1
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Mansoor A, Akhter A, Shabani-Rad MT, Deschenes J, Yilmaz A, Trpkov K, Stewart D. Primary testicular lymphoma demonstrates overexpression of the Wilms tumor 1 gene and different mRNA and miRNA expression profiles compared to nodal diffuse large B-cell lymphoma. Hematol Oncol 2023; 41:828-837. [PMID: 37291944 DOI: 10.1002/hon.3190] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 04/30/2023] [Accepted: 05/19/2023] [Indexed: 06/10/2023]
Abstract
Diffuse large B-cell lymphoma (DLBCL) shows a high degree of clinical and biological heterogeneity. Primary testicular lymphoma (PTL) is an extranodal variant of DLBCL associated with a higher risk of recurrence, including contralateral testicles and central nervous system sanctuary sites. Several molecular aberrations, including somatic mutation of MYD88, CD79B, and upregulation of NF-kB, PDL-1, and PDL-2, are thought to contribute to the pathogenesis and poor prognosis of PTL. However, additional biomarkers are needed that may improve the prognosis and help understand the PTL biology and lead to new therapeutic targets. RNA from diagnostic tissue biopsies of the PTL-ABC subtype and matched nodal DLBCL-ABC subtype patients was evaluated by mRNA and miRNA expression. Screening of 730 essential oncogenic genes was performed, and their epigenetic connections were examined using the nCounter PAN-cancer pathway, and Human miRNA assays with the nCounter System (NanoString Technologies). PTL and nodal DLBCL patients were comparable in age, gender, and putative cell of origin (p > 0.05). Wilms tumor 1 (WT1) expression in PTL exceeded that in nodal DLBCL (>6-fold; p = 0.01, FDR <0.01) and WT1 associated pathway genes THBS4, PTPN5, PLA2G2A, and IFNA17 were upregulated in PTL (>2.0-fold, p < 0.01, FDR <0.01). Additionally, miRNAs targeting WT1 (hsa15a-5p, hsa-miR-16-5p, has-miR-361-5p, has-miR-27b-3p, has-miR-199a-5p, has-miR-199b-5p, has-miR-132-3p, and hsa-miR-128-3p) showed higher expression in PTL compared to nodal DLBCL (≥2.0-fold; FDR 0.01). Lower expression of BMP7, LAMB3, GAS1, MMP7, and LAMC2 (>2.0-fold, p < 0.01) was observed in PTL compared to nodal DLBCL. This research revealed higher WT1 expression in PTL relative to nodal DLBCL, suggesting that a specific miRNA subset may target WT1 expression and impact the PI3k/Akt pathway in PTL. Further investigation is needed to explore WT1's biological role in PTL and its potential as a therapeutic target.
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Affiliation(s)
- Adnan Mansoor
- Department of Pathology & Laboratory Medicine, University of Calgary and Alberta Precision Laboratories (APL), Calgary, Alberta, Canada
| | - Ariz Akhter
- Department of Pathology & Laboratory Medicine, University of Calgary and Alberta Precision Laboratories (APL), Calgary, Alberta, Canada
| | - Meer-Taher Shabani-Rad
- Department of Pathology & Laboratory Medicine, University of Calgary and Alberta Precision Laboratories (APL), Calgary, Alberta, Canada
| | - Jean Deschenes
- Department of Laboratory Medicine & Pathology, University of Alberta, Cross Cancer Institute and Alberta Precision Laboratories (APL), Calgary, Alberta, Canada
| | - Asli Yilmaz
- Department of Pathology & Laboratory Medicine, University of Calgary and Alberta Precision Laboratories (APL), Calgary, Alberta, Canada
| | - Kiril Trpkov
- Department of Pathology & Laboratory Medicine, University of Calgary and Alberta Precision Laboratories (APL), Calgary, Alberta, Canada
| | - Douglas Stewart
- Department of Oncology, University of Calgary, Tom Baker Cancer Centre, Calgary, Alberta, Canada
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2
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Pandey S, Raut KK, Clark AM, Baudin A, Djemri L, Libich DS, Ponniah K, Pascal SM. Enhancing the Conformational Stability of the cl-Par-4 Tumor Suppressor via Site-Directed Mutagenesis. Biomolecules 2023; 13:biom13040667. [PMID: 37189414 DOI: 10.3390/biom13040667] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Revised: 03/28/2023] [Accepted: 04/05/2023] [Indexed: 05/17/2023] Open
Abstract
Intrinsically disordered proteins play important roles in cell signaling, and dysregulation of these proteins is associated with several diseases. Prostate apoptosis response-4 (Par-4), an approximately 40 kilodalton proapoptotic tumor suppressor, is a predominantly intrinsically disordered protein whose downregulation has been observed in various cancers. The caspase-cleaved fragment of Par-4 (cl-Par-4) is active and plays a role in tumor suppression by inhibiting cell survival pathways. Here, we employed site-directed mutagenesis to create a cl-Par-4 point mutant (D313K). The expressed and purified D313K protein was characterized using biophysical techniques, and the results were compared to that of the wild-type (WT). We have previously demonstrated that WT cl-Par-4 attains a stable, compact, and helical conformation in the presence of a high level of salt at physiological pH. Here, we show that the D313K protein attains a similar conformation as the WT in the presence of salt, but at an approximately two times lower salt concentration. This establishes that the substitution of a basic residue for an acidic residue at position 313 alleviates inter-helical charge repulsion between dimer partners and helps to stabilize the structural conformation.
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Affiliation(s)
- Samjhana Pandey
- Biomedical Sciences Program, Old Dominion University, Norfolk, VA 23529, USA
| | - Krishna K Raut
- Department of Chemistry and Biochemistry, Old Dominion University, Norfolk, VA 23529, USA
| | - Andrea M Clark
- Department of Chemistry and Biochemistry, Old Dominion University, Norfolk, VA 23529, USA
| | - Antoine Baudin
- Greehey Children's Cancer Research Institute, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229, USA
- Department of Biochemistry and Structural Biology, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229, USA
| | - Lamya Djemri
- Department of Chemistry and Biochemistry, Old Dominion University, Norfolk, VA 23529, USA
| | - David S Libich
- Greehey Children's Cancer Research Institute, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229, USA
- Department of Biochemistry and Structural Biology, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229, USA
| | - Komala Ponniah
- Department of Chemistry and Biochemistry, Old Dominion University, Norfolk, VA 23529, USA
| | - Steven M Pascal
- Department of Chemistry and Biochemistry, Old Dominion University, Norfolk, VA 23529, USA
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3
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Araujo N, Sledziona J, Noothi SK, Burikhanov R, Hebbar N, Ganguly S, Shrestha-Bhattarai T, Zhu B, Katz WS, Zhang Y, Taylor BS, Liu J, Chen L, Weiss HL, He D, Wang C, Morris AJ, Cassis LA, Nikolova-Karakashian M, Nagareddy PR, Melander O, Evers BM, Kern PA, Rangnekar VM. Tumor Suppressor Par-4 Regulates Complement Factor C3 and Obesity. Front Oncol 2022; 12:860446. [PMID: 35425699 PMCID: PMC9004617 DOI: 10.3389/fonc.2022.860446] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2022] [Accepted: 02/28/2022] [Indexed: 11/30/2022] Open
Abstract
Prostate apoptosis response-4 (Par-4) is a tumor suppressor that induces apoptosis in cancer cells. However, the physiological function of Par-4 remains unknown. Here we show that conventional Par-4 knockout (Par-4-/-) mice and adipocyte-specific Par-4 knockout (AKO) mice, but not hepatocyte-specific Par-4 knockout mice, are obese with standard chow diet. Par-4-/- and AKO mice exhibit increased absorption and storage of fat in adipocytes. Mechanistically, Par-4 loss is associated with mdm2 downregulation and activation of p53. We identified complement factor c3 as a p53-regulated gene linked to fat storage in adipocytes. Par-4 re-expression in adipocytes or c3 deletion reversed the obese mouse phenotype. Moreover, obese human subjects showed lower expression of Par-4 relative to lean subjects, and in longitudinal studies, low baseline Par-4 levels denoted an increased risk of developing obesity later in life. These findings indicate that Par-4 suppresses p53 and its target c3 to regulate obesity.
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Affiliation(s)
- Nathalia Araujo
- Department of Toxicology and Cancer Biology, University of Kentucky, Lexington, KY, United States
| | - James Sledziona
- Department of Toxicology and Cancer Biology, University of Kentucky, Lexington, KY, United States
| | - Sunil K Noothi
- Department of Microbiology, Immunology and Molecular Genetics, University of Kentucky, Lexington, KY, United States
| | - Ravshan Burikhanov
- Department of Radiation Medicine, University of Kentucky, Lexington, KY, United States
| | - Nikhil Hebbar
- Department of Toxicology and Cancer Biology, University of Kentucky, Lexington, KY, United States
| | - Saptadwipa Ganguly
- Department of Toxicology and Cancer Biology, University of Kentucky, Lexington, KY, United States
| | - Tripti Shrestha-Bhattarai
- Department of Epidemiology and Biostatistics, Memorial Sloan Kettering Cancer Center, New York, NY, United States
| | - Beibei Zhu
- Division of Internal Medicine, University of Kentucky, Lexington, KY, United States.,Barnstable Brown Diabetes and Obesity Center, University of Kentucky, Lexington, KY, United States
| | - Wendy S Katz
- Barnstable Brown Diabetes and Obesity Center, University of Kentucky, Lexington, KY, United States.,Department of Pharmacology and Nutritional Sciences, University of Kentucky, Lexington, KY, United States
| | - Yi Zhang
- Department of Computer Science, University of Kentucky, Lexington, KY, United States
| | - Barry S Taylor
- Department of Epidemiology and Biostatistics, Memorial Sloan Kettering Cancer Center, New York, NY, United States
| | - Jinze Liu
- Department of Computer Science, University of Kentucky, Lexington, KY, United States
| | - Li Chen
- Division of Internal Medicine, University of Kentucky, Lexington, KY, United States.,Markey Cancer Center, University of Kentucky, Lexington, KY, United States
| | - Heidi L Weiss
- Division of Internal Medicine, University of Kentucky, Lexington, KY, United States.,Markey Cancer Center, University of Kentucky, Lexington, KY, United States
| | - Daheng He
- Department of Statistics, University of Kentucky, Lexington, KY, United States
| | - Chi Wang
- Markey Cancer Center, University of Kentucky, Lexington, KY, United States.,Department of Biostatistics, University of Kentucky, Lexington, KY, United States
| | - Andrew J Morris
- Division of Internal Medicine, University of Kentucky, Lexington, KY, United States.,Markey Cancer Center, University of Kentucky, Lexington, KY, United States
| | - Lisa A Cassis
- Barnstable Brown Diabetes and Obesity Center, University of Kentucky, Lexington, KY, United States.,Department of Pharmacology and Nutritional Sciences, University of Kentucky, Lexington, KY, United States
| | - Mariana Nikolova-Karakashian
- Markey Cancer Center, University of Kentucky, Lexington, KY, United States.,Department of Physiology, University of Kentucky, Lexington, KY, United States
| | | | - Olle Melander
- Department of Clinical Sciences, Lund University, Malmö, Sweden.,Department of Internal Medicine, Skåne University Hospital, Malmö, Sweden
| | - B Mark Evers
- Markey Cancer Center, University of Kentucky, Lexington, KY, United States.,Department of Surgery, University of Kentucky, Lexington, KY, United States
| | - Philip A Kern
- Division of Internal Medicine, University of Kentucky, Lexington, KY, United States.,Barnstable Brown Diabetes and Obesity Center, University of Kentucky, Lexington, KY, United States
| | - Vivek M Rangnekar
- Department of Toxicology and Cancer Biology, University of Kentucky, Lexington, KY, United States.,Department of Microbiology, Immunology and Molecular Genetics, University of Kentucky, Lexington, KY, United States.,Department of Radiation Medicine, University of Kentucky, Lexington, KY, United States.,Markey Cancer Center, University of Kentucky, Lexington, KY, United States
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4
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Truncated WT1 Protein Isoform Expression Is Increased in MCF-7 Cells with Long-Term Estrogen Depletion. Int J Breast Cancer 2021; 2021:6282514. [PMID: 34845427 PMCID: PMC8627338 DOI: 10.1155/2021/6282514] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Revised: 05/26/2021] [Accepted: 09/27/2021] [Indexed: 11/17/2022] Open
Abstract
Background The wt1 gene codes for a transcription factor that presents several protein isoforms with diverse biological properties, capable of positively and negatively regulating genes involved in proliferation, differentiation, and apoptosis. WT1 protein is overexpressed in more than 90% of breast cancer; however, its role during tumor progression is still unknown. Methodology. In this work, we analyzed the expression of WT1 isoforms in several breast cancer cells with different tumor marker statuses and an in vitro assay using MCF-7 cells cultured with long-term estrogen depletion (MCF-7 LTED cells) with the finality to mimic the process of switching from hormone-dependent to hormone-independent. Moreover, growth kinetics, sensitivity to tamoxifen, and relative expression analysis of ER and Her2/neu were performed. Results Initially, the expression of 52-54 kDa protein isoform of WT1 in the breast cancer cell line ER (+) was detected by western blot and was absent in ER (-), and the 36-38 kDa protein isoform of WT1 was detected in all cell lines analyzed. The analysis of alternative splicing by RT-PCR shows that the 17AA (+)/KTS (-) isoform of WT1 was the most frequent in the four cell lines analyzed. In vitro, the MCF-7 cells in the estrogen depletion assay show an increase in the expression of the 52-54 kDa isoform of WT1 in the first 48 hours, and this was maintained until week 13, and later, this expression was decreased, and the 36-38 kDa isoform of WT1 did not show change during the first 48 hours but from week 1 showed an increase of expression, and this remained until week 27. Growth kinetic analysis showed that MCF-7 LTED cells presented a 1.4-fold decrease in cellular proliferation compared to MCF-7 cells cultured under normal conditions. In addition, MCF-7 LTED cells showed a decrease in sensitivity to the antiproliferative effect of tamoxifen (p ≤ 0.05). Samples collected until week 57 analyzed by qRT-PCR showed an increase in the relative expression of the Her2/neu and ER. Conclusions Modulation of protein isoforms showed differential expression of WT1 isoforms dependent on estrogen receptor. The absence of 52-54 kDa and the presence of the 36-38 kDa protein isoform of WT1 were detected in ER-negative breast cancer cell lines classified as advanced stage cells. Long-term estrogen depletion assay in MCF-7 cells increased the expression of the 36-38 kDa isoform and reduced the 52-54 kDa isoform, and these cells show an increase in the expression of tumor markers of ER and Her2/neu. MCF-7 LTED cells showed low proliferation and insensitivity to tamoxifen compared to MCF-7 cells in normal conditions. These results support the theory about the relationship of the 36-38 kDa isoform of WT1 and the absence of ER function in advanced breast cancer.
