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Vonniessen B, Tabariès S, Siegel PM. Antibody-mediated targeting of Claudins in cancer. Front Oncol 2024; 14:1320766. [PMID: 38371623 PMCID: PMC10869466 DOI: 10.3389/fonc.2024.1320766] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2023] [Accepted: 01/09/2024] [Indexed: 02/20/2024] Open
Abstract
Tight junctions (TJs) are large intercellular adhesion complexes that maintain cell polarity in normal epithelia and endothelia. Claudins are critical components of TJs, forming homo- and heteromeric interaction between adjacent cells, which have emerged as key functional modulators of carcinogenesis and metastasis. Numerous epithelial-derived cancers display altered claudin expression patterns, and these aberrantly expressed claudins have been shown to regulate cancer cell proliferation/growth, metabolism, metastasis and cell stemness. Certain claudins can now be used as biomarkers to predict patient prognosis in a variety of solid cancers. Our understanding of the distinct roles played by claudins during the cancer progression has progressed significantly over the last decade and claudins are now being investigated as possible diagnostic markers and therapeutic targets. In this review, we will summarize recent progress in the use of antibody-based or related strategies for targeting claudins in cancer treatment. We first describe pre-clinical studies that have facilitated the development of neutralizing antibodies and antibody-drug-conjugates targeting Claudins (Claudins-1, -3, -4, -6 and 18.2). Next, we summarize clinical trials assessing the efficacy of antibodies targeting Claudin-6 or Claudin-18.2. Finally, emerging strategies for targeting Claudins, including Chimeric Antigen Receptor (CAR)-T cell therapy and Bi-specific T cell engagers (BiTEs), are also discussed.
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Affiliation(s)
- Benjamin Vonniessen
- Goodman Cancer Institute, McGill University, Montréal, QC, Canada
- Department of Medicine, McGill University, Montréal, QC, Canada
| | - Sébastien Tabariès
- Goodman Cancer Institute, McGill University, Montréal, QC, Canada
- Department of Medicine, McGill University, Montréal, QC, Canada
| | - Peter M. Siegel
- Goodman Cancer Institute, McGill University, Montréal, QC, Canada
- Department of Medicine, McGill University, Montréal, QC, Canada
- Department of Biochemistry, McGill University, Montréal, QC, Canada
- Department of Anatomy & Cell Biology, McGill University, Montréal, QC, Canada
- Department of Oncology, McGill University, Montréal, QC, Canada
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2
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Mikuteit M, Zschäbitz S, Stöhr C, Herrmann E, Polifka I, Agaimy A, Trojan L, Ströbel P, Becker F, Wülfing C, Barth P, Stöckle M, Staehler M, Stief C, Haferkamp A, Hohenfellner M, Duensing S, Macher-Göppinger S, Wullich B, Noldus J, Brenner W, Roos F, Walter B, Otto W, Burger M, Erlmeier M, Schrader AJ, Hartmann A, Erlmeier F, Steffens S. Evaluation of Gas 6 as a Prognostic Marker in Papillary Renal Cell Carcinoma. Urol Int 2023; 107:713-722. [PMID: 37348477 PMCID: PMC10413799 DOI: 10.1159/000529898] [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: 08/04/2022] [Accepted: 02/06/2023] [Indexed: 06/24/2023]
Abstract
INTRODUCTION Growth arrest-specific protein 6 (Gas 6) is a ligand that plays a role in proliferation and migration of cells. For several tumor entities, high levels of Gas 6 are associated with poorer survival. We examined the prognostic role of Gas 6 in renal cell carcinoma (RCC), especially in papillary RCC (pRCC), which is still unclear. METHODS The patients' sample collection is a joint collaboration of the PANZAR consortium. Patients' medical history and tumor specimens were collected from n = 240 and n = 128 patients with type 1 and 2 pRCC, respectively. Expression of Gas 6 was determined by immunohistochemistry. RESULTS In total, Gas 6 staining was evaluable in 180 of 240 type 1 and 110 of 128 type 2 pRCC cases. Kaplan-Meier analysis disclosed no significant difference in 5-year overall survival for all pRCC nor either subtype. Also, Gas+ and Gas- groups did not significantly differ in any tumor or patient characteristics. CONCLUSION Gas 6 was not found to be an independent prognostic marker in pRCC. Future studies are warranted to determine if Gas 6 plays a role as prognostic marker or therapeutic target in pRCC.
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Affiliation(s)
- Marie Mikuteit
- Department of Rheumatology and Immunology, Hannover Medical School, Hannover, Germany
- Dean’s Office, Curriculum Development, Hannover Medical School, Hannover, Germany
| | - Stefanie Zschäbitz
- Department of Medical Oncology, National Center of Tumor Diseases, University Hospital Heidelberg, Heidelberg, Germany
| | - Christine Stöhr
- Institute of Pathology, University Hospital Erlangen-Nuernberg, Friedrich Alexander University (FAU), Erlangen, Germany
| | - Edwin Herrmann
- Department of Urology, University Hospital Muenster, Muenster, Germany
| | - Iris Polifka
- Institute of Pathology, University Hospital Erlangen-Nuernberg, Friedrich Alexander University (FAU), Erlangen, Germany
| | - Abbas Agaimy
- Institute of Pathology, University Hospital Erlangen-Nuernberg, Friedrich Alexander University (FAU), Erlangen, Germany
| | - Lutz Trojan
- Department of Urology, University Hospital Göttingen, Göttingen, Germany
| | - Philipp Ströbel
- Department of Pathology, University Hospital Göttingen, Göttingen, Germany
| | - Frank Becker
- Department of Urology and Pediatric Urology, University of Saarland (UKS), Homburg, Germany
| | - Christian Wülfing
- Institute of Pathology, University Hospital Göttingen, Göttingen, Germany
| | - Peter Barth
- Department of Urology, University of Marburg, Marburg, Germany
| | - Michael Stöckle
- Department of Urology and Pediatric Urology, University of Saarland (UKS), Homburg, Germany
| | - Michael Staehler
- Department of Urology, University Hospital Munich, Munich, Germany
| | - Christian Stief
- Department of Urology, University Hospital Munich, Munich, Germany
| | - Axel Haferkamp
- Department of Urology, University Hospital Mainz, Mainz, Germany
| | | | - Stefan Duensing
- Department of Urology, University Hospital Heidelberg, Heidelberg, Germany
| | | | - Bernd Wullich
- Department of Urology and Pediatric Urology, University Hospital Erlangen, Friedrich Alexander University Erlangen-Nürnberg, Erlangen, Germany
| | - Joachim Noldus
- Department of Urology, Marien Hospital Herne, Ruhr University Bochum, Herne, Germany
| | - Walburgis Brenner
- Clinic for Obstretics and Woman's Health and Department of Urology, University Medical Center, Mainz, Germany
- Department of Urology, University of Mainz, Mainz, Germany
| | - Frederik Roos
- Department of Urology, University Hospital Frankfurt, Frankfurt/Main, Germany
| | - Bernhard Walter
- Department of Urology and Pediatric Urology, University Hospital Erlangen, Friedrich Alexander University Erlangen-Nürnberg, Erlangen, Germany
| | - Wolfgang Otto
- Department of Urology, University of Regensburg, Regensburg, Germany
| | - Maximilian Burger
- Department of Urology, University of Regensburg, Regensburg, Germany
| | | | | | - Arndt Hartmann
- Institute of Pathology, University Hospital Erlangen-Nuernberg, Friedrich Alexander University (FAU), Erlangen, Germany
| | - Franziska Erlmeier
- Institute of Pathology, University Hospital Erlangen-Nuernberg, Friedrich Alexander University (FAU), Erlangen, Germany
| | - Sandra Steffens
- Department of Rheumatology and Immunology, Hannover Medical School, Hannover, Germany
- Dean’s Office, Curriculum Development, Hannover Medical School, Hannover, Germany
| | - German Network of Kidney Cancer
- Department of Rheumatology and Immunology, Hannover Medical School, Hannover, Germany
- Dean’s Office, Curriculum Development, Hannover Medical School, Hannover, Germany
- Department of Medical Oncology, National Center of Tumor Diseases, University Hospital Heidelberg, Heidelberg, Germany
- Institute of Pathology, University Hospital Erlangen-Nuernberg, Friedrich Alexander University (FAU), Erlangen, Germany
- Department of Urology, University Hospital Muenster, Muenster, Germany
- Department of Urology, University Hospital Göttingen, Göttingen, Germany
- Department of Pathology, University Hospital Göttingen, Göttingen, Germany
- Department of Urology and Pediatric Urology, University of Saarland (UKS), Homburg, Germany
- Institute of Pathology, University Hospital Göttingen, Göttingen, Germany
- Department of Urology, University of Marburg, Marburg, Germany
- Department of Urology, University Hospital Munich, Munich, Germany
- Department of Urology, University Hospital Mainz, Mainz, Germany
- Department of Urology, University Hospital Heidelberg, Heidelberg, Germany
- Institute of Pathology, University Hospital Mainz, Mainz, Germany
- Department of Urology and Pediatric Urology, University Hospital Erlangen, Friedrich Alexander University Erlangen-Nürnberg, Erlangen, Germany
- Department of Urology, Marien Hospital Herne, Ruhr University Bochum, Herne, Germany
- Clinic for Obstretics and Woman's Health and Department of Urology, University Medical Center, Mainz, Germany
- Department of Urology, University of Mainz, Mainz, Germany
- Department of Urology, University Hospital Frankfurt, Frankfurt/Main, Germany
- Department of Urology, University of Regensburg, Regensburg, Germany
- Department of Urology, München Klinik Bogenhausen, Munich, Germany
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3
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Erlmeier M, Mikuteit M, Zschäbitz S, Autenrieth M, Weichert W, Hartmann A, Steffens S, Erlmeier F. Immunohistochemical expression of the hepatocyte growth factor in chromophobe renal cell carcinoma. BMC Urol 2023; 23:90. [PMID: 37170275 PMCID: PMC10176764 DOI: 10.1186/s12894-023-01263-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2022] [Accepted: 04/28/2023] [Indexed: 05/13/2023] Open
Abstract
BACKGROUND The prognostic value of Hepatocyte growth factor (HGF) in non-clear cell renal cell carcinoma (RCC) is still unclear. The aim of this study is to evaluate the prognostic impact of HGF expression in a large cohort of chromophobe RCC (chRCC). METHODS Patients who underwent renal surgery due to chRCC were recruited. Clinical data was retrospectively evaluated. Tumor specimen were analyzed for HGF expression by immunohistochemistry. RESULTS 81 chRCC patients were eligible for analysis, thereof 37 (45.7%) patients were positive for HGF. No significant associations were found for HGF expression and clinical attributes in patients with chRCC. Kaplan-Meier analysis revealed no differences in 5-year overall survival (OS) for patients with HGF- compared to HGF+ tumors (95.0% versus 90.9%; p = 0.410). CONCLUSIONS In chRCC HGF expression is not associated with parameters of aggressiveness or survival.
