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Kusano Y, Horie S, Morishita N, Shibata T, Uchida K. Constitutive expression of an antioxidant enzyme, glutathione S-transferase P1, during differentiation of human intestinal Caco-2 cells. Free Radic Biol Med 2012; 53:347-56. [PMID: 22580340 DOI: 10.1016/j.freeradbiomed.2012.04.032] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2011] [Revised: 04/07/2012] [Accepted: 04/11/2012] [Indexed: 01/29/2023]
Abstract
In this study, we investigated the molecular mechanism of the constitutive expression of an antioxidant enzyme, glutathione S-transferase (GST), during differentiation of human intestinal epithelial Caco-2 cells. We observed that the class π GST isozyme (GST P1) expression correlated with the increased expression of caudal-related homeodomain protein 2 (CDX2), a member of the mammalian homeobox family of transcription factors. In addition, transfection of Caco-2 cells with the human CDX2 cDNA resulted in enhanced expression of the GST P1 gene and protein. Chromatin immunoprecipitation assay demonstrated that CDX2 binds to the GST P1 promoter containing the putative consensus CDX-binding element, TTTAC, located at -247 upstream from the established site for transcription initiation. Using the dsDNA pull-down assay, it was revealed that CDX2 recognized and bound to the putative consensus CDX-binding element within the human GST P1 promoter region and that the amount of the CDX2 bound to the putative consensus CDX-binding element increased during Caco-2 cell differentiation. Furthermore, we demonstrated that CDX2 formed the transcriptional complex with Sp1 and bound to the putative consensus CDX-binding element within the human GST P1 promoter region. These data suggest that CDX2 binds to the human GST P1 promoter via complex formation with Sp1 and controls the constitutive expression of GST P1 during Caco-2 cell differentiation.
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Affiliation(s)
- Yuri Kusano
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya 464-8601, Japan
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52
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Bhat AA, Sharma A, Pope J, Krishnan M, Washington MK, Singh AB, Dhawan P. Caudal homeobox protein Cdx-2 cooperates with Wnt pathway to regulate claudin-1 expression in colon cancer cells. PLoS One 2012; 7:e37174. [PMID: 22719836 PMCID: PMC3376107 DOI: 10.1371/journal.pone.0037174] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2012] [Accepted: 04/17/2012] [Indexed: 11/18/2022] Open
Abstract
Dysregulation of tight junctions (TJs) is often associated with human diseases including carcinogenesis and recent studies support role of TJ integral proteins in the regulation of Epithelial-to-Mesenchymal Transition (EMT). In this regard, expression of claudin-1, a key constituent of TJs, is highly increased in colon cancer and is causally associated with the tumor growth and progression. However, mechanism/s underlying regulation of claudin-1 expression in intestinal epithelial cells remains poorly understood. In our studies, we have identified putative binding sites for intestinal transcription factors Cdx1, -2 and GATA4 in the 5'-flanking region of the claudin-1 gene. Our further studies using full length and/or deletion mutant constructs in two different human colon cancer cell lines, SW480 and HCT116, showed key role of Cdx1, Cdx2 and GATA4 in the regulation of claudin-1 mRNA expression. However, overexpression of Cdx2 had the most potent effect upon claudin-1 mRNA expression and promoter activity. Also, in colon cancer patient samples, we observed a significant and parallel correlation between claudin-1 and Cdx2 expressions. Chromatin immunoprecipitation (ChIP) assay confirmed the Cdx2 binding with claudin-1 promoter in vivo. Using Cdx2 deletion mutant constructs, we further mapped the Cdx2 C-terminus domain to be important in the regulation of claudin-1 promoter activity. Interestingly, co-expression of activated β-catenin further induced the Cdx2-dependent upregulation of claudin-1 promoter activity while expression of the dominant negative (dn)-TCF-4 abrogated this activation. Taken together, we conclude that homeodomain transcription factors Cdx1, Cdx2 and GATA4 regulate claudin-1 gene expression in human colon cancer cells. Moreover, a functional crosstalk between Wnt-signaling and transcriptional activation related to caudal-related homeobox (Cdx) proteins and GATA-proteins is demonstrated in the regulation of claudin-1 promoter-activation.
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Affiliation(s)
- Ajaz A. Bhat
- Department of Surgery, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America
| | - Ashok Sharma
- Department of Surgery, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America
| | - Jillian Pope
- Department of Surgery, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America
- Department of Cancer Biology, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America
| | - Moorthy Krishnan
- Department of Surgery, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America
| | - Mary K. Washington
- Department of Pathology, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America
| | - Amar B. Singh
- Department of Surgery, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America
| | - Punita Dhawan
- Department of Surgery, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America
- Department of Cancer Biology, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America
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53
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Wang L, Hara K, Van Baaren JM, Price JC, Beecham GW, Gallins PJ, Whitehead PL, Wang G, Lu C, Slifer MA, Züchner S, Martin ER, Mash D, Haines JL, Pericak-Vance MA, Gilbert JR. Vitamin D receptor and Alzheimer's disease: a genetic and functional study. Neurobiol Aging 2012; 33:1844.e1-9. [PMID: 22306846 DOI: 10.1016/j.neurobiolaging.2011.12.038] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2011] [Revised: 12/22/2011] [Accepted: 12/28/2011] [Indexed: 11/24/2022]
Abstract
Genetic studies on late-onset Alzheimer's disease (AD) have repeatedly mapped susceptibility loci onto chromosome 12q13, encompassing the vitamin D receptor (VDR) gene. Epidemiology studies have indicated vitamin D insufficiency as a risk factor for AD. Given that VDR is the major mediator for vitamin D's actions, we sought to clarify the role of VDR in late-onset AD. We conducted an association study in 492 late-onset AD cases and 496 controls with 80 tagging single nucleotide polymorphisms (SNPs). The strongest association was found at a promoter SNP rs11568820 (P = 9.1 × 10(-6), odds ratio (OR) = 1.69), which resides within the transcription factor Cdx-2 binding site and the SNP has been also known as CDX2. The risk-allele at rs11568820 is associated with lower VDR promoter activity (p < 10(-11)). The overexpression of VDR or vitamin D treatment suppressed amyloid precursor protein (APP) transcription in neuroblastoma cells (p < 0.001). We provide both statistical evidence and functional data suggesting VDR confers genetic risk for AD. Our findings are consistent with epidemiology studies suggesting that vitamin D insufficiency increases the risk of developing AD.
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Affiliation(s)
- Liyong Wang
- Hussman Institute for Human Genomics, University of Miami Miller School of Medicine 1501 NW 10 Ave, Miami, Florida, USA
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Coskun M, Olsen AK, Holm TL, Kvist PH, Nielsen OH, Riis LB, Olsen J, Troelsen JT. TNF-α-induced down-regulation of CDX2 suppresses MEP1A expression in colitis. Biochim Biophys Acta Mol Basis Dis 2012; 1822:843-51. [PMID: 22326557 DOI: 10.1016/j.bbadis.2012.01.012] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2011] [Revised: 01/24/2012] [Accepted: 01/25/2012] [Indexed: 12/17/2022]
Abstract
BACKGROUND/AIMS High levels of pro-inflammatory cytokines are linked to inflammatory bowel disease (IBD). The transcription factor Caudal-related homeobox transcription factor 2 (CDX2) plays a crucial role in differentiation of intestinal epithelium and regulates IBD-susceptibility genes, including meprin 1A (MEP1A). The aim was to investigate the expression of CDX2 and MEP1A in colitis; to assess if they are regulated by tumor necrosis factor-α (TNF-α), and finally to reveal if CDX2 is involved in a TNF-α-induced down-regulation of MEP1A. METHODS Expression of CDX2 and MEP1A was investigated in colonic biopsies of ulcerative colitis (UC) patients and in dextran sodium sulfate (DSS)-induced colitis. CDX2 protein expression was investigated by immunoblotting and immunohistochemical procedures. CDX2 and MEP1A regulation was examined in TNF-α-treated Caco-2 cells by reverse transcription-polymerase chain reaction and with reporter gene assays, and the effect of anti-TNF-α treatment was assessed using infliximab. Finally, in vivo CDX2-DNA interactions were investigated by chromatin immunoprecipitation. RESULTS The CDX2 and MEP1A mRNA expression was significantly decreased in active UC patients and in DSS-colitis. Colonic biopsy specimens from active UC showed markedly decreased CDX2 staining. TNF-α treatment diminished the CDX2 and MEP1A mRNA levels, a decrease which, was counteracted by infliximab treatment. Reporter gene assays showed significantly reduced CDX2 and MEP1A activity upon TNF-α stimulation. Finally, TNF-α impaired the ability of CDX2 to interact and activate its own, as well as the MEP1A expression. CONCLUSIONS The present results indicate that a TNF-α-mediated down-regulation of CDX2 can be related to suppressed expression of MEP1A during intestinal inflammation.
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Affiliation(s)
- Mehmet Coskun
- Department of Gastroenterology, Medical Section, Herlev Hospital, University of Copenhagen, Herlev, Denmark.
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55
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Olsen AK, Boyd M, Danielsen ET, Troelsen JT. Current and emerging approaches to define intestinal epithelium-specific transcriptional networks. Am J Physiol Gastrointest Liver Physiol 2012; 302:G277-86. [PMID: 22094602 DOI: 10.1152/ajpgi.00362.2011] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Upon developmental or environmental cues, the composition of transcription factors in a transcriptional regulatory network is deeply implicated in controlling the signature of the gene expression and thereby specifies the cell or tissue type. Novel methods including ChIP-chip and ChIP-Seq have been applied to analyze known transcription factors and their interacting regulatory DNA elements in the intestine. The intestine is an example of a dynamic tissue where stem cells in the crypt proliferate and undergo a differentiation process toward the villus. During this differentiation process, specific regulatory networks of transcription factors are activated to target specific genes, which determine the intestinal cell fate. The expanding genomewide mapping of transcription factor binding sites and construction of transcriptional regulatory networks provide new insight into how intestinal differentiation occurs. This review summarizes the current overview of the transcriptional regulatory networks driving epithelial differentiation in adult intestine. The novel technologies that have been implied to study these networks are presented and their prospects for implications in future research are also addressed.
