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Cabezas F, Farfán P, Marzolo MP. Participation of the SMAD2/3 signalling pathway in the down regulation of megalin/LRP2 by transforming growth factor beta (TGF-ß1). PLoS One 2019; 14:e0213127. [PMID: 31120873 PMCID: PMC6532859 DOI: 10.1371/journal.pone.0213127] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Accepted: 05/08/2019] [Indexed: 12/19/2022] Open
Abstract
Megalin/LRP2 is a receptor that plays important roles in the physiology of several organs, such as kidney, lung, intestine, and gallbladder and also in the physiology of the nervous system. Megalin expression is reduced in diseases associated with fibrosis, including diabetic nephropathy, hepatic fibrosis and cholelithiasis, as well as in some breast and prostate cancers. One of the hallmarks of these conditions is the presence of the cytokine transforming growth factor beta (TGF-ß). Although TGF-ß has been implicated in the reduction of megalin levels, the molecular mechanism underlying this regulation is not well understood. Here, we show that treatment of two epithelial cell lines (from kidney and gallbladder) with TGF-ß1 is associated with decreased megalin mRNA and protein levels, and that these effects are reversed by inhibiting the TGF-ß1 type I receptor (TGF-ßRI). Based on in silico analyses, the two SMAD-binding elements (SBEs) in the megalin promoter are located at positions -57 and -605. Site-directed mutagenesis of the SBEs and chromatin immunoprecipitation (ChIP) experiments revealed that SMAD2/3 transcription factors interact with SBEs. Both the presence of SMAD2/3 and intact SBEs were associated with repression of the megalin promoter, in the absence as well in the presence of TGF-ß1. Also, reduced megalin expression and promoter activation triggered by high concentration of albumin are dependent on the expression of SMAD2/3. Interestingly, the histone deacetylase inhibitor Trichostatin A (TSA), which induces megalin expression, reduced the effects of TGF-ß1 on megalin mRNA levels. These data show the significance of TGF-ß and the SMAD2/3 signalling pathway in the regulation of megalin and explain the decreased megalin levels observed under conditions in which TGF-ß is upregulated, including fibrosis-associated diseases and cancer.
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Affiliation(s)
- Felipe Cabezas
- Laboratorio de Tráfico Intracelular y Señalización, Departamento de Biología Celular y Molecular, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Pamela Farfán
- Laboratorio de Tráfico Intracelular y Señalización, Departamento de Biología Celular y Molecular, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - María-Paz Marzolo
- Laboratorio de Tráfico Intracelular y Señalización, Departamento de Biología Celular y Molecular, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
- * E-mail:
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Komissarov AA, Rahman N, Lee YCG, Florova G, Shetty S, Idell R, Ikebe M, Das K, Tucker TA, Idell S. Fibrin turnover and pleural organization: bench to bedside. Am J Physiol Lung Cell Mol Physiol 2018; 314:L757-L768. [PMID: 29345198 DOI: 10.1152/ajplung.00501.2017] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Recent studies have shed new light on the role of the fibrinolytic system in the pathogenesis of pleural organization, including the mechanisms by which the system regulates mesenchymal transition of mesothelial cells and how that process affects outcomes of pleural injury. The key contribution of plasminogen activator inhibitor-1 to the outcomes of pleural injury is now better understood as is its role in the regulation of intrapleural fibrinolytic therapy. In addition, the mechanisms by which fibrinolysins are processed after intrapleural administration have now been elucidated, informing new candidate diagnostics and therapeutics for pleural loculation and failed drainage. The emergence of new potential interventional targets offers the potential for the development of new and more effective therapeutic candidates.
