The Experts below are selected from a list of 1863 Experts worldwide ranked by ideXlab platform
Jean-françois Beaulieu - One of the best experts on this subject based on the ideXlab platform.
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A Stool Multitarget mRNA Assay for the Detection of Colorectal Neoplasms.
Methods of Molecular Biology, 2018Co-Authors: Elizabeth Herring, Shigeru Kanaoka, Eric Tremblay, Jean-françois BeaulieuAbstract:Noninvasive screening methods for the detection of colorectal cancers (CRC) at curable stages rely on the identification of specific biomarkers. Our group has shown that mRNA stool assays represent a powerful and robust approach for the prediction of colorectal neoplasms. In this methodological chapter, we describe the procedures to isolate good quality stool RNA and the steps to evaluate the levels of specific host mRNA markers such as ITGA6, MYC, and GADD45B using TaqMan-based quantitative and droplet digital PCR approaches.
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MYC Regulates α6 Integrin Subunit Expression and Splicing Under Its Pro-Proliferative ITGA6A Form in Colorectal Cancer Cells.
Cancers, 2018Co-Authors: Jean-françois Groulx, Salah Boudjadi, Jean-françois BeaulieuAbstract:The α6 integrin subunit (ITGA6) pre-mRNA undergoes alternative splicing to form two splicing variants, named ITGA6A and ITGA6B. In primary human colorectal cancer cells, the levels of both ITGA6 and β4 integrin subunit (ITGB4) subunits of the α6β4 integrin are increased. We previously found that the upregulation of ITGA6 is a direct consequence of the increase of the pro-proliferative ITGA6A variant. However, the mechanisms that control ITGA6 expression and splicing into the ITGA6A variant over ITGA6B in colorectal cancer cells remain poorly understood. Here, we show that the promoter activity of the ITGA6 gene is regulated by MYC. Pharmacological inhibition of MYC activity with the MYC inhibitor (MYCi) 10058-F4 or knockdown of MYC expression by short hairpin RNA (shRNA) both lead to a decrease in ITGA6 and ITGA6A levels in colorectal cancer cells, while overexpression of MYC enhances ITGA6 promoter activity. We also found that MYC inhibition decreases the epithelial splicing regulatory protein 2 (ESRP2) splicing factor at both the mRNA and protein levels. Chromatin immunoprecipitation revealed that the proximal promoter sequences of ITGA6 and ESRP2 were occupied by MYC and actively transcribed in colorectal cancer cells. Furthermore, expression studies in primary colorectal tumors and corresponding resection margins confirmed that the up-regulation of the ITGA6A subunit can be correlated with the increase in MYC and ESRP2. Taken together, our results demonstrate that the proto-oncogene MYC can regulate the promoter activation and splicing of the ITGA6 integrin gene through ESRP2 to favor the production of the pro-proliferative ITGA6A variant in colorectal cancer cells.
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droplet digital pcr for quantification of ITGA6 in a stool mrna assay for the detection of colorectal cancers
World Journal of Gastroenterology, 2017Co-Authors: Elizabeth Herring, Shigeru Kanaoka, Eric Tremblay, Jean-françois BeaulieuAbstract:Droplet digital PCR for quantification of ITGA6 in a stool mRNA assay for the detection of colorectal cancers
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Use of integrin alpha 6 transcripts in a stool mRNA assay for the detection of colorectal cancers at curable stages
Oncotarget, 2016Co-Authors: Jean-françois Beaulieu, Elizabeth Herring, Shigeru Kanaoka, Eric TremblayAbstract:// Jean-Francois Beaulieu 1 , Elizabeth Herring 1 , Shigeru Kanaoka 2 , Eric Tremblay 1 1 Laboratory of Intestinal Physiopathology, Faculty of Medicine and Health Sciences, Universite de Sherbrooke, Sherbrooke, QC, Canada 2 Department of Gastroenterology, Hamamatsu Medical Center, Hamamatsu, Japan Correspondence to: Jean-Francois Beaulieu, e-mail: Jean-Francois.Beaulieu@USherbrooke.ca Keywords: colorectal cancer, adenomas, non-invasive screening, biomarker, mRNA Received: December 17, 2015 Accepted: January 30, 2016 Published: February 15, 2016 ABSTRACT Objective: An important criterion for colorectal cancer (CRC) screening is the ability to detect lesions at a curable stage. In the present study, we have assessed the integrin α6 subunit transcript ( ITGA6 ) as part of a stool assay for the detection of colorectal lesions. Results: In comparison with control samples, ITGA6 levels were found to be significantly increased at all stages ( P < 0.01). Receiver operating characteristic analysis revealed areas under the curve