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Affiliation(s)
| | - Marie Mikuteit
- Department for Rheumatology and Immunology, Hannover Medical School, Carl-Neuberg-Straße 1, 30625, Hannover, Germany.
| | - Stefanie Zschäbitz
- Dept. of Medical Oncology, National Center of Tumor Diseases, University Hospital Heidelberg, Heidelberg, Germany
| | - Michael Autenrieth
- Department of Urology, Technical University of Munich, Klinikum Rechts der Isar, München, Germany
| | - Wilko Weichert
- Institute for Pathology and Pathological Anatomy, Technical University Munich, Munich, Germany
| | - Arndt Hartmann
- Institute of Pathology, University Hospital of Erlangen, Erlangen, Germany
| | - Sandra Steffens
- Department for Rheumatology and Immunology, Hannover Medical School, Carl-Neuberg-Straße 1, 30625, Hannover, Germany
- Department of Urology, University Hospital Münster, Münster, Germany
| | - Franziska Erlmeier
- Institute of Pathology, University Hospital of Erlangen, Erlangen, Germany
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4
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Erlmeier F, Zschäbitz S, Mikuteit M, Autenrieth M, Weichert W, Hartmann A, Steffens S. The role of claudin-6 in chromophobe renal cell carcinoma. Histol Histopathol 2023; 38:403-407. [PMID: 36128931 DOI: 10.14670/hh-18-520] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/01/2023]
Abstract
BACKGROUND The prognostic value of Claudin-6 (CLDN6) in non clear cell renal cell carcinoma (RCC) is still unclear. AIM To evaluate the prognostic impact of CLDN6 expression in a large cohort of chromophobe RCC (chRCC). MATERIAL AND METHODS Patients who underwent renal surgery due to chRCC were recruited. Clinical data were retrospectively evaluated. Tumor specimens were analyzed for CLDN6 expression by immunohistochemistry. RESULTS 81 chRCC patients were eligible for analysis, thereof 10 (12.3%) patients were positive for CLDN6. No significant associations were found for CLDN6 expression and clinical attributes in patients with chRCC. Kaplan-Meier analysis revealed no differences in overall survival (OS) for patients with CLDN6⁻ compared to CLDN6⁺ tumors (87.0% versus 62.5%; p=0.174). CONCLUSION In chRCC CLDN6 expression is not associated with parameters of aggressiveness or survival. Due to the rare incidence of chRCC further studies with larger cohorts are warranted.
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Affiliation(s)
- Franziska Erlmeier
- Institute of Pathology, University Hospital of Erlangen, Erlangen, Germany.
| | - Stefanie Zschäbitz
- Department of Medical Oncology, National Center of Tumor Diseases, University Hospital Heidelberg, Heidelberg, Germany
| | - Marie Mikuteit
- Department for Rheumatology and Immunology, Hannover Medical School, Hannover, Germany
| | - Michael Autenrieth
- Department of Urology, Technical University of Munich, Klinikum rechts der Isar, Munich, Germany
| | - Wilko Weichert
- Institute for Pathology and Pathological Anatomy, Technical University Munich, Munich, Germany
- Member of the German Cancer Consortium (DKTK), Germany
| | - Arndt Hartmann
- Institute of Pathology, University Hospital of Erlangen, Erlangen, Germany
| | - Sandra Steffens
- Department for Rheumatology and Immunology, Hannover Medical School, Hannover, Germany
- Department of Urology, University Hospital Münster, Münster, Germany
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5
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Screnci B, Stafford LJ, Barnes T, Shema K, Gilman S, Wright R, Al Absi S, Phillips T, Azuelos C, Slovik K, Murphy P, Harmon DB, Charpentier T, Doranz BJ, Rucker JB, Chambers R. Antibody specificity against highly conserved membrane protein Claudin 6 driven by single atomic contact point. iScience 2022; 25:105665. [PMID: 36505931 PMCID: PMC9732412 DOI: 10.1016/j.isci.2022.105665] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Revised: 09/20/2022] [Accepted: 11/21/2022] [Indexed: 11/25/2022] Open
Abstract
The tight junction protein claudin 6 (CLDN6) is differentially expressed on cancer cells with almost no expression in healthy tissue. However, achieving therapeutic MAb specificity for this 4 transmembrane protein is challenging because it is nearly identical to the widely expressed CLDN9, with only 3 extracellular amino acids different. Most other CLDN6 MAbs, including those in clinical development are cross-reactive with CLDN9, and several trials have now been stopped. Here we isolated rare MAbs that bind CLDN6 with up to picomolar affinity and display minimal cross-reactivity with CLDN9, 22 other CLDN family members, or across the human membrane proteome. Amino acid-level epitope mapping distinguished the binding sites of our MAbs from existing clinical-stage MAbs. Atomic-level epitope mapping identified the structural mechanism by which our MAbs differentiate CLDN6 and CLDN9 through steric hindrance at a single molecular contact point, the γ carbon on CLDN6 residue Q156.
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Affiliation(s)
- Brad Screnci
- Integral Molecular, 3711 Market Street, Suite 900, Philadelphia, PA 19104, USA
| | - Lewis J. Stafford
- Integral Molecular, 3711 Market Street, Suite 900, Philadelphia, PA 19104, USA
| | - Trevor Barnes
- Integral Molecular, 3711 Market Street, Suite 900, Philadelphia, PA 19104, USA
| | - Kristen Shema
- Integral Molecular, 3711 Market Street, Suite 900, Philadelphia, PA 19104, USA
| | - Samantha Gilman
- Integral Molecular, 3711 Market Street, Suite 900, Philadelphia, PA 19104, USA
| | - Rebecca Wright
- Integral Molecular, 3711 Market Street, Suite 900, Philadelphia, PA 19104, USA
| | - Suzie Al Absi
- Integral Molecular, 3711 Market Street, Suite 900, Philadelphia, PA 19104, USA
| | - Tim Phillips
- Integral Molecular, 3711 Market Street, Suite 900, Philadelphia, PA 19104, USA
| | - Charles Azuelos
- Integral Molecular, 3711 Market Street, Suite 900, Philadelphia, PA 19104, USA
| | - Katherine Slovik
- Integral Molecular, 3711 Market Street, Suite 900, Philadelphia, PA 19104, USA
| | - Paige Murphy
- Integral Molecular, 3711 Market Street, Suite 900, Philadelphia, PA 19104, USA
| | - Daniel B. Harmon
- Integral Molecular, 3711 Market Street, Suite 900, Philadelphia, PA 19104, USA
| | - Tom Charpentier
- Integral Molecular, 3711 Market Street, Suite 900, Philadelphia, PA 19104, USA
| | - Benjamin J. Doranz
- Integral Molecular, 3711 Market Street, Suite 900, Philadelphia, PA 19104, USA
| | - Joseph B. Rucker
- Integral Molecular, 3711 Market Street, Suite 900, Philadelphia, PA 19104, USA
| | - Ross Chambers
- Integral Molecular, 3711 Market Street, Suite 900, Philadelphia, PA 19104, USA,Corresponding author
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6
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Knockdown of CLAUDIN-6 Inhibited Apoptosis and Induced Proliferation of Bovine Cumulus Cells. Int J Mol Sci 2022; 23:ijms232113222. [PMID: 36362009 PMCID: PMC9656489 DOI: 10.3390/ijms232113222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Revised: 10/19/2022] [Accepted: 10/21/2022] [Indexed: 11/17/2022] Open
Abstract
This study aims to investigate the effects of CLAUDIN-6 (CLDN6) on cell apoptosis and proliferation of bovine cumulus cells (CCs). Immunofluorescence staining was used to localize CLDN6 protein in CCs. Three pairs of siRNA targeting CLDN6 and one pair of siRNA universal negative sequence as control were transfected into bovine CCs. Then, the effective siRNA was screened by real-time quantitative PCR (RT-qPCR) and Western blotting. The mRNA expression levels of apoptosis related genes (CASPASE-3, BAX and BCL-2) and proliferation related genes (PCNA, CDC42 and CCND2) were evaluated by RT-qPCR in CCs with CLDN6 knockdown. Cell proliferation, apoptosis and cell cycle were detected by flow cytometry with CCK-8 staining, Annexin V-FITC staining and propidium iodide staining, respectively. Results showed that the CLDN6 gene was expressed in bovine CCs and the protein was localized in cell membranes and cytoplasms. After CLDN6 was knocked down in CCs, the cell apoptosis rate significantly decreased and the pro-apoptotic genes BAX and CASPASE-3 were down-regulated significantly, whereas the anti-apoptotic gene BCL-2 was markedly up-regulated (p < 0.05). Additionally, CLDN6 knockdown significantly enhanced cell proliferation of CCs at 72 h after siRNA transfection. The mRNA levels of proliferation-related genes PCNA, CCND2 and CDC42 increased obviously in CCs with CLDN6 knockdown (p < 0.05). After CLDN6 was down-regulated, the percentage of CCs at S phase was significantly increased (p < 0.05). However, there was no remarkable difference in the percentages of cells at the G0/G1 phase and G2/M phase between CCs with or without CLDN6 knockdown (p > 0.05). Therefore, the expression of CLDN6 and its effects on cell proliferation, apoptosis and cell cycle of bovine CCs were first studied. CLDN6 low expression inhibited cell apoptosis, induced cell proliferation and cell cycle arrest of bovine CCs.
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7
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Qu H, Wang M, Wang M, Liu Y, Quan C. The expression and the tumor suppressor role of CLDN6 in colon cancer. Mol Cell Biochem 2022; 477:2883-2893. [PMID: 35701678 DOI: 10.1007/s11010-022-04450-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Accepted: 04/24/2022] [Indexed: 11/29/2022]
Abstract
As a member of the tight junction family, CLDN6 is a tumor suppressor in breast cancer, but its role in colon cancer is unknown. In this research, we aimed at revealing the function of CLDN6 in colon cancer. We found that colon cancer tissues lowly expressed CLDN6, and the expression of CLDN6 was negatively correlated with lymph node metastasis. Similarly, CLDN6 was lowly expressed in the colon cancer cell line SW1116, and overexpression of CLDN6 inhibited cell proliferation in vitro and in vivo. Consistently, the migration and invasion abilities of cells were significantly inhibited after CLDN6 overexpression. In addition, we demonstrated that CLDN6 may inhibit the migration and invasion abilities by activating the TYK2/STAT3 pathway. Therefore, our data indicated that CLDN6 acted as a tumor suppressor and had the potential to be regarded as a biomarker for the progression of colon cancer.
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Affiliation(s)
- Huinan Qu
- The Key Laboratory of Pathobiology, Ministry of Education, College of Basic Medical Sciences, Jilin University, 126 Xinmin Avenue, Changchun, 130021, Jilin, People's Republic of China
| | - Min Wang
- The Key Laboratory of Pathobiology, Ministry of Education, College of Basic Medical Sciences, Jilin University, 126 Xinmin Avenue, Changchun, 130021, Jilin, People's Republic of China
| | - Miaomiao Wang
- The Key Laboratory of Pathobiology, Ministry of Education, College of Basic Medical Sciences, Jilin University, 126 Xinmin Avenue, Changchun, 130021, Jilin, People's Republic of China
| | - Yuanyuan Liu
- The Key Laboratory of Pathobiology, Ministry of Education, College of Basic Medical Sciences, Jilin University, 126 Xinmin Avenue, Changchun, 130021, Jilin, People's Republic of China
| | - Chengshi Quan
- The Key Laboratory of Pathobiology, Ministry of Education, College of Basic Medical Sciences, Jilin University, 126 Xinmin Avenue, Changchun, 130021, Jilin, People's Republic of China.
