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Maes J, Gesquière S, De Spiegeleer A, Maes A, Van de Wiele C. Prostate-Specific Membrane Antigen Biology and Pathophysiology in Prostate Carcinoma, an Update: Potential Implications for Targeted Imaging and Therapy. Int J Mol Sci 2024; 25:9755. [PMID: 39273701 PMCID: PMC11396261 DOI: 10.3390/ijms25179755] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2024] [Revised: 08/28/2024] [Accepted: 09/04/2024] [Indexed: 09/15/2024] Open
Abstract
Prostate-specific membrane antigen (PSMA), a transmembrane glycoprotein, was shown to be expressed 100-1000 fold higher in prostate adenocarcinoma as compared to normal prostate epithelium. Given the enzymatic function of PSMA with the presence of an internalization triggering motif, various Glu-urea-Lys-based inhibitors have been developed and, amongst others, radiolabeled with positron emitters for targeted positron emission tomography imaging such as 68Ga-PSMA-HBED-CC Glu-urea-Lys(Ahx) as well as with beta and alpha-emitting radioisotopes for targeted therapy, e.g., 177Lu-PSMA-617. In this paper, we review and discuss the potential implications for targeted imaging and therapy of altered PSMA-glycosylation, of PSMA-driven activation of the P13K/Akt/mTOR, of the evolution over time and the relationship with androgen signaling and changes in DNA methylation of PSMA, and of androgen deprivation therapy (ADT) in prostate carcinoma.
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Affiliation(s)
| | - Simon Gesquière
- Department of Diagnostic Sciences, University Ghent, De Pintelaan 185, 9000 Ghent, Belgium
| | | | - Alex Maes
- AZ Groeninge, 8500 Kortrijk, Belgium
- Department of Morphology and Functional Imaging, University Leuven, 3000 Leuven, Belgium
| | - Christophe Van de Wiele
- AZ Groeninge, 8500 Kortrijk, Belgium
- Department of Diagnostic Sciences, University Ghent, De Pintelaan 185, 9000 Ghent, Belgium
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2
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Mackay S, Oduor IO, Burch TC, Troyer DA, Semmes OJ, Nyalwidhe JO. Prostate-specific membrane antigen (PSMA) glycoforms in prostate cancer patients seminal plasma. Prostate 2024; 84:479-490. [PMID: 38151791 DOI: 10.1002/pros.24666] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/11/2023] [Revised: 12/11/2023] [Accepted: 12/15/2023] [Indexed: 12/29/2023]
Abstract
INTRODUCTION Prostate-specific membrane antigen (PSMA) is a US Food and Drug Administration-approved theranostic target for prostate cancer (PCa). Although PSMA is known to be glycosylated, the composition and functional roles of its N-linked glycoforms have not been fully characterized. METHODS PSMA was isolated from pooled seminal plasma from low-risk grade Groups 1 and 2 PCa patients. Intact glycopeptides were analyzed by mass spectrometry to identify site-specific glycoforms. RESULTS We observed a rich distribution of PSMA glycoforms in seminal plasma from low and low-intermediate-risk PCa patients. Some interesting generalities can be drawn based on the predicted topology of PSMA on the plasma membrane. The glycoforms at ASN-459, ASN-476, and ASN-638 residues that are located at the basal domain facing the plasma membrane in cells, are predominantly high mannose glycans. ASN-76 which is located in the interdomain region adjacent to the apical domain of the protein shows a mixture of high mannose glycans and complex glycans, whereas ASN-121, ASN-195 and ASN-336 that are located and are exposed at the apical domain of the protein predominantly possess complex sialylated and fucosylated N-linked glycans. These highly accessible glycosites display the greatest diversity in isoforms across the patient samples. CONCLUSIONS Our study provides novel qualitative insights into PSMA glycoforms that are present in the seminal fluid of PCa patients. The presence of a rich diversity of glycoforms in seminal plasma provides untapped potential for glycoprotein biomarker discovery and as a clinical sample for noninvasive diagnostics of male urological disorders and diseases including PCa. Specifically, our glycomics approach will be critical in uncovering PSMA glycoforms with utility in staging and risk stratification of PCa.
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Affiliation(s)
- Stephen Mackay
- Leroy T. Canoles Jr. Cancer Research Center, Eastern Virginia Medical School, Norfolk, Virginia, USA
- Department of Microbiology and Molecular Cell Biology, Eastern Virginia Medical School, Norfolk, Virginia, USA
- Department of Neonatal-Perinatal Medicine, University of North Carolina, Chapel Hill, North Carolina, USA
| | - Ian O Oduor
- Leroy T. Canoles Jr. Cancer Research Center, Eastern Virginia Medical School, Norfolk, Virginia, USA
- Department of Neurology, Children's Hospital of the Kings Daughters, Norfolk, Virginia, USA
| | - Tanya C Burch
- Leroy T. Canoles Jr. Cancer Research Center, Eastern Virginia Medical School, Norfolk, Virginia, USA
- Department of Microbiology and Molecular Cell Biology, Eastern Virginia Medical School, Norfolk, Virginia, USA
| | - Dean A Troyer
- Leroy T. Canoles Jr. Cancer Research Center, Eastern Virginia Medical School, Norfolk, Virginia, USA
- Department of Microbiology and Molecular Cell Biology, Eastern Virginia Medical School, Norfolk, Virginia, USA
| | - Oliver J Semmes
- Leroy T. Canoles Jr. Cancer Research Center, Eastern Virginia Medical School, Norfolk, Virginia, USA
- Department of Microbiology and Molecular Cell Biology, Eastern Virginia Medical School, Norfolk, Virginia, USA
| | - Julius O Nyalwidhe
- Leroy T. Canoles Jr. Cancer Research Center, Eastern Virginia Medical School, Norfolk, Virginia, USA
- Department of Microbiology and Molecular Cell Biology, Eastern Virginia Medical School, Norfolk, Virginia, USA
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Mia MAR, Dey D, Sakib MR, Biswas MY, Prottay AAS, Paul N, Rimti FH, Abdullah Y, Biswas P, Iftehimul M, Paul P, Sarkar C, El-Nashar HAS, El-Shazly M, Islam MT. The efficacy of natural bioactive compounds against prostate cancer: Molecular targets and synergistic activities. Phytother Res 2023; 37:5724-5754. [PMID: 37786304 DOI: 10.1002/ptr.8017] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Revised: 08/17/2023] [Accepted: 09/05/2023] [Indexed: 10/04/2023]
Abstract
Globally, prostate cancer (PCa) is regarded as a challenging health issue, and the number of PCa patients continues to rise despite the availability of effective treatments in recent decades. The current therapy with chemotherapeutic drugs has been largely ineffective due to multidrug resistance and the conventional treatment has restricted drug accessibility to malignant tissues, necessitating a higher dosage resulting in increased cytotoxicity. Plant-derived bioactive compounds have recently attracted a great deal of attention in the field of PCa treatment due to their potent effects on several molecular targets and synergistic effects with anti-PCa drugs. This review emphasizes the molecular mechanism of phytochemicals on PCa cells, the synergistic effects of compound-drug interactions, and stem cell targeting for PCa treatment. Some potential compounds, such as curcumin, phenethyl-isothiocyanate, fisetin, baicalein, berberine, lutein, and many others, exert an anti-PCa effect via inhibiting proliferation, metastasis, cell cycle progression, and normal apoptosis pathways. In addition, multiple studies have demonstrated that the isolated natural compounds: d-limonene, paeonol, lanreotide, artesunate, and bicalutamide have potential synergistic effects. Further, a significant number of natural compounds effectively target PCa stem cells. However, further high-quality studies are needed to firmly establish the clinical efficacy of these phytochemicals against PCa.