of 0.89 for the prediction of CRC with 81% sensitivity and 88% specificity and of 0.90 for the prediction of advanced adenomas (Ad) with 75% sensitivity and 88% specificity. The ITGA6A variant was also found to be increased relative to ITGA6 in stage II and III CRCs. Combining ITGA6 with other selected transcripts and/or immunochemical fecal occult blood test (iFOBT) results further increased sensitivity and specificity for the detection of colorectal lesions. Patients and Methods: ITGA6 detection used alone and under various combinations including detection of other mRNA markers and iFOBT was assessed on stool samples obtained from 175 patients (91 CRCs, 24 Ad and 60 healthy controls). Conclusions: These data confirm the usefulness and reliability of an mRNA stool assay for the detection of colorectal lesions. The validation of additional candidate genes and their analysis in multiplex qPCR represents a powerful and robust approach that can be combined with iFOBT results to improve the detection of colorectal lesions.
Elizabeth Herring - One of the best experts on this subject based on the ideXlab platform.
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A Stool Multitarget mRNA Assay for the Detection of Colorectal Neoplasms.
Methods of Molecular Biology, 2018Co-Authors: Elizabeth Herring, Shigeru Kanaoka, Eric Tremblay, Jean-françois BeaulieuAbstract:Noninvasive screening methods for the detection of colorectal cancers (CRC) at curable stages rely on the identification of specific biomarkers. Our group has shown that mRNA stool assays represent a powerful and robust approach for the prediction of colorectal neoplasms. In this methodological chapter, we describe the procedures to isolate good quality stool RNA and the steps to evaluate the levels of specific host mRNA markers such as ITGA6, MYC, and GADD45B using TaqMan-based quantitative and droplet digital PCR approaches.
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droplet digital pcr for quantification of ITGA6 in a stool mrna assay for the detection of colorectal cancers
World Journal of Gastroenterology, 2017Co-Authors: Elizabeth Herring, Shigeru Kanaoka, Eric Tremblay, Jean-françois BeaulieuAbstract:Droplet digital PCR for quantification of ITGA6 in a stool mRNA assay for the detection of colorectal cancers
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Use of integrin alpha 6 transcripts in a stool mRNA assay for the detection of colorectal cancers at curable stages
Oncotarget, 2016Co-Authors: Jean-françois Beaulieu, Elizabeth Herring, Shigeru Kanaoka, Eric TremblayAbstract:// Jean-Francois Beaulieu 1 , Elizabeth Herring 1 , Shigeru Kanaoka 2 , Eric Tremblay 1 1 Laboratory of Intestinal Physiopathology, Faculty of Medicine and Health Sciences, Universite de Sherbrooke, Sherbrooke, QC, Canada 2 Department of Gastroenterology, Hamamatsu Medical Center, Hamamatsu, Japan Correspondence to: Jean-Francois Beaulieu, e-mail: Jean-Francois.Beaulieu@USherbrooke.ca Keywords: colorectal cancer, adenomas, non-invasive screening, biomarker, mRNA Received: December 17, 2015 Accepted: January 30, 2016 Published: February 15, 2016 ABSTRACT Objective: An important criterion for colorectal cancer (CRC) screening is the ability to detect lesions at a curable stage. In the present study, we have assessed the integrin α6 subunit transcript ( ITGA6 ) as part of a stool assay for the detection of colorectal lesions. Results: In comparison with control samples, ITGA6 levels were found to be significantly increased at all stages ( P < 0.01). Receiver operating characteristic analysis revealed areas under the curve of 0.89 for the prediction of CRC with 81% sensitivity and 88% specificity and of 0.90 for the prediction of advanced adenomas (Ad) with 75% sensitivity and 88% specificity. The ITGA6A variant was also found to be increased relative to ITGA6 in stage II and III CRCs. Combining ITGA6 with other selected transcripts and/or immunochemical fecal occult blood test (iFOBT) results further increased sensitivity and specificity for the detection of colorectal lesions. Patients and Methods: ITGA6 detection used alone and under various combinations including detection of other mRNA markers and iFOBT was assessed on stool samples obtained from 175 patients (91 CRCs, 24 Ad and 60 healthy controls). Conclusions: These data confirm the usefulness and reliability of an mRNA stool assay for the detection of colorectal lesions. The validation of additional candidate genes and their analysis in multiplex qPCR represents a powerful and robust approach that can be combined with iFOBT results to improve the detection of colorectal lesions.