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Affiliation(s)
- Andrey A Komissarov
- Department of Cellular and Molecular Biology, The University of Texas Health Science Center at Tyler , Tyler, Texas
| | - Najib Rahman
- Oxford Pleural Unit and Oxford Respiratory Trials Unit, University of Oxford, Churchill Hospital; and National Institute of Health Research Biomedical Research Centre , Oxford , United Kingdom
| | - Y C Gary Lee
- Department of Respiratory Medicine, Sir Charles Gairdner Hospital; Pleural Medicine Unit, Institute for Respiratory Health , Perth ; School of Medicine and Pharmacology, University of Western Australia , Perth , Australia
| | - Galina Florova
- Department of Cellular and Molecular Biology, The University of Texas Health Science Center at Tyler , Tyler, Texas
| | - Sreerama Shetty
- Department of Cellular and Molecular Biology, The University of Texas Health Science Center at Tyler , Tyler, Texas
| | - Richard Idell
- Department of Behavioral Health, Child and Adolescent Psychiatry, The University of Texas Health Science Center at Tyler , Tyler, Texas
| | - Mitsuo Ikebe
- Department of Cellular and Molecular Biology, The University of Texas Health Science Center at Tyler , Tyler, Texas
| | - Kumuda Das
- Department of Translational and Vascular Biology, The University of Texas Health Science Center at Tyler , Tyler, Texas
| | - Torry A Tucker
- Department of Cellular and Molecular Biology, The University of Texas Health Science Center at Tyler , Tyler, Texas
| | - Steven Idell
- Department of Cellular and Molecular Biology, The University of Texas Health Science Center at Tyler , Tyler, Texas
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Popowicz N, Idell S, Lee YG. Pathogenesis of pleural infection: A complex warfare. Respirology 2017; 23:8-9. [DOI: 10.1111/resp.13171] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2017] [Accepted: 08/22/2017] [Indexed: 11/27/2022]
Affiliation(s)
- Natalia Popowicz
- Department of Respiratory Medicine; Sir Charles Gairdner Hospital; Perth WA Australia
- Pleural Medicine Unit; Institute for Respiratory Health; Perth WA Australia
- School of Medicine and Pharmacology; University of Western Australia; Perth WA Australia
| | - Steven Idell
- Department of Cellular and Molecular Biology and Texas Lung Injury Institute; The University of Texas Health Science Center at Tyler; Tyler TX USA
| | - Y.C. Gary Lee
- Department of Respiratory Medicine; Sir Charles Gairdner Hospital; Perth WA Australia
- Pleural Medicine Unit; Institute for Respiratory Health; Perth WA Australia
- School of Medicine and Pharmacology; University of Western Australia; Perth WA Australia
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Chang YC, Hsiao YM, Wu MF, Ou CC, Lin YW, Lue KH, Ko JL. Interruption of lung cancer cell migration and proliferation by fungal immunomodulatory protein FIP-fve from Flammulina velutipes. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2013; 61:12044-12052. [PMID: 24274472 DOI: 10.1021/jf4030272] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
FIP-fve is an immunomodulatory protein isolated from Flammulina velutipes that possesses anti-inflammatory and immunomodulatory activities. However, little is known about its anticancer effects. It is suppressed cell proliferation of A549 lung cancer cells on MTT assay following 48 h treatment of FIP-fve. FIP-fve treatment also resulted in cell cycle arrest but not apoptosis on flow cytometry. This immunomodulatory protein was observed to increase p53 expression, as well as the expression of its downstream gene p21, on Western blot. FIP-fve inhibited migration of A549 cells on wound healing assay and decreased filopodia fiber formation on labeling with Texas Red-X phalloidin. To confirm the effect of FIP-fve on the role of Rac1 in filopodia formation, we investigated the activity of Rac1 in A549 cells following FIP-fve treatment. FIP-fve inhibited EGF-induced activation of Rac1. We demonstrated that FIP-fve decreases RACGAP1 mRNA and protein levels on RT-PCR and Western blot. In addition, the reporter activity of RACGAP1 was reduced by FIP-fve on RacGAP1 promoter assay. Silencing of RacGAP1 decreased cell migration, and overexpression of RacGAP1 increased cell migration in A549 cells. In conclusion, FIP-fve inhibits lung cancer cell migration via RacGAP1 and suppresses the proliferation of A549 via p53 activation pathway.