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Affiliation(s)
- Md Abdur Rashid Mia
- Department of Biochemistry and Molecular Biology, University of Rajshahi, Rajshahi, Bangladesh
| | - Dipta Dey
- Department of Biochemistry and Molecular Biology, Bangabandhu Sheikh Mujibur Rahman Science and Technology University, Gopalgonj, Bangladesh
| | - Musfiqur Rahman Sakib
- Department of Pharmacy, Bangabandhu Sheikh Mujibur Rahman Science and Technology University, Gopalgonj, Bangladesh
| | - Md Yeaman Biswas
- Department of Genetic Engineering and Biotechnology, Jashore University of Science and Technology (JUST), Jashore, Bangladesh
| | - Abdullah Al Shamsh Prottay
- Department of Pharmacy, Bangabandhu Sheikh Mujibur Rahman Science and Technology University, Gopalgonj, Bangladesh
| | - Niloy Paul
- Department of Biochemistry and Molecular Biology, Bangabandhu Sheikh Mujibur Rahman Science and Technology University, Gopalgonj, Bangladesh
| | - Fahmida Hoque Rimti
- Bachelor of Medicine and Surgery, Chittagong Medical College, Chawkbazar, Bangladesh
| | - Yusuf Abdullah
- Department of Biochemistry and Molecular Biology, Bangabandhu Sheikh Mujibur Rahman Science and Technology University, Gopalgonj, Bangladesh
| | - Partha Biswas
- Department of Genetic Engineering and Biotechnology, Jashore University of Science and Technology (JUST), Jashore, Bangladesh
| | - Md Iftehimul
- Department of Fisheries and Marine Bioscience, Bangabandhu Sheikh Mujibur Rahman Science and Technology University, Gopalgonj, Bangladesh
| | - Priyanka Paul
- Department of Biochemistry and Molecular Biology, Bangabandhu Sheikh Mujibur Rahman Science and Technology University, Gopalgonj, Bangladesh
| | - Chandan Sarkar
- Department of Pharmacy, Bangabandhu Sheikh Mujibur Rahman Science and Technology University, Gopalgonj, Bangladesh
| | - Heba A S El-Nashar
- Department of Pharmacognosy, Faculty of Pharmacy, Ain Shams University, Cairo, Egypt
| | - Mohamed El-Shazly
- Department of Pharmacognosy, Faculty of Pharmacy, Ain Shams University, Cairo, Egypt
| | - Muhammad Torequl Islam
- Department of Pharmacy, Bangabandhu Sheikh Mujibur Rahman Science and Technology University, Gopalgonj, Bangladesh
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Eltit F, Robinson N, Yu PLI, Pandey M, Lozada J, Guo Y, Sharma M, Ozturan D, Ganier L, Belanger E, Lack NA, Perrin DM, Cox ME, Goldenberg SL. The "Ins and Outs" of Prostate Specific Membrane Antigen (PSMA) as Specific Target in Prostate Cancer Therapy. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2023; 1408:291-308. [PMID: 37093434 DOI: 10.1007/978-3-031-26163-3_16] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/25/2023]
Abstract
Prostate-specific membrane antigen (PSMA) is expressed in epithelial cells of the prostate gland and is strongly upregulated in prostatic adenocarcinoma, with elevated expression correlating with metastasis, progression, and androgen independence. Because of its specificity, PSMA is a major target of prostate cancer therapy; however, detectable levels of PSMA are also found in other tissues, especially in salivary glands and kidney, generating bystander damage of these tissues. Antibody target therapy has been used with relative success in reducing tumor growth and prostate specific antigen (PSA) levels. However, since antibodies are highly stable in plasma, they have prolonged time in circulation and accumulate in organs with an affinity for antibodies such as bone marrow. For that reason, a second generation of PSMA targeted therapeutic agents has been developed. Small molecules and minibodies have had promising clinical trial results, but concerns about their specificity had arisen with side effects due to accumulation in salivary glands and kidneys. Herein we study the specificity of small molecules and minibodies that are currently being clinically tested. We observed a high affinity of these molecules for PSMA in prostate, kidney and salivary gland, suggesting that their effect is not prostate specific. The search for specific prostate target agents must continue so as to optimally treat patients with prostate cancer, while minimizing deleterious effects in other PSMA expressing tissues.
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Affiliation(s)
- Felipe Eltit
- Department of Urologic Sciences, University of British Columbia, 2775 Laurel Street, Vancouver, BC, V5Z 1M9, Canada
- Vancouver Prostate Centre, Vancouver, Canada
| | - Nicole Robinson
- Department of Urologic Sciences, University of British Columbia, 2775 Laurel Street, Vancouver, BC, V5Z 1M9, Canada
- Vancouver Prostate Centre, Vancouver, Canada
| | - Pak Lok Ivan Yu
- Department of Urologic Sciences, University of British Columbia, 2775 Laurel Street, Vancouver, BC, V5Z 1M9, Canada
- Vancouver Prostate Centre, Vancouver, Canada
| | - Mitali Pandey
- Department of Urologic Sciences, University of British Columbia, 2775 Laurel Street, Vancouver, BC, V5Z 1M9, Canada
- Vancouver Prostate Centre, Vancouver, Canada
| | - Jerome Lozada
- Department of Chemistry, University of British Columbia, Vancouver, BC, Canada
| | - Yubin Guo
- Department of Urologic Sciences, University of British Columbia, 2775 Laurel Street, Vancouver, BC, V5Z 1M9, Canada
- Vancouver Prostate Centre, Vancouver, Canada
| | - Manju Sharma
- Department of Urologic Sciences, University of British Columbia, 2775 Laurel Street, Vancouver, BC, V5Z 1M9, Canada
- Vancouver Prostate Centre, Vancouver, Canada
| | - Dogancan Ozturan
- Department of Urologic Sciences, University of British Columbia, 2775 Laurel Street, Vancouver, BC, V5Z 1M9, Canada
- Vancouver Prostate Centre, Vancouver, Canada
| | - Laetitia Ganier
- Department of Urologic Sciences, University of British Columbia, 2775 Laurel Street, Vancouver, BC, V5Z 1M9, Canada
- Vancouver Prostate Centre, Vancouver, Canada
| | - Eric Belanger
- Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, Canada
| | - Nathan A Lack
- Vancouver Prostate Centre, Vancouver, Canada
- Koç University Research Center for Translational Medicine (KUTTAM), Istanbul, Türkiye
- Koç University School of Medicine, Istanbul, Türkiye
| | - David M Perrin
- Department of Chemistry, University of British Columbia, Vancouver, BC, Canada
| | - Michael E Cox
- Department of Urologic Sciences, University of British Columbia, 2775 Laurel Street, Vancouver, BC, V5Z 1M9, Canada
- Vancouver Prostate Centre, Vancouver, Canada
| | - S Larry Goldenberg
- Department of Urologic Sciences, University of British Columbia, 2775 Laurel Street, Vancouver, BC, V5Z 1M9, Canada.
- Vancouver Prostate Centre, Vancouver, Canada.
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Mackay S, Hitefield NL, Oduor IO, Roberts AB, Burch TC, Lance RS, Cunningham TD, Troyer DA, Semmes OJ, Nyalwidhe JO. Site-Specific Intact N-Linked Glycopeptide Characterization of Prostate-Specific Membrane Antigen from Metastatic Prostate Cancer Cells. ACS OMEGA 2022; 7:29714-29727. [PMID: 36061737 PMCID: PMC9435049 DOI: 10.1021/acsomega.2c02265] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Accepted: 08/04/2022] [Indexed: 06/15/2023]
Abstract
The composition of N-linked glycans that are conjugated to the prostate-specific membrane antigen (PSMA) and their functional significance in prostate cancer progression have not been fully characterized. PSMA was isolated from two metastatic prostate cancer cell lines, LNCaP and MDAPCa2b, which have different tissue tropism and localization. Isolated PSMA was trypsin-digested, and intact glycopeptides were subjected to LC-HCD-EThcD-MS/MS analysis on a Tribrid Orbitrap Fusion Lumos mass spectrometer. Differential qualitative and quantitative analysis of site-specific N-glycopeptides was performed using Byonic and Byologic software. Comparative quantitative analysis demonstrates that multiple glycopeptides at asparagine residues 51, 76, 121, 195, 336, 459, 476, and 638 were in significantly different abundance in the two cell lines (p < 0.05). Biochemical analysis using endoglycosidase treatment and lectin capture confirm the MS and site occupancy data. The data demonstrate the effectiveness of the strategy for comprehensive analysis of PSMA glycopeptides. This approach will form the basis of ongoing experiments to identify site-specific glycan changes in PSMA isolated from disease-stratified clinical samples to uncover targets that may be associated with disease progression and metastatic phenotypes.
