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Nicole Porchet - One of the best experts on this subject based on the ideXlab platform.
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Detection of bone marrow-disseminated breast cancer cells using an RT-PCR assay of MUC5B mRNA.
International journal of cancer, 2002Co-Authors: Nora Berois, Nicole Porchet, Cecilia Sóñora, Mario Varangot, Leticia Zarantonelli, Carlos Pressa, Raúl Laviña, José Luis Rodríguez, Fernando Delgado, Jean-pierre AubertAbstract:The evaluation of disseminated epithelial tumor cells in breast cancer patients has generated considerable interest due to its potential association with disease recurrence. Our work was performed to analyze the usefulness of 5 mucin genes expression (MUC2, MUC3, MUC5B, MUC6 and MUC7), using RT-PCR assays, to detect disseminated cancer cells in patients with operable breast cancer. The highest frequencies of positive RT-PCR tests in breast tumor extracts were observed for MUC5B (7/15) and MUC7 (5/12). The best specificity, negative results on all peripheral blood mononuclear (PBMN) cell samples from healthy donors, were shown for MUC2, MUC5B and MUC6 RT-PCR assays. Thus, we selected MUC5B as a target gene for further evaluation. Using a nested RT-PCR, MUC5B mRNA transcripts were detected in 16/31 primary breast tumors (but not in 36 samples of normal PBMN cells) and in the human MCF-7 breast cancer cell line but not in BT20, MDA, T47D and ZR-75 breast cancer cell lines, indicating that MUC5B mRNA is expressed in a population of breast cancer cells. Using this method, 9/46 patients (19.5%) who underwent curative surgery showed positive MUC5B mRNA in bone marrow aspirates obtained prior to surgery, including 5/24 patients (20.8%) with stage I or II breast cancer, without histopathologic lymph node involvement. These results indicate that MUC5B mRNA could be a specific marker applicable to the molecular diagnosis of breast cancer cell dissemination. A comparative evaluation between MUC5B mRNA, cytokeratin 19 (CK19) mRNA and carcinoembryonic antigen (CEA) mRNA in all bone marrow aspirates suggests a putative complementation for molecular detection of disseminated carcinoma cells. Considering that breast cancer is characterized by a great phenotypic heterogeneity, the use of multimarker approach could contribute to tumor cell detection in bone marrow and blood. © 2002 Wiley-Liss, Inc.
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Mucin gene expression in intraductal papillary-mucinous pancreatic tumours and related lesions.
The Journal of pathology, 2002Co-Authors: Benoit Terris, Nicole Porchet, Marie-pierre Buisine, Jean-pierre Aubert, Sylvie Dubois, Alain Sauvanet, Philippe Ruszniewski, Anne Couvelard, Claude Degott, Jean-françois FléjouAbstract:Intraductal papillary-mucinous tumours (IPMTs) of the pancreas are heterogeneous proliferations characterized by a malignant potential. The molecular mechanisms underlying the tumourigenesis process are not well understood. Recently, it has been shown that IPMTs secreting the mucin antigen MUC2 have a better prognosis, but the complete pattern of MUC gene expression has not yet been established. The aims of this study were to evaluate the mucin gene expression in 57 IPMTs and eight related lesions surgically resected and to relate MUC gene expression to the histological diagnosis. In situ hybridization (ISH) was performed in 28 cases with probes specific for the MUC1, MUC2, MUC3, MUC4, MUC5AC, MUC5B, MUC6, and MUC7 genes. An immunohistochemical analysis was carried in all 65 cases and in 90 conventional ductal adenocarcinomas of the pancreas using MUC1, MUC2, and MUC5AC antibodies. IPMTs of adenoma (dysplasia) type exhibited high expression of MUC2 (93%), MUC5AC (97%), and, to a lesser extent, of MUC4 (71%), all of which were also observed in colloid carcinomas associated with IPMTs. In contrast, IPMTs with simple hyperplasia, intraductal oncocytic papillary neoplasms, and pyloric glandular adenomas exhibited little or no expression of MUC2. The mucin expression profile supports the existence of two types of invasive tumour associated with IPMTs: a colloid and an ordinary form. The latter shows a pattern similar to the conventional ductal adenocarcinomas with a loss of MUC2 and a gain of MUC1 and has a greater tendency to metastasize. In conclusion, the altered expression of mucin, characteristic of IPMT of adenoma type and of colloid carcinomas, may contribute to the better clinical outcome of these neoplasms, compared to conventional pancreatic ductal adenocarcinomas.
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normal respiratory mucosa precursor lesions and lung carcinomas differential expression of human mucin genes
Frontiers in Bioscience, 2001Co-Authors: Mariechristine Copin, Marie-pierre Buisine, L Devisme, Xavier Leroy, Fabienne Escande, B Gosselin, J P Aubert, Nicole PorchetAbstract:Mucins are glycoproteins synthesized by epithelial cells and thought to promote tumor-cell invasion. Eight human mucin genes have been well characterized: MUC2, MUC5AC, MUC5B, MUC6 map to 11p15.5 and encode secretory gel forming mucins while MUC1, MUC3, MUC4, MUC7 are scattered on different chromosomes and encode membrane-bound or secreted mucins. The expression pattern of the mucin genes is complex in normal airways involving six genes, mainly MUC5AC and MUC5B in mucus-producing cells and MUC4 in a wide array of epithelial cells. MUC5AC overexpression in metaplasia, dysplasia and normal epithelium adjacent to squamous cell carcinoma provides additional arguments for a mucous cell origin of preneoplastic squamous lesions. MUC5AC and MUC5B expression is related to mucus formation in adenocarcinomas. Mucinous bronchioloalveolar carcinoma (BAC) has a particular pattern of mucin gene expression indicating that it has sustained a well-differentiated phenotype similar to the goblet cell, correlated with distinctive features i.e. a noninvasive pattern and a better prognosis than nonBACs. MUC4 is the earlier mucin gene expressed in the foregut, before epithelial differentiation and is expressed independently of mucus secretion both in normal adult airways and carcinomas. These findings are in favor the histogenetic theory of non-small-cell carcinoma originating from a pluripotent mucous cell.
