Objective Vascular smooth muscle cell(VSMC)differentiation from stem cells is one source of the increasing number of VSMCs that are involved in vascular remodeling-related diseases such as hypertension,atherosclerosis...Objective Vascular smooth muscle cell(VSMC)differentiation from stem cells is one source of the increasing number of VSMCs that are involved in vascular remodeling-related diseases such as hypertension,atherosclerosis,and restenosis.MicroRNA-146a(miR-146a)has been proven to be involved in cell proliferation,migration,and tumor metabolism.However,little is known about the functional role of miR-146a in VSMC differentiation from embryonic stem cells(ESCs).This study aimed to determine the role of miR-146a in VSMC differentiation from ESCs.Methods Mouse ESCs were differentiated into VSMCs,and the cell extracts were analyzed by Western blotting and RT-qPCR.In addition,luciferase reporter assays using ESCs transfected with miR-146a/mimic and plasmids were performed.Finally,C57BL/6J female mice were injected with mimic or miR-146a-overexpressing ESCs,and immunohistochemistry,Western blotting,and RT-qPCR assays were carried out on tissue samples from these mice.Results miR-146a was significantly upregulated during VSMC differentiation,accompanied with the VSMC-specific marker genes smooth muscle-alpha-actin(SMαA),smooth muscle 22(SM22),smooth muscle myosin heavy chain(SMMHC),and h1-calponin.Furthermore,overexpression of miR-146a enhanced the differentiation process in vitro and in vivo.Concurrently,the expression of Kruppel-like factor 4(KLF4),predicted as one of the top targets of miR-146a,was sharply decreased in miR-146a-overexpressing ESCs.Importantly,inhibiting KLF4 expression enhanced the VSMC-specific gene expression induced by miR-146a overexpression in differentiating ESCs.In addition,miR-146a upregulated the mRNA expression levels and transcriptional activity of VSMC differentiation-related transcription factors,including serum response factor(SRF)and myocyte enhancer factor 2c(MEF-2c).Conclusion Our data support that miR-146a promotes ESC-VSMC differentiation through regulating KLF4 and modulating the transcription factor activity of VSMCs.展开更多
Objective Hepatic stellate cells(HSCs)play a crucial role in liver fibrosis.Early-stage liver fibrosis is reversible and intimately associated with the state of HSCs.Kruppel-like factor 4(KLF4)plays a pivotal role in ...Objective Hepatic stellate cells(HSCs)play a crucial role in liver fibrosis.Early-stage liver fibrosis is reversible and intimately associated with the state of HSCs.Kruppel-like factor 4(KLF4)plays a pivotal role in a wide array of physiological and pathological processes.This study aimed to investigate the effect of KLF4 on the proliferation,apoptosis and phenotype of quiescent HSCs Methods We designed a KLF4 lentiviral vector and a KLF4 siRNA lentiviral vector,to upregulate and silence KLF4 expression in human HSC LX-2 cells via transfection.Cell proliferation was assessed using the CCK-8 assay.Flow cytometry was used to detect the cell cycle distribution and apoptosis rate.Western blotting was used to determine the levels of some quiescence and activation markers of HSCs Results Overexpression of KLF4 significantly increased the levels of E-cadherin and ZO-1,which are quiescent HSC markers,while significantly decreased the levels of N-cadherin and a-SMA,known activated HSC markers.In contrast,cell proliferation and apoptosis rates were elevated in LX-2 cells in which KLF4 expression was silenced Conclusion KLF4 inhibits the proliferation and activation of human LX-2 HSCs.It might be a key regulatory protein in the maintenance of HSC quiescence and may serve as a target for the inhibition of hepatic fibrosis.展开更多
Kruppel-like factor 4（Klf4） is a zinc finger transcription factor and plays crucial roles in Xenopus embryogenesis.However, its regulation during embryogenesis is still unclear. Here, we report that Tcf711, a key do...Kruppel-like factor 4（Klf4） is a zinc finger transcription factor and plays crucial roles in Xenopus embryogenesis.However, its regulation during embryogenesis is still unclear. Here, we report that Tcf711, a key downstream transducer of the Wnt signaling pathway, could promote Klf4 transcription and stimulate Klf4 promoter activity in early Xenopus embryos. Furthermore, cycloheximide treatment showed a direct effect on Klf4 transcription facilitated by Tcf711. Moreover, the dominant negative form of Tcf711（dnTcf711）, which lacks N-terminus of the β-catenin binding motif, could still activate Klf4 transcription, suggesting that this regulation is Wnt/β-catenin independent.Taken together, our results demonstrate that Tcf711 lies upstream of Klf4 to maintain its expression level during Xenopus embryogenesis.展开更多
