AIM: To study the expression of HBV enhancer Ⅱ by transcription factor COUP-TF1. METHODS: In order to study the regulation of HBV variants in the vicinity of the NRRE we cloned luciferase constructs containing the HB...AIM: To study the expression of HBV enhancer Ⅱ by transcription factor COUP-TF1. METHODS: In order to study the regulation of HBV variants in the vicinity of the NRRE we cloned luciferase constructs containing the HBV enhancer Ⅱ from variants and from HBV genotypes A and D and cotransfected them together with expression vectors for COUP-TF1 into HepG2 cells. RESULTS: Our fi ndings show that enhancer Ⅱ of HBV genotype A is also repressed by COUP-TF1. In contrast, two different enhancer Ⅱ constructs of HBV genotype D were activated by COUP-TF1. The activation was independent of the NRRE because a natural variant with a deletion of nt 1763-1770 was still activated by COUP- TF1. CONCLUSION: Regulation of transcription of the HBV genome seems to differ among HBV genomes derived from different genotypes. These differences in transcriptional control among HBV genotypes may be the molecular basis for differences in the clinical course among HBV genotypes.展开更多
Pancreatic ductal adenocarcinoma (PDAC) is a devastating disease with a median overall survival time of 5 mo and the five years survival less than 5%, a rate essentially unchanged over the course of the years. A well ...Pancreatic ductal adenocarcinoma (PDAC) is a devastating disease with a median overall survival time of 5 mo and the five years survival less than 5%, a rate essentially unchanged over the course of the years. A well defined progression model of accumulation of genetic alterations ranging from single point mutations to gross chromosomal abnormalities has been introduced to describe the origin of this disease. However, due to the its subtle nature and concurring events PDAC cure remains elusive. Nuclear receptors (NR) are members of a large superfamily of evolutionarily conserved ligand-regulated DNA-binding transcription factors functionally involved in important cellular functions ranging from regulation of metabolism, to growth and development. Given the nature of their ligands, NR are very tempting drug targets and their pharmacological modulation has been widely exploited for the treatment of metabolic and inflammatory diseases. There are now clear evidences that both classical ligand-activated and orphan NR are involved in the pathogenesis of PDAC from its very early stages; nonetheless many aspects of their role are not fully understood. The purpose of this review is to highlight the striking connections that link peroxisome proliferator activated receptors, retinoic acid receptors, retinoid X receptor, androgen receptor, estrogen receptors and the orphan NR Nur, chicken ovalbumin upstream promoter transcription factor II and the liver receptor homologue-1 receptor to PDAC development, connections that could lead to the identification of novel therapies for this disease.展开更多
Objective: To investigate the changes and mechanism of angiogenesis in myocardium induced by transplantation of the sonic hedgehog (shh) gene transfected in bone marrow mesenchymal stem cells (BMMSC) after myocardial ...Objective: To investigate the changes and mechanism of angiogenesis in myocardium induced by transplantation of the sonic hedgehog (shh) gene transfected in bone marrow mesenchymal stem cells (BMMSC) after myocardial infarction. Methods: A rat model of acute myocardial infarction was made by coronary artery ligation. The rats were randomly divided into five groups of 40 rats each. These were further subdivided into groups of 10 rats. The peripheral regions of the infarcts were injected with either BMMSCSHH (transfection group), equivalent BMMSC (cell only group), BMMSC and pcDNA3.1-Shh DNA mixture (mixture group), pcDNA3.1-shh DNA alone (gene only group), or equal volumes of low-sugar DMEM medium (control group). One, two, four, and eight weeks after transplantation, specimens were harvested from the transplantation site to determine the expression of SHH signaling pathway downstream genes Ptc1, Gli-2, COUP-TF II, angiogenesis promoting factor VEGF, and Ang-1 using RT-PCR. Results: Seven days after transplantation, the expression of SHH signaling pathway downstream genes, Ptc1, Gli-2, and COUP-TF II was significantly more pronounced in the transfection group than in the control group, cell only group, gene only group, or mixture group (Ptc1: P P P < 0.05, and P COUP-TF II: P P P P Gli-2: P P P < 0.05, and P < 0.05, respectively). The expression of angiogenesis-promoting genes Vegf and Ang-1 was significantly more pronounced than in the control group, cell only group, or gene only group (Vegf: P P P Ang-1: P P P < 0.05, respectively). Conclusion: Transplantation of the shh-gene-transfected BMMSCs to the peripheral regions of myocardial infarcts promoted angiogenesis by upregulating downstream gene expression.展开更多
基金Supported by grant 10-1854-Scha I from Deutsche Krebshilfe, grant Scha778/2-1 from DFG to S.S. and Graduiertenkolleg Nu-cleoprotein complexes to S.S. and W.H.G.