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Affiliation(s)
- Yu-Chi Chang
- Institute of Medicine, Chung Shan Medical University , No. 110, Sec. 1, Chien-Kuo N. Road, Taichung 40203, Taiwan
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Sánchez-Tilló E, de Barrios O, Siles L, Amendola PG, Darling DS, Cuatrecasas M, Castells A, Postigo A. ZEB1 Promotes invasiveness of colorectal carcinoma cells through the opposing regulation of uPA and PAI-1. Clin Cancer Res 2013; 19:1071-82. [PMID: 23340304 DOI: 10.1158/1078-0432.ccr-12-2675] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE Carcinoma cells enhance their invasive capacity through dedifferentiation and dissolution of intercellular adhesions. A key activator of this process is the ZEB1 transcription factor, which is induced in invading cancer cells by canonical Wnt signaling (β-catenin/TCF4). Tumor invasiveness also entails proteolytic remodeling of the peritumoral stroma. This study aimed to investigate the potential regulation by ZEB1 of the plasminogen proteolytic system constituted by the urokinase plasminogen activator (uPA), and its inhibitor, plasminogen activator inhibitor-1 (PAI-1). EXPERIMENTAL DESIGN Through multiple experimental approaches, colorectal carcinoma (CRC) cell lines and samples from human primary CRC and ZEB1 (-/-) mice were used to examine ZEB1-mediated regulation of uPA and PAI-1 at the protein, mRNA, and transcriptional level. RESULTS ZEB1 regulates uPA and PAI-1 in opposite directions: induces uPA and inhibits PAI-1. In vivo expression of uPA depends on ZEB1 as it is severely reduced in the developing intestine of ZEB1 null (-/-) mice. Optimal induction of uPA by Wnt signaling requires ZEB1 expression. ZEB1 binds to the uPA promoter and activates its transcription through a mechanism implicating the histone acetyltransferase p300. In contrast, inhibition of PAI-1 by ZEB1 does not involve transcriptional repression but rather downregulation of mRNA stability. ZEB1-mediated tumor cell migration and invasion depend on its induction of uPA. ZEB1 coexpresses with uPA in cancer cells at the invasive front of CRCs. CONCLUSIONS ZEB1 promotes tumor invasiveness not only via induction in cancer cells of a motile dedifferentiated phenotype but also by differential regulation of genes involved in stroma remodeling.
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Affiliation(s)
- Ester Sánchez-Tilló
- Group of Transcriptional Regulation of Gene Expression, Department of Oncology and Hematology, IDIBAPS, Barcelona, Spain
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Karandashova S, Florova G, Azghani AO, Komissarov AA, Koenig K, Tucker TA, Allen TC, Stewart K, Tvinnereim A, Idell S. Intrapleural adenoviral delivery of human plasminogen activator inhibitor-1 exacerbates tetracycline-induced pleural injury in rabbits. Am J Respir Cell Mol Biol 2012; 48:44-52. [PMID: 23002099 DOI: 10.1165/rcmb.2012-0183oc] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Elevated concentrations of plasminogen activator inhibitor-1 (PAI-1) are associated with pleural injury, but its effects on pleural organization remain unclear. A method of adenovirus-mediated delivery of genes of interest (expressed under a cytomegalovirus promoter) to rabbit pleura was developed and used with lacZ and human (h) PAI-1. Histology, β-galactosidase staining, Western blotting, enzymatic and immunohistochemical analyses of pleural fluids (PFs), lavages, and pleural mesothelial cells were used to evaluate the efficiency and effects of transduction. Transduction was selective and limited to the pleural mesothelial monolayer. The intrapleural expression of both genes was transient, with their peak expression at 4 to 5 days. On Day 5, hPAI-1 (40-80 and 200-400 nM of active and total hPAI-1 in lavages, respectively) caused no overt pleural injury, effusions, or fibrosis. The adenovirus-mediated delivery of hPAI-1 with subsequent tetracycline-induced pleural injury resulted in a significant exacerbation of the pleural fibrosis observed on Day 5 (P = 0.029 and P = 0.021 versus vehicle and adenoviral control samples, respectively). Intrapleural fibrinolytic therapy (IPFT) with plasminogen activators was effective in both animals overexpressing hPAI-1 and control animals with tetracycline injury alone. An increase in intrapleural active PAI-1 (from 10-15 nM in control animals to 20-40 nM in hPAI-1-overexpressing animals) resulted in the increased formation of PAI-1/plasminogen activator complexes in vivo. The decrease in intrapleural plasminogen-activating activity observed at 10 to 40 minutes after IPFT correlates linearly with the initial concentration of active PAI-1. Therefore, active PAI-1 in PFs affects the outcome of IPFT, and may be both a biomarker of pleural injury and a molecular target for its treatment.