目的:探讨体外沉默Kruppel样因子4(Kruppel like factor 4,KLF4)基因的表达对食管癌KYSE140细胞增殖及迁移的影响。方法:Western blotting法检测人食管癌细胞株KYSE140、KYSE150、EC109及EC9706及食管永生化细胞NE3中KLF4蛋白的表达,化...目的:探讨体外沉默Kruppel样因子4(Kruppel like factor 4,KLF4)基因的表达对食管癌KYSE140细胞增殖及迁移的影响。方法:Western blotting法检测人食管癌细胞株KYSE140、KYSE150、EC109及EC9706及食管永生化细胞NE3中KLF4蛋白的表达,化学合成2对靶向KLF4的siRNA(KLF4-siRNA1,KLF4-siRNA2),并设对照siRNA(Ctrl-siRNA),分别体外转染至高表达KLF4的食管癌KYSE140细胞中,形成KLF4-siRNA1-KYSE140、KLF4-siRNA2-KYSE140及Ctrl-siRNA-KYSE140细胞,通过MTT实验、Transwell实验分别检测转染后食管癌KYSE140细胞的增殖及迁移。结果:食管癌细胞株KYSE140中KLF4蛋白的表达明显高于KYSE150、EC109及EC9706细胞株[(5.62±0.02)vs(1.71±0.23)、(3.24±0.35)、(3.16±0.41),均P<0.05]。KLF4-siRNA1-KYSE140、KLF4-siRNA2-KYSE140与Ctrl-siRNA-KYSE140细胞相比,KLF4蛋白表达明显降低[(0.49±0.18)、(0.32±0.09)vs(0.98±0.19),均P<0.05],细胞增殖能力明显增高[(1.2±0.8)、(1.4±0.1)vs(0.6±0.1),均P<0.05],迁移细胞数量也明显增加[(780±22)、(475±25)vs(83±17)个,P<0.05]。结论:KLF4在人食管癌细胞的增殖和迁移过程中起着负调控作用。展开更多
Salidroside is extensively used as a herbal medicine worldwide, and it has been shown to protect against disruption of endothelial homeostasis and act as an anti-aging agent. The present study aimed to investigate the...Salidroside is extensively used as a herbal medicine worldwide, and it has been shown to protect against disruption of endothelial homeostasis and act as an anti-aging agent. The present study aimed to investigate the ameliorative effects of salidroside on homocysteine (Hcy)-induced cell senescence in human umbilical vein endothelial cells (HUVECs) that were mediated via inhibition of Krüppel-like factor 4 (KLF4). An endothelial cell senescence model was induced by Hcy. The cell viability, activities of telomerase and lactate dehydrogenase (LDH), and the level of reactive oxygen species were determined using commercial kits. The expression levels of KLF4, p53 and p21 were determined via western blot analysis, whereas the mRNA expression levels of KLF4 were detected by reverse transcription-quantitative PCR. Small interfering RNA-mediated knockdown of KLF4 was found to reverse Hcy-induced cell senescence. Hcy treatment led to an accelerated cell senescence, as evidenced by decreases in both cell viability and telomerase activity, whereas increases were noted in the leakage of LDH and the level of reactive oxygen species, in addition to an up-regulation of the protein levels of p53 and p21, and up-regulation of KLF4 at both the mRNA and protein level. Treatment with salidroside ameliorated Hcy-induced cell senescence in a dose-dependent manner. Taken together, these results suggested that Hcy may induce cell senescence through upregulation of KLF4, and this may be reversed by treatment with salidroside. Therefore, salidroside was shown to inhibit Hcy-induced cell senescence through KLF4 inhibition.展开更多
Objective: To study the correlation of KLF4 and UBE2C expression levels in neuroblastoma with cell adhesion and migration. Methods: A total of 56 children who were diagnosed with neuroblastoma in the Central Hospital ...Objective: To study the correlation of KLF4 and UBE2C expression levels in neuroblastoma with cell adhesion and migration. Methods: A total of 56 children who were diagnosed with neuroblastoma in the Central Hospital of Enshi Autonomous Prefecture between May 2014 and February 2017 were selected as the NB group of the study, and the lesion tissue was collected;38 children who were treated in the Central Hospital of Enshi Autonomous Prefecture due to serious hydronephrosis during the same period were selected as the control group of the study, and the normal adrenal gland tissue was collected. The mRNA expression and protein expression of KLF4 and UBE2C as well as the protein expression of cell adhesion molecules and migration molecules in clinical tissue samples were determined. Results: The mRNA expression and protein expression of KLF4 in neuroblastoma tissue of NB group were greatly lower than those of control group whereas the mRNA expression and protein expression of UBE2C were greatly higher than those of control group;PDLIM1, AMF, GPx1, L1CAM, Nrg1, RANK, RANKL, Inβ1, MTA1 and MMP9 protein expression in neuroblastoma tissue of NB group were greatly higher than those of control group, negatively correlated with the protein expression KLF4, and positively correlated with the protein expression of UBE2C. Conclusion: The low expression of KLF4 and the high expression of UBE2C in neuroblastoma can promote the adhesion and migration of tumor cells.展开更多
基金funded by the National Natural Science Foundation of China(No.82070376 and No.81873491)the Natural Science Foundation of Zhejiang Province(No.LY21H020005)+1 种基金the Zhejiang Medical Science and Technology Project(No.2019KY376 and No.2018KY071)a Ningbo Science and Technology Project(No.202002N3173).