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Affiliation(s)
- Anders Krüger Olsen
- Department of Cellular and Molecular Medicine, University of Copenhagen, Copenhagen, Denmark
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56
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Grainger S, Lam J, Savory JGA, Mears AJ, Rijli FM, Lohnes D. Cdx regulates Dll1 in multiple lineages. Dev Biol 2011; 361:1-11. [PMID: 22015720 DOI: 10.1016/j.ydbio.2011.09.034] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2011] [Revised: 09/21/2011] [Accepted: 09/23/2011] [Indexed: 02/07/2023]
Abstract
Vertebrate Cdx genes encode homeodomain transcription factors related to caudal in Drosophila. The murine Cdx homologues Cdx1, Cdx2 and Cdx4 play important roles in anterior-posterior patterning of the embryonic axis and the intestine, as well as axial elongation. While our understanding of the ontogenic programs requiring Cdx function has advanced considerably, the molecular bases underlying these functions are less well understood. In this regard, Cdx1-Cdx2 conditional mutants exhibit abnormal somite formation, while loss of Cdx1-Cdx2 in the intestinal epithelium results in a shift in differentiation toward the Goblet cell lineage. The aim of the present study was to identify the Cdx-dependent mechanisms impacting on these events. Consistent with prior work implicating Notch signaling in these pathways, we found that expression of the Notch ligand Dll1 was reduced in Cdx mutants in both the intestinal epithelium and paraxial mesoderm. Cdx members occupied the Dll1 promoter both in vivo and in vitro, while genetic analysis indicated interaction between Cdx and Dll1 pathways in both somitogenesis and Goblet cell differentiation. These findings suggest that Cdx members operate upstream of Dll1 to convey different functions in two distinct lineages.
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Affiliation(s)
- Stephanie Grainger
- Department of Cellular and Molecular Medicine, University of Ottawa, 451 Smyth Road, Ottawa, Ontario, Canada
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57
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Lemieux E, Boucher MJ, Mongrain S, Boudreau F, Asselin C, Rivard N. Constitutive activation of the MEK/ERK pathway inhibits intestinal epithelial cell differentiation. Am J Physiol Gastrointest Liver Physiol 2011; 301:G719-30. [PMID: 21737780 DOI: 10.1152/ajpgi.00508.2010] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The Ras/Raf/MEK/ERK cascade regulates intestinal epithelial cell proliferation. Indeed, while barely detectable in differentiated cells of the villi, ERK1/2-activated forms are detected in the nucleus of undifferentiated human intestinal crypt cells. In addition, we and others have reported that ERKs are selectively inactivated during enterocyte differentiation. However, whether inactivation of the ERK pathway is necessary for inhibition of both proliferation and induction of differentiation of intestinal epithelial cells is unknown. Human Caco-2/15 cells, undifferentiated crypt IEC-6 cells, and differentiating Cdx3-expressing IEC-6 cells were infected with retroviruses encoding either a hemagglutinin (HA)-tagged MEK1 wild type (wtMEK) or a constitutively active S218D/S222D MEK1 mutant (caMEK). Protein and gene expression was assessed by Western blotting, semiquantitative RT-PCR, and real-time PCR. Morphology was analyzed by transmission electron microscopy. We found that 1) IEC-6/Cdx3 cells formed multicellular layers after confluence and differentiated after 30 days in culture, as assessed by increased polarization, microvilli formation, expression of differentiation markers, and ERK1/2 inhibition; 2) while activated MEK prevented neither the inhibition of ERK1/2 activities nor the differentiation process in postconfluent Caco-2/15 cells, caMEK expression prevented ERK inhibition in postconfluent IEC-6/Cdx3 cells, thus leading to maintenance of elevated ERK1/2 activities; 3) caMEK-expressing IEC-6/Cdx3 cells exhibited altered multicellular structure organization, poorly defined tight junctions, reduced number of microvilli on the apical surface, and decreased expression of the hepatocyte nuclear factor 1α transcription factor and differentiation markers, namely apolipoprotein A-4, fatty acid-binding protein, calbindin-3, mucin 2, alkaline phosphatase, and sucrase-isomaltase; and 4) increased Cdx3 phosphorylation on serine-60 (S60) in IEC-6/Cdx3 cells expressing caMEK led to decreased Cdx2 transactivation potential. These results indicate that inactivation of the ERK pathway is required to ensure the full Cdx2/3 transcriptional activity necessary for intestinal epithelial cell terminal differentiation.
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Affiliation(s)
- Etienne Lemieux
- Canadian Institutes of Health Research Team on Digestive Epithelium, Department of Anatomy and Cellular Biology, Quebec
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58
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Park SY, Jeong MS, Jang SB. Binding Properties and Structural Predictions of Homeodomain Proteins CDX1/2 and HOXD8. B KOREAN CHEM SOC 2011. [DOI: 10.5012/bkcs.2011.32.7.2325] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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59
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Cell lineage dynamics in the process leading to intestinal metaplasia. J Gastroenterol 2011; 46:620-8. [PMID: 21384254 DOI: 10.1007/s00535-011-0391-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/19/2010] [Accepted: 01/30/2011] [Indexed: 02/04/2023]
Abstract
BACKGROUND Gene expression in the early stage of the transition to intestinal metaplasia in human gastric mucosa has not been determined. In this study, we investigated the temporal relationship between cell lineage changes and intestine-specific gene expression in the process leading to intestinal metaplasia, using Cdx2-transgenic mice. METHODS Cellular phenotypes were analyzed by immunohistochemistry and were compared with the gene expression profiles of cell lineage markers by real-time polymerase chain reaction. RESULTS Up to postnatal day (PD) 20, the gastric mucosae of Cdx2-transgenic mice were histologically similar to those of their normal littermates. However, at approximately PD 20, we observed the sporadic appearance of glands in which all the epithelial cells expressed Cdx2 (Cdx2-diffuse positive glands). In the Cdx2-diffuse positive glands, parietal cells had disappeared, the proliferating zone had moved from the isthmus to the base, and absorptive cells and goblet cells were recognized. In contrast, the surrounding mucosa retained the phenotype of the gastric gland in which only some of the epithelial cells expressed Cdx2. During PDs 30 and 40, the entire fundic mucosa changed to transdifferentiated mucosa that was a composite of intestinal metaplasia and spasmolytic polypeptide-expressing metaplasia. An increase in the expression of intestine-specific genes, with a reciprocal decrease in gastric-specific gene expression, began much earlier than the emergence of Cdx2-diffuse positive glands. CONCLUSIONS A dramatic increase in intestine-specific gene expression precedes the morphological appearance of intestinal metaplasia and spasmolytic polypeptide-expressing metaplasia.
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60
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Kang JM, Lee BH, Kim N, Lee HS, Lee HE, Park JH, Kim JS, Jung HC, Song IS. CDX1 and CDX2 expression in intestinal metaplasia, dysplasia and gastric cancer. J Korean Med Sci 2011; 26:647-53. [PMID: 21532856 PMCID: PMC3082117 DOI: 10.3346/jkms.2011.26.5.647] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/15/2010] [Accepted: 03/15/2011] [Indexed: 12/16/2022] Open
Abstract
Intestinal metaplasia (IM) has been regarded as a premalignant condition. However, the pathogenesis of IM is not fully understood. The aim of this study was to evaluate the role of CDX1 and CDX2 in the formation of IM and the progression to dysplasia and gastric cancer (GC). A total of 270 subjects included 90 with GC, dysplasia and age- and sex-matched controls. Real-time PCR (RT-PCR) was performed with body specimens for CDX1 and CDX2. The expression of CDX2 was significantly higher in H. pylori positive group than H. pylori negative group (P = 0.045). CDX1 and CDX2 expression increased proportional to the IM grade of the body (P < 0.001). CDX2 expression was significantly higher in incomplete type of IM than in complete type (P = 0.045). The expression of CDX1 in dysplasia group was significantly higher than in the control group (P = 0.001); in addition, CDX1 and CDX2 in cancer group was significantly higher than control group (P < 0.001, and P < 0.001, respectively). Aberrant expression of CDX1 and CDX2 correlated with H. pylori infection and grade of IM in the body. Furthermore, the results suggest that CDX1 and CDX2 play a role in the progression to GC and dysplasia.
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Affiliation(s)
- Jung Mook Kang
- Healthcare Research Institute, Seoul National University Hospital Healthcare System Gangnam Center, Seoul, Korea
| | - Byoung Hwan Lee
- Department of Internal Medicine, Seoul National University Bundang Hospital, Seongnam, Korea
| | - Nayoung Kim
- Department of Internal Medicine, Seoul National University Bundang Hospital, Seongnam, Korea
- Department of Internal Medicine and Liver Research Institute, Seoul National University College of Medicine, Seoul, Korea
| | - Hye Seung Lee
- Department of Pathology, Seoul National University Bundang Hospital, Seongnam, Korea
| | - Hee Eun Lee
- Department of Pathology, Seoul National University Bundang Hospital, Seongnam, Korea
| | - Ji Hyun Park
- Department of Internal Medicine and Liver Research Institute, Seoul National University College of Medicine, Seoul, Korea
| | - Joo Sung Kim
- Department of Internal Medicine and Liver Research Institute, Seoul National University College of Medicine, Seoul, Korea
| | - Hyun Chae Jung
- Department of Internal Medicine and Liver Research Institute, Seoul National University College of Medicine, Seoul, Korea
| | - In Sung Song
- Department of Internal Medicine and Liver Research Institute, Seoul National University College of Medicine, Seoul, Korea
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Effects of Homeodomain Protein CDX2 Expression on the Proliferation and Migration of Lovo Colon Cancer Cells. Pathol Oncol Res 2011; 17:743-51. [DOI: 10.1007/s12253-011-9380-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/14/2010] [Accepted: 02/07/2011] [Indexed: 02/04/2023]
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Kong J, Crissey MA, Funakoshi S, Kreindler JL, Lynch JP. Ectopic Cdx2 expression in murine esophagus models an intermediate stage in the emergence of Barrett's esophagus. PLoS One 2011; 6:e18280. [PMID: 21494671 PMCID: PMC3071814 DOI: 10.1371/journal.pone.0018280] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2010] [Accepted: 02/24/2011] [Indexed: 01/27/2023] Open
Abstract
Barrett's esophagus (BE) is an intestinal metaplasia that occurs in the setting of chronic acid and bile reflux and is associated with a risk for adenocarcinoma. Expression of intestine-specific transcription factors in the esophagus likely contributes to metaplasia development. Our objective was to explore the effects of an intestine-specific transcription factor when expressed in the mouse esophageal epithelium. Transgenic mice were derived in which the transcription factor Cdx2 is expressed in squamous epithelium using the murine Keratin-14 gene promoter. Effects of the transgene upon cell proliferation and differentiation, gene expression, and barrier integrity were explored. K14-Cdx2 mice express the Cdx2 transgene in esophageal squamous tissues. Cdx2 expression was associated with reduced basal epithelial cell proliferation and altered cell morphology. Ultrastructurally two changes were noted. Cdx2 expression was associated with dilated space between the basal cells and diminished cell-cell adhesion caused by reduced Desmocollin-3 mRNA and protein expression. This compromised epithelial barrier function, as the measured trans-epithelial electrical resistance (TEER) of the K14-Cdx2 epithelium was significantly reduced compared to controls (1189 Ohm*cm(2) ±343.5 to 508 Ohm*cm(2)±92.48, p = 0.0532). Secondly, basal cells with features of a transitional cell type, intermediate between keratinocytes and columnar Barrett's epithelial cells, were observed. These cells had reduced keratin bundles and increased endoplasmic reticulum levels, suggesting the adoption of secretory-cell features. Moreover, at the ultrastructural level they resembled "Distinctive" cells associated with multilayered epithelium. Treatment of the K14-Cdx2 mice with 5'-Azacytidine elicited expression of BE-associated genes including Cdx1, Krt18, and Slc26a3/Dra, suggesting the phenotype could be advanced under certain conditions. We conclude that ectopic Cdx2 expression in keratinocytes alters cell proliferation, barrier function, and differentiation. These altered cells represent a transitional cell type between normal squamous and columnar BE cells. The K14-Cdx2 mice represent a useful model to study progression from squamous epithelium to BE.