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Affiliation(s)
- Stephen Mackay
- Leroy
T. Canoles Jr. Cancer Research Center, Eastern
Virginia Medical School, Norfolk, Virginia 23507, United States
- Department
of Microbiology and Molecular Cell Biology, Eastern Virginia Medical School, Norfolk, Virginia 23507, United States
- University
of North Carolina, Chapel Hill, North Carolina 27516, United States
| | - Naomi L. Hitefield
- Leroy
T. Canoles Jr. Cancer Research Center, Eastern
Virginia Medical School, Norfolk, Virginia 23507, United States
- Department
of Microbiology and Molecular Cell Biology, Eastern Virginia Medical School, Norfolk, Virginia 23507, United States
- University
of Georgia, Athens, Georgia 30602, United
States
| | - Ian O. Oduor
- Leroy
T. Canoles Jr. Cancer Research Center, Eastern
Virginia Medical School, Norfolk, Virginia 23507, United States
| | - Autumn B. Roberts
- Leroy
T. Canoles Jr. Cancer Research Center, Eastern
Virginia Medical School, Norfolk, Virginia 23507, United States
- Department
of Microbiology and Molecular Cell Biology, Eastern Virginia Medical School, Norfolk, Virginia 23507, United States
| | - Tanya C. Burch
- Leroy
T. Canoles Jr. Cancer Research Center, Eastern
Virginia Medical School, Norfolk, Virginia 23507, United States
- Department
of Microbiology and Molecular Cell Biology, Eastern Virginia Medical School, Norfolk, Virginia 23507, United States
| | - Raymond S. Lance
- Leroy
T. Canoles Jr. Cancer Research Center, Eastern
Virginia Medical School, Norfolk, Virginia 23507, United States
- Spokane
Urology, Spokane, Washington 99202, United States
| | - Tina D. Cunningham
- School of
Health Professions, Eastern Virginia Medical
School, Norfolk, Virginia 23507, United States
| | - Dean A. Troyer
- Leroy
T. Canoles Jr. Cancer Research Center, Eastern
Virginia Medical School, Norfolk, Virginia 23507, United States
- Department
of Microbiology and Molecular Cell Biology, Eastern Virginia Medical School, Norfolk, Virginia 23507, United States
| | - Oliver J. Semmes
- Leroy
T. Canoles Jr. Cancer Research Center, Eastern
Virginia Medical School, Norfolk, Virginia 23507, United States
- Department
of Microbiology and Molecular Cell Biology, Eastern Virginia Medical School, Norfolk, Virginia 23507, United States
| | - Julius O. Nyalwidhe
- Leroy
T. Canoles Jr. Cancer Research Center, Eastern
Virginia Medical School, Norfolk, Virginia 23507, United States
- Department
of Microbiology and Molecular Cell Biology, Eastern Virginia Medical School, Norfolk, Virginia 23507, United States
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Yuan W, Liu B, Sanda M, Wei R, Benicky J, Novakova Z, Barinka C, Goldman R. Glycoforms of human prostate-specific membrane antigen (PSMA) in human cells and prostate tissue. Prostate 2022; 82:132-144. [PMID: 34662441 PMCID: PMC9646948 DOI: 10.1002/pros.24254] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Accepted: 09/27/2021] [Indexed: 01/03/2023]
Abstract
INTRODUCTION N-glycosylation is a ubiquitous and variable posttranslational modification that regulates physiological functions of secretory and membrane-associated proteins and the dysregulation of glycosylation pathways is often associated with cancer growth and metastasis. Prostate-specific membrane antigen (PSMA) is an established biomarker for prostate cancer imaging and therapy. METHODS Mass spectrometry was used to analyze the distribution of the site-specific glycoforms of PSMA in insect, human embryonic kidney, and prostate cancer cells, and in prostate tissue upon immunoaffinity enrichment. RESULTS While recombinant PSMA expressed in insect cells was decorated mainly by paucimannose and high mannose glycans, complex, hybrid, and high mannose glycans were detected in samples from human cells and tissue. We noted an interesting spatial distribution of the glycoforms on the PSMA surface-high mannose glycans were the dominant glycoforms at the N459, N476, and N638 sequons facing the plasma membrane, while the N121, N195, and N336 sites, located at the exposed apical PSMA domain, carried primarily complex glycans. The presence of high mannose glycoforms at the former sequons likely results from the limited access of enzymes of the glycosynthetic pathway required for the synthesis of the complex structures. In line with the limited accessibility of membrane-proximal sites, no glycosylation was observed at the N51 site positioned closest to the membrane. CONCLUSIONS Our study presents initial descriptive analysis of the glycoforms of PSMA observed in cell lines and in prostate tissue. It will hopefully stimulate further research into PSMA glycoforms in the context of tumor staging, noninvasive detection of prostate tumors, and the impact of glycoforms on physicochemical and enzymatic characteristics of PSMA in a tissue-specific manner.
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Affiliation(s)
- Wei Yuan
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University, Washington DC, USA
- Clinical and Translational Glycoscience Research Center, Georgetown University Medical Center, Georgetown University, Washington DC, USA
| | - Baoqin Liu
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University, Washington DC, USA
| | - Miloslav Sanda
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University, Washington DC, USA
- Clinical and Translational Glycoscience Research Center, Georgetown University Medical Center, Georgetown University, Washington DC, USA
| | - Renhuizi Wei
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University, Washington DC, USA
- Clinical and Translational Glycoscience Research Center, Georgetown University Medical Center, Georgetown University, Washington DC, USA
| | - Julius Benicky
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University, Washington DC, USA
- Clinical and Translational Glycoscience Research Center, Georgetown University Medical Center, Georgetown University, Washington DC, USA
| | - Zora Novakova
- Laboratory of Structural Biology, Institute of Biotechnology of the Czech Academy of Sciences, BIOCEV, Vestec, Czech Republic
| | - Cyril Barinka
- Laboratory of Structural Biology, Institute of Biotechnology of the Czech Academy of Sciences, BIOCEV, Vestec, Czech Republic
| | - Radoslav Goldman
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University, Washington DC, USA
- Clinical and Translational Glycoscience Research Center, Georgetown University Medical Center, Georgetown University, Washington DC, USA
- Department of Biochemistry and Molecular & Cellular Biology, Georgetown University, Washington DC, USA
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Kranzbühler B, Sousa R, Prause L, Burger IA, Rupp NJ, Sulser T, Salemi S, Eberli D. Impact of short-term Dutasteride treatment on prostate-specific membrane antigen expression in a mouse xenograft model. Cancer Rep (Hoboken) 2021; 4:e1418. [PMID: 34008909 PMCID: PMC8714546 DOI: 10.1002/cnr2.1418] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2020] [Revised: 03/29/2021] [Accepted: 04/19/2021] [Indexed: 11/30/2022] Open
Abstract
Background Dutasteride has been shown to increase expression of the prostate‐specific membrane antigen (PSMA) in prostate cancer cells in previous in vitro studies. This 5‐alpha‐reductase inhibitor is commonly used for the treatment of symptomatic benign prostatic enlargement. The modulation of PSMA expression might affect PSMA‐based prostate cancer imaging and therapy. Aim The purpose of this work was to further analyze concentration‐dependent effects of Dutasteride on PSMA expression in a mouse xenograft model. Methods and results Four groups of mice bearing LNCaP xenografts were treated for 14 days with daily intraperitoneal injections of either vehicle control or different concentrations of Dutasteride (0.1, 1, 10 mg/kg). Total expression of PSMA, androgen receptor (AR), and caspase‐3 protein was analyzed using immunoblotting (WES). In addition, PSMA, cleaved caspase‐3 and Ki‐67 expression was assessed and quantified by immunohistochemistry. Tumor size was measured by caliper on day 7 and 14, tumor weight was assessed following tissue harvesting. The mean PSMA protein expression in mice increased significantly after treatment with 1 mg/kg (10‐fold) or 10 mg/kg (sixfold) of Dutasteride compared to vehicle control. The mean fluorescence intensity significantly increased by daily injections of 0.1 mg/kg Dutasteride (1.6‐fold) as well as 1 and 10 mg/kg Dutasteride (twofold). While the reduction in tumor volume following treatment with high concentrations of 10 mg/kg Dutasteride was nonsignificant, no changes in AR, caspase‐3, cleaved caspase‐3, and Ki‐67 expression were observed. Conclusion Short‐term Dutasteride treatments with concentrations of 1 and 10 mg/kg significantly increase the total PSMA protein expression in a mouse LNCaP xenograft model. PSMA fluorescence intensity increases significantly even using lower daily concentrations of 0.1 mg/kg Dutasteride. Further investigations are needed to elucidate the impact of Dutasteride treatment on PSMA expression in patients.