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5
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Cheratta AR, Thayyullathil F, Pallichankandy S, Subburayan K, Alakkal A, Galadari S. Prostate apoptosis response-4 and tumor suppression: it's not just about apoptosis anymore. Cell Death Dis 2021; 12:47. [PMID: 33414404 PMCID: PMC7790818 DOI: 10.1038/s41419-020-03292-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2020] [Revised: 10/20/2020] [Accepted: 10/23/2020] [Indexed: 02/06/2023]
Abstract
The tumor suppressor prostate apoptosis response-4 (Par-4) has recently turned ‘twenty-five’. Beyond its indisputable role as an apoptosis inducer, an increasing and sometimes bewildering, new roles for Par-4 are being reported. These roles include its ability to regulate autophagy, senescence, and metastasis. This growing range of responses to Par-4 is reflected by our increasing understanding of the various mechanisms through which Par-4 can function. In this review, we summarize the existing knowledge on Par-4 tumor suppressive mechanisms, and discuss how the interaction of Par-4 with different regulators influence cell fate. This review also highlights the new secretory pathway that has emerged and the likely discussion on its clinical implications.
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Affiliation(s)
- Anees Rahman Cheratta
- Cell Death Signaling Laboratory, Division of Science, Experimental Research Building, New York University Abu Dhabi, PO Box 129188, Saadiyat Island Campus, Abu Dhabi, UAE
| | - Faisal Thayyullathil
- Cell Death Signaling Laboratory, Division of Science, Experimental Research Building, New York University Abu Dhabi, PO Box 129188, Saadiyat Island Campus, Abu Dhabi, UAE
| | - Siraj Pallichankandy
- Cell Death Signaling Laboratory, Division of Science, Experimental Research Building, New York University Abu Dhabi, PO Box 129188, Saadiyat Island Campus, Abu Dhabi, UAE
| | - Karthikeyan Subburayan
- Cell Death Signaling Laboratory, Division of Science, Experimental Research Building, New York University Abu Dhabi, PO Box 129188, Saadiyat Island Campus, Abu Dhabi, UAE
| | - Ameer Alakkal
- Cell Death Signaling Laboratory, Division of Science, Experimental Research Building, New York University Abu Dhabi, PO Box 129188, Saadiyat Island Campus, Abu Dhabi, UAE
| | - Sehamuddin Galadari
- Cell Death Signaling Laboratory, Division of Science, Experimental Research Building, New York University Abu Dhabi, PO Box 129188, Saadiyat Island Campus, Abu Dhabi, UAE.
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6
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Yang K, Shen J, Tan FQ, Zheng XY, Xie LP. Antitumor Activity of Small Activating RNAs Induced PAWR Gene Activation in Human Bladder Cancer Cells. Int J Med Sci 2021; 18:3039-3049. [PMID: 34220332 PMCID: PMC8241776 DOI: 10.7150/ijms.60399] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2021] [Accepted: 05/30/2021] [Indexed: 11/08/2022] Open
Abstract
Small double-stranded RNAs (dsRNAs) have been proved to effectively up-regulate the expression of particular genes by targeting their promoters. These small dsRNAs were also termed small activating RNAs (saRNAs). We previously reported that several small double-stranded RNAs (dsRNAs) targeting the PRKC apoptosis WT1 regulator (PAWR) promoter can up-regulate PAWR gene expression effectively in human cancer cells. The present study was conducted to evaluate the antitumor potential of PAWR gene induction by these saRNAs in bladder cancer. Promisingly, we found that up-regulation of PAWR by saRNA inhibited the growth of bladder cancer cells by inducing cell apoptosis and cell cycle arrest which was related to inhibition of anti‑apoptotic protein Bcl-2 and inactivation of the NF-κB and Akt pathways. The activation of the caspase cascade and the regulation of cell cycle related proteins also supported the efficacy of the treatment. Moreover, our study also showed that these saRNAs cooperated with cisplatin in the inhibition of bladder cancer cells. Overall, these data suggest that activation of PAWR by saRNA may have a therapeutic benefit for bladder cancer.
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Affiliation(s)
- Kai Yang
- Department of Urology, the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310003, P.R. China
| | - Jie Shen
- Department of Pharmacy, Traditional Chinese Medical Hospital of Zhejiang Province, Hangzhou, Zhejiang 310006, P.R. China
| | - Fu-Qing Tan
- Department of Urology, the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310003, P.R. China
| | - Xiang-Yi Zheng
- Department of Urology, the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310003, P.R. China
| | - Li-Ping Xie
- Department of Urology, the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310003, P.R. China
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7
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Santos RVC, de Sena WLB, Dos Santos FA, da Silva Filho AF, da Rocha Pitta MG, da Rocha Pitta MG, de Melo Rego MB, Pereira MC. Potential Therapeutic Agents Against Par-4 Target for Cancer Treatment: Where Are We Going? Curr Drug Targets 2020; 20:635-654. [PMID: 30474528 DOI: 10.2174/1389450120666181126122440] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Revised: 11/15/2018] [Accepted: 11/19/2018] [Indexed: 02/06/2023]
Abstract
One of the greatest challenges of cancer therapeutics nowadays is to find selective targets successfully. Prostate apoptosis response-4 (Par-4) is a selective tumor suppressor protein with an interesting therapeutic potential due to its specificity on inducing apoptosis in cancer cells. Par-4 activity and levels can be downregulated in several tumors and cancer cell types, indicating poor prognosis and treatment resistance. Efforts to increase Par-4 expression levels have been studied, including its use as a therapeutic protein by transfection with adenoviral vectors or plasmids. However, gene therapy is very complex and still presents many hurdles to be overcome. We decided to review molecules and drugs with the capacity to upregulate Par-4 and, thereby, be an alternative to reach this druggable target. In addition, Par-4 localization and function are reviewed in some cancers, clarifying how it can be used as a therapeutic target.
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Affiliation(s)
- Renata Virgínia Cavalcanti Santos
- Laboratory of Immunomodulation and New Therapeutical Approaches, Research Centre for Therapeutic Innovation Suely Galdino (NUPIT-SG), Federal University of Pernambuco, Recife, PE, Brazil
| | - Wanessa Layssa Batista de Sena
- Laboratory of Immunomodulation and New Therapeutical Approaches, Research Centre for Therapeutic Innovation Suely Galdino (NUPIT-SG), Federal University of Pernambuco, Recife, PE, Brazil
| | - Flaviana Alves Dos Santos
- Laboratory of Immunomodulation and New Therapeutical Approaches, Research Centre for Therapeutic Innovation Suely Galdino (NUPIT-SG), Federal University of Pernambuco, Recife, PE, Brazil
| | - Antônio Felix da Silva Filho
- Laboratory of Immunomodulation and New Therapeutical Approaches, Research Centre for Therapeutic Innovation Suely Galdino (NUPIT-SG), Federal University of Pernambuco, Recife, PE, Brazil
| | | | - Maira Galdino da Rocha Pitta
- Laboratory of Immunomodulation and New Therapeutical Approaches, Research Centre for Therapeutic Innovation Suely Galdino (NUPIT-SG), Federal University of Pernambuco, Recife, PE, Brazil
| | - Moacyr Barreto de Melo Rego
- Laboratory of Immunomodulation and New Therapeutical Approaches, Research Centre for Therapeutic Innovation Suely Galdino (NUPIT-SG), Federal University of Pernambuco, Recife, PE, Brazil
| | - Michelly Cristiny Pereira
- Laboratory of Immunomodulation and New Therapeutical Approaches, Research Centre for Therapeutic Innovation Suely Galdino (NUPIT-SG), Federal University of Pernambuco, Recife, PE, Brazil
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8
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Thellung S, Corsaro A, Bosio AG, Zambito M, Barbieri F, Mazzanti M, Florio T. Emerging Role of Cellular Prion Protein in the Maintenance and Expansion of Glioma Stem Cells. Cells 2019; 8:cells8111458. [PMID: 31752162 PMCID: PMC6912268 DOI: 10.3390/cells8111458] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Revised: 11/12/2019] [Accepted: 11/13/2019] [Indexed: 02/07/2023] Open
Abstract
Cellular prion protein (PrPC) is a membrane-anchored glycoprotein representing the physiological counterpart of PrP scrapie (PrPSc), which plays a pathogenetic role in prion diseases. Relatively little information is however available about physiological role of PrPC. Although PrPC ablation in mice does not induce lethal phenotypes, impairment of neuronal and bone marrow plasticity was reported in embryos and adult animals. In neurons, PrPC stimulates neurite growth, prevents oxidative stress-dependent cell death, and favors antiapoptotic signaling. However, PrPC activity is not restricted to post-mitotic neurons, but promotes cell proliferation and migration during embryogenesis and tissue regeneration in adult. PrPC acts as scaffold to stabilize the binding between different membrane receptors, growth factors, and basement proteins, contributing to tumorigenesis. Indeed, ablation of PrPC expression reduces cancer cell proliferation and migration and restores cell sensitivity to chemotherapy. Conversely, PrPC overexpression in cancer stem cells (CSCs) from different tumors, including gliomas—the most malignant brain tumors—is predictive for poor prognosis, and correlates with relapses. The mechanisms of the PrPC role in tumorigenesis and its molecular partners in this activity are the topic of the present review, with a particular focus on PrPC contribution to glioma CSCs multipotency, invasiveness, and tumorigenicity.
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Affiliation(s)
- Stefano Thellung
- Sezione di Farmacologia, Dipartimento di Medicina Interna & Centro di Eccellenza per la Ricerca Biomedica (CEBR), Università di Genova, 16132 Genova, Italy; (S.T.); (A.C.); (A.G.B.); (M.Z.); (F.B.)
| | - Alessandro Corsaro
- Sezione di Farmacologia, Dipartimento di Medicina Interna & Centro di Eccellenza per la Ricerca Biomedica (CEBR), Università di Genova, 16132 Genova, Italy; (S.T.); (A.C.); (A.G.B.); (M.Z.); (F.B.)
| | - Alessia G. Bosio
- Sezione di Farmacologia, Dipartimento di Medicina Interna & Centro di Eccellenza per la Ricerca Biomedica (CEBR), Università di Genova, 16132 Genova, Italy; (S.T.); (A.C.); (A.G.B.); (M.Z.); (F.B.)
| | - Martina Zambito
- Sezione di Farmacologia, Dipartimento di Medicina Interna & Centro di Eccellenza per la Ricerca Biomedica (CEBR), Università di Genova, 16132 Genova, Italy; (S.T.); (A.C.); (A.G.B.); (M.Z.); (F.B.)
| | - Federica Barbieri
- Sezione di Farmacologia, Dipartimento di Medicina Interna & Centro di Eccellenza per la Ricerca Biomedica (CEBR), Università di Genova, 16132 Genova, Italy; (S.T.); (A.C.); (A.G.B.); (M.Z.); (F.B.)
| | - Michele Mazzanti
- Dipartimento di Bioscienze, Università di Milano, 20133 Milano, Italy
- Correspondence: (T.F.); (M.M.); Tel.: +39-01-0353-8806 (T.F.); +39-02-5031-4958 (M.M.)
| | - Tullio Florio
- Sezione di Farmacologia, Dipartimento di Medicina Interna & Centro di Eccellenza per la Ricerca Biomedica (CEBR), Università di Genova, 16132 Genova, Italy; (S.T.); (A.C.); (A.G.B.); (M.Z.); (F.B.)
- IRCCS Ospedale Policlinico San Martino, 16132 Genova, Italy
- Correspondence: (T.F.); (M.M.); Tel.: +39-01-0353-8806 (T.F.); +39-02-5031-4958 (M.M.)
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9
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Clark AM, Ponniah K, Warden MS, Raitt EM, Smith BG, Pascal SM. Tetramer formation by the caspase-activated fragment of the Par-4 tumor suppressor. FEBS J 2019; 286:4060-4073. [PMID: 31177609 DOI: 10.1111/febs.14955] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Revised: 05/10/2019] [Accepted: 06/06/2019] [Indexed: 11/27/2022]
Abstract
The prostate apoptosis response-4 (Par-4) tumor suppressor can selectively kill cancer cells via apoptosis while leaving healthy cells unharmed. Full length Par-4 has been shown to be predominantly intrinsically disordered in vitro under neutral conditions. As part of the apoptotic process, cellular Par-4 is cleaved at D131 by caspase-3, which generates a 24 kDa C-terminal activated fragment (cl-Par-4) that enters the nucleus and inhibits pro-survival genes, thereby preventing cancer cell proliferation. Here, the structure of cl-Par-4 was investigated using CD spectroscopy, dynamic light scattering, intrinsic tyrosine fluorescence, and size exclusion chromatography with mutli-angle light scattering. Biophysical characterization shows that cl-Par-4 aggregates and is disordered at low ionic strength. However, with increasing ionic strength, cl-Par-4 becomes progressively more helical and less aggregated, ultimately forming largely ordered tetramers at high NaCl concentration. These results, together with previous results showing induced folding at acidic pH, suggest that the in vivo structure and self-association state of cl-Par-4 may be strongly dependent upon cellular environment.