Wilson Savino - One of the best experts on this subject based on the ideXlab platform.
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ITGA6 gene silencing by RNA interference modulates the expression of a large number of cell migration-related genes in human thymic epithelial cells
BMC Genomics, 2013Co-Authors: Daiane Cristina Ferreira Golbert, Eliane Correa-de-santana, Marcelo Ribeiro-alves, Ana Tereza Ribeiro De Vasconcelos, Wilson SavinoAbstract:Background The thymic epithelium is the major microenvironmental component of the thymus, the primary lymphoid organ responsible for the generation of T lymphocytes. Thymic epithelial cells (TEC) control intrathymic T cell differentiation by means of distinct types of interactions. TEC constitutively produce chemokines and extracellular matrix ligands (such as laminin and fibronectin) and express corresponding receptors, which allow thymocytes to migrate in a very ordered fashion. We previously showed that laminin mediates TEC/thymocyte interactions in both mice and humans. More recently, we used RNAi technology to knock-down the ITGA5 gene (which encodes CD49e, the integrin α-chain subunit of the fibronectin receptor VLA-5) in cultured human TEC. Using a similar strategy, herein we knocked-down the ITGA6 gene, which encodes CD49f, the α-chain of two integrin-type laminin receptors, namely VLA-6 (α6β1) and α6β4. Results We first confirmed that RNAi-induced knock-down of the ITGA6 gene was successful, at both transcription and translational levels, with a significant decrease in the membrane expression of CD49f, apart from CD49b, CD49c and CD49d, ascertained by cytofluorometry on living TEC. We also demonstrated that such knock-down promotes a decrease in cell adhesion to laminin. Using quantitative PCR, we demonstrated that gene expression of other integrin α-chains were concomitantly down-regulated, particularly those which form other laminin receptors, including ITGA1, ITGA2 and ITGA7. Interestingly enough, LAMA1 gene expression (whose corresponding protein chain is part of laminin-111) was largely increased in ITGA6 knocked-down TEC cultures. Lastly, the network complexity of gene expression under ITGA6 influence is much broader, since we found that other cell migration-related genes, namely those coding for various chemokines, are also modulated when IGTA6 is knocked-down. Conclusion The data presented herein clearly show that down regulation of ITGA6 gene in the human thymic epithelium triggers a complex cascade of effects upon the expression levels of several other cell migration-related genes, including extracellular matrix and chemokine ligands and receptors. Taken together, these data unravel the concept that the expression of genes involved in controlling of thymocyte migration by the thymic microenvironment should be regarded as complex networks, so that a defect in the expression of one single gene may reflect in an amplified cascade with functional consequences for TEC adhesion onto the natural ligand and potential consequences upon the normal patterns of TEC/thymocyte interactions.