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Affiliation(s)
- Sophia Karandashova
- Texas Lung Injury Institute, University of Texas Health Science Center at Tyler, Tyler, TX 75708, USA
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Tucker TA, Williams L, Koenig K, Kothari H, Komissarov AA, Florova G, Mazar AP, Allen TC, Bdeir K, Mohan Rao LV, Idell S. Lipoprotein receptor-related protein 1 regulates collagen 1 expression, proteolysis, and migration in human pleural mesothelial cells. Am J Respir Cell Mol Biol 2012; 46:196-206. [PMID: 22298529 DOI: 10.1165/rcmb.2011-0071oc] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The low-density lipoprotein receptor-related protein 1 (LRP-1) binds and can internalize a diverse group of ligands, including members of the fibrinolytic pathway, urokinase plasminogen activator (uPA), and its receptor, uPAR. In this study, we characterized the role of LRP-1 in uPAR processing, collagen synthesis, proteolysis, and migration in pleural mesothelial cells (PMCs). When PMCs were treated with the proinflammatory cytokines TNF-α and IL-1β, LRP-1 significantly decreased at the mRNA and protein levels (70 and 90%, respectively; P < 0.05). Consequently, uPA-mediated uPAR internalization was reduced by 80% in the presence of TNF-α or IL-1β (P < 0.05). In parallel studies, LRP-1 neutralization with receptor-associated protein (RAP) significantly reduced uPA-dependent uPAR internalization and increased uPAR stability in PMCs. LRP-1-deficient cells demonstrated increased uPAR t(1/2) versus LRP-1-expressing PMCs. uPA enzymatic activity was also increased in LRP-1-deficient and neutralized cells, and RAP potentiated uPA-dependent migration in PMCs. Collagen expression in PMCs was also induced by uPA, and the effect was potentiated in RAP-treated cells. These studies indicate that TNF-α and IL-1β regulate LRP-1 in PMCs and that LRP-1 thereby contributes to a range of pathophysiologically relevant responses of these cells.
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Affiliation(s)
- Torry A Tucker
- The Texas Lung Injury Institute, The University of Texas Health Science Center at Tyler, 11937 US Highway 271, Biomedical Research Building, Lab C-5, Tyler, TX 75708, USA.