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Affiliation(s)
- Andrea M Clark
- Department of Chemistry and Biochemistry, Old Dominion University, Norfolk, VA, USA
| | - Komala Ponniah
- Department of Chemistry and Biochemistry, Old Dominion University, Norfolk, VA, USA
| | - Meghan S Warden
- Department of Chemistry and Biochemistry, Old Dominion University, Norfolk, VA, USA
| | - Emily M Raitt
- Department of Chemistry and Biochemistry, Old Dominion University, Norfolk, VA, USA
| | - Benjamin G Smith
- Department of Chemistry and Biochemistry, Old Dominion University, Norfolk, VA, USA
| | - Steven M Pascal
- Department of Chemistry and Biochemistry, Old Dominion University, Norfolk, VA, USA
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10
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Greene JT, Mani R, Ramaswamy R, Frissora F, Yano M, Zapolnik K, Harrington B, Wasmuth R, Tran M, Mo X, McKenna M, Rangnekar VM, Byrd JC, Bondada S, Muthusamy N. Par-4 overexpression impedes leukemogenesis in the Eµ-TCL1 leukemia model through downregulation of NF-κB signaling. Blood Adv 2019; 3:1255-1266. [PMID: 30987970 PMCID: PMC6482354 DOI: 10.1182/bloodadvances.2018025973] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Accepted: 02/23/2019] [Indexed: 01/25/2023] Open
Abstract
Prostate apoptosis response 4 (Par-4) is a tumor suppressor that prevents proliferation and induces cell death in several solid tumors. However, its role in B-cell malignancies has not been elucidated. To describe the role of Par-4 in chronic lymphocytic leukemia (CLL) pathogenesis, we developed a B-cell-specific human Par-4-overexpressing mouse model of CLL using the TCL1 leukemia model. While Par-4 transgenic mice did not display any obvious defects in B-cell development or function, disease burden as evidenced by abundance of CD19+CD5+ B cells in the peripheral blood was significantly reduced in Par-4 × TCL1 mice compared with TCL1 littermates. This conferred a survival advantage on the Par-4-overexpressing mice. In addition, a B-cell-specific knockout model displayed the opposite effect, where lack of Par-4 expression resulted in accelerated disease progression and abbreviated survival in the TCL1 model. Histological and flow cytometry-based analysis of spleen and bone marrow upon euthanasia revealed comparable levels of malignant B-cell infiltration in Par-4 × TCL1 and TCL1 individuals, indicating delayed but pathologically normal disease progression in Par-4 × TCL1 mice. In vivo analysis of splenic B-cell proliferation by 5-ethynyl-2-deoxyuridine incorporation indicated >50% decreased expansion of CD19+CD5+ cells in Par-4 × TCL1 mice compared with TCL1 littermates. Moreover, reduced nuclear p65 levels were observed in Par-4 × TCL1 splenic B cells compared with TCL1, suggesting suppressed NF-κB signaling. These findings have identified an in vivo antileukemic role for Par-4 through an NF-κB-dependent mechanism in TCL1-mediated CLL-like disease progression.
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MESH Headings
- Animals
- Apoptosis Regulatory Proteins/biosynthesis
- Carcinogenesis/genetics
- Carcinogenesis/metabolism
- Humans
- Leukemia, Lymphocytic, Chronic, B-Cell/genetics
- Leukemia, Lymphocytic, Chronic, B-Cell/metabolism
- Leukemia, Lymphocytic, Chronic, B-Cell/pathology
- Mice
- Mice, Transgenic
- Neoplasms, Experimental/genetics
- Neoplasms, Experimental/metabolism
- Neoplasms, Experimental/pathology
- Proto-Oncogene Proteins/genetics
- Proto-Oncogene Proteins/metabolism
- Signal Transduction
- Tumor Suppressor Proteins/genetics
- Tumor Suppressor Proteins/metabolism
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Affiliation(s)
- J T Greene
- The James Comprehensive Cancer Center and
| | | | | | | | - Max Yano
- The James Comprehensive Cancer Center and
| | | | | | | | - Minh Tran
- The James Comprehensive Cancer Center and
| | - Xiaokui Mo
- Center for Biostatistics, The Ohio State University, Columbus, OH; and
| | - Mary McKenna
- Markey Cancer Center, University of Kentucky, Lexington, KY
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11
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Dai W, Mu L, Cui Y, Li Y, Chen P, Xie H, Wang X. Berberine Promotes Apoptosis of Colorectal Cancer via Regulation of the Long Non-Coding RNA (lncRNA) Cancer Susceptibility Candidate 2 (CASC2)/AU-Binding Factor 1 (AUF1)/B-Cell CLL/Lymphoma 2 (Bcl-2) Axis. Med Sci Monit 2019; 25:730-738. [PMID: 30681073 PMCID: PMC6357823 DOI: 10.12659/msm.912082] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Background Berberine, a natural isoquinoline alkaloid derived from Berberis genus plants, has been reported to have anti-cancer effects. While cell behavior can be modulated by long non-coding RNAs (lncRNAs), the contributions of lncRNAs in progression and berberine effects on colorectal cancer are largely unknown. Therefore, the present study investigated the involvement and regulatory function of lncRNA cancer susceptibility candidate 2 (CASC2) during the treatment of human colorectal cancer using berberine. Material/Methods Reverse transcription-quantitative PCR (RT-qPCR) was performed to detect the expression levels of lncRNA CASC2 and Bcl-2 mRNA in colorectal cancer cells. MTT assay was performed to evaluate cell viability. Flow cytometry and TUNEL assay were used to analyze the apoptosis of cancer cells. RNA immunoprecipitation (RIP) assay was done to verify the interaction between lncRNA CASC2 and (AU-binding factor 1) AUF1, or AUF1 and B-cell CLL/lymphoma 2 (Bcl-2). Results Treatment with berberine suppressed cell viability of colorectal cancer by promoting apoptosis level. LncRNA CASC2 was upregulated in cells treated with berberine, and knockdown of lncRNA CASC2 reversed the berberine-induced apoptosis. In addition, anti-apoptotic gene Bcl-2 was suppressed by berberine treatment and lncRNA CASC2, inducing the pro-apoptotic effects. Moreover, lncRNA CASC2 binds to AUF1, which sequestered AUF1 from binding to Bcl-2 mRNA, thus inducing the inactivation of Bcl-2 translation. Conclusions Our study reveals that lncRNA CASC2 mediates the berberine-induced pro-apoptotic effect via inhibition of Bcl-2 expression at the post-transcriptional level.
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Affiliation(s)
- Wei Dai
- Medical Laboratory, West China Second University Hospital, Sichuan University, Chengdu, Sichuan, China (mainland).,Key Laboratory of Obstetric and Gynecologic and Pediatric Diseases and Birth Defects, Ministry of Education, Chengdu, Sichuan, China (mainland)
| | - Liyuan Mu
- Medical Laboratory, West China Second University Hospital, Sichuan University, Chengdu, Sichuan, China (mainland).,Key Laboratory of Obstetric and Gynecologic and Pediatric Diseases and Birth Defects, Ministry of Education, Chengdu, Sichuan, China (mainland)
| | - Yali Cui
- Medical Laboratory, West China Second University Hospital, Sichuan University, Chengdu, Sichuan, China (mainland).,Key Laboratory of Obstetric and Gynecologic and Pediatric Diseases and Birth Defects, Ministry of Education, Chengdu, Sichuan, China (mainland)
| | - Yingying Li
- Medical Laboratory, West China Second University Hospital, Sichuan University, Chengdu, Sichuan, China (mainland).,Key Laboratory of Obstetric and Gynecologic and Pediatric Diseases and Birth Defects, Ministry of Education, Chengdu, Sichuan, China (mainland)
| | - Ping Chen
- Medical Laboratory, West China Second University Hospital, Sichuan University, Chengdu, Sichuan, China (mainland).,Key Laboratory of Obstetric and Gynecologic and Pediatric Diseases and Birth Defects, Ministry of Education, Chengdu, Sichuan, China (mainland)
| | - Hongjian Xie
- Medical Laboratory, West China Second University Hospital, Sichuan University, Chengdu, Sichuan, China (mainland).,Key Laboratory of Obstetric and Gynecologic and Pediatric Diseases and Birth Defects, Ministry of Education, Chengdu, Sichuan, China (mainland)
| | - Xia Wang
- Medical Laboratory, West China Second University Hospital, Sichuan University, Chengdu, Sichuan, China (mainland).,Key Laboratory of Obstetric and Gynecologic and Pediatric Diseases and Birth Defects, Ministry of Education, Chengdu, Sichuan, China (mainland)
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12
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Clark AM, Ponniah K, Warden MS, Raitt EM, Yawn AC, Pascal SM. pH-Induced Folding of the Caspase-Cleaved Par-4 Tumor Suppressor: Evidence of Structure Outside of the Coiled Coil Domain. Biomolecules 2018; 8:biom8040162. [PMID: 30518159 PMCID: PMC6316887 DOI: 10.3390/biom8040162] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2018] [Revised: 11/20/2018] [Accepted: 11/22/2018] [Indexed: 12/13/2022] Open
Abstract
Prostate apoptosis response-4 (Par-4) is a 38 kDa largely intrinsically disordered tumor suppressor protein that functions in cancer cell apoptosis. Par-4 down-regulation is often observed in cancer while up-regulation is characteristic of neurodegenerative conditions such as Alzheimer’s disease. Cleavage of Par-4 by caspase-3 activates tumor suppression via formation of an approximately 25 kDa fragment (cl-Par-4) that enters the nucleus and inhibits Bcl-2 and NF-ƙB, which function in pro-survival pathways. Here, we have investigated the structure of cl-Par-4 using biophysical techniques including circular dichroism (CD) spectroscopy, dynamic light scattering (DLS), and intrinsic tyrosine fluorescence. The results demonstrate pH-dependent folding of cl-Par-4, with high disorder and aggregation at neutral pH, but a largely folded, non-aggregated conformation at acidic pH.
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Affiliation(s)
- Andrea M Clark
- Department of Chemistry and Biochemistry, Old Dominion University, Norfolk, VA 23529, USA.
| | - Komala Ponniah
- Department of Chemistry and Biochemistry, Old Dominion University, Norfolk, VA 23529, USA.
| | - Meghan S Warden
- Department of Chemistry and Biochemistry, Old Dominion University, Norfolk, VA 23529, USA.
| | - Emily M Raitt
- Department of Chemistry and Biochemistry, Old Dominion University, Norfolk, VA 23529, USA.
| | - Andrea C Yawn
- Department of Chemistry and Biochemistry, Old Dominion University, Norfolk, VA 23529, USA.
| | - Steven M Pascal
- Department of Chemistry and Biochemistry, Old Dominion University, Norfolk, VA 23529, USA.
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13
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Shelke GV, Jagtap JC, Kim DK, Shah RD, Das G, Shivayogi M, Pujari R, Shastry P. TNF-α and IFN-γ Together Up-Regulates Par-4 Expression and Induce Apoptosis in Human Neuroblastomas. Biomedicines 2017; 6:biomedicines6010004. [PMID: 29278364 PMCID: PMC5874661 DOI: 10.3390/biomedicines6010004] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2017] [Revised: 12/15/2017] [Accepted: 12/19/2017] [Indexed: 01/18/2023] Open
Abstract
The objective of this study was to examine the combined effect of Interferon-gamma (IFN-γ) and Tumor Necrosis factor-alpha (TNF-α) on cytotoxicity and expression of prostate apoptosis response-4 (Par-4) and Par-4 interacting proteins B-cell lymphoma (Bcl-2), nuclear factor kappa-light-chain-enhancer of activated B cells/p65 subunit (NF-κB/p65), Ak mouse strain thymoma (Akt) in human neuroblastoma (NB) cells. Materials and methods included human neuroblastoma cell lines-SK-N-MC, SK-N-SH, and SH-SY5Y, which were treated with IFN-γ and TNF-α individually, or in combination, and were assessed for viability by tetrazolium (MTT) assay. Apoptosis was monitored by hypodiploid population (by flow cytometry), DNA fragmentation, Poly (ADP-ribose) polymerase (PARP) cleavage, and caspase-8 activity. Transcript level of Par-4 was measured by RT-PCR. Protein levels of Par-4 and suppressor of cytokine signaling 3 (SOCS-3) were assessed by immunoblotting. Cellular localization of Par-4 and p65 was examined by immunofluorescence. Unbiased transcript analysis for IFN-γ, TNF-α, and Par-4 were analyzed from three independent clinical datasets from neuroblastoma patients. In terms of results, SK-N-MC cells treated with a combination of, but not individually with, IFN-γ and TNF-α induced apoptosis characterized by hypodiploidy, DNA fragmentation, PARP cleavage, and increased caspase-8 activity. Apoptosis was associated with up-regulation of Par-4 mRNA and protein expression. Immunofluorescence studies revealed that Par-4 was localized exclusively in cytoplasm in SK-N-MC cells cultured for 24 h. but showed nuclear localization at 48 h. Treatment with IFN-γ and TNF-α together enhanced the intensity of nuclear Par-4. In gene expression, data from human neuroblastoma patients, levels of IFN-γ, and TNF-α have strong synergy with Par-4 expression and provide good survival advantage. The findings also demonstrated that apoptosis was associated with reduced level of pro-survival proteins–Bcl-2 and Akt and NF-κB/p65. Furthermore, the apoptotic effect induced by IFN-γ-induced Signal Transducer and Activator of Transcription-1(STAT-1), and could be due to down-regulation of suppressor of cytokine signaling-3 (SOCS3). The study concludes that a combinatorial approach using IFN-γ and TNF-α can be explored to maximize the effect in chemotherapy in neuroblastoma, and implies a role for Par-4 in the process.
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Affiliation(s)
- Ganesh V Shelke
- National Centre for Cell Science, Savitribai Phule Pune University, Ganeshkhind, Pune 411007, India
- Current address: Krefting Research Centre, University of Gothenburg, Box-424, SE-405 30 Gothenburg, Sweden.
| | - Jayashree C Jagtap
- National Centre for Cell Science, Savitribai Phule Pune University, Ganeshkhind, Pune 411007, India.
| | - Dae-Kyum Kim
- Donnelly Centre, University of Toronto, Toronto, ON M5S 3E1, Canada.
- Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, Toronto, ON M5G 1X5, Canada.
| | - Reecha D Shah
- National Centre for Cell Science, Savitribai Phule Pune University, Ganeshkhind, Pune 411007, India.
| | - Gowry Das
- National Centre for Cell Science, Savitribai Phule Pune University, Ganeshkhind, Pune 411007, India.
| | | | - Radha Pujari
- Rasayani Biologics Pvt Ltd, 48/7, Mhalunge-Nande Road, Mhalunge, Pune 411045, India.
| | - Padma Shastry
- National Centre for Cell Science, Savitribai Phule Pune University, Ganeshkhind, Pune 411007, India.
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14
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Abstract
The prostate apoptosis response protein 4 (Par-4) is a tumor-suppressor that has been shown to induce cancer-cell selective apoptosis in a variety of cancers. The regulation of Par-4 expression and activity is a relatively understudied area, and identifying novel regulators of Par-4 may serve as novel therapeutic targets. To identify novel regulators of Par-4, a co-immunoprecipitation was performed in colon cancer cells, and co-precipitated proteins were identified by mass-spectometry. TRIM21 was identified as a novel interacting partner of Par-4, and further shown to interact with Par-4 endogenously and through its PRY-SPRY domain. Additional studies show that TRIM21 downregulates Par-4 levels in response to cisplatin, and that TRIM21 can increase the resistance of colon cancer cells to cisplatin. Furthermore, forced Par-4 expression can sensitize pancreatic cancer cells to cisplatin. Finally, we demonstrate that TRIM21 expression predicts survival in pancreatic cancer patients. Our work highlights a novel mechanism of Par-4 regulation, and identifies a novel prognostic marker and potential therapeutic target for pancreatic cancer.
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Affiliation(s)
- Jeffrey Q Nguyen
- a Department of Medicine and Penn State Hershey Cancer Institute , Penn State College of Medicine , Hershey , PA , USA
| | - Rosalyn B Irby
- a Department of Medicine and Penn State Hershey Cancer Institute , Penn State College of Medicine , Hershey , PA , USA
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15
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Meynier S, Kramer M, Ribaux P, Tille JC, Delie F, Petignat P, Cohen M. Role of PAR-4 in ovarian cancer. Oncotarget 2016; 6:22641-52. [PMID: 26246468 PMCID: PMC4673188 DOI: 10.18632/oncotarget.4010] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2015] [Accepted: 05/14/2015] [Indexed: 12/22/2022] Open
Abstract
Prostate apoptosis response-4 (PAR-4) is considered as a tumour suppressor due to its ability to selectively induce cell apoptosis in most cancer cells. However little is known about the role of PAR-4 in ovarian cancer. In this study, we investigated for the first time the role of PAR-4 in ovarian carcinogenesis. We showed that PAR-4 mRNA level is not significantly different between healthy and cancer ovarian cells. Immunohistochemistry on ovarian tissue showed that ovarian cancer cells are positive for PAR-4 nuclear and cytoplasmic staining whereas ovarian healthy cells are negative for PAR-4 nuclear staining. We then studied the role of PAR-4 in cell apoptosis. We determined that PAR-4 induces cell apoptosis in response to stimuli, in vitro, but is also involved in the relocation of GRP78 from endoplasmic reticulum to the cell surface of ovarian cancer cell line (SKOV-3 cells). In ovo, PAR-4 decreases ovarian tumour development and increases the response to taxol treatment. These observations suggest that PAR-4 is a very interesting therapeutic target against ovarian carcinogenesis.
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Affiliation(s)
- Sonia Meynier
- Department of Gynecology Obstetrics, Faculty of Medicine, University of Geneva, Switzerland
| | - Marianne Kramer
- Department of Gynecology Obstetrics, Faculty of Medicine, University of Geneva, Switzerland
| | - Pascale Ribaux
- Department of Gynecology Obstetrics, Faculty of Medicine, University of Geneva, Switzerland
| | - Jean-Christophe Tille
- Division of Clinical Pathology, Geneva University Hospital, University of Geneva, Switzerland
| | - Florence Delie
- School of Pharmaceutical Sciences, University of Geneva, University of Lausanne, Switzerland
| | - Patrick Petignat
- Department of Gynecology Obstetrics, Faculty of Medicine, University of Geneva, Switzerland
| | - Marie Cohen
- Department of Gynecology Obstetrics, Faculty of Medicine, University of Geneva, Switzerland
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16
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Brasseur K, Fabi F, Adam P, Parent S, Lessard L, Asselin E. Post-translational regulation of the cleaved fragment of Par-4 in ovarian and endometrial cancer cells. Oncotarget 2016; 7:36971-36987. [PMID: 27175591 PMCID: PMC5095052 DOI: 10.18632/oncotarget.9235] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Accepted: 04/24/2016] [Indexed: 11/25/2022] Open
Abstract
We recently reported the caspase3-dependent cleavage of Par-4 resulting in the accumulation of a 25kDa cleaved-Par-4 (cl-Par-4) fragment and we investigated in the present study the mechanisms regulating this fragment using cl-Par-4-expressing stable clones derived from ovarian and endometrial cancer cell lines.Cl-Par-4 protein was weakly express in all stable clones despite constitutive expression. However, upon cisplatin treatment, cl-Par-4 levels increased up to 50-fold relative to baseline conditions. Treatment of stable clones with proteasome and translation inhibitors revealed that cisplatin exposure might in fact protect cl-Par-4 from proteasome-dependent degradation. PI3K and MAPK pathways were also implicated as evidenced by an increase of cl-Par-4 in the presence of PI3K inhibitors and a decrease using MAPK inhibitors. Finally using bioinformatics resources, we found diverse datasets showing similar results to those we observed with the proteasome and cl-Par-4 further supporting our data.These new findings add to the complex mechanisms regulating Par-4 expression and activity, and justify further studies addressing the biological significance of this phenomenon in gynaecological cancer cells.
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Affiliation(s)
- Kevin Brasseur
- Research Group in Cellular Signaling, Department of Medical Biology, Université du Québec à Trois-Rivières, Trois-Rivières, Québec G9A 5H7, Canada
| | - François Fabi
- Research Group in Cellular Signaling, Department of Medical Biology, Université du Québec à Trois-Rivières, Trois-Rivières, Québec G9A 5H7, Canada
| | - Pascal Adam
- Research Group in Cellular Signaling, Department of Medical Biology, Université du Québec à Trois-Rivières, Trois-Rivières, Québec G9A 5H7, Canada
| | - Sophie Parent
- Research Group in Cellular Signaling, Department of Medical Biology, Université du Québec à Trois-Rivières, Trois-Rivières, Québec G9A 5H7, Canada
| | - Laurent Lessard
- Research Group in Cellular Signaling, Department of Medical Biology, Université du Québec à Trois-Rivières, Trois-Rivières, Québec G9A 5H7, Canada
| | - Eric Asselin
- Research Group in Cellular Signaling, Department of Medical Biology, Université du Québec à Trois-Rivières, Trois-Rivières, Québec G9A 5H7, Canada
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17
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Rah B, ur Rasool R, Nayak D, Yousuf SK, Mukherjee D, Kumar LD, Goswami A. PAWR-mediated suppression of BCL2 promotes switching of 3-azido withaferin A (3-AWA)-induced autophagy to apoptosis in prostate cancer cells. Autophagy 2016; 11:314-31. [PMID: 25803782 DOI: 10.1080/15548627.2015.1017182] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
An active medicinal component of plant origin with an ability to overcome autophagy by inducing apoptosis should be considered a therapeutically active lead pharmacophore to control malignancies. In this report, we studied the effect of concentration-dependent 3-AWA (3-azido withaferin A) sensitization to androgen-independent prostate cancer (CaP) cells which resulted in a distinct switching of 2 interrelated conserved biological processes, i.e. autophagy and apoptosis. We have observed 3 distinct parameters which are hallmarks of autophagy in our studies. First, a subtoxic concentration of 3-AWA resulted in an autophagic phenotype with an elevation of autophagy markers in prostate cancer cells. This led to a massive accumulation of MAP1LC3B and EGFP-LC3B puncta coupled with gradual degradation of SQSTM1. Second, higher toxic concentrations of 3-AWA stimulated ER stress in CaP cells to turn on apoptosis within 12 h by elevating the expression of the proapoptotic protein PAWR, which in turn suppressed the autophagy-related proteins BCL2 and BECN1. This inhibition of BECN1 in CaP cells, leading to the disruption of the BCL2-BECN1 interaction by overexpressed PAWR has not been reported so far. Third, we provide evidence that pawr-KO MEFs exhibited abundant autophagy signs even at toxic concentrations of 3-AWA underscoring the relevance of PAWR in switching of autophagy to apoptosis. Last but not least, overexpression of EGFP-LC3B and DS-Red-BECN1 revealed a delayed apoptosis turnover at a higher concentration of 3-AWA in CaP cells. In summary, this study provides evidence that 3-AWA is a strong anticancer candidate to abrogate protective autophagy. It also enhanced chemosensitivity by sensitizing prostate cancer cells to apoptosis through induction of PAWR endorsing its therapeutic potential.
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Key Words
- 3-AWA, 3-azido withaferin A
- 3-azido withaferin A
- AO, acridine orange
- ATG, autophagy-related
- AVOs, acidic vesicular organelles
- BAD, BCL2-associated agonist of cell death
- BAF A1, bafilomycin A1
- BCL2
- BCL2, B-cell CLL/lymphoma 2
- BECN1
- BECN1, Beclin 1, autophagy-related
- CASP3, caspase 3
- CASP9, caspase 9
- CQ, chloroquine
- CYCS, cytochrome c, somatic
- CaP, prostate cancer cells
- DAPI, 4’6-diamidino-2-phenylindole
- DCF, dichlorofluorescein
- DDIT3/CHOP, DNA-damage-inducible transcript 3
- EIF2AK3/PERK, eukaryotic initiation translation factor 2-α kinase 3
- ER, endoplasmic reticulum
- HSPA5/GRP78, heat shock 70kDa protein 5 (glucose-regulated protein, 78kDa)
- MAP1LC3B/LC3B, microtubule-associated protein 1 light chain 3 β
- MDC, monodansylcadaverine
- MEFs, mouse embryonic fibroblasts
- MMPψ, mitochondrial membrane potential
- MTOR, mechanistic target of rapamycin
- NAC, N-acetyl-L-cysteine
- PARP1, poly (ADP-ribose) polymerase 1
- PAWR
- PAWR/Par-4, PRKC, apoptosis, WT1, regulator
- PRKCZ/PKCζ, protein kinase C, zeta
- SQSTM1/p62, sequestosome 1
- WT1, Wilms tumor 1
- apoptosis
- autophagy
- myrAKT1, myristoylated v-akt murine thymoma viral oncogene homolog 1
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Affiliation(s)
- Bilal Rah
- a Academy of Scientific & Innovative Research (AcSIR) ; New Delhi , India
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18
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Yang K, Shen J, Chen SW, Qin J, Zheng XY, Xie LP. Upregulation of PAWR by small activating RNAs induces cell apoptosis in human prostate cancer cells. Oncol Rep 2016; 35:2487-93. [PMID: 26797252 DOI: 10.3892/or.2016.4582] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2015] [Accepted: 01/07/2016] [Indexed: 11/06/2022] Open
Abstract
RNA activation (RNAa) is a promising discovery whereby expression of a particular gene can be induced by targeting its promoter using small double-stranded RNAs (dsRNAs) also termed small activating RNAs (saRNAs). We previously reported that several small dsRNAs targeting the PRKC apoptosis WT1 regulator (PAWR) promoter can upregulate PAWR gene expression effectively in human cancer cells. The present study was conducted to evaluate the antitumor potential of PAWR gene induction by these saRNAs in prostate cancer cells. Promisingly, we found that upregulation of PAWR by saRNA inhibited the growth of prostate cancer cells by inducing cell apoptosis which was related to inactivation of the NF-κB and Akt pathways. The decreased anti‑apoptotic protein Bcl-2 and activation of the caspase cascade and poly(ADP-ribose) polymerase (PARP) also supported the efficacy of the treatment. Overall, these data suggest that activation of PAWR by saRNA may have a therapeutic benefit for prostate and other types of cancer.
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Affiliation(s)
- Kai Yang
- Department of Urology, The First Affiliated Hospital, Zhejiang University, Hangzhou, Zhejiang 310003, P.R. China
| | - Jie Shen
- Department of Pharmacy, Traditional Chinese Medical Hospital of Zhejiang Province, Hangzhou, Zhejiang 310006, P.R. China
| | - Shan-Wen Chen
- Department of Urology, The First Affiliated Hospital, Zhejiang University, Hangzhou, Zhejiang 310003, P.R. China
| | - Jie Qin
- Department of Urology, The First Affiliated Hospital, Zhejiang University, Hangzhou, Zhejiang 310003, P.R. China
| | - Xiang-Yi Zheng
- Department of Urology, The First Affiliated Hospital, Zhejiang University, Hangzhou, Zhejiang 310003, P.R. China
| | - Li-Ping Xie
- Department of Urology, The First Affiliated Hospital, Zhejiang University, Hangzhou, Zhejiang 310003, P.R. China
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19
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The ZNF304-integrin axis protects against anoikis in cancer. Nat Commun 2015; 6:7351. [PMID: 26081979 DOI: 10.1038/ncomms8351] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2015] [Accepted: 04/29/2015] [Indexed: 01/15/2023] Open
Abstract
Ovarian cancer (OC) is a highly metastatic disease, but no effective strategies to target this process are currently available. Here, an integrative computational analysis of the Cancer Genome Atlas OC data set and experimental validation identifies a zinc finger transcription factor ZNF304 associated with OC metastasis. High tumoral ZNF304 expression is associated with poor overall survival in OC patients. Through reverse phase protein array analysis, we demonstrate that ZNF304 promotes multiple proto-oncogenic pathways important for cell survival, migration and invasion. ZNF304 transcriptionally regulates β1 integrin, which subsequently regulates Src/focal adhesion kinase and paxillin and prevents anoikis. In vivo delivery of ZNF304 siRNA by a dual assembly nanoparticle leads to sustained gene silencing for 14 days, increased anoikis and reduced tumour growth in orthotopic mouse models of OC. Taken together, ZNF304 is a transcriptional regulator of β1 integrin, promotes cancer cell survival and protects against anoikis in OC.