文摘Objective Vascular smooth muscle cell(VSMC)differentiation from stem cells is one source of the increasing number of VSMCs that are involved in vascular remodeling-related diseases such as hypertension,atherosclerosis,and restenosis.MicroRNA-146a(miR-146a)has been proven to be involved in cell proliferation,migration,and tumor metabolism.However,little is known about the functional role of miR-146a in VSMC differentiation from embryonic stem cells(ESCs).This study aimed to determine the role of miR-146a in VSMC differentiation from ESCs.Methods Mouse ESCs were differentiated into VSMCs,and the cell extracts were analyzed by Western blotting and RT-qPCR.In addition,luciferase reporter assays using ESCs transfected with miR-146a/mimic and plasmids were performed.Finally,C57BL/6J female mice were injected with mimic or miR-146a-overexpressing ESCs,and immunohistochemistry,Western blotting,and RT-qPCR assays were carried out on tissue samples from these mice.Results miR-146a was significantly upregulated during VSMC differentiation,accompanied with the VSMC-specific marker genes smooth muscle-alpha-actin(SMαA),smooth muscle 22(SM22),smooth muscle myosin heavy chain(SMMHC),and h1-calponin.Furthermore,overexpression of miR-146a enhanced the differentiation process in vitro and in vivo.Concurrently,the expression of Kruppel-like factor 4(KLF4),predicted as one of the top targets of miR-146a,was sharply decreased in miR-146a-overexpressing ESCs.Importantly,inhibiting KLF4 expression enhanced the VSMC-specific gene expression induced by miR-146a overexpression in differentiating ESCs.In addition,miR-146a upregulated the mRNA expression levels and transcriptional activity of VSMC differentiation-related transcription factors,including serum response factor(SRF)and myocyte enhancer factor 2c(MEF-2c).Conclusion Our data support that miR-146a promotes ESC-VSMC differentiation through regulating KLF4 and modulating the transcription factor activity of VSMCs.
基金supported by the National Natural Science Foundation of China(No.81071541).
文摘Objective Hepatic stellate cells(HSCs)play a crucial role in liver fibrosis.Early-stage liver fibrosis is reversible and intimately associated with the state of HSCs.Kruppel-like factor 4(KLF4)plays a pivotal role in a wide array of physiological and pathological processes.This study aimed to investigate the effect of KLF4 on the proliferation,apoptosis and phenotype of quiescent HSCs Methods We designed a KLF4 lentiviral vector and a KLF4 siRNA lentiviral vector,to upregulate and silence KLF4 expression in human HSC LX-2 cells via transfection.Cell proliferation was assessed using the CCK-8 assay.Flow cytometry was used to detect the cell cycle distribution and apoptosis rate.Western blotting was used to determine the levels of some quiescence and activation markers of HSCs Results Overexpression of KLF4 significantly increased the levels of E-cadherin and ZO-1,which are quiescent HSC markers,while significantly decreased the levels of N-cadherin and a-SMA,known activated HSC markers.In contrast,cell proliferation and apoptosis rates were elevated in LX-2 cells in which KLF4 expression was silenced Conclusion KLF4 inhibits the proliferation and activation of human LX-2 HSCs.It might be a key regulatory protein in the maintenance of HSC quiescence and may serve as a target for the inhibition of hepatic fibrosis.
基金supported by the Start-up Funding of Henan University of Science and Technology(13480027) to Q. C.the Key Science Foundation of Nanjing Medical University(2015NJMUZD002)+2 种基金the Natural Science Foundation of Higher Education Institutions of Jiangsu Province(16KJB-180020)Natural Science Foundation of Jiangsu Province (BK20171053)National Natural Science Funds of China (81702747) to C.L
文摘Kruppel-like factor 4（Klf4） is a zinc finger transcription factor and plays crucial roles in Xenopus embryogenesis.However, its regulation during embryogenesis is still unclear. Here, we report that Tcf711, a key downstream transducer of the Wnt signaling pathway, could promote Klf4 transcription and stimulate Klf4 promoter activity in early Xenopus embryos. Furthermore, cycloheximide treatment showed a direct effect on Klf4 transcription facilitated by Tcf711. Moreover, the dominant negative form of Tcf711（dnTcf711）, which lacks N-terminus of the β-catenin binding motif, could still activate Klf4 transcription, suggesting that this regulation is Wnt/β-catenin independent.Taken together, our results demonstrate that Tcf711 lies upstream of Klf4 to maintain its expression level during Xenopus embryogenesis.