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Aberrant Expression of Human Mucin Gene MUC5B in Gastric Carcinoma and Cancer Cells
Journal of Biological Chemistry, 2001Co-Authors: Michael Perrais, Nicole Porchet, Pascal Pigny, Marie-pierre Buisine, Jean-pierre Aubert, Isabelle Van Seuningen-lempireAbstract:In gastric cancer, altered expression of MUC1, MUC2, MUC5AC, and MUC6 mucin genes has already been described. We show in this report by the means of in situ hybridization, reverse transcriptase-polymerase chain reaction, and transfection assays that MUC5B is also abnormally expressed in gastric carcinomatous tissues and cell lines. We thus undertook to elucidate the molecular mechanisms that regulate the transcription of MUC5B in gastric cancer cells. To this end, high expressing (KATO-III) and low expressing (AGS) gastric cancer cell lines were chosen to study human mucin gene MUC5B expression and promoter activity. Sequencing of the promoter region revealed a distal TATA box located 1 kilobase upstream of the proximal TATA box. Functional activity of the promoter was addressed by using deletion mutants covering 2044 nucleotides upstream of the MUC5B transcription start site. We identified a distal promoter 10 times more active than the proximal promoter in KATO-III cells. In AGS cells, both promoters, much less active, showed the same range of activity. Binding assays allowed us to show that the transcription factor ATF-1 binds to a cis-element present in the distal promoter. Sp1, which binds to both promoters specifically transactivates the proximal promoter. Treatment of transfected cells with PMA, cholera toxin A subunit, and calcium ionophore A23187 showed that only PMA led to a substantial activation of the distal promoter. MUC5B 5-flanking region having a high GC content, influence of methylation on the MUC5B expression was assessed. Our results indicate that repression of MUC5B expression visualized in AGS cells is due in part to the presence of numerous methy-lated cytosine residues throughout the 5-flanking region. Altogether these results demonstrate that MUC5B expression in gastric cancer cells is governed by a highly active distal promoter that is up-regulated by protein kinase C and that repression is under the influence of methylation. Mucins are high molecular weight O-glycoproteins synthesized by epithelial cells as large secreted or membrane-bound glycoproteins (1). So far, eight mucin genes have been well characterized (MUC1, MUC2, MUC3, MUC4, MUC5AC, MUC5B, MUC6, and MUC7) (1), and cDNAs have been proposed for MUC8, MUC9, MUC11, and MUC12 (1, 2). Numerous studies have now demonstrated that the expression of mucin genes is tissue-and cell-specific and that their expression is altered during the pathogenesis of several diseases, which suggests that human mucin gene expression is tightly regulated and that they may play important roles during cell differentiation and carcinogenesis (3-8). In normal stomach, MUC5AC is expressed at the surface/ foveolar epithelium and MUC6 in the mucous neck cells and in the antral glands (9-11). Other mucin genes expressed in normal gastric mucosae are MUC1 and to a lesser extent MUC2, MUC3, and MUC4. In gastric carcinomas, a decrease of MUC1, MUC5AC and MUC6 expression and an increase of MUC2, MUC3, and MUC4 expression has already been demonstrated (11-15). Human mucin gene MUC5B has been extensively studied in our laboratory. Studies of MUC5B genomic sequence (39.1 kb) 1 showed that it encodes a high molecular weight polypeptide (627,000) (16-20). MUC5B mucin gene is localized on chromosome 11 (band p15) and is clustered with three other mucin genes: MUC2, MUC6, and MUC5AC (21). In normal adult, MUC5B is essentially expressed in trachea, bronchi, submax-illary glands, pancreas, gallbladder, and endocervix (4, 22-24). In cancer, MUC5B has been shown to be highly expressed in colon carcinoma (5), in HT-29 treated with methotrexate (19, 20, 25), and LS174T (20, 24, 26) mucus-secreting colon cancer cell lines. We recently characterized the first 956 nucleotides located upstream of MUC5B transcription start site and studied the promoter functional activity in colon cancer cells (20). The region is characterized by the presence of a TATA box and numerous putative binding sites for ubiquitous (Sp1) and specific transcription factors (NF-B, c-Myc). The high expression of MUC5B was correlated with the mucus-secreting phenotype of the LS174T colon cancer cell line. Introns 1 and 37 of MUC5B have also been studied in our laboratory because they contain tandemly repeated GA-and GC-rich sequences that
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developmental mucin gene expression in the gastroduodenal tract and accessory digestive glands i stomach a relationship to gastric carcinoma
Journal of Histochemistry and Cytochemistry, 2000Co-Authors: Marie-pierre Buisine, Nicole Porchet, Jean-pierre Aubert, Mariechristine Copin, L Devisme, V Maunoury, Elisabeth Deschodt, Bernard GosselinAbstract:Studies were undertaken to provide information regarding cell-specific expression of mucin genes in stomach and their relation to developmental and neoplastic patterns of epithelial cytodifferentiation. In situ hybridization was used to study mRNA expression of eight mucin genes (MUC1-4, MUC5AC, MUC5B, MUC6, MUC7) in stomach of 13 human embryos and fetuses (8-27 weeks' gestation), comparing these with normal, metaplastic, and neoplastic adult tissues. These investigations have demonstrated that MUC1, MUC4, MUC5AC, MUC5B, and MUC6 are already expressed in the embryonic stomach at 8 weeks of gestation. MUC3 mRNA expression can be observed from 10.5 weeks of gestation. MUC2 is expressed at later stages, concomitant with mucous gland cytodifferentiation. Normal adult stomach is characterized by strong expression of MUC1, MUC5AC, and MUC6, less prominent MUC2, and sporadic MUC3 and MUC4, without MUC5B and MUC7. Intestinal metaplasia is characterized by an intestinal-type pattern with MUC2 and MUC3 mRNA expression. Gastric carcinomas exhibit altered mucin gene expression patterns with disappearance of MUC5AC and MUC6 mRNAs in some tumor glands, abnormal expression of MUC2, and reappearance of MUC5B mRNAs. In conclusion, we have observed that patterns of mucin gene expression in embryonic and fetal stomach could show similarities with some gastric carcinomas in adults. Differences in mucin gene expression in developmental, metaplastic, and neoplastic stomach compared to normal adult stomach suggest a possible regulatory role for their products in gastric epithelial cell proliferation and differentiation.