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8
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Mikuteit M, Zschäbitz S, Stöhr C, Herrmann E, Polifka I, Agaimy A, Trojan L, Ströbel P, Becker F, Wülfing C, Barth P, Stöckle M, Staehler M, Stief C, Haferkamp A, Hohenfellner M, Macher-Göppinger S, Wullich B, Noldus J, Brenner W, Roos FC, Walter B, Otto W, Burger M, Schrader AJ, Hartmann A, Steffens S, Erlmeier F. The prognostic impact of Claudin 6 in papillary renal cell carcinoma. Pathol Res Pract 2022; 231:153802. [DOI: 10.1016/j.prp.2022.153802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Revised: 02/07/2022] [Accepted: 02/09/2022] [Indexed: 11/25/2022]
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9
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Qu H, Jin Q, Quan C. CLDN6: From Traditional Barrier Function to Emerging Roles in Cancers. Int J Mol Sci 2021; 22:ijms222413416. [PMID: 34948213 PMCID: PMC8705207 DOI: 10.3390/ijms222413416] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Revised: 12/06/2021] [Accepted: 12/12/2021] [Indexed: 02/07/2023] Open
Abstract
Claudins (CLDNs) are the most important tight junction proteins, which are mainly expressed in endothelial cells or epithelial cells in a tissue-specific manner. As a member of the CLDNs family, CLDN6 is highly expressed in fetal tissues such as the stomach, pancreas, lung, and kidney, but is not expressed in corresponding adult tissues. The expression of CLDN6 is regulated by a variety of factors, including but not limited to stimuli and transcription factors, DNA methylation, and post-translational modifications. CLDN6 has been found to have a key role in the formation of barriers, especially the lung epithelial barrier and the epidermal permeability barrier (EPB). Importantly, the roles of CLDN6 in cancers have gained focus and are being investigated in recent years. Strong evidence indicates that the altered expression of CLDN6 is linked to the development of various cancers. Malignant phenotypes of tumors affected by CLDN6 include proliferation and apoptosis, migration and invasion, and drug resistance, which are regulated by CLDN6-mediated key signaling pathways. Given the important role in tumors and its low or no expression in normal tissues, CLDN6 is an ideal target for tumor therapy. This review aims to provide an overview of the structure and regulation of CLDN6, and its traditional barrier function, with a special emphasis on its emerging roles in cancers, including its impact on the malignant phenotypes, signal-modulating effects, the prognosis of tumor patients, and clinical applications in cancers.
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10
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Zhang C, Guo C, Li Y, Liu K, Zhao Q, Ouyang L. Identification of Claudin-6 as a Molecular Biomarker in Pan-Cancer Through Multiple Omics Integrative Analysis. Front Cell Dev Biol 2021; 9:726656. [PMID: 34409042 PMCID: PMC8365468 DOI: 10.3389/fcell.2021.726656] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Accepted: 07/08/2021] [Indexed: 12/13/2022] Open
Abstract
Claudin-6 (CLDN6) is one of the 27 family members of claudins and majorly involved in the tight junction and cell-to-cell adhesion of epithelial cell sheets, playing a significant role in cancer initiation and progression. To provide a more systematic and comprehensive dimension of identifying the diverse significance of CLDN6 in a variety of malignant tumors, we explored CLDN6 through multiple omics data integrative analysis, including gene expression level in pan-cancer and comparison of CLDN6 expression in different molecular subtypes and immune subtypes of pan-cancer, targeted protein, biological functions, molecular signatures, diagnostic value, and prognostic value in pan-cancer. Furthermore, we focused on uterine corpus endometrial carcinoma (UCEC) and further investigated CLDN6 from the perspective of the correlations with clinical characteristics, prognosis in different clinical subgroups, co-expression genes, and differentially expressed genes (DEGs), basing on discussing the validation of its established monoclonal antibody by immunohistochemical staining and semi-quantification reported in the previous study. As a result, CLDN6 expression differs significantly not only in most cancers but also in different molecular and immune subtypes of cancers. Besides, high accuracy in predicting cancers and notable correlations with prognosis of certain cancers suggest that CLDN6 might be a potential diagnostic and prognostic biomarker of cancers. Additionally, CLDN6 is identified to be significantly correlated with age, stage, weight, histological type, histologic grade, and menopause status in UCEC. Moreover, CLDN6 high expression can lead to a worse overall survival (OS), disease-specific survival (DSS), and progression-free interval (PFI) in UCEC, especially in different clinical subgroups of UCEC. Taken together, CLDN6 may be a remarkable molecular biomarker for diagnosis and prognosis in pan-cancer and an independent prognostic risk factor of UCEC, presenting to be a promising molecular target for cancer therapy.
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Affiliation(s)
- Chiyuan Zhang
- Department of Obstetrics and Gynecology, Shengjing Hospital of China Medical University, Shenyang, China
| | - Cuishan Guo
- Department of Obstetrics and Gynecology, Shengjing Hospital of China Medical University, Shenyang, China
| | - Yan Li
- Department of Obstetrics and Gynecology, Shengjing Hospital of China Medical University, Shenyang, China
| | - Kuiran Liu
- Department of Obstetrics and Gynecology, Shengjing Hospital of China Medical University, Shenyang, China
| | - Qi Zhao
- School of Computer Science and Software Engineering, University of Science and Technology Liaoning, Anshan, China
| | - Ling Ouyang
- Department of Obstetrics and Gynecology, Shengjing Hospital of China Medical University, Shenyang, China
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11
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Du H, Yang X, Fan J, Du X. Claudin 6: Therapeutic prospects for tumours, and mechanisms of expression and regulation (Review). Mol Med Rep 2021; 24:677. [PMID: 34296304 PMCID: PMC8335585 DOI: 10.3892/mmr.2021.12316] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2020] [Accepted: 06/30/2021] [Indexed: 12/13/2022] Open
Abstract
Tight junctions (TJs) are an important component of cell connectivity; they maintain cell polarity, permeability and adhesion, and participate in the regulation of cell proliferation and differentiation. The claudin (CLDN) family is integral to TJs, and CLDN6 is an important member of this family. Abnormal expression of CLDN6 can destroy the integrity of TJs through various mechanisms and can serve multiple roles in the occurrence and development of tumours. CLDN6 is widely expressed in various tumours but rarely expressed in healthy adult tissues. The aim of this review is to critically examine the recent literature on CLDN6, including its structure, expression in different tumours, regulatory mechanisms and therapeutic prospects. Although some conclusions are controversial, in certain tumours, such as liver, ovarian, endometrial and oesophageal cancer, and atypical teratoid/rhabdoid tumours, research consistently shows that CLDN6 is expressed in tumour tissues but is not expressed or is expressed at low levels in surrounding tissues. In these tumours, CLDN6 has potential as a carcinoembryonic antigen and a therapeutic target.
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Affiliation(s)
- Huan Du
- Department of Oncology, Mianyang Central Hospital, Mianyang, Sichuan 621000, P.R. China
| | - Xiyue Yang
- Department of Oncology, Affiliated Hospital of North Sichuan Medical College, Nanchong, Sichuan 637000, P.R. China
| | - Jinjia Fan
- Department of Oncology, Affiliated Hospital of North Sichuan Medical College, Nanchong, Sichuan 637000, P.R. China
| | - Xiaobo Du
- Department of Oncology, Mianyang Central Hospital, Mianyang, Sichuan 621000, P.R. China
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Uc PY, Miranda J, Raya-Sandino A, Alarcón L, Roldán ML, Ocadiz-Delgado R, Cortés-Malagón EM, Chávez-Munguía B, Ramírez G, Asomoza R, Shoshani L, Gariglio P, González-Mariscal L. E7 oncoprotein from human papillomavirus 16 alters claudins expression and the sealing of epithelial tight junctions. Int J Oncol 2020; 57:905-924. [PMID: 32945372 PMCID: PMC7473757 DOI: 10.3892/ijo.2020.5105] [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: 01/26/2020] [Accepted: 04/16/2020] [Indexed: 11/24/2022] Open
Abstract
Tight junctions (TJs) are cell-cell adhesion structures frequently altered by oncogenic transformation. In the present study the role of human papillomavirus (HPV) 16 E7 oncoprotein on the sealing of TJs was investigated and also the expression level of claudins in mouse cervix and in epithelial Madin-Darby Canine Kidney (MDCK) cells. It was found that there was reduced expression of claudins -1 and -10 in the cervix of 7-month-old transgenic K14E7 mice treated with 17β-estradiol (E2), with invasive cancer. In addition, there was also a transient increase in claudin-1 expression in the cervix of 2-month-old K14E7 mice, and claudin-10 accumulated at the border of cells in the upper layer of the cervix in FvB mice treated with E2, and in K14E7 mice treated with or without E2. These changes were accompanied by an augmented paracellular permeability of the cervix in 2- and 7-monthold FvB mice treated with E2, which became more pronounced in K14E7 mice treated with or without E2. In MDCK cells the stable expression of E7 increased the space between adjacent cells and altered the architecture of the monolayers, induced the development of an acute peak of transepithelial electrical resistance accompanied by a reduced expression of claudins -1, -2 and -10, and an increase in claudin-4. Moreover, E7 enhances the ability of MDCK cells to migrate through a 3D matrix and induces cell stiffening and stress fiber formation. These observations revealed that cell transformation induced by HPV16 E7 oncoprotein was accompanied by changes in the pattern of expression of claudins and the degree of sealing of epithelial TJs.