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Affiliation(s)
- Jianping Kong
- Division of Gastroenterology, Department of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Mary Ann Crissey
- Division of Gastroenterology, Department of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Shinsuke Funakoshi
- Division of Gastroenterology, Department of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - James L. Kreindler
- Division of Pulmonary Medicine, Department of Pediatrics, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, United States of America
| | - John P. Lynch
- Division of Gastroenterology, Department of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
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63
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Meera A, Rangarajan L, Bhat S. Computational approach towards promoter sequence comparison via TF mapping using a new distance measure. Interdiscip Sci 2011; 3:43-49. [PMID: 21369887 DOI: 10.1007/s12539-011-0057-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2009] [Revised: 10/20/2009] [Accepted: 10/23/2009] [Indexed: 05/30/2023]
Abstract
We propose a method for identifying transcription factor binding sites (TFBS) in the given promoter sequence and mapping the transcription factors (TFs). The proposed algorithm searches the +1 transcription start site (TSS) for eukaryotic and prokaryotic sequences individually. The algorithm was tested with sequences from both eukaryotes and prokaryotes for at least 9 experimentally verified and validated functional TFs in promoter sequences. The order and type of TF binding to the promoter of genes encoding central metabolic pathway (CMP) enzyme was tabulated. A new similarity measure was devised for scoring the similarity between a pair of promoter sequences based on the number and order of motifs. Further, these were grouped in clusters considering the scores between them. The distance between each of the clusters in individual pathway was calculated and a phylogenetic tree was developed. This method is further applied to other pathways such as lipid and amino acid biosynthesis to retrieve and compare experimentally verified and conserved TFBS.
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Affiliation(s)
- A Meera
- B.M.S College of Engineering, Bull Temple Road, Bangalore, 560019, India
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64
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Barros R, da Costa LT, Pinto-de-Sousa J, Duluc I, Freund JN, David L, Almeida R. CDX2 autoregulation in human intestinal metaplasia of the stomach: impact on the stability of the phenotype. Gut 2011; 60:290-8. [PMID: 21148572 PMCID: PMC3034084 DOI: 10.1136/gut.2010.222323] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND AND AIMS Intestinal metaplasia (IM) is a gastric preneoplastic lesion that appears following Helicobacter pylori infection and confers an increased risk for development of cancer. It is induced by gastric expression of the intestine-specific transcription factor CDX2. The regulatory mechanisms involved in triggering and maintaining gastric CDX2 expression have not been fully elucidated. The Cdx2(+/-) mouse develops intestinal polyps with gastric differentiation and total loss of Cdx2 expression in the absence of structural loss of the second allele, suggesting a regulatory defect. This putative haplo-insufficiency, together with the apparent stability of IM, led to the hypothesis that CDX2 regulates its own expression through an autoregulatory loop in both contexts. METHODS Gastrointestinal cell lines were co-transfected with wild-type or mutated Cdx2 promoter constructs and CDX2 expression vector for luciferase assays. Transfection experiments were also used to assess endogenous CDX2 autoregulation, evaluated by RT-PCR, qPCR and western blotting. Chromatin immunoprecipitation was performed in a cell line, mouse ileum and human IM. RESULTS CDX2 binds to and transactivates its own promoter and positively regulates its expression in gastrointestinal human carcinoma cell lines. Furthermore, CDX2 is bound to its promoter in the mouse ileum and in human gastric IM, providing a major contribution to understanding the relevance of this autoregulatory pathway in vivo. CONCLUSION The results of this study demonstrate another layer of complexity in CDX2 regulation by an effective autoregulatory loop which may have a major impact on the stability of human IM, possibly resulting in the inevitable progression of the gastric carcinogenesis pathway.
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Affiliation(s)
- Rita Barros
- Institute of Molecular Pathology and Immunology of the University of Porto, Porto, Portugal
| | - Luis Teixeira da Costa
- Institute of Molecular Pathology and Immunology of the University of Porto, Porto, Portugal,ICAAM, Universidade de Évora, Évora, Portugal
| | - João Pinto-de-Sousa
- Department of Surgery, Hospital S. João, Porto, Portugal,Faculty of Medicine of the University of Porto, Porto, Portugal
| | | | | | - Leonor David
- Institute of Molecular Pathology and Immunology of the University of Porto, Porto, Portugal,Faculty of Medicine of the University of Porto, Porto, Portugal
| | - Raquel Almeida
- Institute of Molecular Pathology and Immunology of the University of Porto, Porto, Portugal,Faculty of Medicine of the University of Porto, Porto, Portugal
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65
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Li QL, Yang ZL, Liu JQ, Miao XY. Expression of CDX2 and hepatocyte antigen in benign and malignant lesions of gallbladder and its correlation with histopathologic type and clinical outcome. Pathol Oncol Res 2011; 17:561-8. [PMID: 21221877 PMCID: PMC3158976 DOI: 10.1007/s12253-010-9346-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/27/2010] [Accepted: 12/01/2010] [Indexed: 12/17/2022]
Abstract
Recent studies have shown that both CDX2 and Hepatocyte antigen (Hep) are detected in different types of cancer and associated with clinical prognosis. However, fever studies have examined gallbladder cancer specimens, and little is known about the clinicopathological significance of both CDX2 and Hep expression in gallbladder adenocarcinomas. In present study, we examined the expression frequencies of CDX2 and Hepatocyte antigen (Hep), and explored their clinicopathologic significances in gallbladder adenocarcinoma. Immunohistochemistry was used to detect and compare the frequencies of CDX2 and Hep expression in 108 samples of gallbladder adenocarcinoma, 46 peri-tumor tissues and 35 chronic cholecystitis. The expression frequencies for CDX2 and Hep were 49/108 (45.4%) and 45/108 (41.7%) in gallbladder carcinoma; 13/46 (28.3%) and 11/46 (23.9) in peri-tumor tissues; 5/35 (14.3%) and 2/35 (5.7%) in chronic cholecystitis. The positive staining of CDX2 or Hep in gallbladder adenocarcinoma was significantly higher than that in peritumoral tissues (both, P < 0.05), and chronic cholecystits (both, P < 0.01). The expression of CDX2 or Hep was negatively correlated to grade of differentiation, tumor size and lymph node metastasis (P < 0.01 or P < 0.05). Elevated expression frequency of CDX2 or Hep was associated with increased overall survival (P = 0.003 or P = 0.002). Multivariate Cox regression analysis showed that CDX2 (P = 0.014) or Hep (P = 0.026) expression was an independent prognostic predictor in gallbladder adenocarcinoma. CDX2 and Hep might function as important biological markers in the development and prognosis of gallbladder adenocarcinoma.
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Affiliation(s)
- Qing-Long Li
- The Second Xiangya Hospital of Central South University, Changsha, Hunan, China
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66
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Wu G, Gentile L, Fuchikami T, Sutter J, Psathaki K, Esteves TC, Araúzo-Bravo MJ, Ortmeier C, Verberk G, Abe K, Schöler HR. Initiation of trophectoderm lineage specification in mouse embryos is independent of Cdx2. Development 2010; 137:4159-69. [PMID: 21098565 DOI: 10.1242/dev.056630] [Citation(s) in RCA: 100] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The separation of the first two lineages - trophectoderm (TE) and inner cell mass (ICM) - is a crucial event in the development of the early embryo. The ICM, which constitutes the pluripotent founder cell population, develops into the embryo proper, whereas the TE, which comprises the surrounding outer layer, supports the development of the ICM before and after implantation. Cdx2, the first transcription factor expressed specifically in the developing TE, is crucial for the differentiation of cells into the TE, as lack of zygotic Cdx2 expression leads to a failure of embryos to hatch and implant into the uterus. However, speculation exists as to whether maternal Cdx2 is required for initiation of TE lineage separation. Here, we show that effective elimination of both maternal and zygotic Cdx2 transcripts by an RNA interference approach resulted in failure of embryo hatching and implantation, but the developing blastocysts exhibited normal gross morphology, indicating that TE differentiation had been initiated. Expression of keratin 8, a marker for differentiated TE, further confirmed the identity of the TE lineage in Cdx2-deficient embryos. However, these embryos exhibited low mitochondrial activity and abnormal ultrastructure, indicating that Cdx2 plays a key role in the regulation of TE function. Furthermore, we found that embryonic compaction does not act as a 'switch' regulator to turn on Cdx2 expression. Our results clearly demonstrate that neither maternal nor zygotic Cdx2 transcripts direct the initiation of ICM/TE lineage separation.
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Affiliation(s)
- Guangming Wu
- Department of Cell and Developmental Biology, Max Planck Institute for Molecular Biomedicine, Röntgenstrasse 20, 48149 Münster, Germany
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67
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The role of CDX2 in intestinal homeostasis and inflammation. Biochim Biophys Acta Mol Basis Dis 2010; 1812:283-9. [PMID: 21126581 DOI: 10.1016/j.bbadis.2010.11.008] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2010] [Revised: 11/19/2010] [Accepted: 11/22/2010] [Indexed: 12/17/2022]
Abstract
Many transcription factors are known to control transcription at several promoters, while others are only active at a few places. However, due to their importance in controlling cellular functions, aberrant transcription factor function and inappropriate gene regulation have been shown to play a causal role in a large number of diseases and developmental disorders. Inflammatory bowel disease (IBD) is characterized by a chronically inflamed mucosa caused by dysregulation of the intestinal immune homeostasis. The aetiology of IBD is thought to be a combination of genetic and environmental factors, including luminal bacteria. The Caudal-related homeobox transcription factor 2 (CDX2) is critical in early intestinal differentiation and has been implicated as a master regulator of the intestinal homeostasis and permeability in adults. When expressed, CDX2 modulates a diverse set of processes including cell proliferation, differentiation, cell adhesion, migration, and tumorigenesis. In addition to these critical cellular processes, there is increasing evidence for linking CDX2 to intestinal inflammation. The aim of the present paper was to review the current knowledge of CDX2 in regulation of the intestinal homeostasis and further to reveal its potential role in inflammation.