Marie-pierre Buisine - One of the best experts on this subject based on the ideXlab platform.
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Developmental Patterns of Mucin Gene Expression in Human Fetal Small Intestinal Xenografts Maintained in Severe-Combined Immunodeficient Mice
Pediatric Research, 2003Co-Authors: Marie-pierre Buisine, Jean-pierre Aubert, W Allan Walker, Tor C SavidgeAbstract:The lack of a suitable animal model that expresses human intestinal mucin genes limits the study of mucin function. The aim of this study was to examine whether human fetal intestinal xenografts, known to model host-restricted interactions with human-specific pathogens, express mucin genes in an appropriate developmental pattern when transplanted into severe-combined immunodeficient ( scid ) mice. Expression profiles for eight mucin genes were examined in human fetal ileal xenografts transplanted ectopically into scid mice for 10 wk. In situ hybridization was performed on fetal, xenograft, and adult intestinal tissue sections with ^35S-labeled oligonucleotides specific to human tandem repeat sequences for MUC1 , MUC2 , MUC3 , MUC4 , MUC5AC , MUC5B , MUC6 , and MUC7 . Hybridization patterns observed with the MUC2 , MUC3 , MUC4 , and MUC5AC probes demonstrated that mucin gene expression in xenografted fetal intestine was comparable to third trimester fetal and/or adult tissues. MUC2 and MUC5AC were expressed in a developmental-specific fashion. MUC5AC , expressed in first and early second trimester fetal bowel, was never detected in intestinal xenografts. MUC2 expression displayed a late fetal and/or adult-type hybridization pattern. MUC3 and MUC4 were not developmentally expressed. Appropriate developmental regulation of known intestinal mucin genes was recorded in ectopically grafted human fetal intestinal xenografts. Adult-like patterns of mucin gene expression in this model system will permit future studies aimed at characterizing cis/trans -acting factors that regulate mucin gene expression and function during development, disease, and wound healing and also in mucin-pathogen interactions during host defense.
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Mucin gene expression in intraductal papillary-mucinous pancreatic tumours and related lesions.
The Journal of pathology, 2002Co-Authors: Benoit Terris, Nicole Porchet, Marie-pierre Buisine, Jean-pierre Aubert, Sylvie Dubois, Alain Sauvanet, Philippe Ruszniewski, Anne Couvelard, Claude Degott, Jean-françois FléjouAbstract:Intraductal papillary-mucinous tumours (IPMTs) of the pancreas are heterogeneous proliferations characterized by a malignant potential. The molecular mechanisms underlying the tumourigenesis process are not well understood. Recently, it has been shown that IPMTs secreting the mucin antigen MUC2 have a better prognosis, but the complete pattern of MUC gene expression has not yet been established. The aims of this study were to evaluate the mucin gene expression in 57 IPMTs and eight related lesions surgically resected and to relate MUC gene expression to the histological diagnosis. In situ hybridization (ISH) was performed in 28 cases with probes specific for the MUC1, MUC2, MUC3, MUC4, MUC5AC, MUC5B, MUC6, and MUC7 genes. An immunohistochemical analysis was carried in all 65 cases and in 90 conventional ductal adenocarcinomas of the pancreas using MUC1, MUC2, and MUC5AC antibodies. IPMTs of adenoma (dysplasia) type exhibited high expression of MUC2 (93%), MUC5AC (97%), and, to a lesser extent, of MUC4 (71%), all of which were also observed in colloid carcinomas associated with IPMTs. In contrast, IPMTs with simple hyperplasia, intraductal oncocytic papillary neoplasms, and pyloric glandular adenomas exhibited little or no expression of MUC2. The mucin expression profile supports the existence of two types of invasive tumour associated with IPMTs: a colloid and an ordinary form. The latter shows a pattern similar to the conventional ductal adenocarcinomas with a loss of MUC2 and a gain of MUC1 and has a greater tendency to metastasize. In conclusion, the altered expression of mucin, characteristic of IPMT of adenoma type and of colloid carcinomas, may contribute to the better clinical outcome of these neoplasms, compared to conventional pancreatic ductal adenocarcinomas.
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normal respiratory mucosa precursor lesions and lung carcinomas differential expression of human mucin genes
Frontiers in Bioscience, 2001Co-Authors: Mariechristine Copin, Marie-pierre Buisine, L Devisme, Xavier Leroy, Fabienne Escande, B Gosselin, J P Aubert, Nicole PorchetAbstract:Mucins are glycoproteins synthesized by epithelial cells and thought to promote tumor-cell invasion. Eight human mucin genes have been well characterized: MUC2, MUC5AC, MUC5B, MUC6 map to 11p15.5 and encode secretory gel forming mucins while MUC1, MUC3, MUC4, MUC7 are scattered on different chromosomes and encode membrane-bound or secreted mucins. The expression pattern of the mucin genes is complex in normal airways involving six genes, mainly MUC5AC and MUC5B in mucus-producing cells and MUC4 in a wide array of epithelial cells. MUC5AC overexpression in metaplasia, dysplasia and normal epithelium adjacent to squamous cell carcinoma provides additional arguments for a mucous cell origin of preneoplastic squamous lesions. MUC5AC and MUC5B expression is related to mucus formation in adenocarcinomas. Mucinous bronchioloalveolar carcinoma (BAC) has a particular pattern of mucin gene expression indicating that it has sustained a well-differentiated phenotype similar to the goblet cell, correlated with distinctive features i.e. a noninvasive pattern and a better prognosis than nonBACs. MUC4 is the earlier mucin gene expressed in the foregut, before epithelial differentiation and is expressed independently of mucus secretion both in normal adult airways and carcinomas. These findings are in favor the histogenetic theory of non-small-cell carcinoma originating from a pluripotent mucous cell.