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Affiliation(s)
- Benedikt Kranzbühler
- Department of Urology, University Hospital Zürich, University of Zürich, Laboratory for Urologic Oncology and Stem Cell Therapy, Zürich, Switzerland
| | - Rosa Sousa
- Department of Urology, University Hospital Zürich, University of Zürich, Laboratory for Urologic Oncology and Stem Cell Therapy, Zürich, Switzerland
| | - Lukas Prause
- Department of Urology, University Hospital Zürich, University of Zürich, Laboratory for Urologic Oncology and Stem Cell Therapy, Zürich, Switzerland
| | - Irene A Burger
- Department of Nuclear Medicine, University Hospital of Zürich, University of Zürich, Zürich, Switzerland.,Department of Nuclear Medicine, Kantonsspital Baden, Baden, Switzerland
| | - Niels J Rupp
- Department of Pathology and Molecular Pathology, University Hospital of Zürich, University of Zürich, Zürich, Switzerland
| | - Tullio Sulser
- Department of Urology, University Hospital Zürich, University of Zürich, Laboratory for Urologic Oncology and Stem Cell Therapy, Zürich, Switzerland
| | - Souzan Salemi
- Department of Urology, University Hospital Zürich, University of Zürich, Laboratory for Urologic Oncology and Stem Cell Therapy, Zürich, Switzerland
| | - Daniel Eberli
- Department of Urology, University Hospital Zürich, University of Zürich, Laboratory for Urologic Oncology and Stem Cell Therapy, Zürich, Switzerland
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Nikfarjam Z, Bavi O, Amini SK. Potential effective inhibitory compounds against Prostate Specific Membrane Antigen (PSMA): A molecular docking and molecular dynamics study. Arch Biochem Biophys 2021; 699:108747. [PMID: 33422503 DOI: 10.1016/j.abb.2020.108747] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Revised: 12/16/2020] [Accepted: 12/27/2020] [Indexed: 02/07/2023]
Abstract
One of the most prevalent cancers in men is prostate cancer and could be managed with immunotoxins or antibody treatment. Because of the substantial rise of the Prostate-Specific Antigen and the Prostate-Specific Membrane Antigen (PSMA), cancer vaccination should be rendered with these antigens. Through pharmacodynamic experiments in a library of natural compounds from ZINC database, the current research sought to identify compounds that could suppress PSMA protein. To test the most productive compounds for further research, the Library has been scanned with Pharmacophore and ADMET analysis followed by molecular docking methods in the first phase. After selecting 15 ligands with the best pose related to docking results, to evaluate the stability of the ligand-protein bounds of the compounds, a molecular dynamics simulation considering the effect of the presence of zinc ions on the protein structure was performed. The measurement of ligand binding modes and free energy has shown that four compounds, including Z10, Z06, Z01, and Z03, have formed critical interactions with the active site's residues. Besides, multiple approaches were employed to determine their inhibition rating and describe the variables that facilitate the attachment of ligands to the protein active site. The results are obtained from the MMPBSA/GBSA analysis of four selected small molecules (Z10, Z06, Z01, and Z03), which are very close to the IC50 value of reference ligand (DCIBzl); they are -13.85 kcal/mol, -12.58 kcal/mol, -10.71 kcal/mol and -9.39 kcal/mol respectively. Finally, we evaluate the results obtained from selected ligands using hydrogen bond and decomposition analyzes. We have examined the effective interactions between ligands and S1/S1'pockets in protein. Our computational results illustrate the design of more efficient inhibitors of PSMA.
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Affiliation(s)
- Zahra Nikfarjam
- Department of Physical & Computational Chemistry, Chemistry and Chemical Engineering Research Center of Iran, Tehran, 1496813151, Iran
| | - Omid Bavi
- Department of Mechanical and Aerospace Engineering, Shiraz University of Technology, Shiraz, 71557-13876, Iran.
| | - Saeed K Amini
- Department of Physical & Computational Chemistry, Chemistry and Chemical Engineering Research Center of Iran, Tehran, 1496813151, Iran.
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Peng SL, Lai CH, Chu PY, Hsieh JT, Tseng YC, Chiu SC, Lin YH. Nanotheranostics With the Combination of Improved Targeting, Therapeutic Effects, and Molecular Imaging. Front Bioeng Biotechnol 2020; 8:570490. [PMID: 33042972 PMCID: PMC7523243 DOI: 10.3389/fbioe.2020.570490] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Accepted: 08/27/2020] [Indexed: 12/27/2022] Open
Abstract
There is an increasing interest in the design of targeted carrier systems with combined therapeutic and diagnostic modalities. Therapeutic modalities targeting tumors with single ligand-based targeting nanocarriers are insufficient for proficient delivery and for targeting two different surface receptors that are overexpressed in cancer cells. Here, we evaluated an activated nanoparticle delivery system comprising fucoidan/hyaluronic acid to improve therapeutic efficacy. The system comprised polyethylene glycol-gelatin-encapsulated epigallocatechin gallate (EGCG), poly (D,L-lactide-co-glycolide; PLGA), and stable iron oxide nanoparticles (IOs). The latter enables targeting of prostate cancers in their molecular images. We demonstrate the transfer of nanoparticles and their entry into prostate cancer cells through ligand-specific recognition. This system may prove the benefits of drug delivery that enhances the inhibition of cell growth through apoptosis induction. Moreover, the improved targeting of nanotheranostics significantly suppressed orthotopic prostate tumor growth and more accurately targeted tumors compared with systemic combination therapy. In the presence of nanoparticles with iron oxides, the hypointensity of the prostate tumor was visualized on a T2-weignted magnetic resonance image. The diagnostic ability of this system was demonstrated by accumulating fluorescent nanoparticles in the prostate tumor from the in vivo imaging system, computed tomography. It is suggested that theranostic nanoparticles combined with a molecular imaging system can be a promising cancer therapy in the future.
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Affiliation(s)
- Shin-Lei Peng
- Department of Biomedical Imaging and Radiological Science, China Medical University, Taichung, Taiwan
| | - Chih-Ho Lai
- Department of Microbiology and Immunology, Molecular Infectious Disease Research Center, Chang Gung University, Chang Gung Memorial Hospital, Taoyuan, Taiwan
| | - Pei-Yi Chu
- Faculty of Pharmacy, National Yang-Ming University, Taipei, Taiwan
| | - Jer-Tsong Hsieh
- Department of Urology, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - Yen-Chun Tseng
- Department of Biological Science and Technology, China Medical University, Taichung, Taiwan
| | - Shao-Chieh Chiu
- Center for Advanced Molecular Imaging and Translation, Chang Gung Memorial Hospital, Taoyuan, Taiwan
| | - Yu-Hsin Lin
- Faculty of Pharmacy, National Yang-Ming University, Taipei, Taiwan
- Department of Medical Research, China Medical University Hospital, China Medical University, Taichung, Taiwan
- Institute of Biopharmaceutical Science, Department and Institute of Pharmacology, Center for Advanced Pharmaceutics and Drug Delivery Research, National Yang-Ming University, Taipei, Taiwan
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10
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O'Keefe DS, Bacich DJ, Huang SS, Heston WDW. A Perspective on the Evolving Story of PSMA Biology, PSMA-Based Imaging, and Endoradiotherapeutic Strategies. J Nucl Med 2018; 59:1007-1013. [PMID: 29674422 DOI: 10.2967/jnumed.117.203877] [Citation(s) in RCA: 111] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2018] [Accepted: 04/03/2018] [Indexed: 12/16/2022] Open
Abstract
In this review, we cover the evolution of knowledge on the biology of prostate-specific membrane antigen (PSMA) and its translation to therapy. The usual key to discovery is a realistic model for experimentation and for testing a hypothesis. A realistic model is especially needed in the case of the human prostate, which differs significantly from the prostate of species often used as research models. We will emphasize the genetic characterization of PSMA, the nature of the PSMA protein, and its role as a carboxypeptidase, with differing important substrates and products in different tissues. We give special prominence to the importance of PSMA as a target for imaging and therapy in prostate cancer and its underdeveloped role for imaging and targeting the neovasculature of tumors other than prostate cancer. Lastly, we bring attention to its importance in other nonprostatic tissues.
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Affiliation(s)
- Denise S O'Keefe
- Department of Urology, University of Texas Health Science Center at San Antonio, San Antonio, Texas
| | - Dean J Bacich
- Department of Urology, University of Texas Health Science Center at San Antonio, San Antonio, Texas
| | - Steve S Huang
- Imaging Institute and Cancer Biology Department, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio
| | - Warren D W Heston
- Department of Cancer Biology, Lerner Research Institute and Glickman Urologic Institute, Cleveland Clinic, Cleveland, Ohio
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11
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Kaittanis C, Andreou C, Hieronymus H, Mao N, Foss CA, Eiber M, Weirich G, Panchal P, Gopalan A, Zurita J, Achilefu S, Chiosis G, Ponomarev V, Schwaiger M, Carver BS, Pomper MG, Grimm J. Prostate-specific membrane antigen cleavage of vitamin B9 stimulates oncogenic signaling through metabotropic glutamate receptors. J Exp Med 2017; 215:159-175. [PMID: 29141866 PMCID: PMC5748857 DOI: 10.1084/jem.20171052] [Citation(s) in RCA: 121] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Revised: 08/17/2017] [Accepted: 10/04/2017] [Indexed: 12/14/2022] Open
Abstract
Kaittanis et al. show that the processing of glutamated folates by prostate-specific membrane antigen induces the activation of metabotropic glutamate receptors and initiation of PI3K–Akt signaling in prostate cancer. Prostate-specific membrane antigen (PSMA) or folate hydrolase 1 (FOLH1) is highly expressed on prostate cancer. Its expression correlates inversely with survival and increases with tumor grade. However, the biological role of PSMA has not been explored, and its role in prostate cancer remained elusive. Filling this gap, we demonstrate that in prostate cancer, PSMA initiates signaling upstream of PI3K through G protein–coupled receptors, specifically via the metabotropic glutamate receptor (mGluR). PSMA’s carboxypeptidase activity releases glutamate from vitamin B9 and other glutamated substrates, which activate mGluR I. Activated mGluR I subsequently induces activation of phosphoinositide 3-kinase (PI3K) through phosphorylation of p110β independent of PTEN loss. The p110β isoform of PI3K plays a particularly important role in the pathogenesis of prostate cancer, but the origin of its activation was so far unknown. PSMA expression correlated with PI3K–Akt signaling in cells, animal models, and patients. We interrogated the activity of the PSMA–PI3K axis through positron emission tomography and magnetic resonance imaging. Inhibition of PSMA in preclinical models inhibited PI3K signaling and promoted tumor regression. Our data present a novel oncogenic signaling role of PSMA that can be exploited for therapy and interrogated with imaging.
