Background： Vein graft failure （VGF） is a serious complication of coronary artery bypass graft, although the mechanism remains unclear. The study aimed to investigate the effects of microRNAs （miRNAs） on the endo...Background： Vein graft failure （VGF） is a serious complication of coronary artery bypass graft, although the mechanism remains unclear. The study aimed to investigate the effects of microRNAs （miRNAs） on the endothelial dysfunction involved in VGF. Methods： Human umbilical vein endothelial cells （HUVECs） were subjected to mechanical stretch stimulation to induce endothelial dysfunction. Genome-wide transcriptome profiling was performed using the Human miRNA OneArray＂ V4 （PhalanxBio Inc., San Diego, USA）. The miRNA-messenger RNA （mRNA） network was investigated using gene ontology and Kyoto Encyclopedia of Genes and Genomes. The miR-55 1b-5p mimic and inhibitor were applied to regulate miR-55 lb-5p expression in the HUVECs. The 5-ethynyl-2＇-deoxyuridine assay, polymerase chain reaction （PCR）, and Western blotting （WB） were used to assess HUVECs proliferation, mRNA expression, and protein expression, respectively. The vein graft model was established in early growth response （Egr）-I knockout （KO） mice and wide-type （WT） C57BL/6J mice for pathological and immunohistochemical analysis. Endothelial cells isolated from the veins of WT and Egr-1 KO mice were subjected to mechanical stretch stimulation; PCR and WB were conducted to confirm the regulatory effect of Egr- 1 on Intercellular adhesion molecule （loam-1）. One-way analysis of variance and independent t-test were performed for data analysis. Results： Thirty-eight rniRNAs were differentially expressed in HUVECs after mechanical stretch stimulation. The bioinforrnatics analysis revealed that Egr-1 might be involved in VGF and was a potential target gene of miR-551b-5p. The mechanical stretch stimulation increased miR-55 1b-5p expression by 2.93 ± 0.08 told （t= 3.07, P 〈 0.05）, compared with the normal HUVECs. Transfection with the miR-551b-5p mimic or inhibitor increased expression of miR-551b-5p by 793.1 ± 171.6 fold （t = 13.84, P 〈 0.001） or decreased by 26.3% ± 2.4% （t= 26.39, P 〈 0.05） in the HUVECs, respectively. HUVECs proliferation and EGR-I mRNA expression were significantly suppressed by inhibiting miR-551b-5p expression （P 〈 0.05）. The lumens of the vein grafts in the Egr-1 KO mice were wider than that in the WT mice. lcam-I expression was suppressed significantly in the Egr-1 KO vein grafts （P 〈 0.05）. Conclusions： Increased miR-55 1b-5p expression leads to endothelial dysfunction by upregulating Egr-1 expression. EGR-1 KO can improve the function of a grafted vein through suppressing loam-1.展开更多
Background: Cyclooxygenase-2 (COX-2) and transforming growth factor-beta1 (TGF-β1) are modulated in variety cancers including Hepatocellular carcinoma (HCC). However, there is a paucity of data concerning their role ...Background: Cyclooxygenase-2 (COX-2) and transforming growth factor-beta1 (TGF-β1) are modulated in variety cancers including Hepatocellular carcinoma (HCC). However, there is a paucity of data concerning their role in the pathologic process of recurrence of HCC following hepatectomy. We herein assessed the role of the hepatic expression of COX-2 and TGF-β as predictors for patients with early recurrence within 2 years of HCC diagnosis. Methods: Sixty patients with HCC who underwent curative hepatectomy between 2000 and 2003 were entered in the present study. The immunoreactivity and distribution patterns of COX-2 and TGF-β1 were examined in both the HCC and the adjacent nonHCC tissues of the liver. Risk factors of tumor recurrence within 2 years, including COX-2 and TGF-β1 expression, were investigated by univariate and multivariate analyses. Results: Among 60 patients, 31 patients had early recurrences within 2 years and 14 patients recurred after 2 years following surgery. Patients with low COX-2 expression in the HCC tissues and adjacent nonHCC tissues had favorable disease-free survival (p = 0.002 and p β1 expression in the nonHCC tissues had also longer disease-free survival (p = 0.045). Based on the expression patterns of COX-2 and TGF-β1, patients with low COX-2 and positive TGF-β1 expression in the nonHCC tissues had favorable overall and disease-free survival (p β1 signaling in nontumor tissues suggested high risk of recurrence and poor survival to the HCC patients following hepatectomy.展开更多