文摘AIM: To study the expression of HBV enhancer Ⅱ by transcription factor COUP-TF1. METHODS: In order to study the regulation of HBV variants in the vicinity of the NRRE we cloned luciferase constructs containing the HBV enhancer Ⅱ from variants and from HBV genotypes A and D and cotransfected them together with expression vectors for COUP-TF1 into HepG2 cells. RESULTS: Our fi ndings show that enhancer Ⅱ of HBV genotype A is also repressed by COUP-TF1. In contrast, two different enhancer Ⅱ constructs of HBV genotype D were activated by COUP-TF1. The activation was independent of the NRRE because a natural variant with a deletion of nt 1763-1770 was still activated by COUP- TF1. CONCLUSION: Regulation of transcription of the HBV genome seems to differ among HBV genomes derived from different genotypes. These differences in transcriptional control among HBV genotypes may be the molecular basis for differences in the clinical course among HBV genotypes.
基金Supported by Fondo per gli Investimenti della Ricerca di Base(FIRB)(RBAP10MY35_002)by Ente Cassa di Risparmio di Firenzeby FiorGen ONLUS to Galli A
文摘Pancreatic ductal adenocarcinoma (PDAC) is a devastating disease with a median overall survival time of 5 mo and the five years survival less than 5%, a rate essentially unchanged over the course of the years. A well defined progression model of accumulation of genetic alterations ranging from single point mutations to gross chromosomal abnormalities has been introduced to describe the origin of this disease. However, due to the its subtle nature and concurring events PDAC cure remains elusive. Nuclear receptors (NR) are members of a large superfamily of evolutionarily conserved ligand-regulated DNA-binding transcription factors functionally involved in important cellular functions ranging from regulation of metabolism, to growth and development. Given the nature of their ligands, NR are very tempting drug targets and their pharmacological modulation has been widely exploited for the treatment of metabolic and inflammatory diseases. There are now clear evidences that both classical ligand-activated and orphan NR are involved in the pathogenesis of PDAC from its very early stages; nonetheless many aspects of their role are not fully understood. The purpose of this review is to highlight the striking connections that link peroxisome proliferator activated receptors, retinoic acid receptors, retinoid X receptor, androgen receptor, estrogen receptors and the orphan NR Nur, chicken ovalbumin upstream promoter transcription factor II and the liver receptor homologue-1 receptor to PDAC development, connections that could lead to the identification of novel therapies for this disease.
文摘Objective: To investigate the changes and mechanism of angiogenesis in myocardium induced by transplantation of the sonic hedgehog (shh) gene transfected in bone marrow mesenchymal stem cells (BMMSC) after myocardial infarction. Methods: A rat model of acute myocardial infarction was made by coronary artery ligation. The rats were randomly divided into five groups of 40 rats each. These were further subdivided into groups of 10 rats. The peripheral regions of the infarcts were injected with either BMMSCSHH (transfection group), equivalent BMMSC (cell only group), BMMSC and pcDNA3.1-Shh DNA mixture (mixture group), pcDNA3.1-shh DNA alone (gene only group), or equal volumes of low-sugar DMEM medium (control group). One, two, four, and eight weeks after transplantation, specimens were harvested from the transplantation site to determine the expression of SHH signaling pathway downstream genes Ptc1, Gli-2, COUP-TF II, angiogenesis promoting factor VEGF, and Ang-1 using RT-PCR. Results: Seven days after transplantation, the expression of SHH signaling pathway downstream genes, Ptc1, Gli-2, and COUP-TF II was significantly more pronounced in the transfection group than in the control group, cell only group, gene only group, or mixture group (Ptc1: P P P < 0.05, and P COUP-TF II: P P P P Gli-2: P P P < 0.05, and P < 0.05, respectively). The expression of angiogenesis-promoting genes Vegf and Ang-1 was significantly more pronounced than in the control group, cell only group, or gene only group (Vegf: P P P Ang-1: P P P < 0.05, respectively). Conclusion: Transplantation of the shh-gene-transfected BMMSCs to the peripheral regions of myocardial infarcts promoted angiogenesis by upregulating downstream gene expression.