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Affiliation(s)
- Charalambos Kaittanis
- Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, New York, NY.,Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, Boston, MA
| | - Chrysafis Andreou
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, NY
| | - Haley Hieronymus
- Human Oncology and Pathogenesis Program, Memorial Sloan Kettering Cancer Center, New York, NY
| | - Ninghui Mao
- Human Oncology and Pathogenesis Program, Memorial Sloan Kettering Cancer Center, New York, NY
| | - Catherine A Foss
- Russell H. Morgan Department of Radiology and Radiological Sciences, Johns Hopkins University, Baltimore, MD
| | - Matthias Eiber
- Department of Nuclear Medicine, Technische Universität München, Klinikum rechts der Isar, Munich, Germany
| | - Gregor Weirich
- Department of Pathology, Technische Universität München, Klinikum rechts der Isar, Munich, Germany
| | - Palak Panchal
- Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, New York, NY
| | - Anuradha Gopalan
- Genitourinary Division, Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, NY
| | - Juan Zurita
- Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, New York, NY
| | - Samuel Achilefu
- Department of Radiology, Washington University School of Medicine, St. Louis, MO
| | - Gabriela Chiosis
- Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, New York, NY
| | - Vladimir Ponomarev
- Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, New York, NY
| | - Markus Schwaiger
- Department of Nuclear Medicine, Technische Universität München, Klinikum rechts der Isar, Munich, Germany
| | - Brett S Carver
- Human Oncology and Pathogenesis Program, Memorial Sloan Kettering Cancer Center, New York, NY
| | - Martin G Pomper
- Russell H. Morgan Department of Radiology and Radiological Sciences, Johns Hopkins University, Baltimore, MD
| | - Jan Grimm
- Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, New York, NY .,Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, NY.,Department of Pharmacology, Weill Cornell Medical College, New York, NY.,Department of Radiology, Weill Cornell Medical College, New York, NY
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12
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Kratochwil C, Giesel FL, Leotta K, Eder M, Hoppe-Tich T, Youssoufian H, Kopka K, Babich JW, Haberkorn U. PMPA for Nephroprotection in PSMA-Targeted Radionuclide Therapy of Prostate Cancer. J Nucl Med 2015; 56:293-8. [DOI: 10.2967/jnumed.114.147181] [Citation(s) in RCA: 84] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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13
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Liu T, Wu LY, Fulton MD, Johnson JM, Berkman CE. Prolonged androgen deprivation leads to downregulation of androgen receptor and prostate-specific membrane antigen in prostate cancer cells. Int J Oncol 2012; 41:2087-92. [PMID: 23041906 PMCID: PMC3583693 DOI: 10.3892/ijo.2012.1649] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2012] [Accepted: 09/12/2012] [Indexed: 02/07/2023] Open
Abstract
Emergence of androgen-independent cancer cells during androgen deprivation therapy presents a significant challenge to successful treatment outcomes in prostate cancer. Elucidating the role of androgen deprivation in the transition from an androgen-dependent to an androgen-independent state may enable the development of more effective therapeutic strategies against prostate cancer. Herein, we describe an in vitro model for assessing the effects of continuous androgen-deprivation on prostate cancer cells (LNCaP) with respect to the expression of two prostate-specific markers: the androgen receptor (AR) and prostate-specific membrane antigen (PSMA). Compared with androgen-containing normal growth medium, androgen-deprived medium apparently induced the concomitant downregulation of AR and PSMA over time. Decreased protein levels were confirmed by fluorescence imaging, western blotting and enzymatic activity studies. In contrast to the current understanding of AR and PSMA in prostate cancer progression, our data demonstrated that androgen-deprivation induced a decrease in AR and PSMA levels in androgen-sensitive LNCaP cells, which may be associated with the development of more aggressive disease-state following androgen deprivation therapy.
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Affiliation(s)
- Tiancheng Liu
- Department of Chemistry, Washington State University, Pullman, WA 99164, USA
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14
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Foss CA, Mease RC, Cho SY, Kim HJ, Pomper MG. GCPII imaging and cancer. Curr Med Chem 2012; 19:1346-59. [PMID: 22304713 DOI: 10.2174/092986712799462612] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2011] [Revised: 12/26/2011] [Accepted: 12/27/2011] [Indexed: 12/11/2022]
Abstract
Glutamate carboxypeptidase II (GCPII) in the central nervous system is referred to as the prostate-specific membrane antigen (PSMA) in the periphery. PSMA serves as a target for imaging and treatment of prostate cancer and because of its expression in solid tumor neovasculature has the potential to be used in this regard for other malignancies as well. An overview of GCPII/PSMA in cancer, as well as a discussion of imaging and therapy of prostate cancer using a wide variety of PSMA-targeting agents is provided.
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Affiliation(s)
- C A Foss
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Medical School, Baltimore, MD 21231, USA
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15
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Bařinka C, Rojas C, Slusher B, Pomper M. Glutamate carboxypeptidase II in diagnosis and treatment of neurologic disorders and prostate cancer. Curr Med Chem 2012; 19:856-70. [PMID: 22214450 DOI: 10.2174/092986712799034888] [Citation(s) in RCA: 135] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2011] [Revised: 11/10/2011] [Accepted: 11/14/2011] [Indexed: 12/14/2022]
Abstract
Glutamate carboxypeptidase II (GCPII) is a membrane-bound binuclear zinc metallopeptidase with the highest expression levels found in the nervous and prostatic tissue. Throughout the nervous system, glia-bound GCPII is intimately involved in the neuron-neuron and neuron-glia signaling via the hydrolysis of N-acetylaspartylglutamate (NAAG), the most abundant mammalian peptidic neurotransmitter. The inhibition of the GCPII-controlled NAAG catabolism has been shown to attenuate neurotoxicity associated with enhanced glutamate transmission and GCPII-specific inhibitors demonstrate efficacy in multiple preclinical models including traumatic brain injury, stroke, neuropathic and inflammatory pain, amyotrophic lateral sclerosis, and schizophrenia. The second major area of pharmacological interventions targeting GCPII focuses on prostate carcinoma; GCPII expression levels are highly increased in androgen-independent and metastatic disease. Consequently, the enzyme serves as a potential target for imaging and therapy. This review offers a summary of GCPII structure, physiological functions in healthy tissues, and its association with various pathologies. The review also outlines the development of GCPII-specific small-molecule compounds and their use in preclinical and clinical settings.
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Affiliation(s)
- C Bařinka
- Institute of Biotechnology, Academy of Sciences of the Czech Republic, Videnska 1083, 14200 Praha 4, Czech Republic.
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16
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Wang X, Ma D, Olson WC, Heston WDW. In vitro and in vivo responses of advanced prostate tumors to PSMA ADC, an auristatin-conjugated antibody to prostate-specific membrane antigen. Mol Cancer Ther 2011; 10:1728-39. [PMID: 21750220 DOI: 10.1158/1535-7163.mct-11-0191] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Prostate-specific membrane antigen (PSMA) is a membrane protein that is overexpressed manifold in prostate cancer and provides an attractive target for therapy. PSMA ADC is an antibody-drug conjugate (ADC) that consists of a fully human anti-PSMA monoclonal antibody conjugated to monomethylauristatin E through a valine-citrulline linker. In this study, the antitumor activity of PSMA ADC was evaluated against a panel of prostate cancer cell lines in vitro and in a novel in vivo model of taxane-refractory human prostate cancer. In vitro cell killing was efficient for cells with abundant PSMA expression (>10(5) molecules/cell; IC(50) ≤ 0.022 nmol/L) and 1,000-fold less efficient for cells with undetectable PSMA (IC(50) > 30 nmol/L). Intermediate potency (IC(50) = 0.80 nmol/L) was observed for cells with approximately 10(4) molecules of PSMA per cell, indicating a threshold PSMA level for selective cell killing. Similar in vitro activity was observed against androgen-dependent and -independent cells that had abundant PSMA expression. In vitro activity of PSMA ADC was also dependent on internalization and proper N-glycosylation/folding of PSMA. In contrast, less potent and nonselective cytotoxic activity was observed for a control ADC, free monomethylauristatin E, and other microtubule inhibitors. PSMA ADC showed high in vivo activity in treating xenograft tumors that had progressed following an initial course of docetaxel therapy, including tumors that were large (>700 mm(3)) before treatment with PSMA ADC. This study defines determinants of antitumor activity of a novel ADC. The findings here support the clinical evaluation of this agent in advanced prostate cancer.