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20
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Hebbar N, Shrestha-Bhattarai T, Rangnekar VM. Cancer-selective apoptosis by tumor suppressor par-4. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2014; 818:155-66. [PMID: 25001535 DOI: 10.1007/978-1-4471-6458-6_7] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
Tumor suppressor genes play an important role in preventing neoplastic transformation and maintaining normal tissue homeostasis. Par-4 is one such tumor suppressor which is unique in its ability to selectively induce apoptosis in cancer cells while leaving the normal cells unaffected. The cancer cell specific activity of Par-4 is elicited through intracellular as well as extracellular mechanisms. Intracellularly Par-4 acts through the inhibition of pro-survival pathways and activation of Fas mediated apoptosis whereas extracellular (secreted Par-4) acts by binding to cell surface GRP78 leading to activation of the extrinsic apoptotic pathway. Many studies have highlighted the importance of Par-4 not only in preventing cancer development/recurrence but also as a promising anticancer therapeutic agent.
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Affiliation(s)
- Nikhil Hebbar
- Graduate Center for Toxicology, University of Kentucky, Combs Building Room 326, Lexington, KY, USA
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21
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Abstract
The WT1 (Wilms' tumour 1) gene encodes a zinc finger transcription factor and RNA-binding protein that direct the development of several organs and tissues. WT1 manifests both tumour suppressor and oncogenic activities, but the reasons behind these opposing functions are still not clear. As a transcriptional regulator, WT1 can either activate or repress numerous target genes resulting in disparate biological effects such as growth, differentiation and apoptosis. The complex nature of WT1 is exemplified by a plethora of isoforms, post-translational modifications and multiple binding partners. How WT1 achieves specificity to regulate a large number of target genes involved in diverse physiological processes is the focus of the present review. We discuss the wealth of the growing molecular information that defines our current understanding of the versatility and utility of WT1 as a master regulator of organ development, a tumour suppressor and an oncogene.
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Kang HJ, Kendrick S, Hecht SM, Hurley LH. The transcriptional complex between the BCL2 i-motif and hnRNP LL is a molecular switch for control of gene expression that can be modulated by small molecules. J Am Chem Soc 2014; 136:4172-85. [PMID: 24559432 PMCID: PMC3985447 DOI: 10.1021/ja4109352] [Citation(s) in RCA: 184] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
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In a companion paper (DOI: 10.021/ja410934b) we demonstrate that the C-rich
strand of the cis-regulatory element in the BCL2 promoter element
is highly dynamic in nature and can form either an i-motif or a flexible
hairpin. Under physiological conditions these two secondary DNA structures
are found in an equilibrium mixture, which can be shifted by the addition
of small molecules that trap out either the i-motif (IMC-48) or the
flexible hairpin (IMC-76). In cellular experiments we demonstrate
that the addition of these molecules has opposite effects on BCL2 gene expression and furthermore that these effects
are antagonistic. In this contribution we have identified a transcriptional
factor that recognizes and binds to the BCL2 i-motif
to activate transcription. The molecular basis for the recognition
of the i-motif by hnRNP LL is determined, and we demonstrate that
the protein unfolds the i-motif structure to form a stable single-stranded
complex. In subsequent experiments we show that IMC-48 and IMC-76
have opposite, antagonistic effects on the formation of the hnRNP
LL–i-motif complex as well as on the transcription factor occupancy
at the BCL2 promoter. For the first time we propose
that the i-motif acts as a molecular switch that controls gene expression
and that small molecules that target the dynamic equilibrium of the
i-motif and the flexible hairpin can differentially modulate gene
expression.
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Affiliation(s)
- Hyun-Jin Kang
- College of Pharmacy and §BIO5 Institute, University of Arizona , Tucson, Arizona 85721, United States
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Jagtap JC, Dawood P, Shah RD, Chandrika G, Natesh K, Shiras A, Hegde AS, Ranade D, Shastry P. Expression and regulation of prostate apoptosis response-4 (Par-4) in human glioma stem cells in drug-induced apoptosis. PLoS One 2014; 9:e88505. [PMID: 24523904 PMCID: PMC3921173 DOI: 10.1371/journal.pone.0088505] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2013] [Accepted: 01/13/2014] [Indexed: 12/25/2022] Open
Abstract
Gliomas are the most common and aggressive of brain tumors in adults. Cancer stem cells (CSC) contribute to chemoresistance in many solid tumors including gliomas. The function of prostate apoptosis response-4 (Par-4) as a pro-apoptotic protein is well documented in many cancers; however, its role in CSC remains obscure. In this study, we aimed to explore the role of Par-4 in drug-induced cytotoxicity using human glioma stem cell line--HNGC-2 and primary culture (G1) derived from high grade glioma. We show that among the panel of drugs- lomustine, carmustine, UCN-01, oxaliplatin, temozolomide and tamoxifen (TAM) screened, only TAM induced cell death and up-regulated Par-4 levels significantly. TAM-induced apoptosis was confirmed by PARP cleavage, Annexin V and propidium iodide staining and caspase-3 activity. Knock down of Par-4 by siRNA inhibited cell death by TAM, suggesting the role of Par-4 in induction of apoptosis. We also demonstrate that the mechanism involves break down of mitochondrial membrane potential, down regulation of Bcl-2 and reduced activation of Akt and ERK 42/44. Secretory Par-4 and GRP-78 were significantly expressed in HNGC-2 cells on exposure to TAM and specific antibodies to these molecules inhibited cell death suggesting that extrinsic Par-4 is important in TAM-induced apoptosis. Interestingly, TAM decreased the expression of neural stem cell markers--Nestin, Bmi1, Vimentin, Sox2, and Musashi in HNGC-2 cell line and G1 cells implicating its potential as a stemness inhibiting drug. Based on these data and our findings that enhanced levels of Par-4 sensitize the resistant glioma stem cells to drug-induced apoptosis, we propose that Par-4 may be explored for evaluating anti-tumor agents in CSC.
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Affiliation(s)
| | | | | | | | - Kumar Natesh
- National Centre for Cell Science (NCCS), Pune, India
| | - Anjali Shiras
- National Centre for Cell Science (NCCS), Pune, India
| | - Amba S. Hegde
- National Centre for Cell Science (NCCS), Pune, India
| | - Deepak Ranade
- Department of Neurosurgery, D. Y. Patil Medical College, Pune, India
| | - Padma Shastry
- National Centre for Cell Science (NCCS), Pune, India
- * E-mail:
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Par-4/THAP1 complex and Notch3 competitively regulated pre-mRNA splicing of CCAR1 and affected inversely the survival of T-cell acute lymphoblastic leukemia cells. Oncogene 2013; 32:5602-13. [PMID: 23975424 PMCID: PMC3898485 DOI: 10.1038/onc.2013.349] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2013] [Revised: 06/11/2013] [Accepted: 07/01/2013] [Indexed: 12/15/2022]
Abstract
Although the intensification of therapy for children with T-cell acute lymphoblastic leukemia (T-ALL) has substantially improved clinical outcomes, T-ALL remains an important challenge in pediatric oncology. Here, we report that the cooperative synergy between prostate apoptosis response factor-4 (Par-4) and THAP1 induces cell cycle and apoptosis regulator 1 (CCAR1) gene expression and cellular apoptosis in human T-ALL cell line Jurkat cells, CEM cells and primary cultured neoplastic T lymphocytes from children with T-ALL. Par-4 and THAP1 collaborated to activate the promoter of CCAR1 gene. Mechanistic investigations revealed that Par-4 and THAP1 formed a protein complex by the interaction of their carboxyl termini, and THAP1 bound to CCAR1 promoter though its zinc-dependent DNA-binding domain at amino terminus. Par-4/THAP1 complex and Notch3 competitively bound to CCAR1 promoter and competitively modulated alternative pre-mRNA splicing of CCAR1, which resulted in two different transcripts and played an opposite role in T-ALL cell survival. Despite Notch3 induced a shift splicing from the full-length isoform toward a shorter form of CCAR1 mRNA by splicing factor SRp40 and SRp55, Par-4/THAP1 complex strongly antagonized this inductive effect. Our finding revealed a mechanistic rationale for Par-4/THAP1-induced apoptosis in T-ALL cells that would be of benefit to develop a new therapy strategy for T-ALL.
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WT1 promotes cell proliferation in non-small cell lung cancer cell lines through up-regulating cyclin D1 and p-pRb in vitro and in vivo. PLoS One 2013; 8:e68837. [PMID: 23936312 PMCID: PMC3731304 DOI: 10.1371/journal.pone.0068837] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2012] [Accepted: 06/04/2013] [Indexed: 12/12/2022] Open
Abstract
The Wilms’ tumor suppressor gene (WT1) has been identified as an oncogene in many malignant diseases such as leukaemia, breast cancer, mesothelioma and lung cancer. However, the role of WT1 in non-small-cell lung cancer (NSCLC) carcinogenesis remains unclear. In this study, we compared WT1 mRNA levels in NSCLC tissues with paired corresponding adjacent tissues and identified significantly higher expression in NSCLC specimens. Cell proliferation of three NSCLC cell lines positively correlated with WT1 expression; moreover, these associations were identified in both cell lines and a xenograft mouse model. Furthermore, we demonstrated that up-regulation of Cyclin D1 and the phosphorylated retinoblastoma protein (p-pRb) was mechanistically related to WT1 accelerating cells to S-phase. In conclusion, our findings demonstrated that WT1 is an oncogene and promotes NSCLC cell proliferation by up-regulating Cyclin D1 and p-pRb expression.
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Pereira MC, de Bessa-Garcia SA, Burikhanov R, Pavanelli AC, Antunes L, Rangnekar VM, Nagai MA. Prostate apoptosis response-4 is involved in the apoptosis response to docetaxel in MCF-7 breast cancer cells. Int J Oncol 2013; 43:531-8. [PMID: 23760770 PMCID: PMC4035780 DOI: 10.3892/ijo.2013.1983] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2013] [Accepted: 05/02/2013] [Indexed: 11/30/2022] Open
Abstract
Experimental evidence indicates that prostate apoptosis response-4 (Par-4, also known as PAWR) is a key regulator of cancer cell survival and may be a target for cancer-selective targeted therapeutics. Par-4 was first identified in prostate cancer cells undergoing apoptosis. Both intracellular and extracellular Par-4 have been implicated in apoptosis. Relatively little is known about the role of Par-4 in breast cancer cell apoptosis. In this study, we sought to investigate the effects of Par-4 expression on cell proliferation, apoptosis and drug sensitivity in breast cancer cells. MCF-7 cells were stably transfected with expression vectors for Par-4, or transiently transfected with siRNA for Par-4 knockdown. Cell proliferation assays were performed using MTT and apoptosis was evaluated using acridine orange staining, fluorescence microscopy and flow cytometry. Par-4 overexpression reduced MCF-7 proliferation rates. Conversely, Par-4 knockdown led to increased MCF-7 proliferation. Par-4 downregulation also led to increased BCL-2 and reduced BID expression. Par-4 overexpression did not affect the cell cycle profile. However, MCF-7 cells with increased Par-4 expression showed reduced ERK phosphorylation, suggesting that the inhibition of cell proliferation promoted by Par-4 may be mediated by the MAPK/ERK1/2 pathway. MCF-7 cells with increased Par-4 expression showed a marginal increase in early apoptotic cells. Importantly, we found that Par-4 expression modulates apoptosis in response to docetaxel in MCF7 breast cancer cells. Par-4 exerts growth inhibitory effects on breast cancer cells and chemosensitizes them to docetaxel.
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Affiliation(s)
- Michelly C Pereira
- Discipline of Oncology, Department of Radiology and Oncology, Faculty of Medicine, University of São Paulo, CEP 01246-903, São Paulo, Brazil
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Yang K, Shen J, Xie YQ, Lin YW, Qin J, Mao QQ, Zheng XY, Xie LP. Promoter-targeted double-stranded small RNAs activate PAWR gene expression in human cancer cells. Int J Biochem Cell Biol 2013; 45:1338-46. [PMID: 23583662 DOI: 10.1016/j.biocel.2013.03.022] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2012] [Revised: 03/09/2013] [Accepted: 03/18/2013] [Indexed: 10/27/2022]
Abstract
RNA activation is a promising discovery that promoter-targeted double-stranded small RNAs, termed small activating RNAs (saRNAs), can induce gene expression, which represents a novel approach to gene over-expression without traditional vector-based systems. PAWR is a tumor suppressing gene essential for apoptosis and a cancer-selective target for cancer therapeutics. Here our study identified synthetic saRNAs that could activate the expression of PAWR in human cancer cells. Functional analysis of PAWR induction revealed that saRNA treatment induced growth inhibition and apoptosis of cancer cells, and predictably modulated the expression of known downstream target gene Bcl-2. New functional saRNAs can also be harvested by one or two-base shifting of the original target sites. Chromatin immunoprecipitation assays indicated that activation of PAWR is accompanied by reduced dimethylation at histone H3K9 and increased dimethylation at histone H3K4. Moreover, the existence of transcripts in PAWR promoter was detected but its relationship with RNA activation needs more lucubration. These data have enlarged the gene pool of RNAa and hold great promise as an alternative for PAWR-targeted therapeutics.