BACKGROUND： Insulin-like growth factor-I（IGF-1）, as one of the important members of growth factor family, participants in the regulation of many physiological functions and behaviors, having very strong neuroprotec...BACKGROUND： Insulin-like growth factor-I（IGF-1）, as one of the important members of growth factor family, participants in the regulation of many physiological functions and behaviors, having very strong neuroprotective effect. However, the expression of IGF-1 following cerebral ischemia/reperfusion is still disputed. OBJECTIVE： To observe the expression of IGF-1 and protein of corpora striata in ischemic side at the early stage of middle cerebral artery ischemia/reperfusion in rhesus monkey. DESIGN ： A completely randomized grouping design, controlled animal experiment SETTING ： Institute of Cerebrovascular Disease, Affiliated Hospital of Medical College of Qingdao University MATERIALS： ① Totally 17 rhesus monkeys , of either gender, aged 4 to 5 years, were enrolled . Seven rhesus monkeys observed with gene chip were randomly divided into 2 groups： sham operation group （n=3） and ischemia/reperfusion group 〈n=4〉. Ten rhesus monkeys observed with in situ hybridization and immunohistochemistry method were randomly divided into 2 groups： sham operation group 〈n=3 〉and ischemia/reperfusion group （n=7）. Rhesus monkeys observed under microscope were divided into 2 groups： sham operation group （n=6） and ischamia/reperfusion group （n=-11）.②Materials used in the experiment： cresyl violet （Sigma Company, America）; immunohistochemical reagent kit （ Huamei Bio-engineering Company）; In situ hybridization reagent kit （Boshide Bio-engineering Co.Ltd, Wuhan）; 12 800 dots chip （Boxing Company, Shanghai）. METHODS ： This experiment was carried out at the Institute of Cerebrovascular Disease, Affiliated Hospital of Medical College of Qingdao University from January 2001 to December 2003.① The onset area of middle cerebral artery was blocked for 2 hours, middle cerebral artery ischemia/reperfusion models were created.② After ischemia/reperfusion for 24 hours, cerebral tissue sections of rhesus monkeys were prepared and stained with cresyl violet. Image analysis was performed with 5001W image analysis software. Morphological change of corpora striata of operative side was observed in the rhesus monkeys between two groups. Total RNA was extracted from cerebral tissue. ③ Detection of gene chip： Cy3-duTP and Cy5-duTP were used to respectively perform reverse transcription labeling. The sample was reversely transcribed into cDNA, then hybridized with cDNA of cerebral tissue. Genes with the separate absolute value of cy3 and cy5〉800, cY3/cy5 〉 2（high expression） or 〈 0.5 （low expression） were found out. Those were genes with differential expression. ④ The expressions of IGF-1 mRNA and protein level of corpora striata in ischemic side of rhe- sus monkeys were detected between sham operation group and ischemia/reperfusion group at 9 and 24 hours after ischemia/reperfusion with in situ hybridization method and immunohistochemical method. Brown granules were IGF-1 protein positive cells. ⑤ Analysis of variance was used in the difference comparison of measurement data among groups. MAIN OUTCOME MEASURES ： ① Change of morphological structure of corpora striata at ischemic side in rhesus monkeys. ② Change of cerebral gene expression profiles at ischemia/reperfusion in rhesus monkeys between two groups.③ Expression of IGF-1 mRNA and protein level of corpora striata at ischemia/reperfu- sion in rhesus monkeys between two groups. RESULTS ： ① Pathological change ： Obvious pathological change of cerebral infarction appeared in the ischemia and reperfusion group, while there was no such pathological change in the sham operation group.② Change of gene expression profile ： There were 4480 genes with difference expression in the ischemia/reperfusion group and sham-operation group, in which, 260 genes had high expression and their absolute value was over 800, and 63 genes had low expression, cy3/cy5 of IGF-1 was 0.379, being relative low ex- pression. ③ IGF-1 mRNA and protein positive cell counts in corpora striata at cerebral ischemic side[IGF-1 mRNA： 〈9.72±1.18）,（9.11 ±0.76）,（14.77±0.60） counts/field：lGF-1 protein： （15.11 ±1.83）,（15.39±0.78）, （34.62±0.97）counts/field, P 〈 0.05-0.01]. CONCLUSION： IGF-1 mRNA and protein are lowly expressed in middle cerebral artery of rhesus monkeys at ischemia/reperfusion.展开更多
