, whereas ErbB3 activation remained almost the same. Importantly, elimination of ErbB2 signaling resulted in an increase in EGFR expression and activation in transfected cells. Increased EGFR activation contributed to the sustained cell survival in transfected cells.
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Affiliation(s)
- Yi Peter Hu
- Department of Pharmacology and Therapeutics, Roswell Park Cancer Institute, Buffalo, New York 14263, USA
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Abstract
PURPOSE This is part 1 of a 2-part review. Research into the molecular mechanisms underlying the various aspects of prostate cancer (PCa) requires the use of in vivo and in vitro model systems. In the last few years many new cell lines have been established by investigators from primary tissue sources and clonal derivatives of previously established lines. Therefore, the purpose of this 2-part review is to catalogue the current human cell lines developed for PCa research, as reported in the literature. Part 1 includes tissue culture cell lines derived from metastases, primary tumors and nonadenocarcinomas that were established without the use of transgenes. It also includes a section describing lines that have been contaminated with other lines, shown not to be of prostatic origin or whose identity is being challenged. MATERIALS AND METHODS Prostate cell lines included in this review were identified by extensive searching of the literature using several strategies, including PubMed searches and book chapter reviews. RESULTS In total we describe the derivation, phenotype, genotype and characterization of molecular markers expressed by approximately 200 lines and sublines used in PCa research, including those derived from primary tumors, metastases and normal prostate tissue. We paid particular attention to the expression of prostate specific antigen, androgen receptor, cytokeratins and other molecular markers used to indicate the status of PCa and the prostatic lineage of a given line. In an attempt to provide PCa researchers with a resource of information regarding new and established cell lines we have also created an online database of these PCa cell lines freely accessible via the World Wide Web at http://www.CaPCellLines.com. The web based interface allows researchers to peruse and print information regarding cell lines, add new cell lines and update or add new information regarding established cell lines. CONCLUSIONS This compendium of cell lines currently used in PCa research combined with access to our on-line database provides researchers with a continually updated and valuable resource for investigating the molecular mechanisms of PCa.
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Affiliation(s)
- R E Sobel
- Genome Sciences Centre, British Columbia Cancer Agency, Vancouver, British Columbia, Canada.
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37
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Bao BY, Hu YC, Ting HJ, Lee YF. Androgen signaling is required for the vitamin D-mediated growth inhibition in human prostate cancer cells. Oncogene 2004; 23:3350-60. [PMID: 15048085 DOI: 10.1038/sj.onc.1207461] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Epidemiological data on prostate cancer incidence has suggested that vitamin D deficiency may be a risk factor for prostate cancer. The antiproliferative activity of 1alpha, 25-dihydroxyvitamin D3 (1,25-VD) and its analogues has been demonstrated in many prostate cancer models, yet the detailed mechanisms underlying this protective effect of vitamin D remain to be determined. Here, we demonstrate that two androgen receptor (AR)-positive prostate cancer cell lines, LNCaP and CWR22R, are more sensitive to the growth inhibitory effects of 1,25-VD compared to the AR-negative prostate cancer cell lines, PC-3 and DU 145. 1,25-VD treatment inhibited cyclin-dependent kinase 2 (cdk2) activity and induced G0/G1 arrest. Interestingly, we also found that 1,25-VD treatment induced the expression of AR, and that the onset of the G0/G1 arrest in LNCaP and CWR22R cells is correlated with the onset of increasing expression of AR. This implies that the antiproliferative actions of 1,25-VD in AR-positive prostate cancer might be mediated through AR. Furthermore, a reduction in 1,25-VD-mediated growth inhibition was observed when AR signaling was blocked by antiandrogens, AR RNA interference, or targeted disruption of AR. Taken together, our data suggest that the androgen/AR signaling plays an important role in the antiproliferative effects of 1,25-VD and restoration of androgen responsiveness by 1,25-VD might be beneficial for the treatment of hormone-refractory prostate cancer patients.
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Affiliation(s)
- Bo-Ying Bao
- Department of Urology, University of Rochester, Rochester, NY 14642, USA
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38
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Shi XB, Ma AH, Tepper CG, Xia L, Gregg JP, Gandour-Edwards R, Mack PC, Kung HJ, deVere White RW. Molecular alterations associated with LNCaP cell progression to androgen independence. Prostate 2004; 60:257-71. [PMID: 15176055 DOI: 10.1002/pros.20039] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
BACKGROUND There is no effective therapy currently available for androgen-independent (AI) prostate cancer (CaP). This is largely due to lack of information about the molecular mechanisms by which androgen-dependent tumor cells progress to androgen independence. In this study, we investigated molecular alterations occurring in AI LNCaP cells. METHODS We established and characterized three AI LNCaP sublines that exhibited a wide range of cytogenetic alterations. In order to understand why androgen-sensitive LNCaP cells can survive in an androgen-deprived environment, we analyzed the expression of signaling proteins associated with proliferation and survival of AI cells. In addition, gene expression profiling was performed to gain insight into molecular alterations in these LNCaP sublines. RESULTS These LNCaP sublines exhibited heightened levels of androgen receptor (AR), HER2, MAPK, serine 473-phosphorylated Akt, and Bcl-2, implicating these proteins as mediators of AI growth. Gene expression profiling identified a common set of 66 genes that were differentially expressed in all three sublines compared to the parental LNCaP cells. Of these, 32 were apparently androgen regulated, while the remainder comprised an expression signature specific for androgen independence. CONCLUSION We have developed AI LNCaP cell models and identified several genes that are specifically expressed in these models. Elucidating the relative importance of these genetic changes will help define the molecular mechanism by which CaP progresses to androgen independence.