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Aberrant Expression of Human Mucin Gene MUC5B in Gastric Carcinoma and Cancer Cells
Journal of Biological Chemistry, 2001Co-Authors: Michael Perrais, Nicole Porchet, Pascal Pigny, Marie-pierre Buisine, Jean-pierre Aubert, Isabelle Van Seuningen-lempireAbstract:In gastric cancer, altered expression of MUC1, MUC2, MUC5AC, and MUC6 mucin genes has already been described. We show in this report by the means of in situ hybridization, reverse transcriptase-polymerase chain reaction, and transfection assays that MUC5B is also abnormally expressed in gastric carcinomatous tissues and cell lines. We thus undertook to elucidate the molecular mechanisms that regulate the transcription of MUC5B in gastric cancer cells. To this end, high expressing (KATO-III) and low expressing (AGS) gastric cancer cell lines were chosen to study human mucin gene MUC5B expression and promoter activity. Sequencing of the promoter region revealed a distal TATA box located 1 kilobase upstream of the proximal TATA box. Functional activity of the promoter was addressed by using deletion mutants covering 2044 nucleotides upstream of the MUC5B transcription start site. We identified a distal promoter 10 times more active than the proximal promoter in KATO-III cells. In AGS cells, both promoters, much less active, showed the same range of activity. Binding assays allowed us to show that the transcription factor ATF-1 binds to a cis-element present in the distal promoter. Sp1, which binds to both promoters specifically transactivates the proximal promoter. Treatment of transfected cells with PMA, cholera toxin A subunit, and calcium ionophore A23187 showed that only PMA led to a substantial activation of the distal promoter. MUC5B 5-flanking region having a high GC content, influence of methylation on the MUC5B expression was assessed. Our results indicate that repression of MUC5B expression visualized in AGS cells is due in part to the presence of numerous methy-lated cytosine residues throughout the 5-flanking region. Altogether these results demonstrate that MUC5B expression in gastric cancer cells is governed by a highly active distal promoter that is up-regulated by protein kinase C and that repression is under the influence of methylation. Mucins are high molecular weight O-glycoproteins synthesized by epithelial cells as large secreted or membrane-bound glycoproteins (1). So far, eight mucin genes have been well characterized (MUC1, MUC2, MUC3, MUC4, MUC5AC, MUC5B, MUC6, and MUC7) (1), and cDNAs have been proposed for MUC8, MUC9, MUC11, and MUC12 (1, 2). Numerous studies have now demonstrated that the expression of mucin genes is tissue-and cell-specific and that their expression is altered during the pathogenesis of several diseases, which suggests that human mucin gene expression is tightly regulated and that they may play important roles during cell differentiation and carcinogenesis (3-8). In normal stomach, MUC5AC is expressed at the surface/ foveolar epithelium and MUC6 in the mucous neck cells and in the antral glands (9-11). Other mucin genes expressed in normal gastric mucosae are MUC1 and to a lesser extent MUC2, MUC3, and MUC4. In gastric carcinomas, a decrease of MUC1, MUC5AC and MUC6 expression and an increase of MUC2, MUC3, and MUC4 expression has already been demonstrated (11-15). Human mucin gene MUC5B has been extensively studied in our laboratory. Studies of MUC5B genomic sequence (39.1 kb) 1 showed that it encodes a high molecular weight polypeptide (627,000) (16-20). MUC5B mucin gene is localized on chromosome 11 (band p15) and is clustered with three other mucin genes: MUC2, MUC6, and MUC5AC (21). In normal adult, MUC5B is essentially expressed in trachea, bronchi, submax-illary glands, pancreas, gallbladder, and endocervix (4, 22-24). In cancer, MUC5B has been shown to be highly expressed in colon carcinoma (5), in HT-29 treated with methotrexate (19, 20, 25), and LS174T (20, 24, 26) mucus-secreting colon cancer cell lines. We recently characterized the first 956 nucleotides located upstream of MUC5B transcription start site and studied the promoter functional activity in colon cancer cells (20). The region is characterized by the presence of a TATA box and numerous putative binding sites for ubiquitous (Sp1) and specific transcription factors (NF-B, c-Myc). The high expression of MUC5B was correlated with the mucus-secreting phenotype of the LS174T colon cancer cell line. Introns 1 and 37 of MUC5B have also been studied in our laboratory because they contain tandemly repeated GA-and GC-rich sequences that
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developmental mucin gene expression in the gastroduodenal tract and accessory digestive glands i stomach a relationship to gastric carcinoma
Journal of Histochemistry and Cytochemistry, 2000Co-Authors: Marie-pierre Buisine, Nicole Porchet, Jean-pierre Aubert, Mariechristine Copin, L Devisme, V Maunoury, Elisabeth Deschodt, Bernard GosselinAbstract:Studies were undertaken to provide information regarding cell-specific expression of mucin genes in stomach and their relation to developmental and neoplastic patterns of epithelial cytodifferentiation. In situ hybridization was used to study mRNA expression of eight mucin genes (MUC1-4, MUC5AC, MUC5B, MUC6, MUC7) in stomach of 13 human embryos and fetuses (8-27 weeks' gestation), comparing these with normal, metaplastic, and neoplastic adult tissues. These investigations have demonstrated that MUC1, MUC4, MUC5AC, MUC5B, and MUC6 are already expressed in the embryonic stomach at 8 weeks of gestation. MUC3 mRNA expression can be observed from 10.5 weeks of gestation. MUC2 is expressed at later stages, concomitant with mucous gland cytodifferentiation. Normal adult stomach is characterized by strong expression of MUC1, MUC5AC, and MUC6, less prominent MUC2, and sporadic MUC3 and MUC4, without MUC5B and MUC7. Intestinal metaplasia is characterized by an intestinal-type pattern with MUC2 and MUC3 mRNA expression. Gastric carcinomas exhibit altered mucin gene expression patterns with disappearance of MUC5AC and MUC6 mRNAs in some tumor glands, abnormal expression of MUC2, and reappearance of MUC5B mRNAs. In conclusion, we have observed that patterns of mucin gene expression in embryonic and fetal stomach could show similarities with some gastric carcinomas in adults. Differences in mucin gene expression in developmental, metaplastic, and neoplastic stomach compared to normal adult stomach suggest a possible regulatory role for their products in gastric epithelial cell proliferation and differentiation.