OBJECTIVE Basic fibroblast growth factor(b FGF)and platelet-derived growth factor(PDGF)produced by hepatocellular carcinoma(HCC)cells are responsible for the cell growth.Accumulating evidence shows that insulin-like g...OBJECTIVE Basic fibroblast growth factor(b FGF)and platelet-derived growth factor(PDGF)produced by hepatocellular carcinoma(HCC)cells are responsible for the cell growth.Accumulating evidence shows that insulin-like growth factor-binding protein-3(IGFBP-3)suppresses HCC cell proliferation in both IGF-dependent and independent manners.The present study is to investigate whether treatment with exogenous IGFBP-3 inhibits bF GF and PDGF production and the cell proliferation of HCC cells.METHODS Cell Counting Kit 8 assay were designed to detect HCC cell proliferation,transcription factor early growth response-1(EGR1)involving in IGFBP-3 regulation of b FGF and PDGF were detected by RT-PCR and Western blot assays.Western blot assay was adopted to detect the IGFBP-3 regulating insulin-like growth factor 1 receptor(IGF-1R)signaling pathway.RESULTS The present study demonstrates that IGFBP-3 suppressed IGF-1-induced b FGF and PDGF expression while it does not affect their expression in the absence of IGF-1.To delineate the underlying mechanism,Western-blot and RT-PCR assays confirmed that the transcription factor early growth response protein 1(EGR1)is involved in IGFBP-3 regulation of b FGF and PDGF.IGFBP-3 inhibition of type 1 insulin-like growth factor receptor(IGF1R),ERK and AKT activation is IGF-1-dependent.Furthermore,transient transfection with constitutively activated AKT or MEK partially blocks the IGFBP-3 inhibition of EGR1,b FGF and PDGF expression.CONCLUSION In conclusion,these findings suggest that IGFBP-3suppresses transcription of EGR1 and its target genes b FGF and PDGF through inhibiting IGF-1-dependent ERK and AKT activation.It demonstrates the importance of IGFBP-3 in the regulation of HCC cell proliferation,suggesting that IGFBP-3 could be a target for the treatment of HCC.展开更多
Early growth response protein 1(Egr-1)triggers the transcription of many genes involved in cell growth,differentiation,synaptic plasticity,and neurogenesis.However,its mechanism in neuronal survival and degeneration i...Early growth response protein 1(Egr-1)triggers the transcription of many genes involved in cell growth,differentiation,synaptic plasticity,and neurogenesis.However,its mechanism in neuronal survival and degeneration is still poorly understood.This study demonstrated that Egr-1 was down-regulated at mRNA and protein levels in the central nervous system(CNS)of experimental autoimmune encephalomyelitis(EAE)mice.Egr-1 knockout exacerbated EAE progression in mice,as shown by increased disease severity and incidence;it also aggravated neuronal apoptosis,which was associated with weakened activation of the BDNF/TGFβ1/MAPK/Akt signaling pathways in the CNS of EAE mice.Consistently,Egr-1 siRNA promoted apoptosis but mitigated the activation of BDNF/TGFβ1/MAPK/Akt signaling in SH-SY5Y cells.Our results revealed that Egr-1 is a crucial regulator of neuronal survival in EAE by regulating TGFβ1-mediated signaling activation,implicating the important role of Egr-1 in the pathogenesis of multiple sclerosis as a potential novel therapy target.展开更多