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Wood bark smoke induces lung and pleural plasminogen activator inhibitor 1 and stabilizes its mRNA in porcine lung cells. Shock 2012; 36:128-37. [PMID: 21478814 DOI: 10.1097/shk.0b013e31821d60a4] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Although aberrant fibrinolysis and plasminogen activator inhibitor 1 (PAI-1) are implicated in acute lung injury, the role of this serpin in the pathogenesis of wood bark smoke (WBS)-induced acute lung injury (SIALI) and its regulation in resident lung cells after exposure to smoke are unclear. A total of 22 mechanically ventilated pigs were included in this study. Immunohistochemical analyses were used to assess fibrin and PAI-1 in the lungs of pigs with SIALI in situ. Plasminogen activator inhibitor 1 was measured in bronchoalveolar lavage fluids by Western blotting. Induction of PAI-1 was determined at the protein and mRNA levels by Western and polymerase chain reaction analyses in primary porcine alveolar type II cells, fibroblasts, and pleural mesothelial cells. Plasminogen activator inhibitor 1 mRNA stability was determined by transcription chase studies. Gel shift analyses were used to characterize the mechanism regulating PAI-1 mRNA stability. Smoke-induced ALI induced PAI-1, with prominent extravascular fibrin deposition in large and small airways as well as alveolar and subpleural compartments. In pleural mesothelial cells, lung fibroblasts, and alveolar type II cells, PAI-1 mRNA was stabilized by WBS extract and contributed to induction of PAI-1. The mechanism involves dissociation of a novel 6-phospho-d-gluconate-NADP oxidoreductase-like PAI-1 mRNA binding protein from PAI-1 mRNA. Exposure to WBS induces prominent airway and mesothelial expression of PAI-1, associated with florid distribution of fibrin in SIALI in vivo Wood bark smoke components induce PAI-1 in vitro in part by stabilization of PAI-1 mRNA, a newly recognized pathway that may promote extravascular fibrin deposition and lung dysfunction in SIALI.
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Shetty SK, Marudamuthu AS, Abernathy D, Shetty RS, Shetty P, Fu J, Idell S, Bhandary YP, Ji H, Liu MC, Shetty S. Regulation of urokinase expression at the posttranscription level by lung epithelial cells. Biochemistry 2011; 51:205-13. [PMID: 22166006 DOI: 10.1021/bi201293x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Urokinase-type plasminogen activator (uPA) is expressed by lung epithelial cells and regulates fibrin turnover and epithelial cell viability. PMA, LPS, and TNF-alpha, as well as uPA itself, induce uPA expression in lung epithelial cells. PMA, LPS, and TNF-alpha induce uPA expression through increased synthesis as well as stabilization of uPA mRNA, while uPA increases its own expression solely through uPA mRNA stabilization. The mechanism by which lung epithelial cells regulate uPA expression at the level of mRNA stability is unclear. To elucidate this process, we sought to characterize protein-uPA mRNA interactions that regulate uPA expression. Regulation of uPA at the level of mRNA stability involves the interaction of a ~40 kDa cytoplasmic-nuclear shuttling protein with a 66 nt uPA mRNA 3'UTR sequence. We purified the uPA mRNA 3'UTR binding protein and identified it as ribonucleotide reductase M2 (RRM2). We expressed recombinant RRM2 and confirmed its interaction with a specific 66 nt uPA 3'UTR sequence. Immunoprecipitation of cell lysates with anti-RRM2 antibody and RT-PCR for uPA mRNA confirmed that RRM2 binds to uPA mRNA. Treatment of Beas2B cells with uPA or LPS attenuated RRM2-endogenous uPA mRNA interactions, while overexpression of RRM2 inhibited uPA protein and mRNA expression through destabilization of uPA mRNA. LPS exposure of lung epithelial cells translocates RRM2 from the cytoplasm to the nucleus in a time-dependent manner, leading to stabilization of uPA mRNA. This newly recognized pathway could influence uPA expression and a broad range of uPA-dependent functions in lung epithelial cells in the context of lung inflammation and repair.
