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101.
102.
Activated synovial fibroblasts in rheumatoid arthritis (RASF) play a critical role in the pathology of rheumatoid arthritis (RA). Recent studies suggested that deregulation of microRNAs (miRs) affects the development and progression of RA. Therefore, we aimed to identify de-regulated miRs in RASF and to identify target genes that may contribute to the aggressive phenotype of RASF. Quantitative real-time PCR revealed a marked downregulation of miR-188-5p in synovial tissue samples of RA patients as well as in RASF. Exposure to the cytokine interleukine-1β lead to a further downregulation of miR-188-5p expression levels compared to control cells. Re-expression of miR-188-5p in RASF by transient transfection significantly inhibited cell migration. However, miR-188-5p re-expression had no effects on glycosaminoglycan degradation or expression of repellent factors, which have been previously shown to affect the invasive behavior of RASF. In search for target genes of miR-188-5p in RASF we performed gene expression profiling in RASF and found a strong regulatory effect of miR-188-5p on the hyaluronan binding protein KIAA1199 as well as collagens COL1A1 and COL12A1, which was confirmed by qRT-PCR. In silico analysis revealed that KIAA1199 carries a 3’UTR binding site for miR-188-5p. COL1A1 and COL12A1 showed no binding site in the mRNA region, suggesting an indirect regulation of these two genes by miR-188-5p. In summary, our study showed that miR-188-5p is down-regulated in RA in vitro and in vivo, most likely triggered by an inflammatory environment. MiR-188-5p expression is correlated to the activation state of RASF and inhibits migration of these cells. Furthermore, miR-188-5p is directly and indirectly regulating the expression of genes, which may play a role in extracellular matrix formation and destruction in RA. Herewith, this study identified potential novel therapeutic targets to inhibit the development and progression of RA.  相似文献   
103.
Activated synovial fibroblasts in rheumatoid arthritis (RASF) play a critical role in the pathology of rheumatoid arthritis (RA). Recent studies suggested that deregulation of microRNAs (miRs) affects the development and progression of RA. Therefore, we aimed to identify de-regulated miRs in RASF and to identify target genes that may contribute to the aggressive phenotype of RASF. Quantitative real-time PCR revealed a marked downregulation of miR-188-5p in synovial tissue samples of RA patients as well as in RASF. Exposure to the cytokine interleukine-1β lead to a further downregulation of miR-188-5p expression levels compared to control cells. Re-expression of miR-188-5p in RASF by transient transfection significantly inhibited cell migration. However, miR-188-5p re-expression had no effects on glycosaminoglycan degradation or expression of repellent factors, which have been previously shown to affect the invasive behavior of RASF. In search for target genes of miR-188-5p in RASF we performed gene expression profiling in RASF and found a strong regulatory effect of miR-188-5p on the hyaluronan binding protein KIAA1199 as well as collagens COL1A1 and COL12A1, which was confirmed by qRT-PCR. In silico analysis revealed that KIAA1199 carries a 3’UTR binding site for miR-188-5p. COL1A1and COL12A1 showed no binding site in the mRNA region, suggesting an indirect regulation of these two genes by miR-188-5p. In summary, our study showed that miR-188-5p is down-regulated in RA in vitro and in vivo, most likely triggered by an inflammatory environment. MiR-188-5p expression is correlated to the activation state of RASF and inhibits migration of these cells. Furthermore, miR-188-5p is directly and indirectly regulating the expression of genes, which may play a role in extracellular matrix formation and destruction in RA. Herewith, this study identified potential novel therapeutic targets to inhibit the development and progression of RA.  相似文献   
104.