AIM:To investigate the role of transforming growth factor(TGF)-β-inducible early gene 1(TIEG1) in TGF-β-induced growth inhibition in hepatocellular carcinoma(HCC) cells.METHODS:Human hepatocyte and HCC cell lines wi...AIM:To investigate the role of transforming growth factor(TGF)-β-inducible early gene 1(TIEG1) in TGF-β-induced growth inhibition in hepatocellular carcinoma(HCC) cells.METHODS:Human hepatocyte and HCC cell lines with varied susceptibilities to TGF-β1 were tested by methylthiazoletetrazolium(MTT) assay.The expression changes of Smad2,Smad3,Smad4,Smad7,TIEG1 and TIEG2 gene following treatment with TGF-β1 in a TGF-β-sensitive hepatocyte cell line(MIHA),a TGF-β-sensitive hepatoma cell line(Hep3B) and two TGF-β-insensitive hepatoma cell lines(HepG2 and Bel7404) were examined.SiRNA targeting TIEG1 was transfected into Hep3B cells and the sensitivity of cells to TGF-β1 was examined.Overexpression of TIEG1 was induced by lentiviral-mediated transduction in TGF-β1-resistant hepatoma cell lines(Bel7404 and HepG2).MTT assay and 4',6-Diamidino-2-phenylindole staining were used to identify cell viability and apoptosis,respectively.The expression level of stathmin was measured by reverse transcriptase polymerase chain reaction and Western-blotting analysis,and stathmin promoter activity by TIEG1 was monitored by a luciferase reporter gene system.RESULTS:TIEG1 was significantly upregulated by TGF-β1 in the TGF-β1-sensitive HCC cell line,Hep3B,but not in the resistant cell lines.The suppression of TIEG1 by siRNAs decreased the sensitivity of Hep3B cells to TGF-β1,whereas the overexpression of TIEG1 mediated growth inhibition and apoptosis in TGF-β1-resistant HCC cell lines,which resembled those of TGF-β1-sensitive HCC cells treated with TGF-β1.Our data further suggested that stathmin was a direct target of TIEG1,as stathmin was signif icantly downregulated by TIEG1 overexpression,and stathmin promoter activity was inhibited by TIEG1 in a dose-dependent manner.CONCLUSION:Our data suggest that transactivation of TIEG1 conferred growth inhibition of TGF-β-susceptible human HCC cells.展开更多
基金This study was partly supported by grants from the National Natural Science Foundation of China （No. 81570373, No. 81170283, No. 81470580, and No. 81070202）.
文摘Background： Vein graft failure （VGF） is a serious complication of coronary artery bypass graft, although the mechanism remains unclear. The study aimed to investigate the effects of microRNAs （miRNAs） on the endothelial dysfunction involved in VGF. Methods： Human umbilical vein endothelial cells （HUVECs） were subjected to mechanical stretch stimulation to induce endothelial dysfunction. Genome-wide transcriptome profiling was performed using the Human miRNA OneArray＂ V4 （PhalanxBio Inc., San Diego, USA）. The miRNA-messenger RNA （mRNA） network was investigated using gene ontology and Kyoto Encyclopedia of Genes and Genomes. The miR-55 1b-5p mimic and inhibitor were applied to regulate miR-55 lb-5p expression in the HUVECs. The 5-ethynyl-2＇-deoxyuridine assay, polymerase chain reaction （PCR）, and Western blotting （WB） were used to assess HUVECs proliferation, mRNA expression, and protein expression, respectively. The vein graft model was established in early growth response （Egr）-I knockout （KO） mice and wide-type （WT） C57BL/6J mice for pathological and immunohistochemical analysis. Endothelial cells isolated from the veins of WT and Egr-1 KO mice were subjected to mechanical stretch stimulation; PCR and WB were conducted to confirm the regulatory effect of Egr- 1 on Intercellular adhesion molecule （loam-1）. One-way analysis of variance and independent t-test were performed for data analysis. Results： Thirty-eight rniRNAs were differentially expressed in HUVECs after mechanical stretch stimulation. The bioinforrnatics analysis revealed that Egr-1 might be involved in VGF and was a potential target gene of miR-551b-5p. The mechanical stretch stimulation increased miR-55 1b-5p expression by 2.93 ± 0.08 told （t= 3.07, P 〈 0.05）, compared with the normal HUVECs. Transfection with the miR-551b-5p mimic or inhibitor increased expression of miR-551b-5p by 793.1 ± 171.6 fold （t = 13.84, P 〈 0.001） or decreased by 26.3% ± 2.4% （t= 26.39, P 〈 0.05） in the HUVECs, respectively. HUVECs proliferation and EGR-I mRNA expression were significantly suppressed by inhibiting miR-551b-5p expression （P 〈 0.05）. The lumens of the vein grafts in the Egr-1 KO mice were wider than that in the WT mice. lcam-I expression was suppressed significantly in the Egr-1 KO vein grafts （P 〈 0.05）. Conclusions： Increased miR-55 1b-5p expression leads to endothelial dysfunction by upregulating Egr-1 expression. EGR-1 KO can improve the function of a grafted vein through suppressing loam-1.