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Affiliation(s)
- Xinning Wang
- Department of Cancer Biology, Cleveland Clinic Foundation, Cleveland, Ohio, USA
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17
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Yin L, Rao P, Elson P, Wang J, Ittmann M, Heston WDW. Role of TMPRSS2-ERG gene fusion in negative regulation of PSMA expression. PLoS One 2011; 6:e21319. [PMID: 21731703 PMCID: PMC3123299 DOI: 10.1371/journal.pone.0021319] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2010] [Accepted: 05/28/2011] [Indexed: 11/19/2022] Open
Abstract
Prostate specific membrane antigen (PSMA) is overexpressed in prostatic adenocarcinoma (CaP), and its expression is negatively regulated by androgen stimulation. However, it is still unclear which factors are involved in this downregulation. TMPRSS2-ERG fusion is the most common known gene rearrangement in prostate carcinoma. Androgen stimulation can increase expression of the TMPRSS2-ERG fusion in fusion positive prostate cancer cells. The purpose of this investigation is to determine whether PSMA expression can be regulated by the TMPRSS2-ERG gene fusion. We employed two PSMA positive cell lines: VCaP cells, which harbor TMPRSS2-ERG fusion, and LNCaP cells, which lack the fusion. After 24 hours of androgen treatment, TMPRSS2-ERG mRNA level was increased in VCaP cells. PSMA mRNA level was dramatically decreased in VCaP cells, while it only has moderate change in LNCaP cells. Treatment with the androgen antagonist flutamide partially restored PSMA expression in androgen-treated VCaP cells. Knocking down ERG by siRNA in VCaP cells enhances PSMA expression both in the presence and absence of synthetic androgen R1881. Overexpressing TMPRSS2-ERG fusions in LNCaP cells downregulated PSMA both in the presence or absence of R1881, while overexpressing wild type ERG did not. Using PSMA-based luciferase reporter assays, we found TMPRSS2-ERG fusion can inhibit PSMA activity at the transcriptional level. Our data indicated that downregulation of PSMA in androgen-treated VCaP cells appears partially mediated by TMPRSS2-ERG gene fusion.
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Affiliation(s)
- Lihong Yin
- Department of Cancer Biology, Cleveland Clinic, Cleveland, Ohio, United States of America
| | - Pravin Rao
- Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, Ohio, United States of America
| | - Paul Elson
- Department of Quantitative Health Sciences, Cleveland Clinic, Cleveland, Ohio, United States of America
| | - Jianghua Wang
- Department of Pathology and Immunology, Baylor College of Medicine, and the Michael E. DeBakey Veterans Affairs Medical Center (VAMC), Houston, Texas, United States of America
| | - Michael Ittmann
- Department of Pathology and Immunology, Baylor College of Medicine, and the Michael E. DeBakey Veterans Affairs Medical Center (VAMC), Houston, Texas, United States of America
| | - Warren D. W. Heston
- Department of Cancer Biology, Cleveland Clinic, Cleveland, Ohio, United States of America
- Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, Ohio, United States of America
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18
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Meany DL, Hackler L, Zhang H, Chan DW. Tyramide signal amplification for antibody-overlay lectin microarray: a strategy to improve the sensitivity of targeted glycan profiling. J Proteome Res 2011; 10:1425-31. [PMID: 21133419 DOI: 10.1021/pr1010873] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Antibody-overlay lectin microarray (ALM) has been used for targeted glycan profiling to identify disease-related protein glycoforms. In this context, high sensitivity is desired because it allows for the identification of disease-related glycoforms that are often present at low concentrations. We describe a new tyramide signal amplification (TSA) for the antibody-overlay lectin microarray procedure for sensitive profiling of glycosylation patterns. We demonstrate that TSA increased the sensitivity of the microarray over 100 times for glycan profiling using the model protein prostate specific antigen (PSA). The glycan profile of PSA enriched from LNCAP cells, obtained at a subnanogram level with the aid of TSA, was consistent with the previous reports. We also established the glycan profile of prostate specific membrane antigen (PSMA) using the TSA and ALM. Thus, the TSA for antibody-overlay lectin microarray is a sensitive, rapid, comprehensive, and high-throughput method for targeted glycan profiling and can potentially be used for the identification of disease-related protein glycoforms.
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Affiliation(s)
- Danni L Meany
- Department of Pathology, Johns Hopkins University, Baltimore, Maryland 21231, USA
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19
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Mlcochová P, Barinka C, Tykvart J, Sácha P, Konvalinka J. Prostate-specific membrane antigen and its truncated form PSM'. Prostate 2009; 69:471-9. [PMID: 19107881 DOI: 10.1002/pros.20894] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
BACKGROUND Prostate specific membrane antigen (PSMA) is a type II transmembrane protein overexpressed in prostate cancer as well as in the neovasculature of several non-prostatic solid tumors. In addition to full-length PSMA, several splice variants exist in prostatic tissue. Notably, the N-terminally truncated PSMA variant, termed PSM', is prevalent in healthy prostate, and the ratio of PSMA/PSM' mRNA has been shown to correlate with cancer progression. The widely accepted hypothesis is that the PSM' protein is a translation product arising from the alternatively spliced PSM' mRNA. METHODS Differential ultracentrifugation, cell surface biotinylation, Western blotting, and enzyme activity measurement were used to study the origin and localization of the PSMA/PSM' variants in prostatic (LNCaP; lymph-node carcinoma of the prostate) and non-prostatic (HEK293) cell lines. These experiments were further complemented by analysis of the N-glycosylation patterns of the PSMA/PSM' proteins and by site-directed mutagenesis. RESULTS We identified PSM' protein expression in both the LNCaP cell line and a non-cancerous HEK293 human cell line transfected with a plasmid encoding full-length PSMA. Differential centrifugation revealed that PSM' is localized predominantly to the cytosol of both these cell lines and is proteolytically active. Furthermore, the PSM' protein is N-glycosylated by a mixture of high-mannose and complex type oligosaccharides and therefore trafficked beyond the cis-Golgi compartment. CONCLUSIONS Our data suggest that the PSM' protein is likely not generated by alternative splicing of the PSMA gene but by different mechanism, probably via an endoproteolytic cleavage of the full-length PSMA.
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Affiliation(s)
- Petra Mlcochová
- Gilead Sciences and IOCB Research Centre, Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Prague, Czech Republic
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20
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Tsukamoto T, Wozniak KM, Slusher BS. Progress in the discovery and development of glutamate carboxypeptidase II inhibitors. Drug Discov Today 2007; 12:767-76. [PMID: 17826690 DOI: 10.1016/j.drudis.2007.07.010] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
During the past 10 years, substantial progress has been made in the discovery and development of small molecule glutamate carboxypeptidase II (GCP II) inhibitors. These inhibitors have provided the necessary tools to investigate the physiological role of GCP II as well as the potential therapeutic benefits of its inhibition in neurological disorders of glutamatergic dysregulation. This review article details key GCP II inhibitors discovered in the last decade and important findings from preclinical and clinical studies.
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21
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Hlouchová K, Barinka C, Klusák V, Sácha P, Mlcochová P, Majer P, Rulísek L, Konvalinka J. Biochemical characterization of human glutamate carboxypeptidase III. J Neurochem 2007; 101:682-96. [PMID: 17241121 DOI: 10.1111/j.1471-4159.2006.04341.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Human glutamate carboxypeptidase II (GCPII) is a transmembrane metallopeptidase found mainly in the brain, small intestine, and prostate. In the brain, it cleaves N-acetyl-L-aspartyl-glutamate, liberating free glutamate. Inhibition of GCPII has been shown to be neuroprotective in models of stroke and other neurodegenerations. In prostate, it is known as prostate-specific membrane antigen, a cancer marker. Recently, human glutamate carboxypeptidase III (GCPIII), a GCPII homolog with 67% amino acid identity, was cloned. While GCPII is recognized as an important pharmaceutical target, no biochemical study of human GCPIII is available at present. Here, we report the cloning, expression, and characterization of recombinant human GCPIII. We show that GCPIII lacks dipeptidylpeptidase IV-like activity, its activity is dependent on N-glycosylation, and it is effectively inhibited by several known inhibitors of GCPII. In comparison to GCPII, GCPIII has lower N-acetyl-L-aspartyl-glutamate-hydrolyzing activity, different pH and salt concentration dependence, and distinct substrate specificity, indicating that these homologs might play different biological roles. Based on a molecular model, we provide interpretation of the distinct substrate specificity of both enzymes, and examine the amino acid residues responsible for the differences by site-directed mutagenesis. These results may help to design potent and selective inhibitors of both enzymes.