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ITGA6 gene silencing by rna interference modulates the expression of a large number of cell migration related genes in human thymic epithelial cells
BMC Genomics, 2013Co-Authors: Daiane Cristina Ferreira Golbert, Ana Tereza Ribeiro De Vasconcelos, Eliane Correadesantana, Marcelo Ribeiroalves, Wilson SavinoAbstract:The thymic epithelium is the major microenvironmental component of the thymus, the primary lymphoid organ responsible for the generation of T lymphocytes. Thymic epithelial cells (TEC) control intrathymic T cell differentiation by means of distinct types of interactions. TEC constitutively produce chemokines and extracellular matrix ligands (such as laminin and fibronectin) and express corresponding receptors, which allow thymocytes to migrate in a very ordered fashion. We previously showed that laminin mediates TEC/thymocyte interactions in both mice and humans. More recently, we used RNAi technology to knock-down the ITGA5 gene (which encodes CD49e, the integrin α-chain subunit of the fibronectin receptor VLA-5) in cultured human TEC. Using a similar strategy, herein we knocked-down the ITGA6 gene, which encodes CD49f, the α-chain of two integrin-type laminin receptors, namely VLA-6 (α6β1) and α6β4. We first confirmed that RNAi-induced knock-down of the ITGA6 gene was successful, at both transcription and translational levels, with a significant decrease in the membrane expression of CD49f, apart from CD49b, CD49c and CD49d, ascertained by cytofluorometry on living TEC. We also demonstrated that such knock-down promotes a decrease in cell adhesion to laminin. Using quantitative PCR, we demonstrated that gene expression of other integrin α-chains were concomitantly down-regulated, particularly those which form other laminin receptors, including ITGA1, ITGA2 and ITGA7. Interestingly enough, LAMA1 gene expression (whose corresponding protein chain is part of laminin-111) was largely increased in ITGA6 knocked-down TEC cultures. Lastly, the network complexity of gene expression under ITGA6 influence is much broader, since we found that other cell migration-related genes, namely those coding for various chemokines, are also modulated when IGTA6 is knocked-down. The data presented herein clearly show that down regulation of ITGA6 gene in the human thymic epithelium triggers a complex cascade of effects upon the expression levels of several other cell migration-related genes, including extracellular matrix and chemokine ligands and receptors. Taken together, these data unravel the concept that the expression of genes involved in controlling of thymocyte migration by the thymic microenvironment should be regarded as complex networks, so that a defect in the expression of one single gene may reflect in an amplified cascade with functional consequences for TEC adhesion onto the natural ligand and potential consequences upon the normal patterns of TEC/thymocyte interactions.
Ming Xu - One of the best experts on this subject based on the ideXlab platform.
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retracted twist2 promotes kidney cancer cell proliferation and invasion via regulating ITGA6 and cd44 expression in the ecm receptor interaction pathway
Biomedicine & Pharmacotherapy, 2016Co-Authors: Haojie Zhang, Lu Sheng, Xin Hu, Ruiming Rong, Ming XuAbstract:: Twist2 is a member of the basic helix-loop-helix (bHLH) family and plays a critical role in tumorigenesis. Growing evidence proves that Twist2 involves in tumor progression; however, the role of Twist2 in human kidney cancer and its underlying mechanisms remain unclear. RT-PCR and Western blot analysis were used to detect the expression of Twist2 in kidney cancer cells and tissues. Cell proliferation, cell cycle, apoptosis, migration and invasion assay was measured by the Cell Count Kit-8 (CCK8), flow cytometry, wound healing and transwell analysis, respectively. Gene set enrichment analysis (GSEA) was used to identify correlation of Twist2 with ECM-Receptor-Interaction pathway. In this report, we show that Twist2 up-regulated in human kidney cancer tissues compared with normal kidney tissues. Twist2 promotes cell proliferation, inhibits cell apoptosis, augments cell migration and invasion in human kidney cancer-derived cell in vitro, and promotes tumor growth in vivo. Moreover, we found that knockdown of Twist2 decreased the levels of ITGA6 and CD44 which contribute to cell migration and invasion correlated with ECM-Receptor-Interaction pathway. This result indicates Twist2 may promote migration and invasion of kidney cancer cells by regulating ITGA6 and CD44 expression. Therefore, our data demonstrated that Twist2 involves in kidney cancer progression. The identification of the role Twist2 on the migration and invasion of kidney cancer provides a potential appropriate treatment after radical nephrectomy to get a better prognosis that reducing recurrence.
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twist2 promotes kidney cancer cell proliferation and invasion by regulating ITGA6 and cd44 expression in the ecm receptor interaction pathway
OncoTargets and Therapy, 2016Co-Authors: Haojie Zhang, Lu Sheng, Xin Hu, Ruiming Rong, Ming XuAbstract:Twist2 is a member of the basic helix-loop-helix (bHLH) family and plays a critical role in tumorigenesis. Growing evidence has proven that Twist2 is involved in tumor progression; however, the role of Twist2 in human kidney cancer and its underlying mechanisms remain unclear. Real-time polymerase chain reaction and Western blot analysis were used to detect the expression of Twist2 in kidney cancer cells and tissues. Cell proliferation, cell cycle, apoptosis, migration, and invasion assay were analyzed using the Cell Count Kit-8, flow cytometry, wound healing, and Transwell analysis, respectively. In this study, we showed that Twist2 was upregulated in human kidney cancer tissues compared with normal kidney tissues. Twist2 promoted cell proliferation, inhibited cell apoptosis, and augmented cell migration and invasion in human kidney-cancer-derived cells in vitro. Twist2 also promoted tumor growth in vivo. Moreover, we found that the knockdown of Twist2 decreased the levels of ITGA6 and CD44 expression. This result indicates that Twist2 may promote migration and invasion of kidney cancer cells by regulating ITGA6 and CD44 expression. Therefore, our data demonstrated that Twist2 is involved in kidney cancer progression. The identification of the role of Twist2 in the migration and invasion of kidney cancer provides a potential appropriate treatment for human kidney cancer.