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Affiliation(s)
- Perla Yaceli Uc
- Department of Physiology, Biophysics and Neuroscience, Center for Research and Advanced Studies, Mexico City 07360, Mexico
| | - Jael Miranda
- Department of Physiology, Biophysics and Neuroscience, Center for Research and Advanced Studies, Mexico City 07360, Mexico
| | - Arturo Raya-Sandino
- Department of Physiology, Biophysics and Neuroscience, Center for Research and Advanced Studies, Mexico City 07360, Mexico
| | - Lourdes Alarcón
- Department of Physiology, Biophysics and Neuroscience, Center for Research and Advanced Studies, Mexico City 07360, Mexico
| | - María Luisa Roldán
- Department of Physiology, Biophysics and Neuroscience, Center for Research and Advanced Studies, Mexico City 07360, Mexico
| | - Rodolfo Ocadiz-Delgado
- Department of Genetics and Molecular Biology, Center for Research and Advanced Studies, Mexico City 07360, Mexico
| | - Enoc Mariano Cortés-Malagón
- Research Unit on Genetics and Cancer, Research Division, Hospital Juárez de México, Mexico City 07760, Mexico
| | - Bibiana Chávez-Munguía
- Department of Infectomics and Molecular Pathogenesis, Center for Research and Advanced Studies, Mexico City 07360, Mexico
| | - Georgina Ramírez
- Department of Electrical Engineering, Center for Research and Advanced Studies, Mexico City 07360, Mexico
| | - René Asomoza
- Department of Electrical Engineering, Center for Research and Advanced Studies, Mexico City 07360, Mexico
| | - Liora Shoshani
- Department of Physiology, Biophysics and Neuroscience, Center for Research and Advanced Studies, Mexico City 07360, Mexico
| | - Patricio Gariglio
- Department of Genetics and Molecular Biology, Center for Research and Advanced Studies, Mexico City 07360, Mexico
| | - Lorenza González-Mariscal
- Department of Physiology, Biophysics and Neuroscience, Center for Research and Advanced Studies, Mexico City 07360, Mexico
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Kohmoto T, Masuda K, Shoda K, Takahashi R, Ujiro S, Tange S, Ichikawa D, Otsuji E, Imoto I. Claudin-6 is a single prognostic marker and functions as a tumor-promoting gene in a subgroup of intestinal type gastric cancer. Gastric Cancer 2020; 23:403-417. [PMID: 31654186 DOI: 10.1007/s10120-019-01014-x] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Accepted: 10/12/2019] [Indexed: 02/06/2023]
Abstract
BACKGROUND We aimed to identify novel tumor-promoting drivers highly expressed in gastric cancer (GC) that contribute to worsened prognosis in affected patients. METHODS Genes whose expression was increased and correlated with worse prognosis in GC were screened using datasets from the Cancer Genome Atlas and Gene Expression Omnibus. We examined Claudin-6 (CLDN6) immunoreactivity in GC tissues and the effect of CLDN6 on cellular functions in GC cell lines. The mechanisms underlying GC-promoting function of CLDN6 were also investigated. RESULTS CLDN6 was identified as a gene overexpressed in GC tumors as compared with adjacent non-tumorous tissues and whose increased expression was positively correlated with worse overall survival of GC patients, particularly those with Lauren's intestinal type GC, in data from multiple publicly available datasets. Additionally, membranous CLDN6 immunoreactivity detected in intestinal type GC tumors was correlated with worse overall survival. In CLDN6-expressing GC cells, silencing of CLDN6 inhibited cell proliferation and migration/invasion abilities, possibly via suppressing transcription of YAP1 and its downstream transcriptional targets at least in part. CONCLUSIONS This study identified CLDN6 as a GC-promoting gene, suggesting that CLDN6 to be a possible single prognostic marker and promising therapeutic target for a subset of GC patients.
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Affiliation(s)
- Tomohiro Kohmoto
- Department of Human Genetics, Graduate School of Biomedical Sciences, Tokushima University, Tokushima, Tokushima, 770-8503, Japan.,Division of Molecular Genetics, Aichi Cancer Center Research Institute, 1-1 Kanokoden Chikusa-ku, Nagoya, Aichi, 464-8681, Japan
| | - Kiyoshi Masuda
- Kawasaki Medical School, Kurashiki, Okayama, 701-0192, Japan
| | - Katsutoshi Shoda
- Division of Digestive Surgery, Department of Surgery, Kyoto Prefectural University of Medicine, Kyoto, Kyoto, 602-8566, Japan
| | - Rizu Takahashi
- Department of Human Genetics, Graduate School of Biomedical Sciences, Tokushima University, Tokushima, Tokushima, 770-8503, Japan
| | - Sae Ujiro
- Department of Human Genetics, Graduate School of Biomedical Sciences, Tokushima University, Tokushima, Tokushima, 770-8503, Japan
| | - Shoichiro Tange
- Department of Human Genetics, Graduate School of Biomedical Sciences, Tokushima University, Tokushima, Tokushima, 770-8503, Japan
| | - Daisuke Ichikawa
- First Department of Surgery, Faculty of Medicine, University of Yamanashi, Chuo, Yamanashi, 409-3898, Japan
| | - Eigo Otsuji
- Division of Digestive Surgery, Department of Surgery, Kyoto Prefectural University of Medicine, Kyoto, Kyoto, 602-8566, Japan
| | - Issei Imoto
- Department of Human Genetics, Graduate School of Biomedical Sciences, Tokushima University, Tokushima, Tokushima, 770-8503, Japan. .,Division of Molecular Genetics, Aichi Cancer Center Research Institute, 1-1 Kanokoden Chikusa-ku, Nagoya, Aichi, 464-8681, Japan. .,Department of Cancer Genetics, Nagoya University Graduate School of Medicine, Nagoya, Aichi, 466-8550, Japan.
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Cao X, He GZ. Knockdown of CLDN6 inhibits cell proliferation and migration via PI3K/AKT/mTOR signaling pathway in endometrial carcinoma cell line HEC-1-B. Onco Targets Ther 2018; 11:6351-6360. [PMID: 30319275 PMCID: PMC6171518 DOI: 10.2147/ott.s174618] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
BACKGROUD Dysregulation of claudin-6 (CLDN6) expression in cancers has been widely documented. However, no study has reported a complete mechanistic understanding of CLDN6 regulation and function in endometrial carcinoma (EC) progression. In the current study, we aimed to assess the expression and biological functions of CLDN6 in EC. METHODS Firstly, the expression level of CLDN6 in EC was measured based on The Cancer Genome Atlas (TCGA) database. Then, qRT-PCR and western blotting were implemented to detect the expression levels of CLDN6 in 82 pairs of EC tissues and corresponding non-tumor tissues, as well as EC cell line HEC-1B. After knockdown of CLDN6, with the attempt to assess whether CLDN6 reduction had positive effects on the cell proliferation, clone formation, invasion and migration abilities of HLC-1Bs, cell counting kit-8 (CCK-8) assay (24, 48, 72 and 96 hours post-transfection), clone experiment, and invasion and migration assays were conducted. Through western blotting analysis, CLDN6-mediated phosphatidylinositol 3-kinase (PI3K) pathway was evaluated. RESULTS Based on the data of TCGA database, clinical patients and cell line HEC-1B, CLDN6 was up-regulated in EC compared with normal. Univariate as well as multivariate COX analysis indicated that CLDN6 expression can act as an independent prognostic factor for overall survival of EC. Further, knockdown of CLDN6 significantly inhibited HEC-1B cell proliferation, suppressed the colony numbers of HEC-1-B cells, and restrained the invasive and migratory ability of HEC-1-B cells. Importantly, through western blot analysis, we found that inhibition of CLDN6 remarkably decreased p-AKT, p-PI3K, and mTOR expression level in EC HEC-1B cell line. CONCLUSION Our data underscore the significance of CLDN6 in EC progression, and CLDN6 is a new candidate oncogene in EC. Our findings propose that targeting CLDN6 might offer future clinical utility in EC.
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Affiliation(s)
- Xia Cao
- Department of Gynaecology, Danyang People's Hospital of Jiangsu Province, Danyang 212300, Jiangsu Province, China,
| | - Guo-Zhao He
- Department of Gynaecology, Danyang People's Hospital of Jiangsu Province, Danyang 212300, Jiangsu Province, China,
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15
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Atypical teratoid/rhabdoid tumours: clinicopathological characteristics, prognostic factors and outcomes of 22 children from 2010 to 2015 in China. Pathology 2016; 48:555-63. [PMID: 27558890 DOI: 10.1016/j.pathol.2016.05.010] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2015] [Revised: 05/08/2016] [Accepted: 05/20/2016] [Indexed: 12/15/2022]
Abstract
Atypical teratoid/rhabdoid tumours (AT/RTs) are rare, highly malignant tumours of the central nervous system (CNS) with poor prognosis that usually affect young children. The aim of this study was to assess the clinicopathological features and prognostic factors of AT/RTs. Here, we describe the clinicopathological and immunohistochemical characteristics, along with the treatments and outcomes, of 22 patients with AT/RTs treated in our hospital from 2010 to 2015. Morphologically, cytoplasmic vacuoles, the most common characteristic in our cases, were observed in 68% of the cases. Similarly, vesicular nuclei were detected in 68% of the cases. However, rhabdoid cells were found in only 59.1% of the cases and were not observed in 40.9% of the cases. Immunohistochemical analysis revealed loss of nuclear INI1 expression in all 22 cases. Age, surgical resection and adjuvant therapy, but not tumour location, were associated with AT/RTs patient prognosis. Our results showed that cells with cytoplasmic vacuoles or with vesicular nuclei are more common than rhabdoid cells in patients with AT/RTs and that a lack of INI1 protein expression is the most useful marker for the differential diagnosis of AT/RTs. Young age is a negative prognostic factor, whereas gross total surgical resection and adjuvant therapy are positive prognostic factors for AT/RT patients.
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16
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Stadler CR, Bähr-Mahmud H, Plum LM, Schmoldt K, Kölsch AC, Türeci Ö, Sahin U. Characterization of the first-in-class T-cell-engaging bispecific single-chain antibody for targeted immunotherapy of solid tumors expressing the oncofetal protein claudin 6. Oncoimmunology 2015; 5:e1091555. [PMID: 27141353 PMCID: PMC4839326 DOI: 10.1080/2162402x.2015.1091555] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2015] [Revised: 09/02/2015] [Accepted: 09/03/2015] [Indexed: 01/18/2023] Open
Abstract
The fetal tight junction molecule claudin 6 (CLDN6) is virtually absent from any normal tissue, whereas it is aberrantly and frequently expressed in various cancers of high medical need. We engineered 6PHU3, a T-cell-engaging bispecific single chain molecule (bi-(scFv)2) with anti-CD3/anti-CLDN6 specificities, and characterized its pharmacodynamic properties. Our data show that upon engagement by 6PHU3, T cells strongly upregulate cytotoxicity and activation markers, proliferate and acquire an effector phenotype. 6PHU3 exerts potent killing of cancer cells in vitro with EC50 values in the pg/mL range. Subcutaneous xenograft tumors in NSG mice engrafted with human PBMCs are eradicated by 6PHU3 treatment and survival of mice is significantly prolonged. Tumors of 6PHU3-treated mice are strongly infiltrated with activated CD4+, CD8+ T cells and TEM type cells but not Tregs and display a general activation of a mostly inflammatory phenotype. These effects are only observed upon bispecific but not monospecific engagement of 6PHU3. Together with the exceptionally cancer cell selective expression of the oncofetal tumor marker CLDN6, this provides a safeguard with regard to toxicity. In summary, our data shows that the concept of T-cell redirection combined with that of highly selective targeting of CLDN6-positive solid tumors is effective. Thus, exploring 6PHU3 for clinical therapy is warranted.
