Chronic inflammation plays a pivotal role in insulin resistance and type 2 diabetes,yet the mechanisms are not completely understood.Here,we demonstrated that serum LPS levels were significantly higher in newly diagno...Chronic inflammation plays a pivotal role in insulin resistance and type 2 diabetes,yet the mechanisms are not completely understood.Here,we demonstrated that serum LPS levels were significantly higher in newly diagnosed diabetic patients than in normal control.miR-145 level in peripheral blood mononuclear cells decreased in type 2 diabetics.LPS repressed the transcription of miR-143/145 cluster and decreased miR-145 levels.Attenuation of miR-145 activity by anti-miR-145 triggered liver inflammation and increased serum chemokines in C57BL/6 J mice.Conversely,lentivirus-mediated miR-145 overexpression inhibited macrophage infiltration,reduced body weight,and improved glucose metabolism in db/db mice.And miR-145 overexpression markedly reduced plaque size in the aorta in ApoE−/−mice.Both OPG and KLF5 were targets of miR-145.miR-145 repressed cell proliferation and induced apoptosis partially by targeting OPG and KLF5.miR-145 also suppressed NF-κB activation by targeting OPG and KLF5.Our findings provide an association of the environment with the progress of metabolic disorders.Increasing miR-145 may be a new potential therapeutic strategy in preventing and treating metabolic diseases such as type 2 diabetes and atherosclerosis.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
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
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
Viral myocarditis(VMC)is a cardiac disease associated with myocardial inflammation and injury induced by virus infection.Cardiomyocytes have recently been regarded as key players in eliciting and modulating inflammati...Viral myocarditis(VMC)is a cardiac disease associated with myocardial inflammation and injury induced by virus infection.Cardiomyocytes have recently been regarded as key players in eliciting and modulating inflammation within the myocardium.Kruppel-like factor 10(KLF10)is a crucial regulator of various pathological processes and plays different roles in a variety of diseases.However,its role in VMC induced by coxsackievirus B3(CVB3)infection remains unknown.In this study,we report that cardiac KLF10 confers enhanced protection against viral myocarditis.We found that KLF10 expression was downregulated upon CVB3 infection.KLF10 deficiency enhanced cardiac viral replication and aggravated VMC progress.Bone marrow chimera experiments indicated that KLF10 expression in nonhematopoietic cells was involved in the pathogenesis of VMC.We further identified MCP-1 as a novel target of KLF10 in cardiomyocytes,and KLF10 cooperated with histone deacetylase 1(HDAC1)to negatively regulate MCP-1 expression by binding its promoter,leading to activation of MCP-1 transcription and recruitment of Ly6C^(high) monocytes/macrophages into the myocardium.This novel mechanism of MCP-1 regulation by KLF10 might provide new insights into the pathogenesis of VMC and a potential therapeutic target for VMC.展开更多
Hydroxylated multi-walled carbon nanotubes(h-MWCNTs) and carboxylated MWCNTs(c-MWCNTs)have potential applications in biomedicine, but their toxicity to human endothelial cells under stressed conditions associated with...Hydroxylated multi-walled carbon nanotubes(h-MWCNTs) and carboxylated MWCNTs(c-MWCNTs)have potential applications in biomedicine, but their toxicity to human endothelial cells under stressed conditions associated with chronic diseases was less studied in vitro. This study stressed human umbilical vein endothelial cells(HUVECs) with ER stress inducer thapsigargin(TG), and investigated the toxicity of h-MWCNTs and c-MWCNTs to normal and stressed HUVECs. h-MWCNTs and c-MWCNTs modestly reduced cellular viability, significantly promoted soluble ICAM-1(sICAM-1),soluble VCAM-1(sVCAM-1) as well as intracellular ROS, and decreased the expression of transcription factor KLF2 and KLF4. Pre-treatment with TG significantly reduced cellular viability, promoted IL-6 and THP-1 monocyte adhesion, and increased the expression of a panel of ER stress genes. ANOVA indicated no interaction between MWCNTs and TG pre-treatment on most of the endpoints. It was concluded that the toxicity of h-MWCNTs and c-MWCNTs to HUVECs might not be exacerbated by ER stress展开更多