文摘目的:探讨体外沉默Kruppel样因子4(Kruppel like factor 4,KLF4)基因的表达对食管癌KYSE140细胞增殖及迁移的影响。方法:Western blotting法检测人食管癌细胞株KYSE140、KYSE150、EC109及EC9706及食管永生化细胞NE3中KLF4蛋白的表达,化学合成2对靶向KLF4的siRNA(KLF4-siRNA1,KLF4-siRNA2),并设对照siRNA(Ctrl-siRNA),分别体外转染至高表达KLF4的食管癌KYSE140细胞中,形成KLF4-siRNA1-KYSE140、KLF4-siRNA2-KYSE140及Ctrl-siRNA-KYSE140细胞,通过MTT实验、Transwell实验分别检测转染后食管癌KYSE140细胞的增殖及迁移。结果:食管癌细胞株KYSE140中KLF4蛋白的表达明显高于KYSE150、EC109及EC9706细胞株[(5.62±0.02)vs(1.71±0.23)、(3.24±0.35)、(3.16±0.41),均P<0.05]。KLF4-siRNA1-KYSE140、KLF4-siRNA2-KYSE140与Ctrl-siRNA-KYSE140细胞相比,KLF4蛋白表达明显降低[(0.49±0.18)、(0.32±0.09)vs(0.98±0.19),均P<0.05],细胞增殖能力明显增高[(1.2±0.8)、(1.4±0.1)vs(0.6±0.1),均P<0.05],迁移细胞数量也明显增加[(780±22)、(475±25)vs(83±17)个,P<0.05]。结论:KLF4在人食管癌细胞的增殖和迁移过程中起着负调控作用。
文摘Salidroside is extensively used as a herbal medicine worldwide, and it has been shown to protect against disruption of endothelial homeostasis and act as an anti-aging agent. The present study aimed to investigate the ameliorative effects of salidroside on homocysteine (Hcy)-induced cell senescence in human umbilical vein endothelial cells (HUVECs) that were mediated via inhibition of Krüppel-like factor 4 (KLF4). An endothelial cell senescence model was induced by Hcy. The cell viability, activities of telomerase and lactate dehydrogenase (LDH), and the level of reactive oxygen species were determined using commercial kits. The expression levels of KLF4, p53 and p21 were determined via western blot analysis, whereas the mRNA expression levels of KLF4 were detected by reverse transcription-quantitative PCR. Small interfering RNA-mediated knockdown of KLF4 was found to reverse Hcy-induced cell senescence. Hcy treatment led to an accelerated cell senescence, as evidenced by decreases in both cell viability and telomerase activity, whereas increases were noted in the leakage of LDH and the level of reactive oxygen species, in addition to an up-regulation of the protein levels of p53 and p21, and up-regulation of KLF4 at both the mRNA and protein level. Treatment with salidroside ameliorated Hcy-induced cell senescence in a dose-dependent manner. Taken together, these results suggested that Hcy may induce cell senescence through upregulation of KLF4, and this may be reversed by treatment with salidroside. Therefore, salidroside was shown to inhibit Hcy-induced cell senescence through KLF4 inhibition.
文摘Objective: To study the correlation of KLF4 and UBE2C expression levels in neuroblastoma with cell adhesion and migration. Methods: A total of 56 children who were diagnosed with neuroblastoma in the Central Hospital of Enshi Autonomous Prefecture between May 2014 and February 2017 were selected as the NB group of the study, and the lesion tissue was collected;38 children who were treated in the Central Hospital of Enshi Autonomous Prefecture due to serious hydronephrosis during the same period were selected as the control group of the study, and the normal adrenal gland tissue was collected. The mRNA expression and protein expression of KLF4 and UBE2C as well as the protein expression of cell adhesion molecules and migration molecules in clinical tissue samples were determined. Results: The mRNA expression and protein expression of KLF4 in neuroblastoma tissue of NB group were greatly lower than those of control group whereas the mRNA expression and protein expression of UBE2C were greatly higher than those of control group;PDLIM1, AMF, GPx1, L1CAM, Nrg1, RANK, RANKL, Inβ1, MTA1 and MMP9 protein expression in neuroblastoma tissue of NB group were greatly higher than those of control group, negatively correlated with the protein expression KLF4, and positively correlated with the protein expression of UBE2C. Conclusion: The low expression of KLF4 and the high expression of UBE2C in neuroblastoma can promote the adhesion and migration of tumor cells.