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Affiliation(s)
- Christiane R Stadler
- Biopharmaceutical New Technologies (BioNTech) AG, Mainz, Germany; TRON - Translational Oncology at the University Medical Center of the Johannes Gutenberg University gGmbH, Mainz, Germany
| | - Hayat Bähr-Mahmud
- Biopharmaceutical New Technologies (BioNTech) AG, Mainz, Germany; TRON - Translational Oncology at the University Medical Center of the Johannes Gutenberg University gGmbH, Mainz, Germany
| | - Laura M Plum
- Biopharmaceutical New Technologies (BioNTech) AG, Mainz, Germany; TRON - Translational Oncology at the University Medical Center of the Johannes Gutenberg University gGmbH, Mainz, Germany
| | - Kathrin Schmoldt
- Biopharmaceutical New Technologies (BioNTech) AG, Mainz, Germany; TRON - Translational Oncology at the University Medical Center of the Johannes Gutenberg University gGmbH, Mainz, Germany
| | - Anne C Kölsch
- TRON - Translational Oncology at the University Medical Center of the Johannes Gutenberg University gGmbH , Mainz, Germany
| | | | - Ugur Sahin
- Biopharmaceutical New Technologies (BioNTech) AG, Mainz, Germany; TRON - Translational Oncology at the University Medical Center of the Johannes Gutenberg University gGmbH, Mainz, Germany; Department for Internal Medicine, Johannes Gutenberg University, III; Mainz, Germany
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17
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Wang Q, Zhang Y, Zhang T, Han ZG, Shan L. Low claudin-6 expression correlates with poor prognosis in patients with non-small cell lung cancer. Onco Targets Ther 2015; 8:1971-7. [PMID: 26261421 PMCID: PMC4527519 DOI: 10.2147/ott.s85478] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Objective Claudins are found in junctional complexes mediating cell adhesion and are involved in the attachment of tight junctions to the underlying cytoskeleton. Abnormal claudin-6 expression has been observed for a variety of malignant solid tumors, but the expression of claudin-6 in non-small cell lung cancer (NSCLC) has not yet been characterized. Methods Immunohistochemistry, reverse transcription-polymerase chain reaction (RT-PCR), and western blot analysis were used to quantify claudin-6 expression in 123 cases of NSCLC and non-cancerous adjacent tissue. We analyzed the relationship between claudin-6 expression and clinicopathological features of NSCLC. The Kaplan–Meier method was used to analyze postoperative survival rates, and the log-rank test was used to assess differences in survival rates. The Cox regression model was used to perform multivariate analysis. Results Claudin-6 expression was low for 61 of 123 (49.6%) NSCLC tissue samples and for 33 of 123 (26.8%) normal adjacent tissue samples. RT-PCR and western blot analyses confirmed the immunohistochemistry results. Claudin-6 expression was associated with lymph node metastasis (P<0.001) and TNM stage (P=0.007). Kaplan–Meier analysis indicated that patients with low claudin-6 expression had significantly lower survival rates than those with high claudin-6 expression. Multivariate analysis suggested that low claudin-6 expression was an independent indicator of prognosis in NSCLC patients. Conclusion Low claudin-6 expression is an independent prognostic biomarker that indicates a worse prognosis in patients with NSCLC.
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Affiliation(s)
- Qiang Wang
- Department of Thoracic Oncology, The Affiliated Tumor Hospital of Xinjiang Medical University, Urumqi, Xinjiang Province, People's Republic of China
| | - Yan Zhang
- Department of Thoracic Oncology, The Affiliated Tumor Hospital of Xinjiang Medical University, Urumqi, Xinjiang Province, People's Republic of China
| | - Tao Zhang
- Department of Oncology, First Hospital of Lanzhou University, Lanzhou, Gansu Province, People's Republic of China
| | - Zhi-Gang Han
- Department of Thoracic Oncology, The Affiliated Tumor Hospital of Xinjiang Medical University, Urumqi, Xinjiang Province, People's Republic of China
| | - Li Shan
- Department of Thoracic Oncology, The Affiliated Tumor Hospital of Xinjiang Medical University, Urumqi, Xinjiang Province, People's Republic of China
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Clostridium perfringens enterotoxin (CPE) and CPE-binding domain (c-CPE) for the detection and treatment of gynecologic cancers. Toxins (Basel) 2015; 7:1116-25. [PMID: 25835384 PMCID: PMC4417958 DOI: 10.3390/toxins7041116] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2015] [Revised: 03/17/2015] [Accepted: 03/23/2015] [Indexed: 12/24/2022] Open
Abstract
Clostridium perfringens enterotoxin (CPE) is a three-domain polypeptide, which binds to Claudin-3 and Claudin-4 with high affinity. Because these receptors are highly differentially expressed in many human tumors, claudin-3 and claudin-4 may provide an efficient molecular tool to specifically identify and target biologically aggressive human cancer cells for CPE-specific binding and cytolysis. In this review we will discuss these surface proteins as targets for the detection and treatment of chemotherapy-resistant gynecologic malignancies overexpressing claudin-3 and -4 using CPE-based theranostic agents. We will also discuss the use of fluorescent c-CPE peptide in the operative setting for real time detection of micro-metastatic tumors during surgery and review the potential role of CPE in other medical applications.
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Tight junction protein claudin-6 inhibits growth and induces the apoptosis of cervical carcinoma cells in vitro and in vivo. Med Oncol 2015; 32:148. [PMID: 25822939 DOI: 10.1007/s12032-015-0600-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2015] [Accepted: 03/24/2015] [Indexed: 01/15/2023]
Abstract
Claudin-6, a member of claudin family integral membrane proteins, has recently been reported to be a tumor suppressor for breast cancer. However, whether it plays a role in other types of cancer remains unclear. In the present study, we showed that the expression of claudin-6 is down-regulated in cervical carcinoma tissues as revealed by immunohistochemistry. Through over-expressing claudin-6 in HeLa and C33A cervical carcinoma cells, we found that claudin-6 is localized at plasma membrane and it increases transepithelial electrical resistance of the cells. Gain of claudin-6 expression suppresses cell proliferation, colony formation in vitro, and tumor growth in vivo. The effects are accompanied and potentially caused by promotion of tumor cell apoptosis. Taken together, these results suggest that claudin-6 may function as a tumor suppressor and loss of claudin-6 contributes to enhanced tumorigenic properties of cervical carcinoma cells.
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Heerma van Voss MR, van Diest PJ, Smolders YHCM, Bart J, van der Wall E, van der Groep P. Distinct claudin expression characterizes BRCA1-related breast cancer. Histopathology 2014; 65:814-27. [PMID: 25041042 DOI: 10.1111/his.12490] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2014] [Accepted: 07/01/2014] [Indexed: 01/05/2023]
Abstract
AIMS Members of the claudin family are involved in cancer progression and are differentially expressed in subtypes of breast cancer. Breast cancers in BRCA1 germ line mutation carriers have distinct clinicopathological characteristics. Biomarkers that discriminate between BRCA1-related and sporadic breast cancer cases are needed to improve early identification of mutation carriers. In this study we evaluated protein expression of five major claudins in BRCA1-related breast cancers in comparison with sporadic controls. METHODS AND RESULTS Forty breast cancers in BRCA1 mutation carriers and 40 age-matched sporadic breast cancers were immunohistochemically stained for claudins 1, 3, 4, 6 and 7. Total intratumoural expression levels were compared to those in the surrounding normal tissue. In addition, subcellular claudin expression was scored. Higher overexpression rates were observed for all five claudins in BRCA1-related breast cancers when compared to sporadic controls. In multivariate analysis, overexpression of claudin 3, 4, and 7 was mainly dependent on ER-status, whereas overexpression of claudin 6 and high membranous expression of claudin 1 were independent of other characteristics. CONCLUSIONS BRCA1-related breast cancers are characterized by frequent overexpression of claudins. Especially claudin 1 and 6 expression may help to discriminate mutation carriers from sporadic breast cancer cases.
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21
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Neuwelt AJ, Nguyen T, Wu YJ, Donson AM, Vibhakar R, Venkatamaran S, Amani V, Neuwelt EA, Rapkin LB, Foreman NK. Preclinical high-dose acetaminophen with N-acetylcysteine rescue enhances the efficacy of cisplatin chemotherapy in atypical teratoid rhabdoid tumors. Pediatr Blood Cancer 2014; 61:120-7. [PMID: 23956023 PMCID: PMC5131918 DOI: 10.1002/pbc.24602] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/21/2012] [Accepted: 04/24/2013] [Indexed: 02/06/2023]
Abstract
BACKGROUND Atypical teratoid rhabdoid tumors (AT-RT) are pediatric tumors of the central nervous system with limited treatment options and poor survival rate. We investigated whether enhancing chemotherapy toxicity by depleting intracellular glutathione (GSH; a key molecule in cisplatin resistance) with high dose acetaminophen (AAP), may improve therapeutic efficacy in AT-RT in vitro. PROCEDURE BT16 (cisplatin-resistant) and BT12 (cisplatin-sensitive) AT-RT cell lines were treated with combinations of AAP, cisplatin, and the anti-oxidant N-acetylcysteine (NAC). Cell viability, GSH and peroxide concentrations, mitochondrial damage, and apoptosis were evaluated in vitro. RESULTS AAP enhanced cisplatin cytotoxicity in cisplatin-resistant BT16 cells but not cisplatin-sensitive BT12 cells. Baseline GSH levels were elevated in BT16 cells compared to BT12 cells, and AAP decreased GSH to a greater magnitude in BT16 cells than BT12 cells. Unlike BT12 cells, BT16 cells did not have elevated peroxide levels upon treatment with cisplatin alone, but did have elevated levels when treated with AAP + cisplatin. Both cell lines had markedly increased mitochondrial injury when treated with AAP + cisplatin relative to either drug treatment alone. The enhanced toxic effects were partially reversed with concurrent administration of NAC. CONCLUSIONS Our results suggest that AAP could be used as a chemo-enhancement agent to potentiate cisplatin chemotherapeutic efficacy particularly in cisplatin-resistant AT-RT tumors with high GSH levels in clinical settings.
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Affiliation(s)
| | - Tam Nguyen
- University of Colorado, Aurora, Colorado
| | - Y. Jeffrey Wu
- Oregon Health and Science University, Portland, Oregon
| | | | | | | | | | - Edward A. Neuwelt
- Oregon Health and Science University, Portland, Oregon,Department of Veterans Affairs Medical Center, Portland, Oregon
| | - Louis B. Rapkin
- Emory University and Children’s Healthcare of Atlanta, Atlanta, Georgia
| | - Nicholas K. Foreman
- Children’s Hospital Colorado, Aurora, Colorado,Correspondence to: Nicholas K. Foreman, 1056 East 19th Avenue B115, Denver, CO 80218.
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Kwon MJ. Emerging roles of claudins in human cancer. Int J Mol Sci 2013; 14:18148-80. [PMID: 24009024 PMCID: PMC3794774 DOI: 10.3390/ijms140918148] [Citation(s) in RCA: 149] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2013] [Revised: 08/23/2013] [Accepted: 08/27/2013] [Indexed: 02/07/2023] Open
Abstract
Claudins are major integral membrane proteins of tight junctions. Altered expression of several claudin proteins, in particular claudin-1, -3, -4 and -7, has been linked to the development of various cancers. Although their dysregulation in cancer suggests that claudins play a role in tumorigenesis, the exact underlying mechanism remains unclear. The involvement of claudins in tumor progression was suggested by their important role in the migration, invasion and metastasis of cancer cells in a tissue-dependent manner. Recent studies have shown that they play a role in epithelial to mesenchymal transition (EMT), the formation of cancer stem cells or tumor-initiating cells (CSCs/TICs), and chemoresistance, suggesting that claudins are promising targets for the treatment of chemoresistant and recurrent tumors. A recently identified claudin-low breast cancer subtype that is characterized by the enrichment of EMT and stem cell-like features is significantly associated with disease recurrence, underscoring the importance of claudins as predictors of tumor recurrence. The critical role of epigenetic mechanisms in the regulation of claudin expression indicates the possible application of epigenetic therapy to target claudins. A better understanding of the emerging role of claudins in CSC/TICs and chemoresistance may help to develop therapies against recurrent cancers.