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68
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Sturgeon K, Kaneko T, Biemann M, Gauthier A, Chawengsaksophak K, Cordes SP. Cdx1 refines positional identity of the vertebrate hindbrain by directly repressing Mafb expression. Development 2010; 138:65-74. [PMID: 21098558 DOI: 10.1242/dev.058727] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
An interplay of transcription factors interprets signalling pathways to define anteroposterior positions along the vertebrate axis. In the hindbrain, these transcription factors prompt the position-appropriate appearance of seven to eight segmental structures, known as rhombomeres (r1-r8). The evolutionarily conserved Cdx caudal-type homeodomain transcription factors help specify the vertebrate trunk and tail but have not been shown to directly regulate hindbrain patterning genes. Mafb (Kreisler, Krml1, valentino), a basic domain leucine zipper transcription factor, is required for development of r5 and r6 and is the first gene to show restricted expression within these two segments. The homeodomain protein vHnf1 (Hnf1b) directly activates Mafb expression. vHnf1 and Mafb share an anterior expression limit at the r4/r5 boundary but vHnf1 expression extends beyond the posterior limit of Mafb and, therefore, cannot establish the posterior Mafb expression boundary. Upon identifying regulatory sequences responsible for posterior Mafb repression, we have used in situ hybridization, immunofluorescence and chromatin immunoprecipitation (ChIP) analyses to determine that Cdx1 directly inhibits early Mafb expression in the neural tube posterior of the r6/r7 boundary, which is the anteriormost boundary of Cdx1 expression in the hindbrain. Cdx1 dependent repression of Mafb is transient. After the 10-somite stage, another mechanism acts to restrict Mafb expression in its normal r5 and r6 domain, even in the absence of Cdx1. Our findings identify Mafb as one of the earliest direct targets of Cdx1 and show that Cdx1 plays a direct role in early hindbrain patterning. Thus, just as Cdx2 and Cdx4 govern the trunk-to-tail transition, Cdx1 may regulate the hindbrain-to-spinal cord transition.
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Affiliation(s)
- Kendra Sturgeon
- Samuel Lunenfeld Research Institute, Mount Sinai Hospital, 600 University Avenue, Toronto, ON M5G 1X5, Canada
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69
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Sakamoto H, Mutoh H, Sugano K. Expression of Claudin-2 in intestinal metaplastic mucosa of Cdx2-transgenic mouse stomach. Scand J Gastroenterol 2010; 45:1273-80. [PMID: 20602571 DOI: 10.3109/00365521.2010.501522] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
OBJECTIVE Cdx2 is expressed in human intestinal metaplastic mucosa and induces intestinal metaplastic mucosa in Cdx2-transgenic mouse stomach. Claudin-2 is a structural component of tight junctions in the intestine and Cdx2 activates the Claudin-2 promoter in the human intestinal epithelial cell line Caco-2. Our aim is to evaluate the expression of Claudin-2 in intestinal metaplastic mucosa of Cdx2-transgenic mouse stomach. MATERIAL AND METHODS The Claudin-2 expression in the normal gastric mucosa and normal intestinal mucosa of wild type mice and the intestinal metaplastic mucosa of Cdx2-transgenic mice was analyzed by immunohistochemistry, Western blotting and quantitative real-time PCR (qRT-PCR). RESULTS Claudin-2 was expressed in the base of the glands in intestine and intestinal metaplasia while it was not expressed in the body of stomach. Claudin-2 expression was found in the antrum of stomach, while it was weaker than that in the intestine and the intestinal metaplasia. Claudin-2 was also detected in intestinal metaplasia, colon and ileum by both Western blotting and qRT-PCR while it was not detected in gastric body. CONCLUSION These results suggest that Cdx2 plays an important role in the expression of Claudin-2 in vivo.
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Affiliation(s)
- Hirotsugu Sakamoto
- Department of Medicine, Division of Gastroenterology, Jichi Medical University, Shimotsuke, Tochigi, Japan
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70
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Funakoshi S, Kong J, Crissey MA, Dang L, Dang D, Lynch JP. Intestine-specific transcription factor Cdx2 induces E-cadherin function by enhancing the trafficking of E-cadherin to the cell membrane. Am J Physiol Gastrointest Liver Physiol 2010; 299:G1054-67. [PMID: 20671195 PMCID: PMC2993167 DOI: 10.1152/ajpgi.00297.2010] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Cdx2 is an intestine-specific transcription factor required for normal intestinal epithelium development. Cdx2 regulates the expression of intestine-specific genes and induces cell adhesion and columnar morphogenesis. Cdx2 also has tumor-suppressor properties, including the reduction of colon cancer cell proliferation and cell invasion, the latter due to its effects on cell adhesion. E-cadherin is a cell adhesion protein required for adherens junction formation and the establishment of intestinal cell polarity. The objective of this study was to elucidate the mechanism by which Cdx2 regulates E-cadherin function. Two colon cancer cell lines were identified in which Cdx2 expression was associated with increased cell-cell adhesion and diminished cell migration. In both cell lines, Cdx2 did not directly alter E-cadherin levels but increased its trafficking to the cell membrane compartment. Cdx2 enhanced this trafficking by altering receptor tyrosine kinase (RTK) activity. Cdx2 expression diminished phosphorylated Abl and phosphorylated Rac levels, which are downstream effectors of RTKs. Specific chemical inhibition or short interfering RNA (shRNA) knockdown of c-Abl kinase phenocopied Cdx2's cell-cell adhesion effects. In Colo 205 cells, Cdx2 reduced PDGF receptor and IGF-I receptor activation. This was mediated by caveolin-1, which was induced by Cdx2. Targeted shRNA knockdown of caveolin-1 restored PDGF receptor and reversed E-cadherin membrane trafficking, despite Cdx2 expression. We conclude that Cdx2 regulates E-cadherin function indirectly by disrupting RTK activity and enhancing E-cadherin trafficking to the cell membrane compartment. This novel mechanism advances Cdx2's prodifferentiation and antitumor properties and suggests that Cdx2 may broadly regulate RTK activity in normal intestinal epithelium by modulating membrane trafficking of proteins.
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Affiliation(s)
- Shinsuke Funakoshi
- 1Division of Gastroenterology, Department of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania;
| | - Jianping Kong
- 1Division of Gastroenterology, Department of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania;
| | - Mary Ann Crissey
- 1Division of Gastroenterology, Department of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania;
| | - Long Dang
- 2Division of Hematology/Oncology, Department of Internal Medicine, University of Florida, Gainesville, Florida; and
| | - Duyen Dang
- 3Division of Gastroenterology, Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan
| | - John P. Lynch
- 1Division of Gastroenterology, Department of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania;
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Rao JN, Rathor N, Zou T, Liu L, Xiao L, Yu TX, Cui YH, Wang JY. STIM1 translocation to the plasma membrane enhances intestinal epithelial restitution by inducing TRPC1-mediated Ca2+ signaling after wounding. Am J Physiol Cell Physiol 2010; 299:C579-88. [PMID: 20631248 PMCID: PMC2944314 DOI: 10.1152/ajpcell.00066.2010] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2010] [Accepted: 06/11/2010] [Indexed: 11/22/2022]
Abstract
Early epithelial restitution is an important repair modality in the gut mucosa and occurs as a consequence of epithelial cell migration. Canonical transient receptor potential-1 (TRPC1) functions as a store-operated Ca2+ channel (SOCs) in intestinal epithelial cells (IECs) and regulates intestinal restitution, but the exact upstream signals initiating TRPC1 activation after mucosal injury remain elusive. Stromal interaction molecule 1 (STIM1) is a single membrane-spanning protein and is recently identified as essential components of SOC activation. The current study was performed to determine whether STIM1 plays a role in the regulation of intestinal epithelial restitution by activating TRPC1 channels. STIM1 translocation to the plasma membrane increased after wounding, which was followed by an increase in IEC migration to reseal wounds. Increased STIM1 levels at the plasma membrane by overexpressing EF-hand mutant STIM1 enhanced Ca2+ influx through SOCs and stimulated IEC migration after wounding. STIM1 interacted with TRPC1 and formed STIM1/TRPC1 complex, whereas inactivation of STIM1 by STIM1 silencing decreased SOC-mediated Ca2+ influx and inhibited epithelial restitution. In cells overexpressing EF-hand mutant STIM1, TRPC1 silencing also decreased STIM1/TRPC1 complex, reduced SOC-mediated Ca2+ influx, and repressed cell migration after wounding. Our findings demonstrate that induced STIM1 translocation to the plasma membrane promotes IEC migration after wounding by enhancing TRPC1-mediated Ca2+ signaling and provide new insight into the mechanism of intestinal epithelial restitution.
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Affiliation(s)
- Jaladanki N Rao
- Cell Biology Group, Department of Surgery, University of Maryland School of Medicine, Baltimore, Maryland, USA
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72
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Gong L, Debruyne PR, Witek M, Nielsen K, Snook A, Lin JE, Bombonati A, Palazzo J, Schulz S, Waldman SA. Bile acids initiate lineage-addicted gastroesophageal tumorigenesis by suppressing the EGF receptor-AKT axis. Clin Transl Sci 2010; 2:286-93. [PMID: 20443907 PMCID: PMC5407481 DOI: 10.1111/j.1752-8062.2009.00131.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
While bile acids are a risk factor for tumorigenesis induced by reflux disease, the mechanisms by which they contribute to neoplasia remain undefined. Here, we reveal that in gastroesophageal junction (GEJ) cells bile acids activate a tissue-specific developmental program defining the intestinal epithelial cell phenotype characterizing GEJ metaplasia. Deoxycholic acid (DCA) inhibited phosphorylation of EGF receptors (EGFRs) suppressing the proto-oncogene AKT. Suppression of EGFRs and AKT by DCA actuated an intestine-specific cascade in which NF-kappaB transactivated the tissue-specific transcription factor CDX2. In turn, CDX2 orchestrated a lineage-specific differentiation program encompassing genes characterizing intestinal epithelial cells. Conversely, progression from metaplasia to invasive carcinoma in patients, universally associated with autonomous activation of EGFRs and/or AKT, was coupled with loss of this intestinal program. Thus, bile acids induce intestinal metaplasia at the GEJ by activating the lineage-specific differentiation program involving suppression of EGFR and AKT, activating the NF-kappaB-CDX2 axis. Induction of this axis provides the context for lineage-addicted tumorigenesis, in which autonomous activation of AKT corrupts adaptive intestinal NF-kappaB signaling, amplifying tumorigenic programs.