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Affiliation(s)
- Kai Yang
- Department of Urology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310003, PR China
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29
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Abstract
INTRODUCTION Despite extensive research, cancer continues to be a leading cause of death worldwide and is expected to continue to rise as a result of an aging population. Therefore, new therapies are constantly being developed. Par-4 is a naturally occurring tumor suppressor protein that is capable of inducing apoptosis in cancer, but not normal cells. For this reason, Par-4 offers an attractive target for development of cancer therapy, particularly of difficult to treat cancers. AREAS COVERED The mechanisms by which Par-4 induces cell death are summarized. The ways that Par-4 is controlled in cancer cells are discussed. We discuss how different research groups have developed ways to overexpress and/or activate Par-4 in vitro and in vivo. The studies described demonstrate that when Par-4 levels and/or activity are increased, susceptibility to apoptosis is enhanced and tumor growth is inhibited. EXPERT OPINION Par-4 is a promising therapeutic protein that can be overexpressed and/or activated to induce apoptosis in a cancer-selective manner. This cancer selectivity is important given that the side-effects of chemotherapeutics can be as debilitating as cancer itself. However, there are key issues that need to be addressed to optimize the effects of Par-4 in patients.
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Affiliation(s)
- Rosalyn B Irby
- Penn State Hershey Cancer Institute, 500 University Drive, Hershey, PA 17033, USA.
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30
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Wang G, Dinkins M, He Q, Zhu G, Poirier C, Campbell A, Mayer-Proschel M, Bieberich E. Astrocytes secrete exosomes enriched with proapoptotic ceramide and prostate apoptosis response 4 (PAR-4): potential mechanism of apoptosis induction in Alzheimer disease (AD). J Biol Chem 2012; 287:21384-95. [PMID: 22532571 DOI: 10.1074/jbc.m112.340513] [Citation(s) in RCA: 280] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Amyloid protein is well known to induce neuronal cell death, whereas only little is known about its effect on astrocytes. We found that amyloid peptides activated caspase 3 and induced apoptosis in primary cultured astrocytes, which was prevented by caspase 3 inhibition. Apoptosis was also prevented by shRNA-mediated down-regulation of PAR-4, a protein sensitizing cells to the sphingolipid ceramide. Consistent with a potentially proapoptotic effect of PAR-4 and ceramide, astrocytes surrounding amyloid plaques in brain sections of the 5xFAD mouse (and Alzheimer disease patient brain) showed caspase 3 activation and were apoptotic when co-expressing PAR-4 and ceramide. Apoptosis was not observed in astrocytes with deficient neutral sphingomyelinase 2 (nSMase2), indicating that ceramide generated by nSMase2 is critical for amyloid-induced apoptosis. Antibodies against PAR-4 and ceramide prevented amyloid-induced apoptosis in vitro and in vivo, suggesting that apoptosis was mediated by exogenous PAR-4 and ceramide, potentially associated with secreted lipid vesicles. This was confirmed by the analysis of lipid vesicles from conditioned medium showing that amyloid peptide induced the secretion of PAR-4 and C18 ceramide-enriched exosomes. Exosomes were not secreted by nSMase2-deficient astrocytes, indicating that ceramide generated by nSMase2 is critical for exosome secretion. Consistent with the ceramide composition in amyloid-induced exosomes, exogenously added C18 ceramide restored PAR-4-containing exosome secretion in nSMase2-deficient astrocytes. Moreover, isolated PAR-4/ceramide-enriched exosomes were taken up by astrocytes and induced apoptosis in the absence of amyloid peptide. Taken together, we report a novel mechanism of apoptosis induction by PAR-4/ceramide-enriched exosomes, which may critically contribute to Alzheimer disease.
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Affiliation(s)
- Guanghu Wang
- Program in Developmental Neurobiology, Institute of Molecular Medicine and Genetics, Medical College of Georgia, Georgia Health Sciences University, Augusta, Georgia 30912, USA
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31
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Gonzalez D, Thackeray H, Lewis PD, Mantani A, Brook N, Ahuja K, Margara R, Joels L, White JO, Conlan RS. Loss of WT1 expression in the endometrium of infertile PCOS patients: a hyperandrogenic effect? J Clin Endocrinol Metab 2012; 97:957-66. [PMID: 22238403 DOI: 10.1210/jc.2011-2366] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
CONTEXT In fertile patients the endometrial Wilms tumor suppressor gene (WT1) is expressed during the window of implantation. Polycystic ovary syndrome (PCOS) patients suffer from hyperandrogenemia and infertility and have elevated endometrial androgen receptor (AR) expression. WT1 is known to be down-regulated by AR. Therefore, the expression of WT1 and its targets may be altered in PCOS endometrium. OBJECTIVE The objective of the study was to assess the expression and regulation of WT1 and selected downstream targets in secretory endometrium from ovulatory PCOS (ovPCOS) and fertile women. DESIGN AND PATIENTS Endometrial samples were obtained from 25 ovPCOS and 25 fertile patients. MAIN OUTCOME MEASURE Endometrial expression of WT1 and selected downstream targets were assessed by immunohistochemistry and RT-PCR. The androgen effect on WT1 expression was determined in vitro by immunoblots and RT-PCR. The expression of WT1 and its targets was quantified in fertile and ovPCOS stromal cells in the presence of androgens by RT-PCR. Caspase-3/7 activity was measured to evaluate sensitivity to drug-induced apoptosis. RESULTS WT1 expression was down-regulated in secretory-phase ovPCOS endometrium. Stromal expression of Bcl-2 and p27 was higher, and epidermal growth factor receptor was lower in ovPCOS than in fertile patients. Endometrial stromal expression of WT1, Bcl-2, Bcl-2-associated X protein, and β-catenin was regulated by androgens. Apoptosis levels were reduced in ovPCOS samples and androgen-treated fertile samples. CONCLUSION WT1 expression is down-regulated in ovPCOS endometrium during the window of implantation. Androgens regulate the expression of WT1 and its targets during endometrial decidualization. The altered balance between WT1 and AR in the endometrium of PCOS patients may jeopardize the success of decidualization and endometrial receptivity.
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Affiliation(s)
- D Gonzalez
- Institute of Life Science, Swansea University, College of Medicine, and Singleton Hospital, Swansea SA2 8PP, United Kingdom
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Zapata-Benavides P, Manilla-Muñoz E, Zamora-Avila DE, Saavedra-Alonso S, Franco-Molina MA, Trejo-Avila LM, Davalos-Aranda G, Rodríguez-Padilla C. WT1 silencing by RNAi synergizes with chemotherapeutic agents and induces chemosensitization to doxorubicin and cisplatin in B16F10 murine melanoma cells. Oncol Lett 2012; 3:751-755. [PMID: 22740987 DOI: 10.3892/ol.2012.578] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2011] [Accepted: 11/17/2011] [Indexed: 12/20/2022] Open
Abstract
The Wilm's tumor gene (WT1), encoding a transcription factor that modulates the expression of certain genes that are involved in proliferation and apoptosis, is overexpressed in numerous solid tumors. WT1 is important for cell proliferation and in the diagnosis of melanoma. The objectives of this study were to investigate whether WT1 silencing is capable of synergizing with chemotherapeutic agents and whether this silencing is capable of sensitizing cancer cells to doxorubicin and cisplatin in the B16F10 murine melanoma cell line. In the present study, B16F10 cells were simultaneously treated with median lethal doses (LD50s) of WT1-1 or WT1-2 small hairpin RNAs (shRNAs) and chemotherapeutic agents. A total of 24 h post-transfection, a [3-(4,5-dimethylthiazol-2yl)-2,5- diphenyl tetrazolium bromide assay] MTT assay was performed. To determine whether shRNA interference (shRNAi) is capable of sensitizing B16F10 cells to chemotherapeutic agents, cells were transfected with an LD50 of each of the recombinant plasmids, treated with varying concentrations of doxorubicin or cisplatin 24 h post-transfection, and analyzed 48 h later for inhibition of cell proliferation using the MTT assay. We observed that WT1-RNAi and the two chemotherapeutic agents acted synergistically to inhibit B16F10 cell proliferation. The greatest inhibition of cell proliferation was observed with the WT1-2/cisplatin (91%) and WT1-1/cisplatin combinations (85%). WT1 silencing using shRNAi induced the chemosensitization of cells to doxorubicin and cisplatin, with the greatest inhibition (85%) of cell proliferation being observed in the cells treated with the WT1-2/cisplatin 6 ng/µl combination. Our results provide direct evidence that WT1 gene silencing has a synergistic effect with chemotherapeutic drugs and sensitizes B16F10 melanoma cells to doxorubicin and cisplatin. This suggests that these combination strategies are potentially utilized in melanoma therapy.
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Affiliation(s)
- Pablo Zapata-Benavides
- Laboratorio de Inmunología y Virología, Departamento de Microbiología e Inmunología, Facultad de Ciencias Biológicas de la Universidad Autónoma de Nuevo León, San Nicolás de los Garza, N.L. México
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Prostate apoptosis response 4 (Par-4), a novel substrate of caspase-3 during apoptosis activation. Mol Cell Biol 2011; 32:826-39. [PMID: 22184067 DOI: 10.1128/mcb.06321-11] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Prostate apoptosis response 4 (Par-4) is a ubiquitously expressed proapoptotic tumor suppressor protein. Here, we show for the first time, that Par-4 is a novel substrate of caspase-3 during apoptosis. We found that Par-4 is cleaved during cisplatin-induced apoptosis in human normal and cancer cell lines. Par-4 cleavage generates a C-terminal fragment of ~25 kDa, and the cleavage of Par-4 is completely inhibited by a caspase-3 inhibitor, suggesting that caspase-3 is directly involved in the cleavage of Par-4. Caspase-3-deficient MCF-7 cells do not show Par-4 cleavage in response to cisplatin treatment, and restoration of caspase-3 in MCF-7 cells produces a decrease in Par-4 levels, with the appearance of a cleaved fragment. Additionally, knockdown of Par-4 reduces caspase-3 activation and apoptosis induction. Site-directed mutagenesis reveals that Par-4 cleavage by caspase-3 occurs at an unconventional site, EEPD(131)↓G. Interestingly, overexpression of wild-type Par-4 but not the Par-4 D131A mutant sensitizes cells to cisplatin-induced apoptosis. Upon caspase-3 cleavage, the cleaved fragment of Par-4 accumulates in the nucleus and displays increased apoptotic activity. Overexpression of the cleaved fragment of Par-4 inhibits IκBα phosphorylation and blocks NF-κB nuclear translocation. We have identified a novel specific caspase-3 cleavage site in Par-4, and the cleaved fragment of Par-4 retains proapoptotic activity.
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Abstract
Wilms' tumour is a paediatric malignancy of the kidneys and is one of the most common solid childhood cancers. The Wilms' tumour 1 protein (WT1) is a transcription factor that can either activate or repress genes involved in growth, apoptosis and differentiation. It is frequently mutated or aberrantly expressed in Wilms' tumour, where the wild type protein would normally act as a tumour suppressor. Several studies, however, have found that wild type WT1 acts as an oncogene in adult tumours, primarily through the inhibition of apoptosis. The expression of WT1 correlates with the aggressiveness of several adult cancers, and its continued expression following treatment is indicative of a poor outcome.We recently found that the treatment of tumour cell lines with cytotoxic drugs leads to the cleavage of WT1 by the serine protease HtrA2. HtrA2 binds to a specific region of WT1, the suppression domain, and then cleaves WT1 at multiple sites. The HtrA2-mediated proteolysis of WT1 leads to its removal from gene promoter regions and changes in gene expression. Cleavage of WT1 by HtrA2 enhances apoptosis. This event is advantageous to the treatment of adult tumours where WT1 acts as an oncogene. However, when WT1 is acting as a tumour suppressor in paediatric malignancies, proteolysis by HtrA2 would be antagonistic to therapy.
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Affiliation(s)
- Jörg Hartkamp
- Faculty of Life Sciences, The Michael Smith Building, University of Manchester, Manchester, UK
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Zhuang D, Liu Y, Mao Y, Gao L, Zhang H, Luan S, Huang F, Li Q. TMZ-induced PrPc/par-4 interaction promotes the survival of human glioma cells. Int J Cancer 2011; 130:309-18. [PMID: 21328340 DOI: 10.1002/ijc.25985] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2010] [Accepted: 01/26/2011] [Indexed: 01/12/2023]
Abstract
Malignant gliomas recur even after extensive surgery and chemo-radiotherapy. Although a relatively novel chemotherapeutic agent, temozolomide (TMZ), has demonstrated promising activity against gliomas, the effects last only a few months and drug resistance develops thereafter in many cases. It has been acknowledged that glioma cells respond to TMZ treatment by undergoing G2/M arrest, but not apoptosis. Here we demonstrate a phase-specific chemotherapy resistance due to cellular prion protein (PrPc) in human glioma cells upon TMZ treatment. TMZ-induced G2/M-arrested cultures show an upregulation of PrPc expression and are more resistant, whereas G1/S-phase cells that show decreased levels of PrPc are more sensitive to apoptosis. Furthermore, an investigation into the biological significance of PrPc association with par-4 provided the first evidence of a relationship between the endogenous levels of PrPc and the resistance of glioma cells to the apoptotic effects of TMZ. Upon TMZ treatment, PrPc exerts its antiapoptotic activity by inhibiting PKA-mediated par-4 phosphorylation that are important for par-4 activation, nuclear entry and initiation of apoptosis. In context with cell cycle-dependent responses to chemotherapy, the data from this study suggest the possibility of exploiting the PrPc-dependent pathway to improve the efficacy of TMZ-based regimen for patients with gliomas.