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Affiliation(s)
- Klára Hlouchová
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Prague, Czech Republic
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22
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Sácha P, Zámecník J, Barinka C, Hlouchová K, Vícha A, Mlcochová P, Hilgert I, Eckschlager T, Konvalinka J. Expression of glutamate carboxypeptidase II in human brain. Neuroscience 2006; 144:1361-72. [PMID: 17150306 DOI: 10.1016/j.neuroscience.2006.10.022] [Citation(s) in RCA: 92] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2006] [Accepted: 10/07/2006] [Indexed: 11/26/2022]
Abstract
Glutamate carboxypeptidase II (GCPII) is a transmembrane glycoprotein expressed in various tissues. When expressed in the brain it cleaves the neurotransmitter N-acetylaspartylglutamate (NAAG), yielding free glutamate. In jejunum it hydrolyzes folylpoly-gamma-glutamate, thus facilitating folate absorption. The prostate form of GCPII, known as prostate specific membrane antigen (PSMA), is an established cancer marker. The NAAG-hydrolyzing activity of GCPII has been implicated in a number of pathological conditions in which glutamate is neurotoxic (e.g. amyotrophic lateral sclerosis, Huntington's disease, Alzheimer's disease, epilepsy, schizophrenia, and stroke). Inhibition of GCPII was shown to be neuroprotective in tissue culture and in animal models. GCPII is therefore an interesting putative therapeutic target. However, only very limited and controversial data on the expression and localization of GCPII in human brain are available. Therefore, we set out to analyze the activity and expression of GCPII in various compartments of the human brain using a radiolabeled substrate of the enzyme and the novel monoclonal antibody GCP-04, which recognizes an epitope on the extracellular portion of the enzyme and is more sensitive to GCPII than to the homologous GCPIII. We show that this antibody is more sensitive in immunoblots than the widely used antibody 7E11. By Western blot, we show that there are approximately 50-300 ng of GCPII/mg of total protein in human brain, depending on the specific area. Immunohistochemical analysis revealed that astrocytes specifically express GCPII in all parts of the brain. GCPII is enzymatically active and the level of activity follows the expression pattern. Using pure recombinant GCPII and homologous GCPIII, we conclude that GCPII is responsible for the majority of overall NAAG-hydrolyzing activity in the human brain.
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Affiliation(s)
- P Sácha
- Department of Biochemistry, Institute of Organic Chemistry and Biochemistry, Academy of Science of the Czech Republic, Flemingovo n.2, Prague 6, 16610 Czech Republic
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Yao V, Bacich DJ. Prostate specific membrane antigen (PSMA) expression gives prostate cancer cells a growth advantage in a physiologically relevant folate environment in vitro. Prostate 2006; 66:867-75. [PMID: 16496414 DOI: 10.1002/pros.20361] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
BACKGROUND Prostate specific membrane antigen (PSMA) expression is correlated with stage and grade of prostate cancer suggesting that it confers a growth advantage. We studied if PSMA folate hydrolase activity provides cells a growth advantage in a low folate (LF) micro-environment by hydrolyzing extracellular poly-gamma-glutamated folate to a form that cells can import. METHODS Proliferation of LNCaP and DU-145 cells was assessed in media containing low (LF), physiological (PF), or high (HF) folate with or without penta-gamma-glutamated folate and a PSMA specific folate hydrolase inhibitor, 2-(phosphonomethyl)-pentanedioic acid (2-PMPA). RESULTS LNCaP cells, which express PSMA, and DU-145 cells, which do not, displayed decreased proliferation when grown in LF or PF compared to HF media. This reduction in proliferation was eliminated in LNCaP cells when penta-gamma-glutamated folate was added to the media. In the presence of penta-gamma-glutamated folic acid DU-145 cells displayed increased growth but this was still significantly lower than growth in HF medium. Addition of 2-PMPA attenuated the increased growth seen in LNCaP cells but had no effect on DU-145 cell growth. CONCLUSIONS The folate hydrolase activity of PSMA may provide a growth advantage in LF and PF environments.
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Affiliation(s)
- Veronica Yao
- Department of Urology, University of Pittsburgh, Pittsburgh, Pennsylvania 15232, USA
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Mesters JR, Barinka C, Li W, Tsukamoto T, Majer P, Slusher BS, Konvalinka J, Hilgenfeld R. Structure of glutamate carboxypeptidase II, a drug target in neuronal damage and prostate cancer. EMBO J 2006; 25:1375-84. [PMID: 16467855 PMCID: PMC1422165 DOI: 10.1038/sj.emboj.7600969] [Citation(s) in RCA: 193] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2005] [Accepted: 12/23/2005] [Indexed: 11/09/2022] Open
Abstract
Membrane-bound glutamate carboxypeptidase II (GCPII) is a zinc metalloenzyme that catalyzes the hydrolysis of the neurotransmitter N-acetyl-L-aspartyl-L-glutamate (NAAG) to N-acetyl-L-aspartate and L-glutamate (which is itself a neurotransmitter). Potent and selective GCPII inhibitors have been shown to decrease brain glutamate and provide neuroprotection in preclinical models of stroke, amyotrophic lateral sclerosis, and neuropathic pain. Here, we report crystal structures of the extracellular part of GCPII in complex with both potent and weak inhibitors and with glutamate, the product of the enzyme's hydrolysis reaction, at 2.0, 2.4, and 2.2 A resolution, respectively. GCPII folds into three domains: protease-like, apical, and C-terminal. All three participate in substrate binding, with two of them directly involved in C-terminal glutamate recognition. One of the carbohydrate moieties of the enzyme is essential for homodimer formation of GCPII. The three-dimensional structures presented here reveal an induced-fit substrate-binding mode of this key enzyme and provide essential information for the design of GCPII inhibitors useful in the treatment of neuronal diseases and prostate cancer.
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Affiliation(s)
- Jeroen R Mesters
- Institute of Biochemistry, Center for Structural and Cell Biology in Medicine, University of Lübeck, Lübeck, Germany
| | - Cyril Barinka
- Institute of Organic Chemistry and Biochemistry, Academy of Science of the Czech Republic, Prague, Czech Republic
| | - Weixing Li
- Guilford Pharmaceuticals Inc., Baltimore, MD, USA
| | | | - Pavel Majer
- Guilford Pharmaceuticals Inc., Baltimore, MD, USA
| | | | - Jan Konvalinka
- Institute of Organic Chemistry and Biochemistry, Academy of Science of the Czech Republic, Prague, Czech Republic
| | - Rolf Hilgenfeld
- Institute of Biochemistry, Center for Structural and Cell Biology in Medicine, University of Lübeck, Lübeck, Germany
- Institute of Biochemistry, Center for Structural and Cell Biology in Medicine (CSCM), University of Lübeck, Ratzeburger Allee 160, D-23538 Lübeck, Germany. Tel.: +49 451 500 4060; Fax: +49 451 500 4068; E-mail:
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Castelletti D, Fracasso G, Alfalah M, Cingarlini S, Colombatti M, Naim HY. Apical Transport and Folding of Prostate-specific Membrane Antigen Occurs Independent of Glycan Processing. J Biol Chem 2006; 281:3505-12. [PMID: 16221666 DOI: 10.1074/jbc.m509460200] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Prostate-specific membrane antigen (PSMA) is an integral cell-surface membrane glycoprotein that is overexpressed in prostate carcinomas rendering it an appropriate target for antibody-based therapeutic strategies. The biosynthesis of PSMA in transfected COS-1 cells reveals a slow conversion of mannose-rich to complex glycosylated PSMA compatible with slow transport kinetics from the endoplasmic reticulum to the Golgi. Importantly, mannose-rich PSMA persists as a trypsin-sensitive protein throughout its entire life cycle, and only Golgi-located PSMA glycoforms acquire trypsin resistance. This resistance, used here as a tool to examine correct folding, does not depend on the type of glycosylation, because different PSMA glycoforms generated in the presence of inhibitors of carbohydrate processing in the Golgi are also trypsin resistant. The conformational transition of PSMA to a correctly folded molecule is likely to occur in the Golgi and does not implicate ER molecular chaperones, such as BiP. We show here that PSMA is not only heavily N-but also O-glycosylated. The question arising is whether glycans, which do not play a role in folding of PSMA, are implicated in its transport to the cell surface. Neither the cell-surface expression of PSMA nor its efficient apical sorting in polarized Madin-Darby canine kidney cells are influenced by modulators of N- and O-glycosylation. The acquisition of folding determinants in the Golgi, therefore, is an essential prerequisite for protein trafficking and sorting of PSMA and suggests that altered or aberrant glycosylation often occurring during tumorigenesis has no regulatory effect on the cell-surface expression of PSMA.