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Affiliation(s)
- Mi Jeong Kwon
- College of Pharmacy, Kyungpook National University, 80 Daehak-ro, Buk-gu, Daegu 702-701, Korea.
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Chan ES, Pawel BR, Corao DA, Venneti S, Russo P, Santi M, Sullivan LM. Immunohistochemical expression of glypican-3 in pediatric tumors: an analysis of 414 cases. Pediatr Dev Pathol 2013; 16:272-7. [PMID: 23530909 DOI: 10.2350/12-06-1216-oa.1] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Glypican-3 (GPC3) is a proteoglycan thought to play an important role during development. Germline GPC3 mutations are seen in the rare Simpson-Golabi-Behmel syndrome (SGBS), which predisposes patients to Wilms tumor, hepatoblastoma, and neuroblastoma. While numerous adult tumors have been evaluated by immunohistochemistry for GPC3, no comprehensive assessment has been done in pediatric tumors. We therefore investigated GPC3 expression in 143 pediatric central nervous system (CNS) tumors and 271 non-CNS tumors. Among non-CNS tumors, GPC3 expression was seen in 9/9 (100%) hepatoblastomas, 4/6 (67%) malignant rhabdoid tumors, 5/13 (38%) Wilms tumors, 11/37 (30%) alveolar rhabdomyosarcomas, and 8/45 (18%) embryonal rhabdomyosarcomas. All 136 neuroblastomas, 14 Ewing sarcoma/primitive neuroectodermal tumors, and 11 synovial sarcomas were immunonegative for GPC3. Among CNS tumors, GPC3 had restricted expression, with positivity in 6/6 (100%) atypical teratoid rhabdoid tumors and 1/4 (25%) craniopharyngiomas. The remaining 136 CNS tumors-23 medulloblastomas, 21 pilocytic astrocytomas, 13 gangliogliomas, 12 ependymomas, 12 glioblastomas, 11 choroid plexus neoplasms, 10 diffuse astrocytomas (grade II/III), 10 meningiomas, 8 dysembryoplastic neuroepithelial tumors, 8 oligodendrogliomas, 3 craniopharyngiomas, 3 germinomas, and 2 neurocytomas-were entirely negative for GPC3. These results showed GPC3 positivity in a number of non-CNS tumors, with no consistent discrimination between tumors that were or were not associated with SGBS. Within the CNS, GPC3 positivity was limited to a small subset of CNS neoplasms and may thus serve as a useful positive diagnostic biomarker (P < 0.0001) in addition to negative INI1/BAF47/SMARCB1 staining to differentiate atypical teratoid rhabdoid tumors from other high-grade pediatric brain tumors.
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Affiliation(s)
- Elaine S Chan
- Department of Pathology and Laboratory Medicine, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
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English DP, Santin AD. Claudins overexpression in ovarian cancer: potential targets for Clostridium Perfringens Enterotoxin (CPE) based diagnosis and therapy. Int J Mol Sci 2013; 14:10412-37. [PMID: 23685873 PMCID: PMC3676847 DOI: 10.3390/ijms140510412] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2013] [Revised: 04/26/2013] [Accepted: 04/27/2013] [Indexed: 02/06/2023] Open
Abstract
Claudins are a family of tight junction proteins regulating paracellular permeability and cell polarity with different patterns of expression in benign and malignant human tissues. There are approximately 27 members of the claudin family identified to date with varying cell and tissue-specific expression. Claudins-3, -4 and -7 represent the most highly differentially expressed claudins in ovarian cancer. While their exact role in ovarian tumors is still being elucidated, these proteins are thought to be critical for ovarian cancer cell invasion/dissemination and resistance to chemotherapy. Claudin-3 and claudin-4 are the natural receptors for the Clostridium perfringens enterotoxin (CPE), a potent cytolytic toxin. These surface proteins may therefore represent attractive targets for the detection and treatment of chemotherapy-resistant ovarian cancer and other aggressive solid tumors overexpressing claudin-3 and -4 using CPE-based theranostic agents.
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Affiliation(s)
- Diana P. English
- Department of Obstetrics, Gynecology and Reproductive Sciences, Yale University School of Medicine, New Haven, CT 06520, USA; E-Mail:
| | - Alessandro D. Santin
- Department of Obstetrics, Gynecology and Reproductive Sciences, Yale University School of Medicine, New Haven, CT 06520, USA; E-Mail:
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Abstract
Central nervous system tumors are the most frequent malignant tumor in children and the main cause of death in this age group after traffic accidents. The current estimates are that one adult in 2500 is a survivor of a brain tumor that occurred during childhood. These tumors are particularly heterogeneous in terms of histology/biology, treatment, and outcome. They share, however, a high risk of neurological and cognitive morbidity due to the disease itself and the treatment modalities (radiotherapy, surgery, and chemotherapy). Diagnosis is frequently delayed because symptoms are usually nonspecific at the beginning of the evolution. Posterior fossa is the most frequent site and the tumors present most frequently with signs of intracranial hypertension. Supratentorial tumors are more frequent in infants and in adolescents; seizures are not uncommon, especially for benign tumors. When adjuvant treatment is needed, radiotherapy is usually the mainstay apart from some histologies where chemotherapy may be sufficient: low-grade gliomas, desmoplastic medulloblastomas, malignant glial tumors in infants. Multidisciplinary care is best performed in tertiary care centers and should include early rehabilitation programs soon after surgery.
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Affiliation(s)
- Grill Jacques
- Brain Tumor Program, Department of Pediatric and Adolescent Oncology, Gustave Roussy Cancer Institute, Villejuif, France.
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26
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Regulation of Tight Junctions for Therapeutic Advantages. CANCER METASTASIS - BIOLOGY AND TREATMENT 2013. [DOI: 10.1007/978-94-007-6028-8_9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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27
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Lal-Nag M, Battis M, Santin AD, Morin PJ. Claudin-6: a novel receptor for CPE-mediated cytotoxicity in ovarian cancer. Oncogenesis 2012; 1:e33. [PMID: 23552466 PMCID: PMC3511677 DOI: 10.1038/oncsis.2012.32] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Claudins are integral tight junction proteins that are responsible for maintaining the integrity of epithelial cell architecture and cell polarity. Claudin-3 and -4 are overexpressed in several cancers and have been shown to act as receptors for the Clostridium perfringens enterotoxin (CPE), a toxin that causes rapid cell lysis. CPE has demonstrated effectiveness in treating several different cancers in mouse models, provided that these cancers express claudin-3 or claudin-4. Here, we show that claudin-3/4 expression is not an absolute requirement for CPE action and, through overexpression and knockdown experiments, we identify claudin-6 as a novel functional receptor for CPE. Indeed, UCI-101, an ovarian cancer cell line highly sensitive to CPE, does not express claudin-3/4 and knockdown of claudin-6 in these cells decreases CPE sensitivity. Moreover, two different ovarian cell lines that are resistant to the effects of CPE can be made sensitive through claudin-6 overexpression. Binding assays show that CPE can indeed bind claudin-6 in cells and that this binding is associated with CPE cytotoxicity. Multicellular tumor spheroids experiments demonstrate that claudin-6 can also be a target of CPE in three-dimensional cultures. Our data establish claudin-6 as a novel receptor for CPE and introduces the possibility of a novel targeted therapeutic for ovarian and other cancers that express claudin-6.
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Affiliation(s)
- M Lal-Nag
- Laboratory of Molecular Biology and Immunology, National Institute on Aging, NIH, Biomedical Research Center, Baltimore MD, USA
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28
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Hasselblatt M, Isken S, Linge A, Eikmeier K, Jeibmann A, Oyen F, Nagel I, Richter J, Bartelheim K, Kordes U, Schneppenheim R, Frühwald M, Siebert R, Paulus W. High-resolution genomic analysis suggests the absence of recurrent genomic alterations other than SMARCB1 aberrations in atypical teratoid/rhabdoid tumors. Genes Chromosomes Cancer 2012; 52:185-90. [PMID: 23074045 DOI: 10.1002/gcc.22018] [Citation(s) in RCA: 119] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2012] [Accepted: 09/18/2012] [Indexed: 01/09/2023] Open
Abstract
Atypical teratoid/rhabdoid tumor (AT/RT) is a rare malignant pediatric brain tumor characterized by genetic alterations affecting the SMARCB1 (hSNF5/INI1) locus in chromosome band 22q11.2. To identify potential additional genetic alterations, high-resolution genome-wide analysis was performed using a molecular inversion probe single-nucleotide polymorphism (MIP SNP) assay (Affymetrix OncoScan formalin-fixed paraffin-embedded express) on DNA isolated from 18 formalin-fixed paraffin-embedded archival samples. Alterations affecting the SMARCB1 locus could be demonstrated by MIP SNP in 15 out of 16 evaluable cases (94%). These comprised five tumors with homozygous deletions, six tumors with heterozygous deletions, and four tumors with copy number neutral loss of heterozygosity (LOH) involving chromosome band 22q11.2. Remarkably, MIB SNP analysis did not yield any further recurrent chromosomal gains, losses, or copy neutral LOH. On MIP SNP screening for somatic mutations, the presence of a SMARCB1 mutation (c.472C>T p.R158X) was confirmed, but no recurrent mutations of other cancer relevant genes could be identified. Results of fluorescence in situ hybridization, multiplex ligation-dependent probe amplification, and SMARCB1 sequencing were highly congruent with that of the MIP SNP assay. In conclusion, these data further suggest the absence of recurrent genomic alterations other than SMARCB1 in AT/RT.
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Affiliation(s)
- Martin Hasselblatt
- Institute of Neuropathology, University Hospital Münster, Münster, Germany.