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Affiliation(s)
- Li Gong
- Department of Pharmacology and Experimental Therapeutics, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
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73
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74
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Weimann A, Zimmermann M, Gross M, Slevogt H, Rieger A, Morawietz L. CDX2 and LI-cadherin expression in esophageal mucosa: use of both markers can facilitate the histologic diagnosis of Barrett's esophagus and carcinoma. Int J Surg Pathol 2010; 18:330-7. [PMID: 20444732 DOI: 10.1177/1066896910364228] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
BACKGROUND Barrett's mucosa is a risk factor for esophageal adenocarcinoma and should be detected at an early stage. CDX2 and liver-intestine (LI)-cadherin are intestine-specific markers. Aberrant CDX2 expression has been demonstrated in Barrett's metaplasia, esophagitis, and intestinal metaplasia of the stomach. METHODS The relationship between CDX2 and LI-cadherin expression was investigated in normal gastroesophageal (n = 24) and in Barrett's (n = 20) mucosa, in low-grade (n = 15) and high-grade (n = 13) intraepithelial neoplasia (IEN) as well as in esophageal adenocarcinoma (n = 16), using immunohistochemistry. RESULTS Nuclear positivity for CDX2 coupled with membranous expression of LI-cadherin was observed in about 70% of the epithelial cells of Barrett's mucosa. The intensity of staining and the percentage of positive cells increased within the sequential steps of low-grade to high-grade IEN, whereas the normal cylindric epithelium lacked the expression of both. In adenocarcinoma, the expression of LI-cadherin and CDX2 was significantly weaker or absent. CONCLUSIONS CDX2 and LI-cadherin are sensitive markers of intestinal metaplasia with or without dysplasia in the upper gastrointestinal tract. Both can be helpful for the early histologic diagnosis of Barrett's esophagus and its subsequent lesions; however, they do not significantly discern between different grades of dysplasia.
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75
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Kir G, Gurbuz A, Karateke A, Kir M. Clinicopathologic and immunohistochemical profile of ovarian metastases from colorectal carcinoma. World J Gastrointest Surg 2010; 2:109-16. [PMID: 21160859 PMCID: PMC2999225 DOI: 10.4240/wjgs.v2.i4.109] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/22/2009] [Revised: 01/28/2010] [Accepted: 02/04/2010] [Indexed: 02/06/2023] Open
Abstract
Metastasis of colorectal adenocarcinoma of the ovary is not an uncommon occurrence and ovarian metastases from colorectal carcinoma frequently mimic endometrioid and mucinous primary ovarian carcinoma. The clinical and pathologic features of metastatic colorectal adenocarcinoma involving the ovary is reviewed with particular focus on the diagnostic challenge of distinguishing these secondary ovarian tumors from primary ovarian neoplasm. Immunohistochemical stains that may be useful in the differential diagnosis of metastatic colorectal tumors to the ovary and primary ovarian tumors are detailed.
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Affiliation(s)
- Gozde Kir
- Gozde Kir, Department of Pathology, Umraniye Education and Research Hospital, Umraniye, Istanbul 34766, Turkey
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76
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Abstract
Barrett's oesophagus is the replacement of normal squamous oesophageal epithelium with an intestinalized columnar epithelium. Although some insight has been gained as to what Barrett's oesophagus is, how this columnar epithelium emerges from within a stratified squamous epithelium remains an unanswered question. We have sought to determine whether oesophageal keratinocytes can be trans-differentiated into Barrett's oesophagus cells. Using an Affymetrix microarray, we found unexpectedly that gene-expression patterns in the Barrett's oesophagus were only slightly more similar to the normal small intestine than they were to the normal oesophagus. Thus gene-expression patterns suggest significant molecular similarities remain between Barrett's oesophagus cells and normal squamous oesophageal epithelium, despite their histological resemblance with intestine. We next determined whether directed expression of intestine-specific transcription factors could induce intestinalization of keratinocytes. Retroviral-mediated Cdx2 (Caudal-type homeobox 2) expression in immortalized human oesophageal keratinocytes engineered with human telomerase reverse transcriptase (EPC2-hTERT cells) could be established transiently, but not maintained, and was associated with a reduction in cell proliferation. Co-expression of cyclin D1 rescued proliferation in the Cdx2-expressing cells, but co-expression of dominant-negative p53 did not. Cdx2 expression in the EPC2-hTERT.D1 cells did not induce intestinalization. However, when combined with treatments that induce chromatin remodelling, there was a significant induction of Barrett's oesophagus-associated genes. Studies are ongoing to determine whether other intestinal transcription factors, either alone or in combination, can provoke greater intestinalization of oesophageal keratinocytes. We conclude that, on the basis of gene-expression patterns, Barrett's oesophagus epithelial cells may represent an intermediate between oesophageal keratinocytes and intestinal epithelial cells. Moreover, our findings suggest that it may be possible to induce Barrett's oesophagus epithelial cells from oesophageal keratinocytes by altering the expression of certain critical genes.
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77
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Peters JH, Avisar N. The molecular pathogenesis of Barrett's esophagus: common signaling pathways in embryogenesis metaplasia and neoplasia. J Gastrointest Surg 2010; 14 Suppl 1:S81-7. [PMID: 19760304 DOI: 10.1007/s11605-009-1011-7] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/18/2009] [Accepted: 08/25/2009] [Indexed: 01/31/2023]
Abstract
Although Barrett's esophagus has been recognized for over 50 years, the cellular and molecular mechanisms leading to the replacement of squamous esophageal epithelium with a columnar type are largely unknown. Barrett's is known to be an acquired process secondary to chronic gastroesophageal reflux disease and occurs in the presence of severe disruption of the gastroesophageal barrier and reflux of a mixture of gastric and duodenal content. Current hypothesis suggest that epithelial change occurs due to stimulation of esophageal stem cells present in the basal layers of the epithelium or submucosal glands, toward a columnar epithelial differentiation pathway. The transcription factor CDX2 seems to play a key role in promoting the cellular biology necessary for columnar differentiation, and can be induced by bile salt and acid stimulation. Several cellular signaling pathways responsible for modulation of intestinal differentiation have also been identified and include WNT, Notch, BMP, Sonic HH and TGFB. These also have been shown to respond to stimulation by bile acids, acid or both and may influence CDX2 expression. Their relative activity within the stem cell population is almost certainly responsible for the development of the esophageal columnar epithelial phenotype we know as Barrett's esophagus.
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Affiliation(s)
- Jeffrey H Peters
- Department of Surgery, University of Rochester, Rochester, NY 14642, USA.
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78
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Stairs DB, Kong J, Lynch JP. Cdx genes, inflammation, and the pathogenesis of intestinal metaplasia. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2010; 96:231-70. [PMID: 21075347 PMCID: PMC6005371 DOI: 10.1016/b978-0-12-381280-3.00010-5] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Intestinal metaplasia (IM) is a biologically interesting and clinically relevant condition in which one differentiated type of epithelium is replaced by another that is morphologically similar to normal intestinal epithelium. Two classic examples of this are gastric IM and Barrett's esophagus (BE). In both, a chronic inflammatory microenvironment, provoked either by Helicobacter pylori infection of the stomach or acid and bile reflux into the esophagus, precedes the metaplasia. The Caudal-related homeodomain transcription factors Cdx1 and Cdx2 are critical regulators of the normal intestinal epithelial cell phenotype. Ectopic expression of Cdx1 and Cdx2 occurs in both gastric IM as well as in BE. This expression precedes the onset of the metaplasia and implies a causal role for these factors in this process. We review the observations regarding the role of chronic inflammation and the Cdx transcription factors in the pathogenesis of gastric IM and BE.
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Affiliation(s)
- Douglas B Stairs
- Department of Medicine, Division of Gastroenterology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
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79
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Wu Y, Li ZW, Li JY. Phenotypic classification of well-differentiated gastric adenocarcinoma. Chin J Cancer Res 2009. [DOI: 10.1007/s11670-009-0278-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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80
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Boyd M, Bressendorff S, Møller J, Olsen J, Troelsen JT. Mapping of HNF4alpha target genes in intestinal epithelial cells. BMC Gastroenterol 2009; 9:68. [PMID: 19761587 PMCID: PMC2761415 DOI: 10.1186/1471-230x-9-68] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2009] [Accepted: 09/17/2009] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND The role of HNF4alpha has been extensively studied in hepatocytes and pancreatic beta-cells, and HNF4alpha is also regarded as a key regulator of intestinal epithelial cell differentiation. The aim of the present work is to identify novel HNF4alpha target genes in the human intestinal epithelial cells in order to elucidate the role of HNF4alpha in the intestinal differentiation progress. METHODS We have performed a ChIP-chip analysis of the human intestinal cell line Caco-2 in order to make a genome-wide identification of HNF4alpha binding to promoter regions. The HNF4alpha ChIP-chip data was matched with gene expression and histone H3 acetylation status of the promoters in order to identify HNF4alpha binding to actively transcribed genes with an open chromatin structure. RESULTS 1,541 genes were identified as potential HNF4alpha targets, many of which have not previously been described as being regulated by HNF4alpha. The 1,541 genes contributed significantly to gene ontology (GO) pathways categorized by lipid and amino acid transport and metabolism. An analysis of the homeodomain transcription factor Cdx-2 (CDX2), the disaccharidase trehalase (TREH), and the tight junction protein cingulin (CGN) promoters verified that these genes are bound by HNF4alpha in Caco2 cells. For the Cdx-2 and trehalase promoters the HNF4alpha binding was verified in mouse small intestine epithelium. CONCLUSION The HNF4alpha regulation of the Cdx-2 promoter unravels a transcription factor network also including HNF1alpha, all of which are transcription factors involved in intestinal development and gene expression.
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Affiliation(s)
- Mette Boyd
- Department of Cellular and Molecular Medicine, Panum Institute, Building 6,4, University of Copenhagen, Blegdamsvej 3B 2200 Copenhagen N, Denmark.
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81
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Guo RJ, Funakoshi S, Lee HH, Kong J, Lynch JP. The intestine-specific transcription factor Cdx2 inhibits beta-catenin/TCF transcriptional activity by disrupting the beta-catenin-TCF protein complex. Carcinogenesis 2009; 31:159-66. [PMID: 19734199 DOI: 10.1093/carcin/bgp213] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Cdx2 is an intestine-specific transcription factor known to regulate proliferation and differentiation. We have reported previously that Cdx2 limits the proliferation of human colon cancer cells by inhibiting the transcriptional activity of the beta-catenin-T-cell factor (TCF) bipartite complex. Herein we further elucidate this mechanism. Studies with a classic Cdx2 target gene and a canonical Wnt/beta-catenin/TCF reporter suggest that Cdx2 regulates these promoters by distinctly different processes. Specifically, inhibition of beta-catenin/TCF activity by Cdx2 does not require Cdx2 transcriptional activity. Instead, Cdx2 binds beta-catenin and disrupts its interaction with the DNA-binding TCF factors, thereby silencing beta-catenin/TCF target gene expression. Using Cdx2 mutants, we map the Cdx2 domains required for the inhibition of beta-catenin/TCF activity. We identify a subdomain in the N-terminus that is highly conserved and when mutated significantly reduces Cdx2 inhibition of beta-catenin/TCF transcriptional activity. Mutation of this subdomain also abrogates Cdx2's anti-proliferative effects in colon cancer cells. In summary, we conclude that Cdx2 binds beta-catenin and disrupts the beta-catenin-TCF complex. Considering the pivotal role of beta-catenin/TCF activity in driving proliferation of normal intestinal epithelial and colon cancer cells, our findings suggest a novel mechanism for Cdx2-mediated regulation of Wnt/beta-catenin signaling and cell proliferation.
