An important factor in the emergence and progre sion of osteosarcoma(OS)is the dysregulated expression of microRNAs(miRNAs).Transcription factor 7-like 1(TCF7LI),a member of the T cell factor/lymphoid enhancer factor(...An important factor in the emergence and progre sion of osteosarcoma(OS)is the dysregulated expression of microRNAs(miRNAs).Transcription factor 7-like 1(TCF7LI),a member of the T cell factor/lymphoid enhancer factor(TCF/LEF)transcription factor family,interacts with the Wnt signaling pathway regulator β-catenin and acts as a DNA-specific binding protein.This study sought to elucidate the impact of the interaction between miR 3293p and TCF7L1 on.the growth and apoptosis of OS and analyze the regulatory expression relationship between miRNA and mRNA in osteosarcoma cells using a variety of approaches.MiR329-3p was significantly downregulated,while TCF7L1 was considerably up-regulated in all examined OS cell lines.Additionally,a clinical comparison study was performed using the TCGA database.Subsequently,the regulatory relationship between miR-329-3p and TCF7L1 on the proliferation and apoptosis of OS cells was verified through in vitro and in vivo experiments.When miR 329-3p was transfected into the OS cell line,the expression of TCF7L1 decreased,the proliferation of OS cells was inhibited,the cytoskeleton disintegrated,and the nucleus condensed to fom apoptotic bodies.The expression of proteins that indicate apoptosis increased simultaneously.The cell cycle was arrested in the G0/G1 phase,and the G1/S transition was blocked.The introduction of miR 3293p also inhibited downstream Cyclin D1 of the Wnt pathway.Xenograf experiments indicated that the overexpression of miR-329-3p signi ficanly inhibited the growth of OS xenografts in nude mice,and the expression of TCF7L1 and C-Myc in tumor tssues decreased.MiR 329-3p was significantly reduced in OS cells and played a suppressive role in tumorigenesis and proliferation by targeting TCF7L1 both in vitro and in vivo.Osteosarcoma cell cycle arrest and pathway inhibition were observed upon the regulation of TCF7LI by miR 3293p.Summarizing these results,it can be inferred that miR.3293p exerts anticancer efects in osteosarcoma by inhibiting TCF7L1.展开更多
Lin28A and Lin28B are homologous RNA-binding proteins that participate in the development of primordial germ cells. The mechanisms underlying expression and regulation of Lin28A have been well documented, but such inf...Lin28A and Lin28B are homologous RNA-binding proteins that participate in the development of primordial germ cells. The mechanisms underlying expression and regulation of Lin28A have been well documented, but such information for Lin28B is limited. In this study, a fragment of the Lin28B promoter was cloned, the pEGFP-pLin28B vector was constructed. DF-1 chicken fibroblasts were transfected and the expression of green fluorescent protein (GFP) was measured. Furtherly, Lin28B promoter of different lengths fragments was cloned using the chromosome-walking method and the fragments were ligated into the PGL3-Basic vector, and transfected into DF-1 cells. Results of dual-luciferase reporter assay showed that the core of the Lin28B promoter was included in the sequence from –1 431 to –1 034 bp. The binding sites of the transcription factor TCF7L2 was showed within this sequence by bioinformatics analysis. The promoter activity of Lin28B was downregulated (P<0.05) when the TCF7L2 binding site was mutated. Further experiments suggested that Lin28B promoter activity responded to the activation or inhibition of Wnt signaling. Results of chromatin immunoprecipitation and quantitative PCR showed that β-catenin-TCF7L2 may be enriched in the Lin28B promoter core area. In vivo and in vitro activation or inhibition of Wnt signaling significantly up- or down-regulated (P<0.05) Lin28B expression. H3K4me2 enriched in the promoter of Lin28B, which affected the regulation of Wnt signaling to Lin28B. In conclusion, our results showed that H3K4me2 and Wnt5a/β-catenin/TCF7L2 were the positive regulators of Lin28B expression. Findings of this study may lay a theoretical foundation for illuminating the mechanism underlying Lin28B expression.展开更多