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Affiliation(s)
- Shwetha K Shetty
- Texas Lung Injury Institute, The University of Texas Health Science Center, Tyler, Texas 75708, United States
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Asakura T, Iwaki S, Okada H, Sobel BE, Fujii S. Posttranscriptional regulation of expression of plasminogen activator inhibitor type-1 by cAMP in HepG2 liver cells. J Biochem 2011; 150:687-94. [PMID: 21878476 DOI: 10.1093/jb/mvr110] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Altered expression of plasminogen activator inhibitor type-1 (PAI-1), a physiologic fibrinolysis inhibitor, is implicated in atherosclerosis. Cyclic adenosine monophosphate (cAMP) alters PAI-1 expression in several cells. Nevertheless, posttranscriptional regulation of PAI-1 has not been elucidated. To determine whether cAMP affects PAI-1 expression at posttranscriptional level, we determined promoter activity, mRNA levels, 3'-untranslated region (UTR) activity and protein levels of PAI-1 using HepG2 cells. cAMP decreased PAI-1 promoter activity at 24 h and mRNA expression at 4 h while it increased mRNA expression and accumulation of PAI-1 protein into media at 24 h. Human PAI-1 mRNA exists in two subspecies (3.2 and 2.2 kb), and cAMP increased baseline luciferase activity of 3'-UTR of the 3.2 kb PAI-1 mRNA [3'-UTR (+1358-3176)] and 1 kb fragment of 3'-terminus of 3'-UTR of 3.2 kb mRNA [3'-UTR (+2177-3176)]. cAMP increased PAI-1 protein expression despite decrease in promoter activity, presumably by regulating PAI-1 expression at the posttranscriptional level and thereby affecting mRNA stability. The 53-nt fragment in 3'-UTR (+2591 to +2643 nt) was involved in posttranscriptional regulation by cAMP. Thus, cAMP can stabilize 3.2 kb PAI-1 mRNA mediated by specific effects on 3'-UTR, and these effects are associated with increased expression of PAI-1 protein.
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Affiliation(s)
- Takefumi Asakura
- Department of Molecular and Cellular Pathobiology and Therapeutics, Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya, Japan
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Sidi R, Pasello G, Opitz I, Soltermann A, Tutic M, Rehrauer H, Weder W, Stahel RA, Felley-Bosco E. Induction of senescence markers after neo-adjuvant chemotherapy of malignant pleural mesothelioma and association with clinical outcome: an exploratory analysis. Eur J Cancer 2010; 47:326-32. [PMID: 21036600 DOI: 10.1016/j.ejca.2010.09.044] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2010] [Accepted: 09/28/2010] [Indexed: 10/18/2022]
Abstract
The aim of this study was to assess the induction of senescence markers versus apoptosis pathways in malignant pleural mesothelioma (MPM) tumour samples before and after neo-adjuvant platinum-based chemotherapy and to investigate their relationship with clinical outcome. Specific senescence pathways were assessed by quantifying the expression of p21 and plasminogen activator inhibitor-1 (PAI-1) for the p21-p53 pathway, IGFBP7 for the IGF pathway and ALDH1A3 for the IFN pathway. p21 and PAI-1 expression were also assessed by immunohistochemistry. In addition, beta-galactosidase activity staining at pH 6.0 was performed. Apoptosis was determined by TUNEL assay. Clinical outcome was assessed by modified RECIST criteria, progression-free and overall survival. In a training set (n=9 patients) paired comparison demonstrated a significant increase in p21 (p<0.05), PAI-1 (p<0.01) and apoptosis (p<0.01) after neo-adjuvant chemotherapy. The patients with the highest increase in PAI-1 had stable disease, whilst patients with little change in senescence markers accompanied by a high increase in apoptosis had an objective response after chemotherapy. The hypothesis that stable disease might be associated with an increase in senescence markers was confirmed in a tissue microarray (n=26 patients) using p21 and PAI-1 immunohistochemistry as readouts. For patients where survival and time to progression data were available, increased PAI-1 levels were significantly associated with a worst outcome. Our results demonstrate induction of senescence markers by neo-adjuvant chemotherapy in a proportion of patients with MPM and its potential association with a poor outcome.
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Affiliation(s)
- Roy Sidi
- Laboratory of Molecular Oncology, Clinic and Policlinic of Oncology, University Hospital of Zürich, Häldeliweg 4, 8044 Zürich, Switzerland
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