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Affiliation(s)
- Rong-Jun Guo
- Division of Gastroenterology, Department of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
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Liu ZL, Moon J. A novel NADPH-dependent aldehyde reductase gene from Saccharomyces cerevisiae NRRL Y-12632 involved in the detoxification of aldehyde inhibitors derived from lignocellulosic biomass conversion. Gene 2009; 446:1-10. [PMID: 19577617 DOI: 10.1016/j.gene.2009.06.018] [Citation(s) in RCA: 98] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2009] [Revised: 06/16/2009] [Accepted: 06/19/2009] [Indexed: 10/20/2022]
Abstract
Aldehyde inhibitors such as furfural, 5-hydroxymethylfurfural, anisaldehyde, benzaldehyde, cinnamaldehyde, and phenylaldehyde are commonly generated during lignocellulosic biomass conversion process for low-cost cellulosic ethanol production that interferes with subsequent microbial growth and fermentation. In situ detoxification of the aldehyde inhibitors is possible by the tolerant ethanologenic yeast that involves multiple genes including numerous functional reductases. In this study, we report a novel aldehyde reductase gene clone Y63 from ethanologenic yeast Saccharomyces cerevisiae NRRL Y12632, representing the uncharacterized ORF YGL157W, which demonstrated NADPH-dependent reduction activities toward at least 14 aldehyde substrates. The identity of gene clone Y63 is the same with YGL157W of SGD since a variation of only 35 nucleotides in genomic sequence and three amino acid residues were observed between the two that share the same length of 347 residues in size. As one among the highly induced genes, YGL157W of Y-12632 showed significantly high levels of transcript abundance in response to furfural and HMF challenges. Based on the deduced amino acid sequence and the most conserved functional motif analyses including closely related reductases from five other yeast species to this date, YGL157W was identified as a member of the subclass 'intermediate' of the SDR (short-chain dehydrogenase/reductase) superfamily with the following typical characteristics: the most conserved catalytic site to lie at Tyr(169)-X-X-X-Lys(173); an indispensable reduction catalytic triad at Ser(131), Tyr(169), and Lys(173), and an approved cofactor-binding motif at Gly(11)-X-X-Gly(14)-X-X-Ala(17) near the N-terminus. YGL039W, YDR541C, and YOL151W (GRE2) appeared to be the similar type of enzymes falling into the same category of the intermediate subfamily.
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Affiliation(s)
- Z Lewis Liu
- U.S. Department of Agriculture, Agricultural Research Service, National Center for Agricultural Utilization Research, 1815 N University St., Peoria, IL 61604, USA.
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83
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Chang DF, Tsai SC, Wang XC, Xia P, Senadheera D, Lutzko C. Molecular characterization of the human NANOG protein. Stem Cells 2009; 27:812-21. [PMID: 19350681 DOI: 10.1634/stemcells.2008-0657] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
NANOG is a key transcriptional regulator of pluripotent stem cell (PSC) self-renewal. NANOG occupies promoters that are active and others that are repressed during self-renewal; however, the mechanisms by which NANOG regulates transcriptional repression and activation are unknown. We hypothesized that individual protein domains of NANOG control its interactions with both the promoters and its coregulators. We performed a detailed characterization of the functional domains in the human (h) NANOG protein, using a panel of deletion-mutant and point-mutant constructs. We determined that six amino acids in the homeodomain ((136)YKQVKT(141)) are sufficient for the nuclear localization of hNANOG. We also determined that the tryptophan-rich region (W) of hNANOG contains a CRM1-independent signal for nuclear export, suggesting a possible cellular shuttling behavior that has not been reported for hNANOG. We also show that at least four tryptophans are required for nuclear export. We also determined that similar to murine (m) NANOG, the W region of hNANOG contains a homodimerization domain. Finally, in vitro transactivation analyses identified distinct regions that enhance or diminish activity at gene promoters that are active during self-renewal. Specifically, the N-terminal region interferes with transcription and removal of this region that produced a "super-active" hNANOG with enhanced transcriptional activity. We also confirmed that the transcriptional activator in hNANOG is contained in the C-terminal region, similar to murine NANOG. In summary, this study has characterized the structure and function of hNANOG protein leading to an increased understanding of the mechanism by which hNANOG regulates both transcriptional activation and repression during PSC self-renewal.
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Affiliation(s)
- David F Chang
- Department of Pediatrics, Division of Research Immunology/Bone Marrow Transplantation, Saban Research Institute at Childrens Hospital Los Angles, University of Southern California, Los Angeles, California, USA
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84
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Gennari L, Merlotti D, De Paola V, Martini G, Nuti R. Update on the pharmacogenetics of the vitamin D receptor and osteoporosis. Pharmacogenomics 2009; 10:417-33. [PMID: 19290791 DOI: 10.2217/14622416.10.3.417] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Vitamin D and calcium are essential for normal skeletal growth and for maintaining the mechanical and structural integrity of the skeleton. Reduced intake of calcium and vitamin D may be associated with reduced bone mass and osteoporosis while a chronic and severe vitamin D deficiency may lead to osteomalacia. Given the importance of vitamin D in bone homeostasis, common polymorphisms in the vitamin D receptor gene were the first to be investigated as possible determinants of bone mass and fracture risk. Even though results are still conflicting and the molecular mechanisms by which these polymorphisms influence receptor activity remain in part to be investigated, an additional important issue is represented by their potential pharmacogenomic and pharmacogenetic implications. This review analyzes major pharmacogenetic studies of polymorphisms in the vitamin D receptor gene and osteoporosis.
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Affiliation(s)
- Luigi Gennari
- Department of Internal Medicine, Endocrine-Metabolic Sciences & Biochemistry, University of Siena, Viale Bracci 1, 53100 Siena, Italy.
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85
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Yamaguchi N, Miyamoto S, Ogura Y, Goda T, Suruga K. Hepatocyte nuclear factor-4alpha regulates human cellular retinol-binding protein type II gene expression in intestinal cells. Am J Physiol Gastrointest Liver Physiol 2009; 296:G524-33. [PMID: 19147806 DOI: 10.1152/ajpgi.90469.2008] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Cellular retinol-binding protein type II (CRBPII) is abundantly expressed in the small intestinal enterocytes of many vertebrates and plays important physiological roles in intestinal absorption, transport, and metabolism of vitamin A. In the present study, we investigated regulation of human CRBPII gene expression using human intestinal Caco-2 BBe cells. We found that the human CRBPII gene contained a direct repeat 1 (DR-1)-like nuclear receptor response element in the proximal promoter region and that endogenous hepatocyte nuclear factor-4alpha (HNF-4alpha) was a major transcription factor binding to the DR-1-like element. Cotransfection of HNF-4alpha expression vector transactivated the human CRBPII gene promoter activity, whereas mutation of the DR-1-like element abolished the promoter activity. Stably transfected Caco-2 BBe cells overexpressing HNF-4alpha significantly increased endogenous CRBPII gene expression and retinyl ester synthesis. Reduction of HNF-4alpha protein levels by HNF-4alpha small interference RNA decreased CRBPII gene expression. Caco-2 BBe cells treated with phorbol 12-myristate 13-acetate, a protein kinase C activator, decreased nuclear HNF-4alpha protein level and binding activity to the human CRBPII gene DR-1-like element, as well as CRBPII gene expression. Moreover, nuclear HNF-4alpha protein levels, HNF-4alpha protein binding to human CRBPII DR-1-like elements, and CRBPII gene expression level were coordinately increased during Caco-2 BBe cell differentiation. These results suggest that HNF-4alpha is an important transcriptional factor that regulates human CRBPII gene expression and provide the possibility for a novel function of HNF-4alpha in the regulation of human intestinal vitamin A absorption and metabolism.
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Affiliation(s)
- Noriaki Yamaguchi
- Graduate School of Human Health Sciences, University of Nagasaki, 1-1-1 Manabino, Nagayo-cho, Nishisonogi-gun, Nagasaki 851-2195, Japan
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86
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Yamamichi N, Inada KI, Furukawa C, Sakurai K, Tando T, Ishizaka A, Haraguchi T, Mizutani T, Fujishiro M, Shimomura R, Oka M, Ichinose M, Tsutsumi Y, Omata M, Iba H. Cdx2 and the Brm-type SWI/SNF complex cooperatively regulate villin expression in gastrointestinal cells. Exp Cell Res 2009; 315:1779-89. [PMID: 19371634 DOI: 10.1016/j.yexcr.2009.01.006] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2008] [Revised: 01/14/2009] [Accepted: 01/14/2009] [Indexed: 01/07/2023]
Abstract
In our recent study showing a correlation between Brm-deficiency and undifferentiated status of gastric cancer, we found that the Brm-type SWI/SNF complex is required for villin expression. To elucidate intestinal villin regulation more precisely, we here analyzed structure and function of the promoter of human villin. About 1.1 kb upstream of the determined major transcription start site, we identified a highly conserved region (HCR-Cdx) among mammals, which contains two binding sites for Cdx. Expression analyses of 30 human gastrointestinal cell lines suggested that villin is regulated by Cdx2. Introduction of Cdx family genes into colorectal SW480 cells revealed that villin is strongly induced strongly by Cdx2, moderately by Cdx1, and marginally by Cdx4. Knockdown of Cdx2 in SW480 cells caused a clear downregulation of villin, and reporter assays showed that HCR-Cdx is crucial for Cdx2-dependent and Brm-dependent villin expression. Immunohistochemical analyses of gastric intestinal metaplasia and cancer revealed that villin and Cdx2 expression are tightly coupled. GST pull-down assays demonstrated a direct interaction between Cdx2 and several SWI/SNF subunits. Chromatin immunoprecipitation analyses showed the recruitment of Cdx2 and Brm around HCR-Cdx. From these results, we concluded that Cdx2 regulates intestinal villin expression through recruiting Brm-type SWI/SNF complex to the villin promoter.