Emerging evidence showed that miRNA dysregulation is involved in the development of endometriosis and may contribute to pathological process of endometriosis associated ovarian cancer (EAOC). miR-191 is one of the most differentially expressed miRNAs in pairwise comparisons among healthy controls, endometriosis, and EAOC patients. However, its regulative network in endometriosis and EAOC are still not clear. This study explored the role of miR-191 in TNF-α induced cell death in ovarian endometriosis and endometrioid carcinoma cells. Based on tissues samples collected from healthy controls, endometriosis, and EAOC patients, this study verified significantly higher expression of miR-191 in endometriosis and endometrioid cancer. Interestingly, we also observed inverse expression trend between miR-191 and DAPK1, a positive mediator of programmed cell death. By conducting luciferase assay, we confirmed miR-191 can directly target DAPK1 and regulate its expression. Functionally, we also found DAPK1 can promote TNF-α induced cell death. DAPK1 knockdown in endometriosis CRL-7566 cells can weaken its response to TNF-α induced cell death, while its overexpression in endometrioid cancer cells CRL-11731 enhanced the response. These functions of DAPK1 can be directly modulated by miR-191. Therefore, the miR-191-DAPK1 axis may play an important role modulating the response of ovarian endometriosis and endometrioid carcinoma cells to death-inducers and might contribute malignant transformation of endometriosis.  相似文献   
105.
Epigenetic changes are correlated with tumor development showing aberrations in DNA methylation and histone modifications. To find the early changes, we evaluated the epigenetic events from early to late stage of the urethane induced lung tumor development in mouse model and tried to correlate the molecular events with the progression of tumor. We addressed the hypothesis by examining the tumor development, status of DNMTs, HDACs and MBDs, DNA methylation and expression of microRNA-29b during 1 to 36 weeks after urethane exposure that included the period before and after the tumor appearance. Tumors did not appear after 1 or 4 weeks but well defined tumors appeared after 12 weeks and larger tumors appeared at 36 weeks which was prevented by IP6. DNMT1, DNMT3a and DNMT3b were upregulated after urethane exposure at the time of no tumor till the tumor developed and showed its upregulated functional activity. DNMTs are shown to be the targets of microRNA-29b and we showed that microRNA-29b was downregulated in the line of DNMT upregulation. HDAC, the histone modifier, also showed progressive upregulation. Periodic increase in methyl binding proteins, MBD2, supported the expression of gene silencing pathways in terms of the downregulation of tumor suppressor genes, p16 and MLH1. All these molecular alterations were protected in the presence of IP6. Our results showed that the key steps of epigenetics, DNMTs, mir29b, and HDAC1, are altered both before and after the development of tumors.  相似文献   
106.
BACKGROUND Esophageal carcinoma is a malignant gastrointestinal tumor with a very poor prognosis.MicroRNA(miR)-1304 is a newly discovered non-coding RNA,which shows differential expression in other cancers,and its clinical value in esophageal carcinoma remains unclear.AIM To explore the expression of miR-1304 in patients with esophageal carcinoma and its clinical value.METHODS The expression of miR-1304 in patients with esophageal carcinoma was analyzed based on the data on miR in esophageal carcinoma downloaded from The Cancer Genome Atlas database.Quantitative real-time polymerase chain reaction was adopted to determine the expression of miR-1304 in the tissues and serum of patients.The clinical diagnostic value of miR-1304 and independent factors for recurrence and prognosis of esophageal carcinoma were then analyzed.The potential target genes of miR-1304 were predicted,and then analyzed based on gene ontology,Kyoto Encyclopedia of Genes,and Genomes,and protein-protein interaction.RESULTS The expression of miR-1304 in the tissues and serum of patients with esophageal carcinoma increased,and was also increased according to the database.Patients with high expression of miR-1304 suffered increased rates of tumor≥3 cm,low differentiation and stage II+III.miR-1304 had a diagnostic value in identifying esophageal carcinoma,tumor size,differentiation and TNM stage.Tumor size,differentiation,TNM stage,and miR-1304 were independent risk factors for recurrence of esophageal carcinoma,and they had certain predictive and diagnostic value for the recurrence of esophageal carcinoma.Seventy-eight patients showed a 3-year survival rate of 38.46%,and patients with high expression of miR-1304 had a relatively lower survival rate.Multivariate analysis revealed that tumor size,differentiation,recurrence and miR-1304 were independent factors for the prognosis of patients.MiRTarBase,miRDB,and Targetscan predicted 20 target genes in total.Gene ontology enrichment analysis found 18 functions with aP<0.05,and Kyoto Encyclopedia of Genes,and Genomes analysis found 11 signal pathways with aP<0.05.String analysis of protein co-expression found 269 relationship pairs,of which co-expression with epidermal growth factor was the most common.CONCLUSION miR-1304 can be used as a potential indicator for the diagnosis and recurrence of esophageal carcinoma and for survival of patients with this disease.  相似文献   
107.