Kruppel-like factor 6 (KLF6) was reported as tumor suppressor in multiple cancers. However, loss of chromosomal locus spanning KLF6 is relatively infrequent in previous published studies. To explore the role of KLF6 i...Kruppel-like factor 6 (KLF6) was reported as tumor suppressor in multiple cancers. However, loss of chromosomal locus spanning KLF6 is relatively infrequent in previous published studies. To explore the role of KLF6 in hepatocellular carcinoma (HCC), we examined the gene for expression change, loss of heterozygosity (LOH) and mutation in 26 HCC samples. The expression levels of KLF6 were significantly down-regulated in HCCs, as detected by qRT-PCR. LOH occurred in 11 (52%) of 21 tumors, and all the samples with LOH showed KLF6 down-regulation. The mutational frequency was 24%, and sequence changes located in activation domain of KLF6. Furthermore, MTT assay showed a significant antiproliferative effect of the wt KLF6 transfected in HepG2 hepatoblastoma cells. Fluorescence-activated cell sorting analysis revealed that KLF6 could induce apoptosis. These findings indicate that deregulation of KLF6, together with genetic abnormalities of allelic imbalance and mutations, may play a role in HCC pathogenesis.展开更多
Our previous study has shown that the transcription factor Krüppel-like factor 7(KLF7) promotes peripheral nerve regeneration and motor function recovery after spinal cord injury.KLF7 also participates in traumat...Our previous study has shown that the transcription factor Krüppel-like factor 7(KLF7) promotes peripheral nerve regeneration and motor function recovery after spinal cord injury.KLF7 also participates in traumatic brain injury,but its regulatory mechanisms remain poorly understood.In the present study,an HT22 cell model of traumatic brain injury was established by stretch injury and oxygenglucose deprivation.These cells were then transfected with an adeno-associated virus carrying KLF7(AAV-KLF7).The results revealed that,after stretch injury and oxygen-glucose deprivation,KLF7 greatly reduced apoptosis,activated caspase-3 and lactate dehydrogenase,downregulated the expression of the apoptotic markers B-cell lymphoma 2(Bcl-2)-associated X protein(Bax) and cleaved caspase-3,and increased the expression of βIII-tubulin and the antiapoptotic marker Bcl-2.Furthermore,KLF7 overexpression upregulated Janus kinase 2(JAK2) and signal transducer and activator of transcription 3(STAT3) phosphorylation in HT22 cells treated by stretch injury and oxygenglucose deprivation.Immunoprecipitation assays revealed that KLF7 directly participated in the phosphorylation of STAT3.In addition,treatment with AG490,a selective inhibitor of JAK2/STAT3,weakened the protective effects of KLF7.A mouse controlled cortical impact model of traumatic brain injury was then established.At 30 minutes before modeling,AAV-KLF7 was injected into the ipsilateral lateral ventricle.The protein and m RNA levels of KLF7 in the hippocampus were increased at 1 day after injury and recovered to normal levels at 3 days after injury.KLF7 reduced ipsilateral hippocampal atrophy,decreased the injured cortex volume,downregulated Bax and cleaved caspase-3 expression,and increased the number of 5-bromo-2'-deoxyuridine-positive neurons and Bcl-2 protein expression.Moreover,KLF7 transfection greatly enhanced the phosphorylation of JAK2 and STAT3 in the ipsilateral hippocampus.These results suggest that KLF7 may protect hippocampal neurons after traumatic brain injur展开更多
Background:Considering the increase in the proportion of lung adenocarcinoma(LUAD)cases among all lung cancers and its considerable contribution to cancer-related deaths worldwide,we sought to identify novel oncogenes...Background:Considering the increase in the proportion of lung adenocarcinoma(LUAD)cases among all lung cancers and its considerable contribution to cancer-related deaths worldwide,we sought to identify novel oncogenes to provide potential targets and facilitate a better understanding of the malignant progression of LUAD.Methods:The results from the screening of transcriptome and survival analyses according to the integrated Gene Expression Omnibus(GEO)datasets