Jean-pierre Aubert - One of the best experts on this subject based on the ideXlab platform.
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Developmental Patterns of Mucin Gene Expression in Human Fetal Small Intestinal Xenografts Maintained in Severe-Combined Immunodeficient Mice
Pediatric Research, 2003Co-Authors: Marie-pierre Buisine, Jean-pierre Aubert, W Allan Walker, Tor C SavidgeAbstract:The lack of a suitable animal model that expresses human intestinal mucin genes limits the study of mucin function. The aim of this study was to examine whether human fetal intestinal xenografts, known to model host-restricted interactions with human-specific pathogens, express mucin genes in an appropriate developmental pattern when transplanted into severe-combined immunodeficient ( scid ) mice. Expression profiles for eight mucin genes were examined in human fetal ileal xenografts transplanted ectopically into scid mice for 10 wk. In situ hybridization was performed on fetal, xenograft, and adult intestinal tissue sections with ^35S-labeled oligonucleotides specific to human tandem repeat sequences for MUC1 , MUC2 , MUC3 , MUC4 , MUC5AC , MUC5B , MUC6 , and MUC7 . Hybridization patterns observed with the MUC2 , MUC3 , MUC4 , and MUC5AC probes demonstrated that mucin gene expression in xenografted fetal intestine was comparable to third trimester fetal and/or adult tissues. MUC2 and MUC5AC were expressed in a developmental-specific fashion. MUC5AC , expressed in first and early second trimester fetal bowel, was never detected in intestinal xenografts. MUC2 expression displayed a late fetal and/or adult-type hybridization pattern. MUC3 and MUC4 were not developmentally expressed. Appropriate developmental regulation of known intestinal mucin genes was recorded in ectopically grafted human fetal intestinal xenografts. Adult-like patterns of mucin gene expression in this model system will permit future studies aimed at characterizing cis/trans -acting factors that regulate mucin gene expression and function during development, disease, and wound healing and also in mucin-pathogen interactions during host defense.
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Detection of bone marrow-disseminated breast cancer cells using an RT-PCR assay of MUC5B mRNA.
International journal of cancer, 2002Co-Authors: Nora Berois, Nicole Porchet, Cecilia Sóñora, Mario Varangot, Leticia Zarantonelli, Carlos Pressa, Raúl Laviña, José Luis Rodríguez, Fernando Delgado, Jean-pierre AubertAbstract:The evaluation of disseminated epithelial tumor cells in breast cancer patients has generated considerable interest due to its potential association with disease recurrence. Our work was performed to analyze the usefulness of 5 mucin genes expression (MUC2, MUC3, MUC5B, MUC6 and MUC7), using RT-PCR assays, to detect disseminated cancer cells in patients with operable breast cancer. The highest frequencies of positive RT-PCR tests in breast tumor extracts were observed for MUC5B (7/15) and MUC7 (5/12). The best specificity, negative results on all peripheral blood mononuclear (PBMN) cell samples from healthy donors, were shown for MUC2, MUC5B and MUC6 RT-PCR assays. Thus, we selected MUC5B as a target gene for further evaluation. Using a nested RT-PCR, MUC5B mRNA transcripts were detected in 16/31 primary breast tumors (but not in 36 samples of normal PBMN cells) and in the human MCF-7 breast cancer cell line but not in BT20, MDA, T47D and ZR-75 breast cancer cell lines, indicating that MUC5B mRNA is expressed in a population of breast cancer cells. Using this method, 9/46 patients (19.5%) who underwent curative surgery showed positive MUC5B mRNA in bone marrow aspirates obtained prior to surgery, including 5/24 patients (20.8%) with stage I or II breast cancer, without histopathologic lymph node involvement. These results indicate that MUC5B mRNA could be a specific marker applicable to the molecular diagnosis of breast cancer cell dissemination. A comparative evaluation between MUC5B mRNA, cytokeratin 19 (CK19) mRNA and carcinoembryonic antigen (CEA) mRNA in all bone marrow aspirates suggests a putative complementation for molecular detection of disseminated carcinoma cells. Considering that breast cancer is characterized by a great phenotypic heterogeneity, the use of multimarker approach could contribute to tumor cell detection in bone marrow and blood. © 2002 Wiley-Liss, Inc.
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Mucin gene expression in intraductal papillary-mucinous pancreatic tumours and related lesions.
The Journal of pathology, 2002Co-Authors: Benoit Terris, Nicole Porchet, Marie-pierre Buisine, Jean-pierre Aubert, Sylvie Dubois, Alain Sauvanet, Philippe Ruszniewski, Anne Couvelard, Claude Degott, Jean-françois FléjouAbstract:Intraductal papillary-mucinous tumours (IPMTs) of the pancreas are heterogeneous proliferations characterized by a malignant potential. The molecular mechanisms underlying the tumourigenesis process are not well understood. Recently, it has been shown that IPMTs secreting the mucin antigen MUC2 have a better prognosis, but the complete pattern of MUC gene expression has not yet been established. The aims of this study were to evaluate the mucin gene expression in 57 IPMTs and eight related lesions surgically resected and to relate MUC gene expression to the histological diagnosis. In situ hybridization (ISH) was performed in 28 cases with probes specific for the MUC1, MUC2, MUC3, MUC4, MUC5AC, MUC5B, MUC6, and MUC7 genes. An immunohistochemical analysis was carried in all 65 cases and in 90 conventional ductal adenocarcinomas of the pancreas using MUC1, MUC2, and MUC5AC antibodies. IPMTs of adenoma (dysplasia) type exhibited high expression of MUC2 (93%), MUC5AC (97%), and, to a lesser extent, of MUC4 (71%), all of which were also observed in colloid carcinomas associated with IPMTs. In contrast, IPMTs with simple hyperplasia, intraductal oncocytic papillary neoplasms, and pyloric glandular adenomas exhibited little or no expression of MUC2. The mucin expression profile supports the existence of two types of invasive tumour associated with IPMTs: a colloid and an ordinary form. The latter shows a pattern similar to the conventional ductal adenocarcinomas with a loss of MUC2 and a gain of MUC1 and has a greater tendency to metastasize. In conclusion, the altered expression of mucin, characteristic of IPMT of adenoma type and of colloid carcinomas, may contribute to the better clinical outcome of these neoplasms, compared to conventional pancreatic ductal adenocarcinomas.