文摘Background: Cyclooxygenase-2 (COX-2) and transforming growth factor-beta1 (TGF-β1) are modulated in variety cancers including Hepatocellular carcinoma (HCC). However, there is a paucity of data concerning their role in the pathologic process of recurrence of HCC following hepatectomy. We herein assessed the role of the hepatic expression of COX-2 and TGF-β as predictors for patients with early recurrence within 2 years of HCC diagnosis. Methods: Sixty patients with HCC who underwent curative hepatectomy between 2000 and 2003 were entered in the present study. The immunoreactivity and distribution patterns of COX-2 and TGF-β1 were examined in both the HCC and the adjacent nonHCC tissues of the liver. Risk factors of tumor recurrence within 2 years, including COX-2 and TGF-β1 expression, were investigated by univariate and multivariate analyses. Results: Among 60 patients, 31 patients had early recurrences within 2 years and 14 patients recurred after 2 years following surgery. Patients with low COX-2 expression in the HCC tissues and adjacent nonHCC tissues had favorable disease-free survival (p = 0.002 and p β1 expression in the nonHCC tissues had also longer disease-free survival (p = 0.045). Based on the expression patterns of COX-2 and TGF-β1, patients with low COX-2 and positive TGF-β1 expression in the nonHCC tissues had favorable overall and disease-free survival (p β1 signaling in nontumor tissues suggested high risk of recurrence and poor survival to the HCC patients following hepatectomy.
基金the Natural Science Foundation of Shandong Province, No. Y2004C04
文摘BACKGROUND： Insulin-like growth factor-I（IGF-1）, as one of the important members of growth factor family, participants in the regulation of many physiological functions and behaviors, having very strong neuroprotective effect. However, the expression of IGF-1 following cerebral ischemia/reperfusion is still disputed. OBJECTIVE： To observe the expression of IGF-1 and protein of corpora striata in ischemic side at the early stage of middle cerebral artery ischemia/reperfusion in rhesus monkey. DESIGN ： A completely randomized grouping design, controlled animal experiment SETTING ： Institute of Cerebrovascular Disease, Affiliated Hospital of Medical College of Qingdao University MATERIALS： ① Totally 17 rhesus monkeys , of either gender, aged 4 to 5 years, were enrolled . Seven rhesus monkeys observed with gene chip were randomly divided into 2 groups： sham operation group （n=3） and ischemia/reperfusion group 〈n=4〉. Ten rhesus monkeys observed with in situ hybridization and immunohistochemistry method were randomly divided into 2 groups： sham operation group 〈n=3 〉and ischemia/reperfusion group （n=7）. Rhesus monkeys observed under microscope were divided into 2 groups： sham operation group （n=6） and ischamia/reperfusion group （n=-11）.②Materials used in the experiment： cresyl violet （Sigma Company, America）; immunohistochemical reagent kit （ Huamei Bio-engineering Company）; In situ hybridization reagent kit （Boshide Bio-engineering Co.Ltd, Wuhan）; 12 800 dots chip （Boxing Company, Shanghai）. METHODS ： This experiment was carried out at the Institute of Cerebrovascular Disease, Affiliated Hospital of Medical College of Qingdao University from January 2001 to December 2003.① The onset area of middle cerebral artery was blocked for 2 hours, middle cerebral artery ischemia/reperfusion models were created.