目的检测胃癌患者血清中17种胃癌相关细胞因子的水平,研究其与miR-10b水平的相关性,筛选在实验诊断中对胃癌诊断有意义的肿瘤标志物并探讨其对胃癌诊断的应用价值。  相似文献   
108.
Objective miR-663 a has been reported to be downregulated by X-ray irradiation and participates in radiation-induced bystander effect via TGF-β1. The goal of this study was to explore the role of mi R-663 a during radiation-induced Epithelium-to-mesenchymal transition(EMT).Methods TGF-β1 or IR was used to induce EMT. After mi R-663 a transfection, cell migration and cell morphological changes were detected and the expression levels of mi R-663 a, TGF-β1, and EMT-related factors were quantified.R...  相似文献   
109.
ObjectiveMost acute promyelocytic leukemia cases are characterized by the PML-RARa fusion oncogene and low white cell counts in peripheral blood.MethodsBased on the frequent overexpression of miR-125-family miRNAs in acute promyelocytic leukemia, we examined the consequence of this phenomenon by using an inducible mouse model overexpressing human miR-125b.ResultsMiR-125b expression significantly accelerates PML-RARa-induced leukemogenesis, with the resultant induced leukemia being partially dependent on continued miR-125b overexpression. Interestingly, miR-125b expression led to low peripheral white cell counts to bone marrow blast percentage ratio, confirming the clinical observation in acute promyelocytic leukemia patients.ConclusionThis study suggests that dysregulated miR-125b expression is actively involved in disease progression and pathophysiology of acute promyelocytic leukemia, indicating that targeting miR-125b may represent a new therapeutic option for acute promyelocytic leukemia.  相似文献   
110.
目的探讨miR-363-5p靶向三结构域蛋白14(TRIM14)对3种乳腺癌细胞系凋亡的影响。 方法采用实时荧光定量PCR法比较不同化疗药物诱导3种乳腺癌细胞(MCF-7、MDA-MB-435、MCF-12A)中miR-363-5p和TRIM14 mRNA表达水平,采用免疫组化法检测不同亚型乳腺癌组织TRIM14表达情况。采用Western blotting检测TRIM14蛋白表达。采用流式细胞术检测细胞凋亡情况。应用生物信息学方法预测miR-363-5p与TRIM14的结合位点,通过干扰miR-363-5p和TRIM14研究miR-363-5p对3种乳腺癌细胞中TRIM14的调控作用。Pearson相关分析各亚型乳腺癌组织中miR-363-5p与TRIM14的相关性。 结果3种化疗药物均能促进细胞凋亡,化疗药物处理3种亚型乳腺癌细胞后miR-363-5p表达上升,TRIM14 mRNA表达下降。荧光素酶报告基因实验发现TRIM14是miR-363-5p的靶基因。过表达miR-363-5p后,3种亚型乳腺癌细胞凋亡率上升,TRIM14蛋白和mRNA下降。敲低TRIM14后3种亚型乳腺癌细胞凋亡率上升,过表达TRIM14后3种亚型乳腺癌细胞凋亡率下降。3种亚型乳腺癌组织miR-363-5p与TRIM14表达呈负相关。 结论化疗药物诱导3种亚型乳腺癌细胞后miR-363-5p表达上升,miR-363-5p靶向抑制TRIM14表达,促进3种乳腺癌细胞系凋亡。  相似文献   
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