and The Cancer Genome Atlas(TCGA)data were combined,and a promising risk biomarker called meiotic nuclear divisions 1(MND1)was selectively acquired.Cell viability assays and subcutaneous xenograftmodelswere used to validate the oncogenic role ofMND1 in LUADcell proliferation and tumor growth.Aseries of assays,including mass spectrometry,co-immunoprecipitation(Co-IP),and chromatin immunoprecipitation(ChIP),were performed to explore the underlying mechanism.Results:MND1 up-regulation was identified to be an independent risk factor for overall survival in LUAD patients evaluated by both tissue microarray staining and third party data analysis.In vivo and in vitro assays showed that MND1 promoted LUAD cell proliferation by regulating cell cycle.The results of the Co-IP,ChIP and dual-luciferase reporter assays validated that MND1 competitively bound to tumor suppressor Kruppel-like factor 6(KLF6),and thereby protecting E2F transcription factor 1(E2F1)from KLF6-induced transcriptional repression.Luciferase reporter and ChIP assays found that E2F1 activated MND1 transcription by binding to its promoter in a feedback manner.Conclusions:MND1,KLF6,and E2F1 form a positive feedback loop to regulate cell cycle and confer DDP resistance in LUAD.MND1 is crucial for malignant progression and may be a potential therapeutic target in LUAD patients.展开更多
Summary: To investigate the expression of KLF6mRNA in primary hepatocellular carcinoma (HCC), nomal liver tissues and the tissues adjacent to the cancers, reverse-transcription polymerase chain reaction (RT-PCR) was e...Summary: To investigate the expression of KLF6mRNA in primary hepatocellular carcinoma (HCC), nomal liver tissues and the tissues adjacent to the cancers, reverse-transcription polymerase chain reaction (RT-PCR) was employed to investigate the expression of the KLF6 gene in HCC, the corresponding adjacent non-cancerous tissues and normal liver tissue. Our results showed that an amplified fragment of 427 bp DNA was detected in 18 of 19 (94.7 %) adjacent non-cancerous tissues and normal liver tissue, and in 12 (85.7 %) of 14 HCC. There were no significant differences in the levels of KLF6 mRNA between normal liver and liver tumors (P>0.05). It is concluded that KLF6 mRNA is generally expressed in HCC.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
Although titanate nanofibers(TiNFs)and titanate nanotubes(TiNTs)have been proposed as relatively biocompatible nanomaterials(NMs),there is currently lacking of systemic studies which investigated the toxicity of TiNFs...Although titanate nanofibers(TiNFs)and titanate nanotubes(TiNTs)have been proposed as relatively biocompatible nanomaterials(NMs),there is currently lacking of systemic studies which investigated the toxicity of TiNFs and TiNTs to endothelium.In this study,we developed endothelial monolayer model by using cell culture inserts,and systemically investigated the toxicity of TiNFs and TiNTs by RNA-seq,with a focus on Kruppel-like factor(KLF)-mediated effects,since KLF are transcription factors(TF)involved in the regulation of vascular biology.It was shown that NMs did not significantly induce cytotoxicity despite substantial internalization.However,the expression of many KLF was altered,and Western blot further confirmed that NMs down-regulated KLF2 proteins.Ingenuity pathway analysis(IPA)revealed that NMs altered the expression of KLF2-targed genes,typically the genes involved in inflammatory responses.KLF2-related Gene Ontology(GO)terms and Kyoto Encyclopedia of Gene and Genomes(KEGG)pathways were also altered,and it should be noticed that NMs altered GO terms and KEGG pathways related with endothelial NO synthase(eNOS).This study further verified that NMs decreased intracellular NO and eNOS proteins.All the observed effects were more obvious for TiNFs compared with TiNTs.Combined,this study showed that TiNFs or TiNTs we re non-cytotoxic to endothelial monolayer model,but TiNFs and more modestly TiNTs decreased KLF2 leading to decreased eNOS proteins and NO production.Our data may provide novel understanding about the toxicity of TiNFs as well as other Ti-based NMs to endothelium.展开更多
基金This work was supported by grants from the National Natural Science Foundation of China(81270902,81381220308,and 30230380).