② After ischemia/reperfusion for 24 hours, cerebral tissue sections of rhesus monkeys were prepared and stained with cresyl violet. Image analysis was performed with 5001W image analysis software. Morphological change of corpora striata of operative side was observed in the rhesus monkeys between two groups. Total RNA was extracted from cerebral tissue. ③ Detection of gene chip： Cy3-duTP and Cy5-duTP were used to respectively perform reverse transcription labeling. The sample was reversely transcribed into cDNA, then hybridized with cDNA of cerebral tissue. Genes with the separate absolute value of cy3 and cy5〉800, cY3/cy5 〉 2（high expression） or 〈 0.5 （low expression） were found out. Those were genes with differential expression. ④ The expressions of IGF-1 mRNA and protein level of corpora striata in ischemic side of rhe- sus monkeys were detected between sham operation group and ischemia/reperfusion group at 9 and 24 hours after ischemia/reperfusion with in situ hybridization method and immunohistochemical method. Brown granules were IGF-1 protein positive cells. ⑤ Analysis of variance was used in the difference comparison of measurement data among groups. MAIN OUTCOME MEASURES ： ① Change of morphological structure of corpora striata at ischemic side in rhesus monkeys. ② Change of cerebral gene expression profiles at ischemia/reperfusion in rhesus monkeys between two groups.③ Expression of IGF-1 mRNA and protein level of corpora striata at ischemia/reperfu- sion in rhesus monkeys between two groups. RESULTS ： ① Pathological change ： Obvious pathological change of cerebral infarction appeared in the ischemia and reperfusion group, while there was no such pathological change in the sham operation group.② Change of gene expression profile ： There were 4480 genes with difference expression in the ischemia/reperfusion group and sham-operation group, in which, 260 genes had high expression and their absolute value was over 800, and 63 genes had low expression, cy3/cy5 of IGF-1 was 0.379, being relative low ex- pression. ③ IGF-1 mRNA and protein positive cell counts in corpora striata at cerebral ischemic side[IGF-1 mRNA： 〈9.72±1.18）,（9.11 ±0.76）,（14.77±0.60） counts/field：lGF-1 protein： （15.11 ±1.83）,（15.39±0.78）, （34.62±0.97）counts/field, P 〈 0.05-0.01]. CONCLUSION： IGF-1 mRNA and protein are lowly expressed in middle cerebral artery of rhesus monkeys at ischemia/reperfusion.
基金supported by National Natural Science Foundation of China(81502123 and81330081)Natural Science Foundation of Anhui Province(1308085QH130)Anhui Province Nature Science Foundation in University(KJ2014A119)
文摘OBJECTIVE Basic fibroblast growth factor(b FGF)and platelet-derived growth factor(PDGF)produced by hepatocellular carcinoma(HCC)cells are responsible for the cell growth.Accumulating evidence shows that insulin-like growth factor-binding protein-3(IGFBP-3)suppresses HCC cell proliferation in both IGF-dependent and independent manners.The present study is to investigate whether treatment with exogenous IGFBP-3 inhibits bF GF and PDGF production and the cell proliferation of HCC cells.METHODS Cell Counting Kit 8 assay were designed to detect HCC cell proliferation,transcription factor early growth response-1(EGR1)involving in IGFBP-3 regulation of b FGF and PDGF were detected by RT-PCR and Western blot assays.Western blot assay was adopted to detect the IGFBP-3 regulating insulin-like growth factor 1 receptor(IGF-1R)signaling pathway.RESULTS The present study demonstrates that IGFBP-3 suppressed IGF-1-induced b FGF and PDGF expression while it does not affect their expression in the absence of IGF-1.To delineate the underlying mechanism,Western-blot and RT-PCR assays confirmed that the transcription factor early growth response protein 1(EGR1)is involved in IGFBP-3 regulation of b FGF and PDGF.IGFBP-3 inhibition of type 1 insulin-like growth factor receptor(IGF1R),ERK and AKT activation is IGF-1-dependent.Furthermore,transient transfection with constitutively activated AKT or MEK partially blocks the IGFBP-3 inhibition of EGR1,b FGF and PDGF expression.CONCLUSION In conclusion,these findings suggest that IGFBP-3suppresses transcription of EGR1 and its target genes b FGF and PDGF through inhibiting IGF-1-dependent ERK and AKT activation.It demonstrates the importance of IGFBP-3 in the regulation of HCC cell proliferation,suggesting that IGFBP-3 could be a target for the treatment of HCC.