AIM: To explore the association between TCF7L2 rs12255372 and rs7903146 single nucleotide polymorphisms(SNPs) and gastric cancer risk in Venezuelan patients.METHODS: We performed a case-control study including 122 par...AIM: To explore the association between TCF7L2 rs12255372 and rs7903146 single nucleotide polymorphisms(SNPs) and gastric cancer risk in Venezuelan patients.METHODS: We performed a case-control study including 122 paraffin-embedded archived intestinaltype gastric cancer samples and 129 biopsies obtained by superior endoscopy from chronic gastritis patients. Gastric cancer samples were classified according the degree of carcinoma differentiation. Genomic DNA was extracted from tissues, and the two SNPs of TCF7L2 gene(rs12255372 and rs7903146) were genotyped by polymerase chain reaction-restriction fragment length polymorphism reactions. Multiple regression analysis with adjustments for age and gender were performed and best-fitting models of inheritance were determined.RESULTS: After adjusting for age and sex the TCF7L2 rs7903146 TT genotype was associated with gastric cancer risk under the recessive genetic model(OR = 3.11, 95%CI: 1.22-7.92, P = 0.017). We further investigated the distribution of rs12255372 and rs7903146 genotypes according gastric cancer stratified by degree of differentiation, and we observed that carriers of rs7903146 T allele(CT + TT vs CC) had a significantly increased risk of moderate/well differentiated gastric cancer(dominant model, OR = 2.55, 95%CI: 1.35-4.80, P = 0.004), whereas the rs7903146 TT genotype was associated with poorly differentiated gastric cancer in the recessive model(OR = 3.65, 95%CI: 1.25-10.62, P = 0.018). We did not find association between rs12255372 SNP and the susceptibility of developing gastric cancer. CONCLUSION: TCF7L2 rs7903146 polymorphism is associated with gastric cancer risk in the Venezuelan population, and could be related to determine the degree of differentiation of tumor cells.展开更多
基金The Fund of National Cancer Center Research and Development(26-A-4),The Grants-in-Aid for Scientific Research(Grant Nos.15K10451,16K10866 and 16K20063)from Japan Society for the Promotion of Science.
文摘An important factor in the emergence and progre sion of osteosarcoma(OS)is the dysregulated expression of microRNAs(miRNAs).Transcription factor 7-like 1(TCF7LI),a member of the T cell factor/lymphoid enhancer factor(TCF/LEF)transcription factor family,interacts with the Wnt signaling pathway regulator β-catenin and acts as a DNA-specific binding protein.This study sought to elucidate the impact of the interaction between miR 3293p and TCF7L1 on.the growth and apoptosis of OS and analyze the regulatory expression relationship between miRNA and mRNA in osteosarcoma cells using a variety of approaches.MiR329-3p was significantly downregulated,while TCF7L1 was considerably up-regulated in all examined OS cell lines.Additionally,a clinical comparison study was performed using the TCGA database.Subsequently,the regulatory relationship between miR-329-3p and TCF7L1 on the proliferation and apoptosis of OS cells was verified through in vitro and in vivo experiments.When miR 329-3p was transfected into the OS cell line,the expression of TCF7L1 decreased,the proliferation of OS cells was inhibited,the cytoskeleton disintegrated,and the nucleus condensed to fom apoptotic bodies.The expression of proteins that indicate apoptosis increased simultaneously.The cell cycle was arrested in the G0/G1 phase,and the G1/S transition was blocked.The introduction of miR 3293p also inhibited downstream Cyclin D1 of the Wnt pathway.Xenograf experiments indicated that the overexpression of miR-329-3p signi ficanly inhibited the growth of OS xenografts in nude mice,and the expression of TCF7L1 and C-Myc in tumor tssues decreased.MiR 329-3p was significantly reduced in OS cells and played a suppressive role in tumorigenesis and proliferation by targeting TCF7L1 both in vitro and in vivo.Osteosarcoma cell cycle arrest and pathway inhibition were observed upon the regulation of TCF7LI by miR 3293p.Summarizing these results,it can be inferred that miR.3293p exerts anticancer efects in osteosarcoma by inhibiting TCF7L1.