文摘Chronic inflammation plays a pivotal role in insulin resistance and type 2 diabetes,yet the mechanisms are not completely understood.Here,we demonstrated that serum LPS levels were significantly higher in newly diagnosed diabetic patients than in normal control.miR-145 level in peripheral blood mononuclear cells decreased in type 2 diabetics.LPS repressed the transcription of miR-143/145 cluster and decreased miR-145 levels.Attenuation of miR-145 activity by anti-miR-145 triggered liver inflammation and increased serum chemokines in C57BL/6 J mice.Conversely,lentivirus-mediated miR-145 overexpression inhibited macrophage infiltration,reduced body weight,and improved glucose metabolism in db/db mice.And miR-145 overexpression markedly reduced plaque size in the aorta in ApoE−/−mice.Both OPG and KLF5 were targets of miR-145.miR-145 repressed cell proliferation and induced apoptosis partially by targeting OPG and KLF5.miR-145 also suppressed NF-κB activation by targeting OPG and KLF5.Our findings provide an association of the environment with the progress of metabolic disorders.Increasing miR-145 may be a new potential therapeutic strategy in preventing and treating metabolic diseases such as type 2 diabetes and atherosclerosis.
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.
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This work was supported by the Chinese National Natural Science Foundation(31400769,31870903,31870868,and 31670930)Jiangsu Province Natural Science Foundation(BK20140371)+1 种基金Jiangsu Postdoctoral Science Foundation(1402176C)Priority Academic Program Development of Jiangsu Higher Education Institutions.
文摘Viral myocarditis(VMC)is a cardiac disease associated with myocardial inflammation and injury induced by virus infection.Cardiomyocytes have recently been regarded as key players in eliciting and modulating inflammation within the myocardium.Kruppel-like factor 10(KLF10)is a crucial regulator of various pathological processes and plays different roles in a variety of diseases.However,its role in VMC induced by coxsackievirus B3(CVB3)infection remains unknown.In this study,we report that cardiac KLF10 confers enhanced protection against viral myocarditis.We found that KLF10 expression was downregulated upon CVB3 infection.KLF10 deficiency enhanced cardiac viral replication and aggravated VMC progress.Bone marrow chimera experiments indicated that KLF10 expression in nonhematopoietic cells was involved in the pathogenesis of VMC.We further identified MCP-1 as a novel target of KLF10 in cardiomyocytes,and KLF10 cooperated with histone deacetylase 1(HDAC1)to negatively regulate MCP-1 expression by binding its promoter,leading to activation of MCP-1 transcription and recruitment of Ly6C^(high) monocytes/macrophages into the myocardium.This novel mechanism of MCP-1 regulation by KLF10 might provide new insights into the pathogenesis of VMC and a potential therapeutic target for VMC.
基金financially supported by College Outstanding Young and Middle-aged Innovative Research Team Project of HubeiProvince (No. T201717)the Health and Family Planning Commission Scientific Research Project of Hubei Province (No. WJ2017Z027)
文摘Hydroxylated multi-walled carbon nanotubes(h-MWCNTs) and carboxylated MWCNTs(c-MWCNTs)have potential applications in biomedicine, but their toxicity to human endothelial cells under stressed conditions associated with chronic diseases was less studied in vitro. This study stressed human umbilical vein endothelial cells(HUVECs) with ER stress inducer thapsigargin(TG), and investigated the toxicity of h-MWCNTs and c-MWCNTs to normal and stressed HUVECs. h-MWCNTs and c-MWCNTs modestly reduced cellular viability, significantly promoted soluble ICAM-1(sICAM-1),soluble VCAM-1(sVCAM-1) as well as intracellular ROS, and decreased the expression of transcription factor KLF2 and KLF4. Pre-treatment with TG significantly reduced cellular viability, promoted IL-6 and THP-1 monocyte adhesion, and increased the expression of a panel of ER stress genes. ANOVA indicated no interaction between MWCNTs and TG pre-treatment on most of the endpoints. It was concluded that the toxicity of h-MWCNTs and c-MWCNTs to HUVECs might not be exacerbated by ER stress
文摘Kruppel-like factor 6 (KLF6) was reported as tumor suppressor in multiple cancers. However, loss of chromosomal locus spanning KLF6 is relatively infrequent in previous published studies. To explore the role of KLF6 in hepatocellular carcinoma (HCC), we examined the gene for expression change, loss of heterozygosity (LOH) and mutation in 26 HCC samples. The expression levels of KLF6 were significantly down-regulated in HCCs, as detected by qRT-PCR. LOH occurred in 11 (52%) of 21 tumors, and all the samples with LOH showed KLF6 down-regulation. The mutational frequency was 24%, and sequence changes located in activation domain of KLF6. Furthermore, MTT assay showed a significant antiproliferative effect of the wt KLF6 transfected in HepG2 hepatoblastoma cells. Fluorescence-activated cell sorting analysis revealed that KLF6 could induce apoptosis. These findings indicate that deregulation of KLF6, together with genetic abnormalities of allelic imbalance and mutations, may play a role in HCC pathogenesis.