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Affiliation(s)
- Nobutake Yamamichi
- Department of Microbiology and Immunology, Division of Host-Parasite Interaction, Institute of Medical Science, University of Tokyo, Shirokanedai Minato-ku, Tokyo Japan
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87
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Saksena S, Dwivedi A, Singla A, Gill RK, Tyagi S, Borthakur A, Alrefai WA, Ramaswamy K, Dudeja PK. Characterization of the 5'-flanking region and regulation of expression of human anion exchanger SLC26A6. J Cell Biochem 2009; 105:454-66. [PMID: 18655181 DOI: 10.1002/jcb.21842] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
SLC26A6 (putative anion transporter 1, PAT1) has been shown to play an important role in mediating the luminal Cl(-)/OH(-)(HCO(3)(-)) exchange process in the intestine. Very little is known about the molecular mechanisms involved in the transcriptional regulation of intestinal SLC26A6 gene expression in the intestine. Current studies were, therefore, designed to clone and characterize the 5'-regulatory region of the human SLC26A6 gene and determine the mechanisms involved in its regulation. A 1,120 bp (p-964/+156) SLC26A6 promoter fragment cloned upstream to the luciferase reporter gene in pGL2-basic exhibited high promoter activity when transfected in Caco2 cells. Progressive deletions of the 5'-flanking region demonstrated that -214/-44 region of the promoter harbors cis-acting elements important for maximal SLC26A6 promoter activity. Since, diarrhea associated with inflammatory bowel diseases is attributed to increased secretion of pro-inflammatory cytokines, we examined the effects of IFNgamma (30 ng/ml, 24 h) on SLC26A6 function, expression and promoter activity. IFNgamma decreased both SLC26A6 mRNA and function and repressed SLC26A6 promoter activity. Deletion analysis indicated that IFNgamma response element is located between -414/-214 region and sequence analysis of this region revealed the presence of potential Interferon Stimulated Responsive Element (ISRE), a binding site (-318/-300 bp) for interferon regulatory factor-1 transcription factor (IRF-1). Mutations in the potential ISRE site abrogated the inhibitory effects of IFNgamma. These studies provided novel evidence for the involvement of IRF-1 in the regulation of SLC26A6 gene expression by IFNgamma in the human intestine.
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Affiliation(s)
- Seema Saksena
- Department of Medicine, University of Illinois at Chicago, Jesse Brown VA Medical Center, Chicago, Illinois 60612, USA.
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88
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Fukushima A, Aizaki Y, Sakuma K. Short-chain fatty acids induce intestinal transient receptor potential vanilloid type 6 expression in rats and Caco-2 cells. J Nutr 2009; 139:20-5. [PMID: 19056662 DOI: 10.3945/jn.108.096230] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Fructooligosaccharides (FOS) are indigestible oligosaccharides that increase calcium absorption by the colorectum in rats, but the underlying mechanisms remain unclear. We therefore investigated the effects of FOS on expressions of genes involved with calcium absorption in rat colorectal mucosa cells. After feeding a diet containing FOS (100 g/kg diet) to rats for 2 d, we investigated gene transcripts of transient receptor potential vanilloid type 6 (TRPV6), calbindin-D9k, and plasma membrane calcium-ATPase 1b (PMCA1b). The FOS diet increased expression of TRPV6 and calbindin-D9k but did not affect PMCA1b expression. Because FOS could not directly affect gene expression, SCFA formed as fermentation products of FOS were considered as likely intermediates. SCFA (2.0 mmol/L) were thus added to Caco-2 human colonic epithelial cells, resulting in significantly increased mRNA expression of TRPV6. To ascertain the effects of SCFA on mRNA expression, a genomic clone of TRPV6 was isolated. Using luciferase reporter assay, a segment between -71 nucleotides and the translation start site was found to contain a positive responsive element to SCFA. These results suggest that FOS increase calcium absorption by increasing mRNA expression of TRPV6 in rat colorectum, and cell culture analysis indicated that SCFA, as fermentation products of FOS, are involved in the increased mRNA expression of TRPV6. We found for the first time, to our knowledge, that regulation of TRPV6 gene expression by SCFA may be a molecular mechanism involved in the promotion of calcium absorption by FOS in rats.
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Affiliation(s)
- Akiko Fukushima
- Department of Molecular Nutrition, Kagawa Nutrition University, 3-9-21 Chiyoda, Sakado, Saitama 350-0288, Japan
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89
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Comprehensive evaluation of CDX2 in invasive cervical adenocarcinomas: immunopositivity in the absence of overt colorectal morphology. Am J Surg Pathol 2008; 32:1608-12. [PMID: 18753946 DOI: 10.1097/pas.0b013e31816d71c4] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
CDX2 is a member of the caudal-related homeobox gene family that is expressed during the normal development of the intestinal tract. In addition to staining adenocarcinomas of the alimentary system, studies have demonstrated CDX2 positivity in a percentage of ovarian mucinous and endometrioid tumors, carcinoids, and some adenocarcinomas of other sites such as the urinary bladder, prostate, lung, and pancreas. However, CDX2 immunostaining in cervical adenocarcinomas has not been examined in detail with comparison to important clinicopathologic characteristics including histopathologic subtype, tumor stage, and patient follow-up. In this study of 81 invasive cervical adenocarcinomas, 24 of the cases (30%) demonstrated nuclear positivity. Ten of the 15 (67%) endometrioid tumors had positive nuclear staining, compared with 7 of the 33 (21%) endocervical "usual-type" carcinomas, and 7 of the 33 (21%) remaining subtypes (adenosquamous, glassy cell, clear cell, serous, villoglandular, enteric). The frequency of nuclear staining for the endometrioid subtype was significantly different compared with that for the endocervical and other subtypes (P=0.003). Some cases showed granular cytoplasmic staining with or without corresponding nuclear positivity. Positive nuclear or cytoplasmic staining for CDX2 did not correlate with disease stage or patient outcome. Our results indicate that cervical adenocarcinomas can show nuclear immunopositivity for CDX2 even in the absence of overt morphologic features of colorectal differentiation. The frequency and pattern of CDX2 staining in the more common histologic subtypes of cervical adenocarcinoma (endocervical usual-type and endometrioid) is parallel to that which is seen for adenocarcinomas of the upper gastrointestinal tract and pancreaticobiliary system.
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90
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Wani Y, Notohara K, Fujisawa M. Aberrant expression of an "intestinal marker" Cdx2 in pyloric gland adenoma of the gallbladder. Virchows Arch 2008; 453:521-7. [PMID: 18843504 DOI: 10.1007/s00428-008-0680-z] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2008] [Revised: 09/08/2008] [Accepted: 09/23/2008] [Indexed: 12/12/2022]
Abstract
The aim of this study was to survey Cdx2 expression in pyloric gland adenoma (PGA) of the gallbladder. We reviewed 29 PGA cases, ten (34.4%) and seven (24.1%) of which showed intestinal metaplasia (IM) and squamous morule (SM), respectively. The immunostaining for Cdx2, beta-catenin, MUC5AC, MUC2, MUC6, and M-GGMC-1 was performed and scored (0 = negative, 1+ = <10%, 2+ = 10% to <30%, 3+ = 30% to <50%, 4+ = 50% to <70%, 5+ = 70-100%). Although its scores were relatively low (1+ or 2+), Cdx2 was frequently expressed in 27 cases (93.1%). Not only goblet and/or Paneth cells were positive but also non-IM cells in PGAs, as opposed to the lack of staining in the background mucosa. Cdx2 scores were not correlated with those of IM (p = 0.485) and MUC2 (p = 0.868). Of note, Cdx2 was positive in foci of SM in all seven cases, and there was a significant difference in Cdx2 scores between PGAs with and without SM. Furthermore, the p value of scores between Cdx2 and beta-catenin was 0.051, and both mean labeling indices (LIs) were correlated (r = 0.736). With Cdx2, higher morular LIs than glandular LIs were observed (p = 0.001). Finally, we concluded that aberrant Cdx2 expression in PGAs is closely associated with nuclear beta-catenin expression and SM in contrast with IM.
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Affiliation(s)
- Yoji Wani
- Department of Pathology, Kurashiki Central Hospital, Kurashiki, Okayama, Japan.
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91
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Function of reactive oxygen species during animal development: Passive or active? Dev Biol 2008; 320:1-11. [DOI: 10.1016/j.ydbio.2008.04.041] [Citation(s) in RCA: 262] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2007] [Revised: 04/25/2008] [Accepted: 04/30/2008] [Indexed: 02/07/2023]
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92
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Houghton O, Connolly LE, McCluggage WG. Morules in endometrioid proliferations of the uterus and ovary consistently express the intestinal transcription factor CDX2. Histopathology 2008; 53:156-65. [DOI: 10.1111/j.1365-2559.2008.03083.x] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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93
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Yu SL, Singh S, Chen HW, Chen HY, Chen JJW, Chen WJ, Chen HS, Chen SC. Intra-abdominal adhesion formation induces anti-oxidative injury, enhances cell proliferation, and prevents complement-mediated lysis. Wound Repair Regen 2008; 16:388-98. [PMID: 18471257 DOI: 10.1111/j.1524-475x.2008.00378.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Whether the alteration of gene expression is accompanied with intra-abdominal adhesion formation is unclear. The aim of this study was to analyze the dynamic gene expression patterns in an animal model of intra-abdominal adhesion formation. The mRNA was extracted from the jejunums of sham control mice and jejunum-abrading mice at 1, 3, 7, and 14 days postsurgery. The mouse cDNA microarray was used to monitor the dynamic changes of the tested genes and up-regulated and down-regulated genes were calculated. Quantitative real-time RT-PCR, and immunohistochemistry staining were used to confirm the accuracy of microarray results at RNA and protein levels. The top 100 genes with the greatest change across all studied mice groups were identified and 93 of them were correct after sequencing verification. Of the 93 genes, 74 genes were up-regulated and 19 were down-regulated following jejunal abrasion. Gene expressions of complement-mediated lysis, anti-oxidative response, and cell proliferation were significantly induced during adhesion formation. Intra-abdominal adhesion induces several genes to eliminate overfilled complement-mediated lysis, prevent oxidative injuries, and enhance cell proliferation. These findings may provide insights into the pathogenesis of intra-abdominal adhesion formation and might also help to identify some new target genes for specific diagnostic tools and novel therapeutic strategies.