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Affiliation(s)
- Xu-Bao Shi
- Department of Urology, University of California, Davis, School of Medicine, Sacramento, California 95817, USA
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Lee MS, Igawa T, Lin MF. Tyrosine-317 of p52(Shc) mediates androgen-stimulated proliferation signals in human prostate cancer cells. Oncogene 2004; 23:3048-58. [PMID: 14990987 DOI: 10.1038/sj.onc.1207451] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The involvement of tyrosine phosphorylation signaling pathways in steroid-induced cell proliferation has received much attention. However, the adaptor molecule that mediates this interaction remains to be identified. In this communication, we identify p52(Shc) as the mediator between tyrosine phosphorylation signaling and steroid signaling in steroid-responsive cell proliferation. Although the different LNCaP prostate cancer cells, C-33, C-51 and C-81, express similar levels of functional androgen receptor (AR), they exhibit different levels of androgen sensitivity. C-33 cell proliferation is highly responsive to the presence of androgens, whereas C-51 cell proliferation is comparatively less responsive to androgens. In contrast, C-81 cell proliferation is independent of androgens. In these cells, tyrosine phosphorylation levels of both p52(Shc) and ErbB-2 were greatest in C-81 cells, comparatively less in C-51 cells and weaker in C-33 cells. The levels and activity of protein tyrosine phosphatase, cellular prostatic acid phosphatase, decreased correspondingly in those cells. In both androgen-independent, rapidly growing C-81 and ErbB-2 cDNA-transfected C-33 cells, p52(Shc) was hyperphosphorylated at Tyr317 (Y317). Conversely, p52(Shc) tyrophosphorylation was decreased in prostatic acid phosphatase cDNA-transfected stable subclones of C-81 cells, which restore androgen-sensitive proliferation and leads to slow growth rates. In C-33 cells, androgen-stimulated cell proliferation correlated with tyrophosphorylation of ErbB-2 and increased phosphorylation of p52(Shc) at Y317, but not at Y239, differing from phosphorylation patterns associated with epidermal growth factor (EGF) stimulation. Furthermore, overexpression of a mutant of p52(Shc), that is Y317F, blocks Y317 phosphorylation of endogenous p52(Shc) and abolishes androgen-stimulated proliferation, but not EGF-stimulated proliferation. Thus, Y317 of p52(Shc) serves as an important regulatory site that allows tyrosine phosphorylation pathways to moderate androgen sensitivity in human prostate cancer cells.
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Affiliation(s)
- Ming-Shyue Lee
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, 984525 Nebraska Medical Center, Omaha, NE 68198-4525, USA
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Luchter-Wasylewska E, Iciek M. Positive cooperativity in substrate binding of human prostatic acid phosphatase entrapped in AOT–isooctane–water reverse micelles. J Colloid Interface Sci 2004; 273:632-7. [PMID: 15082403 DOI: 10.1016/j.jcis.2004.01.075] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2003] [Accepted: 01/29/2004] [Indexed: 10/26/2022]
Abstract
The kinetics of 1-naphthyl phosphate and phenyl phosphate hydrolysis, catalyzed by human prostatic acid phosphatase (PAP) entrapped in AOT-isooctane-water reverse micelles, has been studied over surfactant hydration degree (w0) range 5 to 35. Continuous spectrophotometric acid phosphatase assays, previously prepared, were employed. PAP was catalytically active over the whole w0 studied range. In order to determine steady-state reaction constants the experimental data were fitted to Hill rate equation. Positive cooperativity in substrate binding was observed, as it was earlier found in aqueous solutions. The extent of cooperativity (expressed as the value of the Hill cooperation coefficient h) increased from 1 to 4, when the micellar water-pool size was growing, at fixed enzyme concentration. In the plots of catalytic activity (kcat) versus w0, the maxima have been found at w0=10 (pH 5.6) and 23 (pH 3.8). It is suggested that catalytically active monomeric and dimeric PAP forms are entrapped in reverse micelles of w0=10 and 23, respectively.
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Affiliation(s)
- Ewa Luchter-Wasylewska
- Institute of Medical Biochemistry, Jagiellonian University, Collegium Medicum, Kopernika 7, 31-034 Kraków, Poland.