基金supported by the National Natural Science Foundation of China,No.81870977 (to YW)the Natural Science Foundation of Heilongjiang of China,No.H2018068 (to WYL)+3 种基金the Basic Research Operating Expenses Program of Heilongjiang Provincial Universities of China,No.2019-KYYWFMY-0018 (to WYL)the Graduate Innovative Research Projects of Mudanjiang Medical College of China,No.YJSCX-MY22 (to DM)Key projects of Education Department of Hebei Province of China,No.ZD2020178 (to XMF)Hebei Key Laboratory of Nerve Injury and Repair of China (to XMF)。
文摘Our previous study has shown that the transcription factor Krüppel-like factor 7(KLF7) promotes peripheral nerve regeneration and motor function recovery after spinal cord injury.KLF7 also participates in traumatic brain injury,but its regulatory mechanisms remain poorly understood.In the present study,an HT22 cell model of traumatic brain injury was established by stretch injury and oxygenglucose deprivation.These cells were then transfected with an adeno-associated virus carrying KLF7(AAV-KLF7).The results revealed that,after stretch injury and oxygen-glucose deprivation,KLF7 greatly reduced apoptosis,activated caspase-3 and lactate dehydrogenase,downregulated the expression of the apoptotic markers B-cell lymphoma 2(Bcl-2)-associated X protein(Bax) and cleaved caspase-3,and increased the expression of βIII-tubulin and the antiapoptotic marker Bcl-2.Furthermore,KLF7 overexpression upregulated Janus kinase 2(JAK2) and signal transducer and activator of transcription 3(STAT3) phosphorylation in HT22 cells treated by stretch injury and oxygenglucose deprivation.Immunoprecipitation assays revealed that KLF7 directly participated in the phosphorylation of STAT3.In addition,treatment with AG490,a selective inhibitor of JAK2/STAT3,weakened the protective effects of KLF7.A mouse controlled cortical impact model of traumatic brain injury was then established.At 30 minutes before modeling,AAV-KLF7 was injected into the ipsilateral lateral ventricle.The protein and m RNA levels of KLF7 in the hippocampus were increased at 1 day after injury and recovered to normal levels at 3 days after injury.KLF7 reduced ipsilateral hippocampal atrophy,decreased the injured cortex volume,downregulated Bax and cleaved caspase-3 expression,and increased the number of 5-bromo-2'-deoxyuridine-positive neurons and Bcl-2 protein expression.Moreover,KLF7 transfection greatly enhanced the phosphorylation of JAK2 and STAT3 in the ipsilateral hippocampus.These results suggest that KLF7 may protect hippocampal neurons after traumatic brain injur
基金Project of Jiangsu Provincial Medical Talent,Grant/Award Number:ZDRCA2016033China Postdoctoral Science Foundation,Grant/Award Number:2018M640465+2 种基金National Natural Science Foundation of China,Grant/Award Numbers:81672295,81702265,81802277,81872378Research Program of Jiangsu Health Department,Grant/Award Number:LGY2016025Social Development Project of Jiangsu Province,Grant/Award Number:BE2019758。
文摘Background:Considering the increase in the proportion of lung adenocarcinoma(LUAD)cases among all lung cancers and its considerable contribution to cancer-related deaths worldwide,we sought to identify novel oncogenes to provide potential targets and facilitate a better understanding of the malignant progression of LUAD.Methods:The results from the screening of transcriptome and survival analyses according to the integrated Gene Expression Omnibus(GEO)datasets and The Cancer Genome Atlas(TCGA)data were combined,and a promising risk biomarker called meiotic nuclear divisions 1(MND1)was selectively acquired.Cell viability assays and subcutaneous xenograftmodelswere used to validate the