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Affiliation(s)
- Sung-Liang Yu
- Department of Clinical Laboratory Sciences and Medical Biotechnology, National Taiwan University College of Medicine, Taipei, Taiwan
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94
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Gutiérrez-González L, Wright NA. Biology of intestinal metaplasia in 2008: more than a simple phenotypic alteration. Dig Liver Dis 2008; 40:510-22. [PMID: 18400571 DOI: 10.1016/j.dld.2008.02.029] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2008] [Accepted: 02/18/2008] [Indexed: 12/11/2022]
Abstract
This review concentrates on one main aspect of cancerization in the oesophagus and stomach: principally, intestinal metaplasia. There are at least two other important pathways that lead to cancer and do not need such a morphological transformation. One is the gastric type of carcinoma on the Lauren classification, which arises directly from the stem cell zone and is the signet ring form of cancer, while the other is spasmolytic polypeptide-expressing metaplasia (SPEM)--spasmolytic polypeptide (TFF2) expressing metaplasia, where the gastric glands become filled with TFF2-expressing cells and may also lead to gastric dysplasia and cancer. The development of intestinal metaplasia is complex. Here, we examine intestinal metaplasia in molecular terms, noting the over-expression of Cdx1, Cdx2, Pdx1, Oct1, TFF3 and the downregulation of Hedgehog signalling; Runx3 is deactivated by epigenetic silencing, and pathways such as Wnt and MARK/ERK are involved. These changes start to explain the principles of the development of intestinal metaplasia and suggest that the regulation of these genes is of importance in the development of gastric cancer.
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95
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van Baal JWPM, Bozikas A, Pronk R, Ten Kate FJW, Milano F, Rygiel AM, Rosmolen WD, Peppelenbosch MP, Bergman JJGHM, Krishnadath KK. Cytokeratin and CDX-2 expression in Barrett's esophagus. Scand J Gastroenterol 2008; 43:132-40. [PMID: 18224560 DOI: 10.1080/00365520701676575] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
OBJECTIVE Barrett's esophagus (BE) is a premalignant condition of the distal esophagus. For diagnostic purposes it is important to find biomarkers that can specifically identify BE, for instance to differentiate BE epithelial cells from gastric cardia epithelial cells in brush cytology specimens. The objective of this study was to determine the specificity of CDX-2 and a set of cytokeratins (CKs) as specific markers for BE as compared with normal squamous esophageal and gastric cardia tissue. MATERIAL AND METHODS Immunohistochemistry (IHC) with specific antibodies against CDX-2, and a set of CKs was performed on fresh frozen consecutive tissue sections of normal squamous, gastric cardia and non-dysplastic BE of 80 patients. RESULTS IHC results showed CK8, CK18 and CK20 expression in both BE and gastric cardia, while CK7 was seen in all BE but also in 26% of gastric cardia biopsies. CK10/13 was only expressed in normal squamous epithelium. CDX-2 nuclear staining was found in 87.5% of the BE biopsies, whereas normal squamous esophagus and cardia biopsies were negative. CONCLUSIONS CDX-2 in combination with a set of CKs can be used as biomarkers to distinguish between BE and normal squamous esophagus. In order to distinguish BE from cardia tissue, a combination of CDX-2 and CK7 is most informative.
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Affiliation(s)
- Jantine W P M van Baal
- Center for Experimental Molecular Medicine in Amsterdam, University Medical Center Utrecht, The Netherlands.
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96
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Wani Y, Notohara K, Saegusa M, Tsukayama C. Aberrant Cdx2 expression in endometrial lesions with squamous differentiation: important role of Cdx2 in squamous morula formation. Hum Pathol 2008; 39:1072-9. [PMID: 18495206 DOI: 10.1016/j.humpath.2007.07.019] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/12/2007] [Revised: 06/15/2007] [Accepted: 07/26/2007] [Indexed: 12/15/2022]
Abstract
Only a few reports have described Cdx2 expression in endometrial lesions of the uterus. Our aim was to determine whether Cdx2 expression is related to squamous differentiation in endometrial lesions. Furthermore, we examined whether there is any correlation between Cdx2 and beta-catenin, a well-known marker of aberrant nuclear accumulation in endometrial squamous foci secondary to mutation. We performed immunohistochemical analysis of 225 cases (29 normal endometrium, 28 nonproliferative conditions, 21 polyps, 46 hyperplasias, and 101 endometrioid carcinomas) that included 72 cases (4 polyps, 16 hyperplasias, and 52 carcinomas) showing morular or keratinizing squamous differentiation (SD(+)). Normal endometrium and nonproliferative conditions showed no staining for Cdx2. Whereas there was a low rate of Cdx2 positivity in SD(-) polyps (5.9%) and hyperplasias (10%), all SD(+) lesions expressed Cdx2 (P < .001). Thirty-eight (73%) of the SD(+) carcinomas were positive for Cdx2, whereas only 6 SD(-) cases (14.0%) were positive (P < .001). Furthermore, the larger the number of squamous foci, the greater the number of Cdx2-positive cells that was found. The labeling indices of Cdx2 were significantly higher in morular components than in keratinizing or glandular ones (P < .001). There was a strong correlation of the labeling indices of Cdx2 and beta-catenin in squamous foci of hyperplasias and carcinomas. Using immunofluorescence, we confirmed the coexpression of the 2 markers. The Cdx2 protein is expressed frequently in endometrial lesions with squamous differentiation, especially morular-type differentiation, and correlates strongly with nuclear beta-catenin expression. These facts suggest that Cdx2 plays an important role in squamous morula formation.
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Affiliation(s)
- Yoji Wani
- Department of Pathology, Kurashiki Central Hospital, Kurashiki, Japan.
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97
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Valente AJ, Zhou Q, Lu Z, He W, Qiang M, Ma W, Li G, Wang L, Banfi B, Steger K, Krause KH, Clark RA, Li S. Regulation of NOX1 expression by GATA, HNF-1alpha, and Cdx transcription factors. Free Radic Biol Med 2008; 44:430-43. [PMID: 18005670 DOI: 10.1016/j.freeradbiomed.2007.10.035] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/21/2007] [Revised: 10/05/2007] [Accepted: 10/06/2007] [Indexed: 11/20/2022]
Abstract
NOX1, a member of the NOX family of NADPH oxidases, is expressed primarily in colon epithelium, where it may function in host defense and growth regulation. We investigated factors responsible for its transcriptional regulation in vitro and its expression in vivo. Analysis of promoter constructs in the CaCo2 cell line identified a complex element between -422 and -291 critical for promoter activity. This element contained four sites that bound GATA-4, -5, and -6 in vitro with varied affinities. One site also bound the caudal-related homeodomain proteins Cdx1 and Cdx2, whereas another also bound hepatocyte nuclear factor-1alpha (HNF-1alpha). GATA-6, HNF-1alpha, and Cdx2 also bound to this region in the intact chromatin of CaCo2 cells. These factors demonstrated cooperativity when transactivating the NOX1 promoter. NOX1 mRNA was detected in human colon epithelial cells along the crypt-villus axis. A gradient of NOX1 mRNA expression was seen in the colons of normal as well as germ-free mice, with significantly higher levels in distal compared with proximal segments. The expression gradients of NOX1 mRNA in the colon paralleled those of GATA-6, HNF-1alpha, and Cdx1. These data indicate that developmental, tissue-restricted transcription factors play a key role in NOX1 regulation in vivo.
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Affiliation(s)
- Anthony J Valente
- Department of Medicine, University of Texas Health Science Center, San Antonio, TX 78229-3900, USA.
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Tonini G, Pantano F, Vincenzi B, Gabbrielli A, Coppola R, Santini D. Molecular prognostic factors in patients with pancreatic cancer. Expert Opin Ther Targets 2007; 11:1553-69. [DOI: 10.1517/14728222.11.12.1553] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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Chen KH, Mukaisho KI, Sugihara H, Araki Y, Yamamoto G, Hattori T. High animal-fat intake changes the bile-acid composition of bile juice and enhances the development of Barrett's esophagus and esophageal adenocarcinoma in a rat duodenal-contents reflux model. Cancer Sci 2007; 98:1683-8. [PMID: 17868414 PMCID: PMC11158926 DOI: 10.1111/j.1349-7006.2007.00605.x] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2007] [Revised: 07/17/2007] [Accepted: 07/23/2007] [Indexed: 12/28/2022] Open
Abstract
The dietary components responsible for the development of Barrett's esophagus (BE) and esophageal adenocarcinoma (EAC) remain unclear. Wistar rats were divided into four groups based on their diet: a low soybean-oil diet, a low cow-fat diet, a high soybean-oil diet, and a high cow-fat diet. First, we evaluated the bile acid composition of the bile juice in each group without operation, using high-performance liquid chromatography. Because only high cow-fat intake induced changes in the composition of bile acids in bile juice, we then selected animals fed with a low soybean-oil diet and those with a high cow-fat diet to carry out esophago-jejunostomy for reflux of the duodenal contents, and compared sequential morphological changes between these groups up to 30 weeks after surgery. At 30 weeks after surgery, the reflux animals in the high cow-fat group showed a significantly higher incidence of BE and Barrett's dysplasia than those in the low soybean-oil group, and the incidence of EAC in the high cow-fat group was also slightly higher than that in the low soybean-oil group. High dietary animal fat changed the bile-acid composition and increased the concentration of taurine conjugates in the bile juice. These increased bile acids promoted the development of BE and Barrett's dysplasia leading to EAC.
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Affiliation(s)
- Kuan-Hao Chen
- Department of Pathology and Department of Oral and Maxillofacial Surgery, Shiga University of Medical Science, Seta-tsukinowa-cho, Ohtsu, Shiga 520-2192, USA
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Rawat VPS, Thoene S, Naidu VM, Arseni N, Heilmeier B, Metzeler K, Petropoulos K, Deshpande A, Quintanilla-Martinez L, Bohlander SK, Spiekermann K, Hiddemann W, Feuring-Buske M, Buske C. Overexpression of CDX2 perturbs HOX gene expression in murine progenitors depending on its N-terminal domain and is closely correlated with deregulated HOX gene expression in human acute myeloid leukemia. Blood 2007; 111:309-19. [PMID: 17855634 DOI: 10.1182/blood-2007-04-085407] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
The mechanisms underlying deregulation of HOX gene expression in AML are poorly understood. The ParaHox gene CDX2 was shown to act as positive upstream regulator of several HOX genes. In this study, constitutive expression of Cdx2 caused perturbation of leukemogenic Hox genes such as Hoxa10 and Hoxb8 in murine hematopoietic progenitors. Deletion of the N-terminal domain of Cdx2 abrogated its ability to perturb Hox gene expression and to cause acute myeloid leukemia (AML) in mice. In contrast inactivation of the putative Pbx interacting site of Cdx2 did not change the leukemogenic potential of the gene. In an analysis of 115 patients with AML, expression levels of CDX2 were closely correlated with deregulated HOX gene expression. Patients with normal karyotype showed a 14-fold higher expression of CDX2 and deregulated HOX gene expression compared with patients with chromosomal translocations such as t(8:21) or t(15;17). All patients with AML with normal karyotype tested were negative for CDX1 and CDX4 expression. These data link the leukemogenic potential of Cdx2 to its ability to dysregulate Hox genes. They furthermore correlate the level of CDX2 expression with HOX gene expression in human AML and support a potential role of CDX2 in the development of human AML with aberrant Hox gene expression.
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