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29
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Ushiku T, Shinozaki-Ushiku A, Maeda D, Morita S, Fukayama M. Distinct expression pattern of claudin-6, a primitive phenotypic tight junction molecule, in germ cell tumours and visceral carcinomas. Histopathology 2012; 61:1043-56. [DOI: 10.1111/j.1365-2559.2012.04314.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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30
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Histopathologic and Ultrastructural Features and Claudin Expression in Papillary Tumors of the Pineal Region. Am J Surg Pathol 2012; 36:916-28. [DOI: 10.1097/pas.0b013e31824b7114] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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31
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Yao PL, Lin YC, Richburg JH. Mono-(2-ethylhexyl) phthalate (MEHP) promotes invasion and migration of human testicular embryonal carcinoma cells. Biol Reprod 2012; 86:160, 1-10. [PMID: 22321834 DOI: 10.1095/biolreprod.111.097295] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Testicular dysgenesis syndrome refers to a collection of diseases in men, including testicular cancer, that arise as a result of abnormal testicular development. Phthalates are a class of chemicals used widely in the production of plastic products and other consumer goods. Unfortunately, phthalate exposure has been linked to reproductive dysfunction and has been shown to adversely affect normal germ cell development. In this study, we show that mono-(2-ethylhexyl) phthalate (MEHP) induces matrix metalloproteinase 2 (MMP2) expression in testicular embryonal carcinoma NT2/D1 cells but has no significant effect on MMP9 expression. NT2/D1 cells also have higher levels of MYC expression following MEHP treatment. It is widely recognized that activation of MMP2 and MYC is tightly associated with tumor metastasis and tumor progression. Gelatin zymographic analysis indicates that MEHP strongly activates MMP2 in NT2/D1 cells. Addition of the MMP2-specific inhibitor SB-3CT inhibited MEHP-enhanced cell invasion and migration, demonstrating that MMP2 plays a functional role in promoting testicular embryonal carcinoma progression in response to MEHP exposure. Furthermore, we investigated genome-wide gene expression profiles of NT2/D1 cells following MEHP exposure at 0, 3, and 24 h. Microarray analysis and semiquantitative RT-PCR revealed that MEHP exposure primarily influenced genes in cell adhesion and transcription in NT2/D1 cells. Gap junction protein-alpha 1, vinculin, and inhibitor of DNA-binding protein-1 were significantly down-regulated by MEHP treatment, while claudin-6 and beta 1-catenin expression levels were up-regulated. This study provides insight into mechanisms that may account for modulating testicular cancer progression following phthalate exposure.
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Affiliation(s)
- Pei-Li Yao
- Center for Molecular and Cellular Toxicology, Division of Pharmacology and Toxicology, College of Pharmacy, The University of Texas at Austin, Austin, Texas, USA.
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32
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Nageswara Rao AA, Packer RJ. Impact of molecular biology studies on the understanding of brain tumors in childhood. Curr Oncol Rep 2012; 14:206-12. [PMID: 22237928 DOI: 10.1007/s11912-012-0214-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Pediatric brain tumors are the second most common form of childhood malignancy. Brain tumors are a very heterogenous group of tumors and the pathogenesis of many of these tumors is yet to be clearly elucidated. Current diagnostic tools include histopathology and immunohistochemistry, but classification based on these means has significant limitations. As our understanding of the molecular biology of individual tumors continues to increase it has led to the identification of reliable and increasingly available molecular biomarkers. Molecular techniques are likely to complement current standard means of investigation and help not only overcome diagnostic challenges but may also result in better disease classification and risk stratification, leading to more personalized therapeutic approaches.
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Affiliation(s)
- Amulya A Nageswara Rao
- Division of Pediatric Hematology/Oncology, Department of Pediatrics and Adolescent Medicine, Mayo Clinic, Rochester, MN 55905, USA.
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Fleming AJ, Hukin J, Rassekh R, Fryer C, Kim J, Stemmer-Rachamimov A, Birks DK, Huang A, Yip S, Dunham C. Atypical teratoid rhabdoid tumors (ATRTs): the British Columbia's Children's Hospital's experience, 1986-2006. Brain Pathol 2012; 22:625-35. [PMID: 22188464 DOI: 10.1111/j.1750-3639.2011.00561.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
As "atypical teratoid rhabdoid tumors" (ATRTs) may mimic "small round blue cell tumors" (SRBCT), we reexamined our ATRT experience focusing upon INI-1 immunohistochemistry (IHC). All high-grade pediatric brain tumors occurring from 1986-2006 at our institution underwent INI-1 IHC. Clinicopathologic data from each INI-1 immunonegative case were reviewed. Additional genetic, epigenetic and IHC analyses (including interrogation of INI-1 and CLDN6) were performed on a subset of the INI-1 immunonegative cases. Twelve INI-1 IHC negative tumors were identified retrospectively, of which only two previously carried the diagnosis of ATRT. Overall, the clinicopathologic and genetic data supported the assertion that all 12 cases represented ATRT. Unexpectedly, three long-term survivors (4.2, 7.0 and 8.5 years) were identified. As hypothesized, "teratoid" and "rhabdoid" histologic features were relatively infrequent despite gross total resections in some cases. Methylation specific polymer chain reaction (PCR) (MSP) revealed a uniform methylation pattern across all cases and gene promoters tested (ie, MGMT, HIC1, MLH3 and RASSF1); notably, all cases demonstrated unmethylated MGMT promoters. Our data demonstate that a primitive non-rhabdoid histophenotype is common among ATRTs and highlights the diagnostic importance of INI-1 IHC. Epigenetically, the MGMT promoter is usually unmethylated in ATRT, suggesting that potential temozolomide-based chemotherapy may be of limited efficacy.
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Affiliation(s)
- Adam J Fleming
- Division of Hematology, Oncology and Bone Marrow Transplantation, British Columbia Children's Hospital, Vancouver, British Columbia, Canada
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Abstract
Claudins are tight junction proteins with claudin-6 (CLDN6) expression mostly restricted to embryonic and fetal life. Previously reported gene expression microarray analysis showed an increased level of CLDN6 in atypical teratoid rhabdoid tumors (AT/RT) compared with other central nervous system (CNS) tumors and sarcomas. However, there exist conflicting data on expression of CLDN6 as assessed by immunohistochemistry in CNS tumors. We established membranous staining as a specific and reproducible method for evaluating CLDN6 expression based on fetal and adolescent controls. We then evaluated a large group (257) of pediatric tumors using tissue microarrays, including: 47 malignant rhabdoid tumors (MRTs), (31 AT/RTs and 16 non-CNS MRTs); 67 small, round, blue cell tumors (10 Wilms tumors, 10 embryonal rhabdomyosarcomas, 10 neuroblastomas (NBs), 10 synovial sarcomas (SSs), 9 hepatoblastomas (HBs), 9 alveolar rhabdomyosarcomas, and 9 Ewings sarcomas); and 143 CNS tumors (24 medulloblastomas, 21 pilocytic astrocytomas, 14 astrocytomas grade II/III, 13 gangliogliomas, 12 glioblastomas, 12 ependymal tumors, 11 choroid plexus tumors, 10 meningiomas, 8 dysembryoplastic neuroepithelial tumors, 8 oligodendrogliomas, 4 craniopharyngiomas, 2 germinomas, 2 primitive neuroectodermal tumors (PNET), and 2 central neurocytomas). CLDN6 expression was seen in 12 of 31 (39%) AT/RTs, 7 of 16 (44%) non-CNS MRTs, 5 of 10 (50%) Wilms tumors, 1 of 9 (11%) HBs, 2 of 2 (100%) germinomas, 1 of 2 (50%) CNS PNETs, 1 of 24 (4%) medulloblastomas, and 1 of 10 (10%) meningiomas. Ten of 11 (91%) choroid plexus tumors showed apical staining but no concentric membranous staining. Although CLDN6 is expressed in both AT/RTs and MRTs, it is not a specific biomarker as it is expressed in a variety of other pediatric CNS and soft tissue tumors.
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35
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Venkataraman S, Alimova I, Tello T, Harris PS, Knipstein JA, Donson AM, Foreman NK, Liu AK, Vibhakar R. Targeting Aurora Kinase A enhances radiation sensitivity of atypical teratoid rhabdoid tumor cells. J Neurooncol 2012; 107:517-26. [PMID: 22246202 DOI: 10.1007/s11060-011-0795-y] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2011] [Accepted: 12/27/2011] [Indexed: 10/14/2022]
Abstract
Atypical teratoid/rhabdoid tumors (ATRT) are rare, highly malignant, embryonal CNS tumors with a poor prognosis. Therapy relies on highly toxic chemotherapy and radiotherapy. To improve outcomes and decrease morbidity, more targeted therapy is required. Gene expression analysis revealed elevated expression of multiple kinases in ATRT tissues. Aurora Kinase A was one of the candidate kinases. The objective of this study was to evaluate the impact of Aurora Kinase A inhibition in ATRT cell lines. Our analysis revealed that inhibition of Aurora Kinase A induces cell death in ATRT cells and the small molecule inhibitor MLN 8237 sensitizes these cells to radiation. Furthermore, inhibition of Aurora Kinase A resulted in decreased activity of pro-proliferative signaling pathways. These data indicate that inhibition of Aurora Kinase A is a promising small molecule target for ATRT therapy.
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Affiliation(s)
- Sujatha Venkataraman
- Department of Pediatrics, Children's Hospital Colorado, University of Colorado School of Medicine, Anschutz Medical Campus, Aurora, CO, USA
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36
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Dufour C, Beaugrand A, Le Deley MC, Bourdeaut F, André N, Leblond P, Bertozzi AI, Frappaz D, Rialland X, Fouyssac F, Edan C, Grill J, Quidot M, Varlet P. Clinicopathologic prognostic factors in childhood atypical teratoid and rhabdoid tumor of the central nervous system: a multicenter study. Cancer 2011; 118:3812-21. [PMID: 22180295 DOI: 10.1002/cncr.26684] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2011] [Revised: 10/04/2011] [Accepted: 10/18/2011] [Indexed: 12/21/2022]
Abstract
BACKGROUND The objective of this study was to describe the clinical and pathologic features and to identify prognostic factors in patients with atypical teratoid/rhabdoid tumors (AT/RT) of the central nervous system (CNS). METHODS Patients aged <18 years with newly diagnosed CNS AT/RT who were treated in France between 1998 and 2008 were retrospectively identified. The study included all patients who had a diagnosis of AT/RT confirmed by pathologic review, including immunostaining for INI 1, tumor protein 53 (p53), β-catenin, claudin-6, and Ki-67 and analysis for SMARCB1/hSNF5/INI1 mutation. RESULTS Fifty-eight patients with confirmed AT/RT were eligible for the current analysis. The median age at diagnosis was 1.4 years (range, 14 days to 8.5 years). The site of the primary tumor was supratentorial in 26 patients, infratentorial in 28 patients and spinal in 4 patients. Loss of INI1 nuclear expression was observed in 49 of 50 evaluable tumors. Positive claudin-6 was observed in 37 of 42 assessed tumors and, in 12 of those tumors, the staining was strong and diffuse. Positive nuclear immunoreactivity for β-catenin was observed in 24 of 44 tumors, and P53 was overexpressed in 31 of 44 tumors. Primary adjuvant therapy included chemotherapy in 47 patients and radiotherapy in 16 patients. The median follow-up was 58 months (range, 9-125 months), and the median survival was 9 months. Multivariate analysis identified age <2 years (P = .01), metastasis at diagnosis (P = .03), and strong immunopositivity for claudin-6 (P = .03) as prognostic factors for the risk of death. CONCLUSIONS AT/RT tumors in children carry a dismal prognosis. Age <2 years, metastasis at diagnosis, and strong claudin-6 positivity appeared to be independent prognostic factors for outcome.
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Affiliation(s)
- Christelle Dufour
- Department of Pediatric and Adolescent Oncology, Gustave Roussy Institute, 114 rue Edouard Vaillant,Villejuif, France.