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mucin muc gene expression in human pancreatic adenocarcinoma and chronic pancreatitis a potential role of muc4 as a tumor marker of diagnostic significance
Clinical Cancer Research, 2001Co-Authors: Mahefatiana Andrianifahanana, Michael A Hollingsworth, Jean-pierre Aubert, Nicolas Moniaux, Bruno M Schmied, Jorg Ringel, Helmut Friess, Markus W Buchler, Surinder K BatraAbstract:Purpose: Mucins are important biomolecules that frequently display an altered expression under pathological conditions. In a search for a unique and reliable marker(s) specific for pancreatic adenocarcinoma, we investigated the expression of different MUC genes in pancreatic tumors and tumor cell lines, in chronic pancreatitis, and in the normal pancreas. Experimental Design: Total RNA from 16 pancreatic tumors, 10 chronic pancreatitis tissues, 7 normal pancreas tissues, and 15 pancreatic tumor cell lines were analyzed by reverse transcription-PCR with primers specific for MUC1 , MUC2 , MUC3 , MUC4 , MUC5AC , MUC5B , MUC6 , and MUC7 genes and by RNA slot blot analyses. Results: Our results revealed that of all of the mucins examined, only MUC4 displayed a differential expression that was specific for pancreatic adenocarcinoma. Indeed, a substantial number of tumor tissue samples (12 of 16) and tumor cell lines (11 of 15) expressed MUC4 mRNA, whereas samples from chronic pancreatitis (0 of 10) and the normal pancreas (0 of 7) tissues failed to exhibit any detectable level of this mucin. In contrast, no significant alteration was observed in the expression of the other mucins relative to that in the normal pancreas samples. Conclusions: Overall, this work demonstrates that pancreatic mucin MUC4 is a tumor-associated mucin. Furthermore, the present study introduces a novel avenue to discriminate between pancreatic adenocarcinoma and pancreatitis. Future investigations of the role played by MUC4 in pancreatic adenocarcinoma may prove to be useful in the formulation of strategies for the diagnosis and therapeutic treatment of this malignancy.
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Aberrant Expression of Human Mucin Gene MUC5B in Gastric Carcinoma and Cancer Cells
Journal of Biological Chemistry, 2001Co-Authors: Michael Perrais, Nicole Porchet, Pascal Pigny, Marie-pierre Buisine, Jean-pierre Aubert, Isabelle Van Seuningen-lempireAbstract:In gastric cancer, altered expression of MUC1, MUC2, MUC5AC, and MUC6 mucin genes has already been described. We show in this report by the means of in situ hybridization, reverse transcriptase-polymerase chain reaction, and transfection assays that MUC5B is also abnormally expressed in gastric carcinomatous tissues and cell lines. We thus undertook to elucidate the molecular mechanisms that regulate the transcription of MUC5B in gastric cancer cells. To this end, high expressing (KATO-III) and low expressing (AGS) gastric cancer cell lines were chosen to study human mucin gene MUC5B expression and promoter activity. Sequencing of the promoter region revealed a distal TATA box located 1 kilobase upstream of the proximal TATA box. Functional activity of the promoter was addressed by using deletion mutants covering 2044 nucleotides upstream of the MUC5B transcription start site. We identified a distal promoter 10 times more active than the proximal promoter in KATO-III cells. In AGS cells, both promoters, much less active, showed the same range of activity. Binding assays allowed us to show that the transcription factor ATF-1 binds to a cis-element present in the distal promoter. Sp1, which binds to both promoters specifically transactivates the proximal promoter. Treatment of transfected cells with PMA, cholera toxin A subunit, and calcium ionophore A23187 showed that only PMA led to a substantial activation of the distal promoter. MUC5B 5-flanking region having a high GC content, influence of methylation on the MUC5B expression was assessed. Our results indicate that repression of MUC5B expression visualized in AGS cells is due in part to the presence of numerous methy-lated cytosine residues throughout the 5-flanking region. Altogether these results demonstrate that MUC5B expression in gastric cancer cells is governed by a highly active distal promoter that is up-regulated by protein kinase C and that repression is under the influence of methylation. Mucins are high molecular weight O-glycoproteins synthesized by epithelial cells as large secreted or membrane-bound glycoproteins (1). So far, eight mucin genes have been well characterized (MUC1, MUC2, MUC3, MUC4, MUC5AC, MUC5B, MUC6, and MUC7) (1), and cDNAs have been proposed for MUC8, MUC9, MUC11, and MUC12 (1, 2). Numerous studies have now demonstrated that the expression of mucin genes is tissue-and cell-specific and that their expression is altered during the pathogenesis of several diseases, which suggests that human mucin gene expression is tightly regulated and that they may play important roles during cell differentiation and carcinogenesis (3-8). In normal stomach, MUC5AC is expressed at the surface/ foveolar epithelium and MUC6 in the mucous neck cells and in the antral glands (9-11). Other mucin genes expressed in normal gastric mucosae are MUC1 and to a lesser extent MUC2, MUC3, and MUC4. In gastric carcinomas, a decrease of MUC1, MUC5AC and MUC6 expression and an increase of MUC2, MUC3, and MUC4 expression has already been demonstrated (11-15). Human mucin gene MUC5B has been extensively studied in our laboratory. Studies of MUC5B genomic sequence (39.1 kb) 1 showed that it encodes a high molecular weight polypeptide (627,000) (16-20). MUC5B mucin gene is localized on chromosome 11 (band p15) and is clustered with three other mucin genes: MUC2, MUC6, and MUC5AC (21). In normal adult, MUC5B is essentially expressed in trachea, bronchi, submax-illary glands, pancreas, gallbladder, and endocervix (4, 22-24). In cancer, MUC5B has been shown to be highly expressed in colon carcinoma (5), in HT-29 treated with methotrexate (19, 20, 25), and LS174T (20, 24, 26) mucus-secreting colon cancer cell lines. We recently characterized the first 956 nucleotides located upstream of MUC5B transcription start site and studied the promoter functional activity in colon cancer cells (20). The region is characterized by the presence of a TATA box and numerous putative binding sites for ubiquitous (Sp1) and specific transcription factors (NF-B, c-Myc). The high expression of MUC5B was correlated with the mucus-secreting phenotype of the LS174T colon cancer cell line. Introns 1 and 37 of MUC5B have also been studied in our laboratory because they contain tandemly repeated GA-and GC-rich sequences that
Carme De Bolos - One of the best experts on this subject based on the ideXlab platform.