基金supported by the National Natural Science Foundation of China(82074043,82104425,82374065,and 81673626)the China Postdoctoral Science Foundation(2021M702217).
文摘Early growth response protein 1(Egr-1)triggers the transcription of many genes involved in cell growth,differentiation,synaptic plasticity,and neurogenesis.However,its mechanism in neuronal survival and degeneration is still poorly understood.This study demonstrated that Egr-1 was down-regulated at mRNA and protein levels in the central nervous system(CNS)of experimental autoimmune encephalomyelitis(EAE)mice.Egr-1 knockout exacerbated EAE progression in mice,as shown by increased disease severity and incidence;it also aggravated neuronal apoptosis,which was associated with weakened activation of the BDNF/TGFβ1/MAPK/Akt signaling pathways in the CNS of EAE mice.Consistently,Egr-1 siRNA promoted apoptosis but mitigated the activation of BDNF/TGFβ1/MAPK/Akt signaling in SH-SY5Y cells.Our results revealed that Egr-1 is a crucial regulator of neuronal survival in EAE by regulating TGFβ1-mediated signaling activation,implicating the important role of Egr-1 in the pathogenesis of multiple sclerosis as a potential novel therapy target.
基金Supported by Hong Kong Research Grant Council,No.467109,467507the Scientif ic Research Fund of Zhejiang Provincial Ed-ucation Department,No.Y200906317+1 种基金the Wenzhou Science and Technology Bureau Program,No.Y20100017Qianjiang Talents Project of Zhejiang Province,No.2011R10058
文摘AIM:To investigate the role of transforming growth factor(TGF)-β-inducible early gene 1(TIEG1) in TGF-β-induced growth inhibition in hepatocellular carcinoma(HCC) cells.METHODS:Human hepatocyte and HCC cell lines with varied susceptibilities to TGF-β1 were tested by methylthiazoletetrazolium(MTT) assay.The expression changes of Smad2,Smad3,Smad4,Smad7,TIEG1 and TIEG2 gene following treatment with TGF-β1 in a TGF-β-sensitive hepatocyte cell line(MIHA),a TGF-β-sensitive hepatoma cell line(Hep3B) and two TGF-β-insensitive hepatoma cell lines(HepG2 and Bel7404) were examined.SiRNA targeting TIEG1 was transfected into Hep3B cells and the sensitivity of cells to TGF-β1 was examined.Overexpression of TIEG1 was induced by lentiviral-mediated transduction in TGF-β1-resistant hepatoma cell lines(Bel7404 and HepG2).MTT assay and 4',6-Diamidino-2-phenylindole staining were used to identify cell viability and apoptosis,respectively.The expression level of stathmin was measured by reverse transcriptase polymerase chain reaction and Western-blotting analysis,and stathmin promoter activity by TIEG1 was monitored by a luciferase reporter gene system.RESULTS:TIEG1 was significantly upregulated by TGF-β1 in the TGF-β1-sensitive HCC cell line,Hep3B,but not in the resistant cell lines.The suppression of TIEG1 by siRNAs decreased the sensitivity of Hep3B cells to TGF-β1,whereas the overexpression of TIEG1 mediated growth inhibition and apoptosis in TGF-β1-resistant HCC cell lines,which resembled those of TGF-β1-sensitive HCC cells treated with TGF-β1.Our data further suggested that stathmin was a direct target of TIEG1,as stathmin was signif icantly downregulated by TIEG1 overexpression,and stathmin promoter activity was inhibited by TIEG1 in a dose-dependent manner.CONCLUSION:Our data suggest that transactivation of TIEG1 conferred growth inhibition of TGF-β-susceptible human HCC cells.