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Affiliation(s)
- Dongxiao Zhuang
- Department of Neurosurgery, HuaShan Hospital, Fudan University, Shanghai, People's Republic of China
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Rossi V, Bellastella G, De Rosa C, Abbondanza C, Visconti D, Maione L, Chieffi P, Della Ragione F, Prezioso D, De Bellis A, Bellastella A, Sinisi AA. Raloxifene induces cell death and inhibits proliferation through multiple signaling pathways in prostate cancer cells expressing different levels of estrogen receptor α and β. J Cell Physiol 2011; 226:1334-9. [PMID: 20945400 DOI: 10.1002/jcp.22461] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Raloxifene (RAL), a selective estrogen receptor (ER) modulator (SERM) seems to induce apoptosis in both androgen-dependent and -independent prostate cell (PC) lines via activation of ERβ and an antagonistic effect on ERα. In this study, we evaluated the effects of RAL on epithelial PC growth using the two following in vitro models: the androgen-dependent cell line EPN which expressed both ERs; and a stabilized epithelial cell line derived from a prostate cancer specimen (CPEC), which expressed low levels of ERβ and lacked ERα. In EPN cells, there was an increase in the pre-G1 apoptotic peak and a reduction in the S phase of the cell cycle with G0/G1 arrest after E2 or RAL treatment; bcl-2 mRNA and Bcl-2 protein levels were significantly reduced, while activated caspase-3 and Par-4 levels increased significantly after either E2 or RAL treatment; in addition, c-myc transcript was inhibited after 10(-6) M RAL treatment. A dose-dependent increase of metallothionein II gene RNA level was also induced by RAL in EPN. In CPEC, there was only a weak apoptotic peak associated with caspase-3 activation and Par-4 increase after either E2 or RAL treatment; while c-myc transcript level increased. RAL induced a rapid but transient phosphorylation of ERK 1/2 in EPN cells but generated a sustained effect in CPEC. These findings suggest that RAL effects on PC growth control in vitro are cell-specific, depending on ERβ or ERβ/ERα relative expression levels. Moreover, this study demonstrated that RAL affected both transcriptional regulation and non-genomic signals, which resulted in the modulation of multiple signaling pathways of apoptosis and of cell cycle progression.
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Affiliation(s)
- V Rossi
- Dipartimento di Internistica Clinica e Sperimentale, Sezione di Endocrinologia ed Andrologia Medica, Universita' Federico II, Napoli, Italy
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Abstract
Keeping in view the fact that the most pathognomonic feature of Alzheimer's disease is the abnormal processing of neuronal cell membrane amyloid precursor protein accompanied by significantly elevated human serum and CSF levels of 24-hydroxycholesterol recognised widely as the specific endogenous ligand of Liver X receptor (LXR-α), the present study was addressed to explore the epigenomic-pathway (if any) that connects LXR-α activation with the genes recognised to be involved in the regulation of aberrant Abeta production leading to the generation of toxic and inflammatory mediators responsible for neuronal death. The results of such a study revealed that LXR-α activation by its specific endogenous or exogenous ligands within neuroblastoma cells resulted in the over-expression of PAR-4 gene accompanied by suppression of AATF gene through its inherent capacity to regulate genes coding for SREBP and NF-κB. Over-expression of PAR-4 gene was accompanied by aberrant Abeta production followed by ROS generation and subsequent death of neuroblastoma cells used in the present study as a cellular model for neurons. Further based upon these results, it was proposed that Abeta-induced heme oxygenase-1 can ensure cholesterol-oxidation to provide endogenous ligands for the sustained activation of neuronal LXR-α dependent epigenomic-pathway leading to neuronal death observed in Alzheimer's disease.
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Affiliation(s)
- Ashvinder Raina
- Department of Experimental Medicine and Biotechnology, Postgraduate Institute of Medical Education and Research, Chandigarh 160012, India
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Lee JW, Hsiao WT, Lee KF, Sheu LF, Hsu HY, Hsu LP, Su B, Lee MS, Hsu YC, Chang CH. Widespread expression of prostate apoptosis response-4 in nasopharyngeal carcinoma. Head Neck 2010; 32:877-85. [PMID: 19908316 DOI: 10.1002/hed.21282] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
BACKGROUND Prostate apoptosis response-4 (Par-4) augments apoptosis in various tumors, either during apoptotic insult or by ectopic overexpression. However, investigation of Par-4 expression in nasopharyngeal carcinoma (NPC) is lacking. METHODS Specimens from patients with NPC, hypopharyngeal carcinoma (HPC), or oral cavity cancer were examined for Par-4 expression using immunohistochemistry. NPC cell proliferation and apoptosis were analyzed using immunohistochemical staining for Ki67, B-cell lymphoma 2 (Bcl-2), and in situ terminal deoxyribonucleotidyl transferase (TdT)-mediated biotin-16-dUTP nick end-labeling (TUNEL) assay, respectively. RESULTS Par-4 was ubiquitously expressed in NPC biopsies (96.2%, 25/26) and was significantly higher than in HPC (47.6%, 50/105, p < .0001) and oral cavity cancers (38.7%, 12/31, p < .0001). Remarkably, apoptosis of NPC cells was absent and Par-4 expression was associated with obvious expression of Bcl-2 and Ki67 in all patients tested with NPC. CONCLUSIONS Immunohistochemistry results showed widespread expression of Par-4 in NPC and revealed sustainable proliferation of NPC cells regardless of Par-4 expression.
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Affiliation(s)
- Jeng-Woei Lee
- Institute of Life Science, College of Life Science, Tzu-Chi University, Hualien, Taiwan.
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Méndez-López LF, Zapata-Benavides P, Zavala-Pompa A, Aguado-Barrera ME, Pacheco-Calleros J, Rodríguez-Padilla C, Cerda-Flores RM, Cortés-Gutiérrez EI, Dávila-Rodríguez MI. Immunohistochemical analysis of prostate apoptosis response-4 (Par-4) in Mexican women with breast cancer: a preliminary study. Arch Med Res 2010; 41:261-8. [PMID: 20637369 DOI: 10.1016/j.arcmed.2010.05.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2010] [Accepted: 05/13/2010] [Indexed: 02/07/2023]
Abstract
BACKGROUND AND AIMS We undertook this study to compare the expression level of prostate apoptosis response-4 (Par-4) among patient outcome in two groups of women with breast cancer (short and long survival) and two groups without breast cancer (benign lesion and control). METHODS We included breast specimens with nonhistological abnormalities (eight samples) as a control group. Semiquantitative and quantitative analysis of immunohistochemical staining by image analysis software were used to study the intensity of Par-4 expression. Both methods produced similar results (p>0.05). RESULTS No significant expression of Par-4 was observed in normal breast tissue. Benign lesions and breast cancer tissue showed strong nuclear expression of Par-4, predominantly on epithelial cells and specifically in ductal cells. Par-4 expression was lower in myoepithelial cells and there was no appreciable stromal staining. Significantly less Par-4 reactivity was detected in tissue from patients with a short survival compared with patients with benign lesions and those with a long survival. CONCLUSIONS Our findings suggest that a lower expression level of Par-4 is related to an unfavorable prognosis. A larger prospective study of samples of all patient groups with a longer follow-up is needed to validate this finding.
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Affiliation(s)
- Luis Fernando Méndez-López
- División de Genética, Centro de Investigación Biomédica del Noreste, Instituto Mexicano del Seguro Social, Monterrey, Mexico
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Azmi AS, Philip PA, Zafar SF, Sarkar FH, Mohammad RM. PAR-4 as a possible new target for pancreatic cancer therapy. Expert Opin Ther Targets 2010; 14:611-20. [PMID: 20426700 DOI: 10.1517/14728222.2010.487066] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
IMPORTANCE OF THE FIELD Pancreatic cancer (PC) is a deadly disease that is intractable to currently available treatment regimens. Although well described in different tumors types, the importance of apoptosis inducer prostate apoptosis response-4 (Par-4) in PC has not been appreciated. PC is an oncogenic kras driven disease, which is known to downregulate Par-4. Therefore, this review highlights its significance and builds a strong case supporting the role of Par-4 as a possible therapeutic target in PC. AREAS COVERED IN THIS REVIEW Literature-based evidence spanning the last 15 years on Par-4 and its significance in PC. WHAT THE READER WILL GAIN This review provides comprehensive knowledge of the significance of Par-4 and its association with kras status in PC, along with the crosstalk with crucial resistance and survival molecules NF-kappaB and Bcl-2 that ultimately are responsible for the overall poor outcome of different therapeutic approaches in this disease. TAKE HOME MESSAGE Par-4 holds promise as a potential therapeutic target that can be induced by chemopreventive agents and small-molecule inhibitors either alone or in combination with standard chemotherapeutics leading to selective apoptosis in PC cells. It also acts as a chemosensitizer and therefore warrants further clinical investigations in this disease.
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Affiliation(s)
- Asfar S Azmi
- Department of Pathology, Wayne State University School of Medicine, Detroit, MI 48201, USA.
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Mehrotra A, Joshi K, Kaul D. E2F-1 RNomics is critical for reprogramming of cancer cells to quiescent state. Int J Cancer 2010; 127:849-58. [PMID: 20013804 DOI: 10.1002/ijc.25109] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The discovery of cooperativity between pRB and E2F greatly prompted various investigators to find how E2F biology contributes to oncogenesis. Although E2F family of transcription factors have been linked to proliferation, apoptosis and differentiation, yet no heed has been paid to understand the role of E2F biology in cellular quiescence. To understand the functional RNomics (regulation of gene transcription through RNA interference) of E2F-1 gene, 2 cancer cell lines, such as Jurkat exhibiting E2F-1 gene overamplification and Hela-229 exhibiting intrinsic downregulation of E2F-1 gene expression, were used in our study. E2F-1 gene knockdown via siRNA within Jurkat cells resulted in upregulation of genes characteristic of quiescence both translationally and transcriptionally, which was accompanied by downregulation of genes at both translational and transcriptional level involved in cell cycle progression and apoptosis. This genomic phenomenon also translated into ultrastructural and phenotypic features typical of quiescent state. These observed results in Jurkat cells were simulated by upregulation of E2F-1 gene in Hela-229 cells through the downregulation of miR 17-5p. This E2F-1-regulated pathway explained as to how Jurkat cells entered exclusively into quiescent state when E2F-1 was downregulated in these cells and how Hela-229 cells proliferate vigorously when E2F-1 was upregulated in such cells. Here, we propose a gene-regulatory pathway which the cell might be using in its entry into either quiescent or proliferative states. Furthermore, this pathway may be useful in designing strategies for the treatment of cancer in general and acute lymphoblastic leukemia in particular.
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Affiliation(s)
- Aanchal Mehrotra
- Department of Experimental Medicine and Biotechnology, Post Graduate Institute of Medical Education and Research, Chandigarh 160012, India
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Sipilä T, Kananen L, Greco D, Donner J, Silander K, Terwilliger JD, Auvinen P, Peltonen L, Lönnqvist J, Pirkola S, Partonen T, Hovatta I. An association analysis of circadian genes in anxiety disorders. Biol Psychiatry 2010; 67:1163-70. [PMID: 20122683 DOI: 10.1016/j.biopsych.2009.12.011] [Citation(s) in RCA: 72] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/29/2009] [Revised: 11/23/2009] [Accepted: 12/14/2009] [Indexed: 11/19/2022]
Abstract
BACKGROUND The mammalian circadian system is responsible for controlling daily oscillations in physiology and behavior. Circadian genes contribute to the sleep-wake cycle and mood, and because patients with anxiety disorder often suffer from sleep disturbances, we hypothesized that variants in circadian-clock-related genes might predispose to human anxiety disorders as well. We tested this hypothesis with a genetic association analysis. METHODS We analyzed 131 single nucleotide polymorphisms from 13 circadian-clock-related genes. The study sample consisted of 321 individuals diagnosed with an anxiety disorder and 653 matched healthy controls from a Finnish population-based cohort. RESULTS Single nucleotide polymorphisms in two genes showed some evidence for association to social phobia: in ARNTL2 rs2306073 (p = .0099) and in DRD2 rs7131056 (p = .0084). BCL2 rs12454712 (p = .0029) and DRD2 rs4245146 (p = .0010) showed evidence for association to generalized anxiety disorder, whereas rs2463107 (p = .0064) in PAWR and rs4245146 (p = .0029) in DRD2 showed evidence for association to the pooled group of all anxiety disorders. Findings in DRD2 became stronger when only anxiety disorder cases with comorbid alcohol use disorder were considered. CONCLUSIONS Genes contributing to circadian rhythms might also play a role in the genetic predisposition to anxiety disorders. In addition, our study provides further support for the association of DRD2 to comorbid anxiety and alcohol use disorder.
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Affiliation(s)
- Tessa Sipilä
- Research Program of Molecular Neurology, University of Helsinki, Helsinki, Finland
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Saegusa M, Hashimura M, Kuwata T, Okayasu I. Transcriptional regulation of pro-apoptotic Par-4 by NF-kappaB/p65 and its function in controlling cell kinetics during early events in endometrial tumourigenesis. J Pathol 2010; 221:26-36. [PMID: 20186924 DOI: 10.1002/path.2680] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Prostatic apoptosis response-4 (Par-4) was first identified in prostatic cancer cells that were induced to undergo apoptosis. Recently, Par-4 has been suggested to be a tumour suppressor gene that plays a role in the development of endometrial carcinomas (ECs), but the exact mechanism remains to be clarified. Here we examined gene activation signalling cascades and influence on cell kinetics during endometrial tumourigenesis. In normal endometrium, constitutively high levels of Par-4 expression were observed in epithelial cells through the menstrual cycle, in contrast to the transient up-regulation in stromal components in the menstrual stage, correlated positively with the phospho-p65 (pp65) status and apoptosis. In contrast, most ECs exhibited significant down-regulation as compared to normal endometrium, with positive links only to pp65 expression. In EC cell lines, transfection of the NF-kappaB subunit p65 led to transactivation of Par-4 through specific binding to its promoter region, in contrast to the suppression by active Akt, suggesting that the balance between the two signals may be important to determine Par-4 expression levels. In addition, transient overexpression of Par-4 resulted in the induction of not only apoptosis but also senescence, through changes in the expression of bcl-2 and p21$;{{\rm WAF1}}$, respectively. Together, these findings suggest that a signalling cascade involving sequential activation of NF-kappaB/p65 and Par-4 may participate in relatively early events of endometrial tumourigenesis, leading to modulation of cell kinetics including apoptosis and cell cycle progression.
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Affiliation(s)
- Makoto Saegusa
- Department of Pathology, Kitasato University School of Medicine, 1-15-1 Kitasato, Sagamihara, Kanagawa 228-8555, Japan.