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expression of membrane bound mucins muc1 and muc4 and secreted mucins muc2 muc5ac muc5b muc6 and MUC7 in mucoepidermoid carcinomas of salivary glands
The American Journal of Surgical Pathology, 2005Co-Authors: Llucia Alos, Carme De Bolos, Blanca Lujan, Mireia Castillo, Alfons Nadal, Marta Carreras, Miguel Caballero, Antonio CardesaAbstract:Mucins are glycoproteins normally synthesized by a variety of secretory epithelial cells. The aim of this study was to investigate the expression of mucins (MUC1, MUC2, MUC4, MUC5AC, MUCB, MUC6, MUC7) in mucoepidermoid carcinomas, the most frequent malignant tumor of salivary glands. Forty mucoepidermoid carcinomas and twenty-two normal salivary glands were studied for these mucins by immunohistochemistry from formalin-fixed and paraffin-embedded material. Normal salivary glands frequently expressed MUC1 and MUC4, mainly in ductal cells; MUC5B and MUC7 stained mucous and serous acini respectively of submandibular and minor salivary glands; and MUC5AC and MUC2 were poorly detected in excretory ducts. All mucoepidermoid carcinomas expressed MUC1, and 38/40 tumors expressed MUC4. Both membrane-bound mucins stained membranes and cytoplasm of all cell types (epidermoid, intermediate, mucous, clear and columnar). MUC5AC and MUC5B stained glandular differentiated cells in most tumors (29/40 and 33/40 cases, respectively). MUC6 was positive in 13/40 tumors, and both MUC2 and MUC7 in only 2/40 tumors. The high expression of MUC1 was related to high histologic grades, high recurrence and metastasis rates and a shorter disease-free interval (P < 0.05). Conversely, MUC4 high expression was mainly related to low-grade tumors, lower recurrence rates and a longer disease-free interval (P < 0.05). In conclusion, mucoepidermoid carcinomas of salivary glands usually express MUC1, MUC4, MUC5AC and MUC5B; less frequently MUC6; and rarely MUC2 and MUC7. This mucin expression pattern can be useful for diagnostic purposes. Therefore, MUC1 expression is related to tumor progression and worse prognosis, whereas MUC4 expression is related to a better prognosis.
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mucins as differentiation markers in bronchial epithelium squamous cell carcinoma and adenocarcinoma display similar expression patterns
American Journal of Respiratory Cell and Molecular Biology, 2001Co-Authors: Anna Lopezferrer, Carlos Barranco, Victor Curull, Marta Garrido, Josep Lloreta, Francisco X Real, Carme De BolosAbstract:Highly glycosylated apomucins are important to maintain the viscoelastic properties of the mucus. Changes in their expression are frequently associated with inflammatory and neoplastic conditions. We analyzed the expression of apomucins in normal respiratory tract (n = 8) and compared it with distal, peritumoral, and tumoral epithelia from patients with squamous cell carcinoma (n = 20), adenocarcinoma (n = 13), and small cell carcinoma (n = 12). Squamous metaplasia (n = 16) was also analyzed. MUC1, MUC2, MUC4, MUC5AC, MUC6, and MUC8 apomucins were detected by immunohistochemistry, and mucin transcripts by in situ hybridization and reverse transcriptase polymerase chain reaction. Bronchial epithelium from normal individuals and distal epithelium from cancer patients showed a similar expression pattern: MUC1, MUC4, and MUC8 were always present, MUC2 and MUC5AC showed more variability, and MUC6 was focally detected. MUC5AC was downregulated in peritumoral epithelium and in squamous metaplasia, and MUC6 was u...
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intestinal metaplasia of human stomach displays distinct patterns of mucin muc1 muc2 muc5ac and muc6 expression
Cancer Research, 1999Co-Authors: Celso A. Reis, Leonor David, Pelayo Correa, Fatima Carneiro, Carme De Bolos, Elsa Garcia, Ulla Mandel, Henrik Clausen, Manuel SobrinhosimoesAbstract:Intestinal metaplasia is a well-established premalignant condition of the stomach that is characterized by mucin carbohydrate modifications defined by histochemical methods. The purpose of the present study was to see whether the expression of mucin core proteins was modified in the different types of intestinal metaplasia and to evaluate the putative usefulness of mucins as “molecular markers” in this setting. We used a panel of monoclonal antibodies with well-defined specificities to MUC1, MUC2, MUC5AC, and MUC6 to characterize the expression pattern of mucins. In contrast to normal gastric mucosa, the complete form or type I intestinal metaplasia ( n = 20) displayed little or no expression of MUC1, MUC5AC, or MUC6 in the metaplastic cells and strong expression of the intestinal mucin MUC2 in the goblet cells of all cases. The incomplete forms of intestinal metaplasia, type II ( n = 25) and type III ( n = 16), expressed MUC1 and MUC5AC in every case, both in goblet and in columnar cells. MUC6 was also expressed in 16 cases of type II intestinal metaplasia and in 11 cases of type III intestinal metaplasia. The intestinal mucin MUC2 was expressed in every case of incomplete intestinal metaplasia, mostly in goblet cells. The mucin expression profile in the different types of intestinal metaplasia allows the identification of two patterns: one defined by decreased levels of expression of “gastric” mucins (MUC1, MUC5AC, and MUC6) and expression of MUC2 intestinal mucin, which corresponds to type I intestinal metaplasia, and the other defined by coexpression of “gastric mucins” (MUC1, MUC5AC, and MUC6) together with the MUC2 mucin, encompassing types II and III intestinal metaplasia. Our results challenge the classical sequential pathway of intestinal metaplasia (from type I to type III via a type II intermediate step).