Eric Tremblay - One of the best experts on this subject based on the ideXlab platform.
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A Stool Multitarget mRNA Assay for the Detection of Colorectal Neoplasms.
Methods of Molecular Biology, 2018Co-Authors: Elizabeth Herring, Shigeru Kanaoka, Eric Tremblay, Jean-françois BeaulieuAbstract:Noninvasive screening methods for the detection of colorectal cancers (CRC) at curable stages rely on the identification of specific biomarkers. Our group has shown that mRNA stool assays represent a powerful and robust approach for the prediction of colorectal neoplasms. In this methodological chapter, we describe the procedures to isolate good quality stool RNA and the steps to evaluate the levels of specific host mRNA markers such as ITGA6, MYC, and GADD45B using TaqMan-based quantitative and droplet digital PCR approaches.
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droplet digital pcr for quantification of ITGA6 in a stool mrna assay for the detection of colorectal cancers
World Journal of Gastroenterology, 2017Co-Authors: Elizabeth Herring, Shigeru Kanaoka, Eric Tremblay, Jean-françois BeaulieuAbstract:Droplet digital PCR for quantification of ITGA6 in a stool mRNA assay for the detection of colorectal cancers
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Use of integrin alpha 6 transcripts in a stool mRNA assay for the detection of colorectal cancers at curable stages
Oncotarget, 2016Co-Authors: Jean-françois Beaulieu, Elizabeth Herring, Shigeru Kanaoka, Eric TremblayAbstract:// Jean-Francois Beaulieu 1 , Elizabeth Herring 1 , Shigeru Kanaoka 2 , Eric Tremblay 1 1 Laboratory of Intestinal Physiopathology, Faculty of Medicine and Health Sciences, Universite de Sherbrooke, Sherbrooke, QC, Canada 2 Department of Gastroenterology, Hamamatsu Medical Center, Hamamatsu, Japan Correspondence to: Jean-Francois Beaulieu, e-mail: Jean-Francois.Beaulieu@USherbrooke.ca Keywords: colorectal cancer, adenomas, non-invasive screening, biomarker, mRNA Received: December 17, 2015 Accepted: January 30, 2016 Published: February 15, 2016 ABSTRACT Objective: An important criterion for colorectal cancer (CRC) screening is the ability to detect lesions at a curable stage. In the present study, we have assessed the integrin α6 subunit transcript ( ITGA6 ) as part of a stool assay for the detection of colorectal lesions. Results: In comparison with control samples, ITGA6 levels were found to be significantly increased at all stages ( P < 0.01). Receiver operating characteristic analysis revealed areas under the curve of 0.89 for the prediction of CRC with 81% sensitivity and 88% specificity and of 0.90 for the prediction of advanced adenomas (Ad) with 75% sensitivity and 88% specificity. The ITGA6A variant was also found to be increased relative to ITGA6 in stage II and III CRCs. Combining ITGA6 with other selected transcripts and/or immunochemical fecal occult blood test (iFOBT) results further increased sensitivity and specificity for the detection of colorectal lesions. Patients and Methods: ITGA6 detection used alone and under various combinations including detection of other mRNA markers and iFOBT was assessed on stool samples obtained from 175 patients (91 CRCs, 24 Ad and 60 healthy controls). Conclusions: These data confirm the usefulness and reliability of an mRNA stool assay for the detection of colorectal lesions. The validation of additional candidate genes and their analysis in multiplex qPCR represents a powerful and robust approach that can be combined with iFOBT results to improve the detection of colorectal lesions.