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Affiliation(s)
- Deborah Castelletti
- Department of Physiological Chemistry, University of Veterinary Medicine Hannover, Bünteweg 17, D-30559 Hannover, Germany
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Rajasekaran AK, Anilkumar G, Christiansen JJ. Is prostate-specific membrane antigen a multifunctional protein? Am J Physiol Cell Physiol 2005; 288:C975-81. [PMID: 15840561 DOI: 10.1152/ajpcell.00506.2004] [Citation(s) in RCA: 156] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Prostate-specific membrane antigen (PSMA) is a metallopeptidase expressed predominantly in prostate cancer (PCa) cells. PSMA is considered a biomarker for PCa and is under intense investigation for use as an imaging and therapeutic target. Although the clinical utility of PSMA in the detection and treatment of PCa is evident and is being pursued, very little is known about its basic biological function in PCa cells. The purpose of this review is to highlight the possibility that PSMA might be a multifunctional protein. We suggest that PSMA may function as a receptor internalizing a putative ligand, an enzyme playing a role in nutrient uptake, and a peptidase involved in signal transduction in prostate epithelial cells. Insights into the possible functions of PSMA should improve the diagnostic and therapeutic values of this clinically important molecule.
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Affiliation(s)
- Ayyappan K Rajasekaran
- Dept. of Pathology and Laboratory Medicine, David Geffen School of Medicine, Univ. of California, Los Angeles, 10833 Le Conte Ave., Rm. 13-344, CHS, Los Angeles, CA 90095, USA.
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Davis MI, Bennett MJ, Thomas LM, Bjorkman PJ. Crystal structure of prostate-specific membrane antigen, a tumor marker and peptidase. Proc Natl Acad Sci U S A 2005; 102:5981-6. [PMID: 15837926 PMCID: PMC556220 DOI: 10.1073/pnas.0502101102] [Citation(s) in RCA: 194] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Prostate-specific membrane antigen (PSMA) is highly expressed in prostate cancer cells and nonprostatic solid tumor neovasculature and is a target for anticancer imaging and therapeutic agents. PSMA acts as a glutamate carboxypeptidase (GCPII) on small molecule substrates, including folate, the anticancer drug methotrexate, and the neuropeptide N-acetyl-l-aspartyl-l-glutamate. Here we present the 3.5-A crystal structure of the PSMA ectodomain, which reveals a homodimer with structural similarity to transferrin receptor, a receptor for iron-loaded transferrin that lacks protease activity. Unlike transferrin receptor, the protease domain of PSMA contains a binuclear zinc site, catalytic residues, and a proposed substrate-binding arginine patch. Elucidation of the PSMA structure combined with docking studies and a proposed catalytic mechanism provides insight into the recognition of inhibitors and the natural substrate N-acetyl-l-aspartyl-l-glutamate. The PSMA structure will facilitate development of chemotherapeutics, cancer-imaging agents, and agents for treatment of neurological disorders.
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Affiliation(s)
- Mindy I Davis
- Division of Biology 114-96 and Howard Hughes Medical Institute, California Institute of Technology, Pasadena, CA 91125, USA
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28
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Abstract
Abstract
Prostate-specific membrane antigen (PSMA), a type II transmembrane glycoprotein, is overexpressed in prostate cancer. PSMA is a unique cell surface marker, negatively regulated by androgen and extensively used for imaging of hormone refractory carcinomas and metastatic foci. PSMA is a carboxypeptidase with two important enzymatic functions, namely, folate hydrolase and NAALADase. PSMA also exhibits an endocytic function, in which it spontaneously recycles through endocytic vesicles. PSMA is overexpressed at various stages of prostate cancer, including androgen-sensitive and -independent disease, increased in expression with early relapse after therapy. We have used in vitro invasion assays to explore the possible role of PSMA in the metastasis of prostate cancer cells. Androgen-dependent prostate cancer lines, which express PSMA endogenously (e.g., LNCaP, MDA PCa2b, and CWR22Rv1) are less invasive compared with androgen-independent PC3 or DU145 cells, neither of which expresses PSMA. Ectopic expression of PSMA in PC3 cells reduced the invasiveness of these cells, suggesting that this reduction in the invasion capability of PSMA-expressing cells is due to PSMA expression and not to intrinsic properties of different prostate cancer cell lines. Furthermore, knockdown of PSMA expression increased invasiveness of LNCaP cells by 5-fold. Finally, expression of PSMA mutants lacking carboxypeptidase activity reduced the impact of PSMA expression on invasiveness. Thus, it seems that the enzymatic activity is associated with the effect of PSMA on invasiveness.
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Barinka C, Sácha P, Sklenár J, Man P, Bezouska K, Slusher BS, Konvalinka J. Identification of the N-glycosylation sites on glutamate carboxypeptidase II necessary for proteolytic activity. Protein Sci 2005; 13:1627-35. [PMID: 15152093 PMCID: PMC2279971 DOI: 10.1110/ps.04622104] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Glutamate carboxypeptidase II (GCPII) is a membrane peptidase expressed in the prostate, central and peripheral nervous system, kidney, small intestine, and tumor-associated neovasculature. The GCPII form expressed in the central nervous system, termed NAALADase, is responsible for the cleavage of N-acetyl-L-aspartyl-L-glutamate (NAAG) yielding free glutamate in the synaptic cleft, and is implicated in various pathologic conditions associated with glutamate excitotoxicity. The prostate form of GCPII, termed prostate-specific membrane antigen (PSMA), is up-regulated in cancer and used as an effective prostate cancer marker. Little is known about the structure of this important pharmaceutical target. As a type II membrane protein, GCPII is heavily glycosylated. In this paper we show that N-glycosylation is vital for proper folding and subsequent secretion of human GCPII. Analysis of the predicted N-glycosylation sites also provides evidence that these sites are critical for GCPII carboxypeptidase activity. We confirm that all predicted N-glycosylation sites are occupied by an oligosaccharide moiety and show that glycosylation at sites distant from the putative catalytic domain is critical for the NAAG-hydrolyzing activity of GCPII calling the validity of previously described structural models of GCPII into question.
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Affiliation(s)
- Cyril Barinka
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo n. 2, 166 10 Praha 6, Czech Republic
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Ghosh A, Heston WDW. Tumor target prostate specific membrane antigen (PSMA) and its regulation in prostate cancer. J Cell Biochem 2004; 91:528-39. [PMID: 14755683 DOI: 10.1002/jcb.10661] [Citation(s) in RCA: 613] [Impact Index Per Article: 30.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Prostate specific membrane antigen (PSMA), is a unique membrane bound glycoprotein, which is overexpressed manifold on prostate cancer as well as neovasculature of most of the solid tumors, but not in the vasculature of the normal tissues. This unique expression of PSMA makes it an important marker as well as a large extracellular target of imaging agents. PSMA can serve as target for delivery of therapeutic agents such as cytotoxins or radionuclides. PSMA has two unique enzymatic functions, folate hydrolase and NAALADase and found to be recycled like other membrane bound receptors through clathrin coated pits. The internalization property of PSMA leads one to consider the potential existence of a natural ligand for PSMA. In this review we have discussed the regulation of PSMA expression within the cells, and significance of its expression in prostate cancer and metastasis.
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Affiliation(s)
- Arundhati Ghosh
- George M O'Brien Center for Urology Research, Department of Cancer Biology, Lerner Research Institute, Cleveland, Ohio 44195, USA
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O'Keefe DS, Bacich DJ, Heston WDW. Comparative analysis of prostate-specific membrane antigen (PSMA) versus a prostate-specific membrane antigen-like gene. Prostate 2004; 58:200-10. [PMID: 14716746 DOI: 10.1002/pros.10319] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
BACKGROUND Currently prostate-specific membrane antigen (PSMA) is showing promise both as an imaging and therapeutic target for occult prostate cancer metastases. First generation antibodies against PSMA are used for the FDA approved Prostascint trade mark monoclonal antibody scan and second generation antibodies are being developed for therapeutic targeting as well as imaging 1. However, there have been reports describing PSMA expression in non-prostatic tissues including kidney, liver, and brain. As we had previously showed the existence of a human PSMA homolog, we set out to determine if this non-prostatic expression was due to expression of the PSMA or another gene. MATERIALS AND METHODS The PSMA homolog (PSMA-like) cDNA was cloned by screening a liver cDNA library. mRNA expression of the PSMA and PSMA-like genes was determined via Northern blot analysis using two different probes and protein expression confirmed in some tissues via Western blot analysis. Transcriptional regulation of the two genes was examined using reporter constructs driving luciferase expression. RESULTS The PSMA-like gene possesses 98% identity to the PSMA gene at the nucleotide level and is expressed in kidney and liver under the control of a different promoter to the PSMA gene. The PSMA gene is expressed in several human tissues and is most abundant in the nervous system and the prostate. CONCLUSION The non-prostatic expression of PSMA should be taken into consideration when designing clinical strategies targeting PSMA.
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Affiliation(s)
- Denise S O'Keefe
- The Department of Urology, University of Pittsburgh Cancer Institute, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
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