Mariechristine Copin - One of the best experts on this subject based on the ideXlab platform.
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normal respiratory mucosa precursor lesions and lung carcinomas differential expression of human mucin genes
Frontiers in Bioscience, 2001Co-Authors: Mariechristine Copin, Marie-pierre Buisine, L Devisme, Xavier Leroy, Fabienne Escande, B Gosselin, J P Aubert, Nicole PorchetAbstract:Mucins are glycoproteins synthesized by epithelial cells and thought to promote tumor-cell invasion. Eight human mucin genes have been well characterized: MUC2, MUC5AC, MUC5B, MUC6 map to 11p15.5 and encode secretory gel forming mucins while MUC1, MUC3, MUC4, MUC7 are scattered on different chromosomes and encode membrane-bound or secreted mucins. The expression pattern of the mucin genes is complex in normal airways involving six genes, mainly MUC5AC and MUC5B in mucus-producing cells and MUC4 in a wide array of epithelial cells. MUC5AC overexpression in metaplasia, dysplasia and normal epithelium adjacent to squamous cell carcinoma provides additional arguments for a mucous cell origin of preneoplastic squamous lesions. MUC5AC and MUC5B expression is related to mucus formation in adenocarcinomas. Mucinous bronchioloalveolar carcinoma (BAC) has a particular pattern of mucin gene expression indicating that it has sustained a well-differentiated phenotype similar to the goblet cell, correlated with distinctive features i.e. a noninvasive pattern and a better prognosis than nonBACs. MUC4 is the earlier mucin gene expressed in the foregut, before epithelial differentiation and is expressed independently of mucus secretion both in normal adult airways and carcinomas. These findings are in favor the histogenetic theory of non-small-cell carcinoma originating from a pluripotent mucous cell.
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developmental mucin gene expression in the gastroduodenal tract and accessory digestive glands i stomach a relationship to gastric carcinoma
Journal of Histochemistry and Cytochemistry, 2000Co-Authors: Marie-pierre Buisine, Nicole Porchet, Jean-pierre Aubert, Mariechristine Copin, L Devisme, V Maunoury, Elisabeth Deschodt, Bernard GosselinAbstract:Studies were undertaken to provide information regarding cell-specific expression of mucin genes in stomach and their relation to developmental and neoplastic patterns of epithelial cytodifferentiation. In situ hybridization was used to study mRNA expression of eight mucin genes (MUC1-4, MUC5AC, MUC5B, MUC6, MUC7) in stomach of 13 human embryos and fetuses (8-27 weeks' gestation), comparing these with normal, metaplastic, and neoplastic adult tissues. These investigations have demonstrated that MUC1, MUC4, MUC5AC, MUC5B, and MUC6 are already expressed in the embryonic stomach at 8 weeks of gestation. MUC3 mRNA expression can be observed from 10.5 weeks of gestation. MUC2 is expressed at later stages, concomitant with mucous gland cytodifferentiation. Normal adult stomach is characterized by strong expression of MUC1, MUC5AC, and MUC6, less prominent MUC2, and sporadic MUC3 and MUC4, without MUC5B and MUC7. Intestinal metaplasia is characterized by an intestinal-type pattern with MUC2 and MUC3 mRNA expression. Gastric carcinomas exhibit altered mucin gene expression patterns with disappearance of MUC5AC and MUC6 mRNAs in some tumor glands, abnormal expression of MUC2, and reappearance of MUC5B mRNAs. In conclusion, we have observed that patterns of mucin gene expression in embryonic and fetal stomach could show similarities with some gastric carcinomas in adults. Differences in mucin gene expression in developmental, metaplastic, and neoplastic stomach compared to normal adult stomach suggest a possible regulatory role for their products in gastric epithelial cell proliferation and differentiation.
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Developmental Mucin Gene Expression in the Human Respiratory Tract
American journal of respiratory cell and molecular biology, 1999Co-Authors: Marie-pierre Buisine, Jean-pierre Aubert, Mariechristine Copin, L Devisme, Bernard Gosselin, Marc Durand-réville, Nicole PorchetAbstract:The epithelial surface of the respiratory tract is coated with a protective film of mucus secreted by epithelial goblet and submucosal gland cells. Histology of the airway mucosa and composition of secretions during the second trimester of fetal life are known to differ from the normal adult in that these secretions show similarities with those of hypersecretory disorders. To provide information regarding cell-specific expression of mucin genes and their relation to developmental patterns of epithelial cytodifferentiation, we studied the expression of eight different mucin genes (MUC1–MUC4, MUC5AC, MUC5B, MUC6, MUC7) in human embryonic and fetal respiratory tract using in situ hybridization. These investigations demonstrated that MUC4 is the earliest gene expressed in the foregut at 6.5 wk, followed by MUC1 and MUC2 from 9.5 wk of gestation in trachea, bronchi, epithelial tubules, and terminal sacs before epithelial cytodifferentiation. In contrast, MUC5AC, MUC5B, and MUC7 are expressed at later gestation...