基金We thank the Experimental Poultry Farm of the Poultry Institute,Chinese Academy of Agricultural Sciences,for providing experimental materialsThis work was supported by the Key Research and Development Program of China(2017YFE0108000)+1 种基金the National Natural Science Foundation of China(31872341,31572390)the High-Level Talent Support Program of Yangzhou University,China.
文摘Lin28A and Lin28B are homologous RNA-binding proteins that participate in the development of primordial germ cells. The mechanisms underlying expression and regulation of Lin28A have been well documented, but such information for Lin28B is limited. In this study, a fragment of the Lin28B promoter was cloned, the pEGFP-pLin28B vector was constructed. DF-1 chicken fibroblasts were transfected and the expression of green fluorescent protein (GFP) was measured. Furtherly, Lin28B promoter of different lengths fragments was cloned using the chromosome-walking method and the fragments were ligated into the PGL3-Basic vector, and transfected into DF-1 cells. Results of dual-luciferase reporter assay showed that the core of the Lin28B promoter was included in the sequence from –1 431 to –1 034 bp. The binding sites of the transcription factor TCF7L2 was showed within this sequence by bioinformatics analysis. The promoter activity of Lin28B was downregulated (P<0.05) when the TCF7L2 binding site was mutated. Further experiments suggested that Lin28B promoter activity responded to the activation or inhibition of Wnt signaling. Results of chromatin immunoprecipitation and quantitative PCR showed that β-catenin-TCF7L2 may be enriched in the Lin28B promoter core area. In vivo and in vitro activation or inhibition of Wnt signaling significantly up- or down-regulated (P<0.05) Lin28B expression. H3K4me2 enriched in the promoter of Lin28B, which affected the regulation of Wnt signaling to Lin28B. In conclusion, our results showed that H3K4me2 and Wnt5a/β-catenin/TCF7L2 were the positive regulators of Lin28B expression. Findings of this study may lay a theoretical foundation for illuminating the mechanism underlying Lin28B expression.
文摘AIM: To explore the association between TCF7L2 rs12255372 and rs7903146 single nucleotide polymorphisms(SNPs) and gastric cancer risk in Venezuelan patients.METHODS: We performed a case-control study including 122 paraffin-embedded archived intestinaltype gastric cancer samples and 129 biopsies obtained by superior endoscopy from chronic gastritis patients. Gastric cancer samples were classified according the degree of carcinoma differentiation. Genomic DNA was extracted from tissues, and the two SNPs of TCF7L2 gene(rs12255372 and rs7903146) were genotyped by polymerase chain reaction-restriction fragment length polymorphism reactions. Multiple regression analysis with adjustments for age and gender were performed and best-fitting models of inheritance were determined.RESULTS: After adjusting for age and sex the TCF7L2 rs7903146 TT genotype was associated with gastric cancer risk under the recessive genetic model(OR = 3.11, 95%CI: 1.22-7.92, P = 0.017). We further investigated the distribution of rs12255372 and rs7903146 genotypes according gastric cancer stratified by degree of differentiation, and we observed that carriers of rs7903146 T allele(CT + TT vs CC) had a significantly increased risk of moderate/well differentiated gastric cancer(dominant model, OR = 2.55, 95%CI: 1.35-4.80, P = 0.004), whereas the rs7903146 TT genotype was associated with poorly differentiated gastric cancer in the recessive model(OR = 3.65, 95%CI: 1.25-10.62, P = 0.018). We did not find association between rs12255372 SNP and the susceptibility of developing gastric cancer. CONCLUSION: TCF7L2 rs7903146 polymorphism is associated with gastric cancer risk in the Venezuelan population, and could be related to determine the degree of differentiation of tumor cells.