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Wang BD, Kline CLB, Pastor DM, Olson TL, Frank B, Luu T, Sharma AK, Robertson G, Weirauch MT, Patierno SR, Stuart JM, Irby RB, Lee NH. Prostate apoptosis response protein 4 sensitizes human colon cancer cells to chemotherapeutic 5-FU through mediation of an NF kappaB and microRNA network. Mol Cancer 2010; 9:98. [PMID: 20433755 PMCID: PMC2883962 DOI: 10.1186/1476-4598-9-98] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2010] [Accepted: 04/30/2010] [Indexed: 01/07/2023] Open
Abstract
Background Diminished expression or activity of prostate apoptosis response protein 4 (Par-4) has been demonstrated in a number of cancers, although reports on Par-4 expression during colon cancer progression are lacking. An understanding of the molecular events in conjunction with the genetic networks affected by Par-4 is warranted. Results Colon cancer specimens derived from patients have significantly diminished expression of Par-4 mRNA relative to paired normal colon. Hence, the functional consequences of reintroducing Par-4 into HT29 colon cancer cells were assessed. Overexpression augmented the interaction of Par-4 with NFκB in the cytosol but not nucleus, and facilitated apoptosis in the presence of 5-fluorouracil (5-FU). Analogous findings were obtained when AKT1 pro-survival signaling was inhibited. Transcriptome profiling identified ~700 genes differentially regulated by Par-4 overexpression in HT29 cells. Nearly all Par-4-regulated genes were shown by promoter analysis to contain cis-binding sequences for NFκB, and meta-analysis of patient expression data revealed that one-third of these genes exist as a recurrent co-regulated network in colon cancer specimens. Sets of genes involved in programmed cell death, cell cycle regulation and interestingly the microRNA pathway were found overrepresented in the network. Noteworthy, Par-4 overexpression decreased NFκB occupancy at the promoter of one particular network gene DROSHA, encoding a microRNA processing enzyme. The resulting down-regulation of DROSHA was associated with expression changes in a cohort of microRNAs. Many of these microRNAs are predicted to target mRNAs encoding proteins with apoptosis-related functions. Western and functional analyses were employed to validate several predictions. For instance, miR-34a up-regulation corresponded with a down-regulation of BCL2 protein. Treating Par-4-overexpressing HT29 cells with a miR-34a antagomir functionally reversed both BCL2 down-regulation and apoptosis by 5-FU. Conversely, bypassing Par-4 overexpression by direct knockdown of DROSHA expression in native HT29 cells increased miR-34a expression and 5-FU sensitivity. Conclusion Our findings suggest that the initiation of apoptotic sensitivity in colon cancer cells can be mediated by Par-4 binding to NFκB in the cytoplasm with consequential changes in the expression of microRNA pathway components.
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Affiliation(s)
- Bi-Dar Wang
- Department of Pharmacology and Physiology, The George Washington University Medical Center, Washington, DC 20037, USA
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Zapata-Benavides P, Méndez-Vázquez JL, González-Rocha TR, Zamora-Avila DE, Franco-Molina MA, Garza-Garza R, Rodriguez-Padilla C. Expression of prostate apoptosis response (Par-4) is associated with progesterone receptor in breast cancer. Arch Med Res 2010; 40:595-9. [PMID: 20082875 DOI: 10.1016/j.arcmed.2009.08.007] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2008] [Accepted: 07/31/2009] [Indexed: 11/18/2022]
Abstract
BACKGROUND The prostate apoptosis response (Par-4) gene encodes a proapoptotic protein that selectively induces apoptosis in cancer cells after diverse apoptotic stimuli. Par-4 expression and its association with other biomarkers have not been reported in breast cancer. The purpose of this study was to determine Par-4 expression in breast cancer samples and its association with other biomarkers and clinical factors (T-stage, age, nodal status). METHODS Paraffin-embedded section samples of breast cancer were evaluated by immunohistochemical analysis to determine Par-4, estrogen receptor (ER), progesterone receptor (PgR), c-erbB2, Ki67, p53 and bcl-2 expression. The correlation between Par-4 and the other biomarkers and clinical factors was determined by multivariate analysis. RESULTS Thirty five percent (n=21) of samples were PAR-4 positive and 64.4% (n=38) were negative. The hormonal status was 64% ER positive (n=38), 35% ER-negative (n=21) and 40.7% PgR positive (n=24), 59.3% PgR negative (n=35). The majority (90%) of the samples presented clear cytoplasmic localization and a small portion (10%) was cytoplasmic and nuclear. Univariate analysis indicates that the Par-4 expression has a significant inverse association (p=0.04) only with expression of PgR and not with the other variables analyzed. Normal breast tissue analyzed was negative for Par-4 immunostaining. CONCLUSIONS Our results suggest that, in breast cancer, Par-4 plays a similar tumor suppressor gene role as reported in endometrial carcinoma.
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Affiliation(s)
- Pablo Zapata-Benavides
- Departamento de Inmunología y Virología, Universidad Autónoma de Nuevo León, San Nicolás de los Garza, México
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Vetterkind S, Lee E, Sundberg E, Poythress RH, Tao TC, Preuss U, Morgan KG. Par-4: a new activator of myosin phosphatase. Mol Biol Cell 2010; 21:1214-24. [PMID: 20130087 PMCID: PMC2847525 DOI: 10.1091/mbc.e09-08-0711] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
We show here for the first time that the pro-apoptotic protein Par-4 binds to and activates myosin phosphatase (MP). During agonist stimulation, Par-4 facilitates ZIPK targeting and inhibitory phosphorylation of MP, however, phosphorylation of Par-4 is required for MP inhibition. Our model presents Par-4 as an amplifier of the MP activity range. Myosin phosphatase (MP) is a key regulator of myosin light chain (LC20) phosphorylation, a process essential for motility, apoptosis, and smooth muscle contractility. Although MP inhibition is well studied, little is known about MP activation. We have recently demonstrated that prostate apoptosis response (Par)-4 modulates vascular smooth muscle contractility. Here, we test the hypothesis that Par-4 regulates MP activity directly. We show, by proximity ligation assays, surface plasmon resonance and coimmunoprecipitation, that Par-4 interacts with the targeting subunit of MP, MYPT1. Binding is mediated by the leucine zippers of MYPT1 and Par-4 and reduced by Par-4 phosphorylation. Overexpression of Par-4 leads to increased phosphatase activity of immunoprecipitated MP, whereas small interfering RNA knockdown of endogenous Par-4 significantly decreases MP activity and increases MYPT1 phosphorylation. LC20 phosphorylation assays demonstrate that overexpression of Par-4 reduces LC20 phosphorylation. In contrast, a phosphorylation site mutant, but not wild-type Par-4, interferes with zipper-interacting protein kinase (ZIPK)-mediated MP inhibition. We conclude from our results Par-4 operates through a “padlock” model in which binding of Par-4 to MYPT1 activates MP by blocking access to the inhibitory phosphorylation sites, and inhibitory phosphorylation of MYPT1 by ZIPK requires “unlocking” of Par-4 by phosphorylation and displacement of Par-4 from the MP complex.
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Affiliation(s)
- Susanne Vetterkind
- Department of Health Sciences, Sargent College of Health and Rehabilitation Sciences, Boston University, Boston, MA 02215, USA
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Burikhanov R, Zhao Y, Goswami A, Qiu S, Schwarze SR, Rangnekar VM. The tumor suppressor Par-4 activates an extrinsic pathway for apoptosis. Cell 2009; 138:377-88. [PMID: 19632185 DOI: 10.1016/j.cell.2009.05.022] [Citation(s) in RCA: 177] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2008] [Revised: 01/14/2009] [Accepted: 05/01/2009] [Indexed: 12/12/2022]
Abstract
Prostate apoptosis response-4 (Par-4) is a proapoptotic protein with intracellular functions in the cytoplasm and nucleus. Unexpectedly, we noted Par-4 protein is spontaneously secreted by normal and cancer cells in culture, and by Par-4 transgenic mice that are resistant to spontaneous tumors. Short exposure to endoplasmic reticulum (ER) stress-inducing agents further increased cellular secretion of Par-4 by a brefeldin A-sensitive pathway. Secretion occurred independently of caspase activation and apoptosis. Interestingly, extracellular Par-4 induced apoptosis by binding to the stress response protein, glucose-regulated protein-78 (GRP78), expressed at the surface of cancer cells. The interaction of extracellular Par-4 and cell surface GRP78 led to apoptosis via ER stress and activation of the FADD/caspase-8/caspase-3 pathway. Moreover, apoptosis inducible by TRAIL, which also exerts cancer cell-specific effects, is dependent on extracellular Par-4 signaling via cell surface GRP78. Thus, Par-4 activates an extrinsic pathway involving cell surface GRP78 receptor for induction of apoptosis.
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Affiliation(s)
- Ravshan Burikhanov
- Department of Radiation Medicine, University of Kentucky, Lexington, KY 40536, USA
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Boosen M, Vetterkind S, Kubicek J, Scheidtmann KH, Illenberger S, Preuss U. Par-4 is an essential downstream target of DAP-like kinase (Dlk) in Dlk/Par-4-mediated apoptosis. Mol Biol Cell 2009; 20:4010-20. [PMID: 19625447 DOI: 10.1091/mbc.e09-02-0173] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Prostate apoptosis response-4 (Par-4) was initially identified as a gene product up-regulated in prostate cancer cells undergoing apoptosis. In rat fibroblasts, coexpression of Par-4 and its interaction partner DAP-like kinase (Dlk, which is also known as zipper-interacting protein kinase [ZIPK]) induces relocation of the kinase from the nucleus to the actin filament system, followed by extensive myosin light chain (MLC) phosphorylation and induction of apoptosis. Our analyses show that the synergistic proapoptotic effect of Dlk/Par-4 complexes is abrogated when either Dlk/Par-4 interaction or Dlk kinase activity is impaired. In vitro phosphorylation assays employing Dlk and Par-4 phosphorylation mutants carrying alanine substitutions for residues S154, T155, S220, or S249, respectively, identified T155 as the major Par-4 phosphorylation site of Dlk. Coexpression experiments in REF52.2 cells revealed that phosphorylation of Par-4 at T155 by Dlk was essential for apoptosis induction in vivo. In the presence of the Par-4 T155A mutant Dlk was partially recruited to actin filaments but resided mainly in the nucleus. Consequently, apoptosis was not induced in Dlk/Par-4 T155A-expressing cells. In vivo phosphorylation of Par-4 at T155 was demonstrated with a phospho-specific Par-4 antibody. Our results demonstrate that Dlk-mediated phosphorylation of Par-4 at T155 is a crucial event in Dlk/Par-4-induced apoptosis.
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Affiliation(s)
- Meike Boosen
- Institute of Genetics, University of Bonn, D-53117 Bonn, Germany
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Vivas-Mejía PE, Ozpolat B, Chen X, Lopez-Berestein G. Downregulation of the c-MYC target gene, peroxiredoxin III, contributes to arsenic trioxide-induced apoptosis in acute promyelocytic leukemia. Int J Cancer 2009; 125:264-75. [PMID: 19408305 PMCID: PMC10166086 DOI: 10.1002/ijc.24341] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Arsenic trioxide (ATO) induces differentiation and apoptosis in acute promyelocytic leukemia (APL). Several reports indicate that in APL cells apoptosis occurs mainly by a mechanism that involves the inhibition of glutathione peroxidase, one of the enzymes that regulates mitochondrial levels of H(2)O(2). Peroxiredoxin (Prx) III, a c-MYC target gene, is also a mitochondria-specific H(2)O(2)-scavenger enzyme. We studied here the role of Prx III during ATO-induced apoptosis in APL-derived NB4 cells, since these cells express high levels of Prx III. The protein and mRNA levels of Prx III decreased during ATO-induced apoptosis of NB4 cells. The downregulation of Prx III occurred before reactive oxygen species accumulation, reduction in the mitochondrial membrane potential and apoptosis. Depletion of Prx III enhanced mitochondrial-dependent apoptosis events. In contrast, overexpression of Prx III led to reduced levels of ATO-induced apoptosis. c-MYC was also downregulated in ATO-treated NB4 cells. Furthermore, depletion of c-MYC also reduced the Prx-III expression levels. Finally chromatin immunoprecipitation and luciferase reporter assays confirmed that downregulation of Prx-III was caused by the reduction of c-MYC levels during ATO-induced apoptosis of NB4 cells. These findings demonstrate a novel apoptotic-response pathway whereby downregulation of Prx-III potentiates ATO-induced apoptosis in APL cells.
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Affiliation(s)
- Pablo E Vivas-Mejía
- Department of Experimental Therapeutics, University of Texas, MD Anderson Cancer Center, Houston, TX 77030, USA
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Fujii YR. Oncoviruses and Pathogenic MicroRNAs in Humans. Open Virol J 2009; 3:37-51. [PMID: 19920887 PMCID: PMC2778015 DOI: 10.2174/1874357900903010037] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2009] [Revised: 03/19/2009] [Accepted: 03/24/2009] [Indexed: 12/19/2022] Open
Abstract
For disease prognosis, the functional significance of the oncoviral integration locus in oncogenesis has remained enigmatic. The locus encodes several transcripts without protein products, but microRNAs (miRNAs) have recently been identified from a common oncoviral integration locus. miRNA is an endogenous, non-coding small RNA by which gene expression is suppressed. Although miRNA genes, such as let-7 in the nematode, have orthologs among animals, the relationship between miRNAs and tumorigenesis or tumor suppression has been mainly discovered in several human cancers. On the contrary, this review clearly demonstrates the potential for human tumorigenesis of both miRNA genes from oncoviral integration sites and other cellular onco-microRNA genes, and we conclude that alteration of the miRNA profile of cells can be defined as tumorigenic or tumor suppressive. Thus, we explain here that virally-pathogenic miRNAs could also be partly responsible for oncogenesis or oncogene suppression to confirm' the RNA wave', with the miRNAs hypothesized as a mobile and functional genetic element.
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