oncogenic role ofMND1 in LUADcell proliferation and tumor growth.Aseries of assays,including mass spectrometry,co-immunoprecipitation(Co-IP),and chromatin immunoprecipitation(ChIP),were performed to explore the underlying mechanism.Results:MND1 up-regulation was identified to be an independent risk factor for overall survival in LUAD patients evaluated by both tissue microarray staining and third party data analysis.In vivo and in vitro assays showed that MND1 promoted LUAD cell proliferation by regulating cell cycle.The results of the Co-IP,ChIP and dual-luciferase reporter assays validated that MND1 competitively bound to tumor suppressor Kruppel-like factor 6(KLF6),and thereby protecting E2F transcription factor 1(E2F1)from KLF6-induced transcriptional repression.Luciferase reporter and ChIP assays found that E2F1 activated MND1 transcription by binding to its promoter in a feedback manner.Conclusions:MND1,KLF6,and E2F1 form a positive feedback loop to regulate cell cycle and confer DDP resistance in LUAD.MND1 is crucial for malignant progression and may be a potential therapeutic target in LUAD patients.
文摘Summary: To investigate the expression of KLF6mRNA in primary hepatocellular carcinoma (HCC), nomal liver tissues and the tissues adjacent to the cancers, reverse-transcription polymerase chain reaction (RT-PCR) was employed to investigate the expression of the KLF6 gene in HCC, the corresponding adjacent non-cancerous tissues and normal liver tissue. Our results showed that an amplified fragment of 427 bp DNA was detected in 18 of 19 (94.7 %) adjacent non-cancerous tissues and normal liver tissue, and in 12 (85.7 %) of 14 HCC. There were no significant differences in the levels of KLF6 mRNA between normal liver and liver tumors (P>0.05). It is concluded that KLF6 mRNA is generally expressed in HCC.
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.
基金financially supported by Hunan Innovative Province Construction Special Major Landmark Innovation Demonstration Project(No.2019XK2303)Xiangtan Science and Technology Project(No.ZD-ZD20191007)。
文摘Although titanate nanofibers(TiNFs)and titanate nanotubes(TiNTs)have been proposed as relatively biocompatible nanomaterials(NMs),there is currently lacking of systemic studies which investigated the toxicity of TiNFs and TiNTs to endothelium.In this study,we developed endothelial monolayer model by using cell culture inserts,and systemically investigated the toxicity of TiNFs and TiNTs by RNA-seq,with a focus on Kruppel-like factor(KLF)-mediated effects,since KLF are transcription factors(TF)involved in the regulation of vascular biology.It was shown that NMs did not significantly induce cytotoxicity despite substantial internalization.However,the expression of many KLF was altered,and Western blot further confirmed that NMs down-regulated KLF2 proteins.Ingenuity pathway analysis(IPA)revealed that NMs altered the expression of KLF2-targed genes,typically the genes involved in inflammatory responses.KLF2-related Gene Ontology(GO)terms and Kyoto Encyclopedia of Gene and Genomes(KEGG)pathways were also altered,and it should be noticed that NMs altered GO terms and KEGG pathways related with endothelial NO synthase(eNOS).This study further verified that NMs decreased intracellular NO and eNOS proteins.All the observed effects were more obvious for TiNFs compared with TiNTs.Combined,this study showed that TiNFs or TiNTs we re non-cytotoxic to endothelial monolayer model,but TiNFs and more modestly TiNTs decreased KLF2 leading to decreased eNOS proteins and NO production.Our data may provide novel understanding about the toxicity of TiNFs as well as other Ti-based NMs to endothelium.