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37
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Birks DK, Donson AM, Patel PR, Dunham C, Muscat A, Algar EM, Ashley DM, Kleinschmidt-Demasters BK, Vibhakar R, Handler MH, Foreman NK. High expression of BMP pathway genes distinguishes a subset of atypical teratoid/rhabdoid tumors associated with shorter survival. Neuro Oncol 2011; 13:1296-307. [PMID: 21946044 DOI: 10.1093/neuonc/nor140] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Molecular profiling of tumors has proven to be a valuable tool for identification of prognostic and diagnostic subgroups in medulloblastomas, glioblastomas, and other cancers. However, the molecular landscape of atypical teratoid/rhabdoid tumors (AT/RTs) remains largely unexplored. To address this issue, we used microarrays to measure the gene expression profiles of 18 AT/RTs and performed unsupervised hierarchical clustering to determine molecularly similar subgroups. Four major subgroups (clusters) were identified. These did not conform to sex, tumor location, or presence of monosomy 22. Clusters showed distinct gene signatures and differences in enriched biological processes, including elevated expression of some genes associated with choroid plexus lineage in cluster 4. In addition, survival differed significantly by cluster, with shortest survival (mean, 4.7 months) in both clusters 3 and 4, compared with clusters 1 and 2 (mean, 28.1 months). Analysis showed that multiple bone morphogenetic protein (BMP) pathway genes were upregulated in the short survival clusters, with BMP4 showing the most significant upregulation (270-fold). Thus, high expression of BMP pathway genes was negatively associated with survival in this dataset. Our study indicates that molecular subgroups exist in AT/RTs and that molecular profiling of these comparatively rare tumors may be of diagnostic, prognostic, and therapeutic value.
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Affiliation(s)
- Diane K Birks
- University of Colorado, Denver-Anschutz Medical Campus, Department of Neurosurgery, Aurora, CO 80045, USA.
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Abstract
Embryonal brain tumors are a heterogeneous group of neoplasms united by the presence of poorly differentiated stem-like cells. Molecular details are increasingly being used to separate them into biologically and clinically meaningful groups. For medulloblastoma, integrated mRNA expression profiling and DNA analysis by a number of research groups defines 4-6 distinctive molecular variants. A subset with prominent Wnt activity is associated with good clinical outcomes and classic histology. Medulloblastomas showing a Hedgehog gene expression signature are frequently of the desmoplastic/nodular subtype. Interestingly, Hedgehog activity is found in tumors arising either in infants or older teenagers and adults. The association of clinically aggressive medulloblastoma with MYC expression, large cell/anaplastic change and high levels of photoreceptor differentiation transcripts has also been noted in several studies. Immunohistochemical analysis of just one or two genes per molecular medulloblastoma variant may be sufficient for accurate classification, and this would be of great practical utility if validated. Advances have also been made in the classification of central nervous system (CNS) Primitive Neuroectodermal Tumors (PNET), as several groups have identified an amplicon at chromosome 19q13.41-42, which appears to define a unique PNET subtype associated with prominent true rosettes, young age and very poor outcomes.
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Affiliation(s)
- Charles G Eberhart
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, Md 21205, USA.
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39
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Antonelli M, Hasselblatt M, Haberler C, Di Giannatale A, Garrè ML, Donofrio V, Lauriola L, Ridola V, Arcella A, Frühwald M, Giangaspero F. Claudin-6 is of limited sensitivity and specificity for the diagnosis of atypical teratoid/rhabdoid tumors. Brain Pathol 2011; 21:558-63. [PMID: 21261775 DOI: 10.1111/j.1750-3639.2011.00478.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Recent gene expression microarray analyses have indicated that claudin-6 is specifically expressed in atypical teratoid rhabdoid tumors (AT/RTs), suggesting a role as a positive diagnostic marker in addition to SMARCB1 (INI1) loss, which is encountered in the majority of AT/RTs. In order to investigate the potential of claudin-6 as a diagnostic marker, expression was investigated in 59 AT/RTs and 60 other primary central nervous system (CNS) tumors, including primitive neuroectodermal tumors, medulloblastomas, choroid plexus tumors, and both pediatric and adult low- and high-grade gliomas using immunohistochemistry. Claudin-6 was expressed in 17/59 AT/RTs (29%), but also in a variety of other primary CNS tumors, including 60% of medulloblastomas and 21% of malignant gliomas. Even though high staining scores (2+ or 3+) were more often encountered in AT/RTs (Chi-square 4.177; P=0.041), the overall frequency of claudin-6 staining was not significantly higher in AT/RTs as compared with the other tumors (17/59 vs. 16/60; Chi-square=0.328; P=0.567). In a subgroup of 43 AT/RT patients, of which follow-up data were available, claudin-6 expression did not show any correlation with survival. In conclusion, claudin-6 immunohistochemistry is of limited sensitivity and specificity for the diagnosis of AT/RT and does not correlate with clinical behavior.
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Affiliation(s)
- Manila Antonelli
- Department of Radiology, Oncology and Anatomic-pathology Sciences, Sapienza University, Rome, Italy
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40
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Toth G, Zraly CB, Thomson TL, Jones C, Lapetino S, Muraskas J, Zhang J, Dingwall AK. Congenital anomalies and rhabdoid tumor associated with 22q11 germline deletion and somatic inactivation of the SMARCB1 tumor suppressor. Genes Chromosomes Cancer 2011; 50:379-88. [PMID: 21412926 DOI: 10.1002/gcc.20862] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2010] [Accepted: 01/26/2011] [Indexed: 12/31/2022] Open
Abstract
The most common microdeletion in humans involves the 22q11 region. Congenital anomalies associated with 22q11 loss include cardiac and facial defects. Less frequent is the co-presentation of malignant rhabdoid tumors that are highly aggressive childhood malignancies typically found in renal or extra-renal soft tissues and central nervous system. A newborn patient presented with multiple congenital anomalies consistent with 22q11 deletion syndrome including cleft lip and palate, ear tags and ventricular septal defects co-presenting with an axillary rhabdoid tumor. Comparative genomic hybridization revealed a 2.8 Mb germline deletion in the 22q11.2 region containing genes required for normal fetal development and the SMARCB1 tumor suppressor gene. Analysis of tumor DNA revealed a somatic deletion of exon 7 in the second allele of SMARCB1. Expression of SMARCB1 was absent, while tumor markers including MYC, GFAP, and CLAUDIN-6 were upregulated. The presence of tandem oriented BCRL modules located within interspersed low copy repeat elements throughout the 22q11 distal region may predispose this area for microdeletions through nonalleleic homologous recombination.
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Affiliation(s)
- George Toth
- Stritch School of Medicine, Loyola University of Chicago, Maywood, IL 60153, USA
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Schittenhelm J, Nagel C, Meyermann R, Beschorner R. Atypical teratoid/rhabdoid tumors may show morphological and immunohistochemical features seen in choroid plexus tumors. Neuropathology 2011; 31:461-7. [DOI: 10.1111/j.1440-1789.2010.01189.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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Molecular diagnostics of CNS embryonal tumors. Acta Neuropathol 2010; 120:553-66. [PMID: 20882288 DOI: 10.1007/s00401-010-0751-5] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2010] [Revised: 09/20/2010] [Accepted: 09/22/2010] [Indexed: 12/18/2022]
Abstract
Tremendous progress has recently been made in both molecular subgrouping, and the establishment of prognostic biomarkers for embryonal brain tumors, particularly medulloblastoma. Several prognostic biomarkers that were initially identified in retrospective cohorts of medulloblastoma, including MYC and MYCN amplification, nuclear β-catenin accumulation, and chromosome 17 aberrations have now been validated in clinical trials. Moreover, molecular subgroups based on distinct transcriptome profiles have been consistently reported from various groups on different platforms demonstrating that the concept of distinct medulloblastoma subgroups is very robust. Well-described subgroups of medulloblastomas include tumors showing wingless signaling pathway (Wnt) activation, and another characterized by sonic hedgehog pathway activity. Two or more additional subgroups were consistently reported to contain the vast majority of high-risk tumors, including most tumors with metastatic disease at diagnosis and/or large cell/anaplastic histology. Several years ago, atypical teratoid rhabdoid tumor (AT/RT) was recognized as a separate entity based on its distinct biology and particularly aggressive clinical behavior. These tumors may occur supra or infratentorially and are usually found to have genetic alterations of SMARCB1 (INI1/hSNF5), a tumor suppressor gene located on chromosome 22q. Subsequent loss of SMARCB1 protein expression comprises a relatively specific and sensitive diagnostic marker for AT/RT. For CNS primitive neuroectodermal tumors (CNS PNETs), a consistent finding has been that they are molecularly distinct from medulloblastoma. Furthermore, a distinct fraction of CNS PNETs with particularly poor prognosis only occurring in young children was delineated, which was previously labeled ependymoblastoma or embryonal tumor with abundant neuropil and true rosettes (ETANTR) and which is morphologically characterized by the presence of multilayered "ependymoblastic" rosettes. This group of tumors shows a unique cytogenetic abnormality not seen in other brain tumors: focal amplification of a micro-RNA cluster at chromosome 19q13.42, which has never been found to be amplified in other CNS PNETs, medulloblastoma or AT/RT. In summary, these consistent findings have significantly contributed to our ability to sub-classify embryonal brain tumors into clinically and biologically meaningful strata and, for some of the subgroups, have led to the identification of specific targets for future development of molecularly targeted therapies.
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Dunham C. Pediatric brain tumors: a histologic and genetic update on commonly encountered entities. Semin Diagn Pathol 2010; 27:147-59. [DOI: 10.1053/j.semdp.2010.04.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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El-Sheikh A, Fan R, Birks D, Donson A, Foreman NK, Vibhakar R. Inhibition of Aurora Kinase A enhances chemosensitivity of medulloblastoma cell lines. Pediatr Blood Cancer 2010; 55:35-41. [PMID: 20232424 DOI: 10.1002/pbc.22465] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
BACKGROUND Medulloblastoma comprises approximately 20% of all primary pediatric brain tumors. Despite recent advances, the survival rate for high-risk patients and the morbidity associated with these treatments remains suboptimal. To improve outcomes and decrease morbidity, more targeted therapy is required. One possible target is the Aurora Kinase family. The objective of this study was to evaluate the impact of Aurora Kinase A inhibition in medulloblastoma cell lines. PROCEDURE Cell proliferation was measured using an MTS assay after adding an Aurora Kinase inhibitor (C1368) at different concentrations. Cell cycle analysis was carried out by Flow Cytometry using propidium iodide (PI). RNAi experiments were performed using siRNA oligonucleotides. Luciferase experiments were carried out using the Cignal Finder 10 Pathway Reporter Arrays. RESULTS Inhibition of Aurora Kinase A induces cell death in medulloblastoma cells and lowers the IC(50) of other chemotherapeutic agents (etoposide and cisplatin) used in medulloblastoma treatment. Cell arrest at G2/M phase was significantly increased in medulloblastoma cell lines treated with C1368 Sigma at IC(30) or transfected siRNA. Inhibition of Aurora Kinase A resulted in decreased activity of pro-proliferative signaling pathways including Wnt, Myc, and RB as measured by luciferase reporter assays. CONCLUSIONS These data indicate that inhibition of Aurora Kinase A inhibits cell growth in medulloblastoma through inhibition of pro-proliferative signaling pathways Wnt, Myc, and RB. Additionally, combining Aurora Kinase A inhibition with other chemotherapeutic agents significantly lowers their IC(50), which make it a promising small molecule target for medulloblastoma therapy.
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