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Hernes E, Fosså SD, Berner A, Otnes B, Nesland JM. Expression of the epidermal growth factor receptor family in prostate carcinoma before and during androgen-independence. Br J Cancer 2004; 90:449-54. [PMID: 14735192 PMCID: PMC2410152 DOI: 10.1038/sj.bjc.6601536] [Citation(s) in RCA: 121] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Novel palliative strategies for patients with androgen-independent prostate cancer (AIPC) include targeting the epidermal growth factor receptor (EGFR) family. The aim of the present study was to investigate intrapatient changes of EGFRs during the development of AIPC. In total, 106 symptomatic AIPC patients were identified in whom prostatic biopsies (adenocarcinoma) were available both before the start of androgen deprivation (PRTR biopsy) and after the development of AIPC (AIPC biopsy). All four known subgroups of the EGFR family were determined by immunohistochemistry (IHC): c-erbB-1 (EGFR), c-erbB-2 (HER2/neu), c-erbB-3 (HER3) and c-erbB-4 (HER4). Moderate to strong membrane-specific staining was recorded semiquantitatively (<10% vs ⩾10%=IHC stained tumour cells: ‘negative’ vs ‘positive’ staining). The medical records were reviewed for clinical variables. During the development of AIPC, intrapatient changes occurred in two opposite directions for each of the four EGFRs: negativity changed to positivity, and vice versa, statistically significant only for the increase of c-erbB-1 expression (P=0.001). The c-erbB-2 expression in the AIPC biopsy was associated with a significantly shorter survival from the time of the AIPC biopsy (P=0.029). Our results support ongoing therapeutic attempts of EGFR inhibition in subgroups of patients with prostate cancer. Further research is needed to understand the function of EGFRs in this malignancy.
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Affiliation(s)
- E Hernes
- Department of Clinical Cancer Research, The Norwegian Radium Hospital, Montebello, N-0310 Oslo, Norway.
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Rodnin NV, Tykhonkova IO, Kyyamova RG, Garifulin OM, Gout IT, Filonenko VV. Identification of tumor-associated antigens in human thyroid papillar carcinoma. ACTA ACUST UNITED AC 2003. [DOI: 10.7124/bc.000681] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- N. V. Rodnin
- Institute of Molecular Biology and Genetics, National Academy of Sciences of Ukraine
| | - I. O. Tykhonkova
- Institute of Molecular Biology and Genetics, National Academy of Sciences of Ukraine
| | - R. G. Kyyamova
- Institute of Molecular Biology and Genetics, National Academy of Sciences of Ukraine
| | - O. M. Garifulin
- Institute of Molecular Biology and Genetics, National Academy of Sciences of Ukraine
| | - I. T. Gout
- Institute of Molecular Biology and Genetics, National Academy of Sciences of Ukraine
- Ludwig Institute for Cancer Research
| | - V. V. Filonenko
- Institute of Molecular Biology and Genetics, National Academy of Sciences of Ukraine
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Zhang XQ, Kondrikov D, Yuan TC, Lin FF, Hansen J, Lin MF. Receptor protein tyrosine phosphatase alpha signaling is involved in androgen depletion-induced neuroendocrine differentiation of androgen-sensitive LNCaP human prostate cancer cells. Oncogene 2003; 22:6704-16. [PMID: 14555984 DOI: 10.1038/sj.onc.1206764] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The neuroendocrine (NE) cells represent the third cell population in the normal prostate. Results of several clinical studies strongly indicate that the NE cell population is greatly increased in prostate carcinomas during androgen ablation therapy that correlates with hormone-refractory growth and poor prognosis. However, the mechanism of NE cell enrichment in prostate carcinoma remains an enigma. We investigated the molecular mechanism by which androgen-sensitive C-33 LNCaP human prostate cancer cells become NE-like cells in an androgen-reduced environment, mimicking clinical phenomenon. In the androgen-depleted condition, androgen-sensitive C-33 LNCaP cells gradually acquired the NE-like morphology and expressed an increased level of neuron-specific enolase (NSE), a classical marker of neuronal cells. Several NE-like subclone cells were established. Biochemical characterizations of these subclone cells showed that receptor-type protein-tyrosine phosphatase alpha (RPTPalpha) is elevated and ERK is constitutively activated, several folds higher than that in parental cells. In androgen-depleted condition, PD98059, an MEK inhibitor, could efficiently block not only the activation of ERK, but also the acquisition of the NE-like morphology and the elevation of NSE in C-33 LNCaP cells. In RPTPalpha cDNA-transfected C-33 LNCaP cells, ERK was activated and NSE was elevated. In those cells in the presence of PD98059, the ERK activation and NSE elevation were abolished, following a dose-response fashion. Additionally, in constitutively active MEK mutant cDNA-transfected C-33 LNCaP cells, ERK was activated and NSE level was elevated, and cells obtained the NE-like phenotype. Our data collectively indicated that RPTPalpha signaling via ERK is involved in the NE transdifferentiation of androgen-sensitive C-33 LNCaP human prostate cancer cells in the androgen-depleted condition.
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Affiliation(s)
- Xiu-Qing Zhang
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, 984525 Nebraska Medical Center, Omaha, NE 68198-4525, USA
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