miR-21 inhibitor suppresses proliferation and migration of nasopharyngeal carcinoma cells through down-regulation of BCL2 expression

This study is to investigate the expression of miR-21 in nasopharyngeal carcinoma (NPC) cells, and the effect of miR-21 in the biological behavior and expression of B-cell lymphoma 2 (BCL2) in NPC cells. Paired NPC and adjacent non-tumor tissues were obtained from 53 patients who underwent primary surgical resection of NPC tissues. Luciferase reporter assay was performed to test whether BCL2 is a direct target of miR-21. Methylthiazolyl blue tetrazolium assay and colony assay were used to evaluate the effect of miR-21 on NPC cell proliferation. Transwell and wound-healing assays were carried out to test the effect of low expression of miR-21 on cancer cell migration and invasion. QRT-PCR and Western blotting were used to measure the levels of mRNA and protein expression, respectively. Tumor tissues showed a positive correlation between the levels of miR-21 and BCL2 protein expression. Cells transfected with miR-21 inhibitor healed slower compared the control (P < 0.05). In addition, cell migration was notably inhibited by the down-regulation of miR-21 in vitro (P < 0.05). The reduction in miR-21 expression showed a remarkable effect on the biological behavior of NPC cell clone formation (P < 0.05). Low expression of miR-21 by transfection with miRNA expression plasmid led to a decrease in BCL2 expression, which was accompanied by reduced migration and proliferation of the cancer cells. Our results demonstrated that miR-21 inhibitor down-regulated BCL2 expression level, suggesting that BCL2 might be a target gene for the initiation and development of NPC cells.     

微小RNA在心肌重构中的作用

微小RNAs（miRNAs）是生物体中内源性的调控因子,它通过抑制相应mRNAs的翻译或降解特异mRNAs来调节特异基因的表达。新近研究发现miRNAs能调控心血管疾病的发生发展,如心肌肥厚、心脏纤维化、心律失常、心力衰竭等,参与了心肌的机械重构和电重构过程。随着对它的深入研究,发现人和动物心脏受损时血浆中某些miRNAs特异升高。以上发现使miRNAs有可能成为诊断心肌重构的生物标志物和治疗靶点。本文重点阐述miRNAs在心肌机械重构和电重构中的调控作用及其临床意义。     

Evaluation of SNPs in miR-196-a2, miR-27a and miR-146a as risk factors of colorectal cancer

AIM: To investigate whether selected single nucleotide polymorphisms (SNPs) in miR-196a2, miR-27a and miR-146a genes are associated with sporadic colorectal cancer (CRC).METHODS: In order to investigate the effect of these SNPs in CRC, we performed a case-control study of 197 cases of sporadic CRC and 212 cancer-free controls originating from the Central-European Caucasian population using TaqMan Real-Time polymerase chain reaction and allelic discrimination analysis.RESULTS: The genotype and allele frequencies of SNPs were compared between the cases and the controls. None of the performed analysis showed any statistically significant results.CONCLUSION: Our data suggest a lack of association between rs11614913, rs895819 and rs2910164 and colorectal cancer risk in the Central-European Caucasian population, a population with an extremely high incidence of sporadic colorectal cancer.     

MicroRNA在支气管哮喘中作用的研究进展

微小RNA(microRNA)是一类内源性的短链非编码小RNA,能与特定的信使RNA靶向结合,在转录后水平调控基因表达.MicroRNA可在人体许多生理和病理过程的多个环节发挥其调控作用.近年来的一些研究表明microRNA与支气管哮喘(简称哮喘)等气道炎症性疾病密切相关,下面就microRNA在哮喘中作用的研究进展作一综述,以使我们加深对哮喘发病机制的认识,更好地探索新的有效的治疗策略.     

microRNA介导的基因工程病毒减毒株研究进展

为了安全有效地进行基因治疗,需要把转染的基因限制在特定组织中表达。应用miRNA调节病毒基因表达是一个新方法。在miRNA介导的转基因表达系统中,可以将与miRNA互补的靶序列串联插入病毒基因3’非编码区域,导致在miRNA高表达细胞中抑制病毒的表达。我们总结了miRNA介导的病毒减毒株的应用。     

Relation of genetic polymorphisms in microRNAs with diastolic and systolic function in type 2 diabetes mellitus

Background and aimsType 2 diabetes mellitus (T2DM) has high risk of developing cardiac dysfunction, increasing of either cardiovascular death or hospitalization for heart failure. MicroRNAs (miRNA) affect cardiac function of T2DM. The aim of this study was to investigate the relationships between five miRNA single nucleotide polymorphisms (SNP) and diastolic and systolic function of T2DM.Methods and resultsThree hundred untreated T2DM subjects were included. Each subject underwent SNP genotyping, conventional echocardiography, tissue doppler imaging, and speckle tracking imaging. The effects of miRNA SNPs on diastolic and systolic function were evaluated. The diastolic function of T2DM subjects with miR-133a-1-rs8089787 wild genotype or let-7f-rs10877887 variant genotype was lower than those with miR-133a-1-rs8089787 variant genotype or let-7f-rs10877887 wild genotype, manifesting as higher left atrial volume index, lower mean E′, and higher E/E’ (P < 0.05). There were no significant effects of miR-133a-2-rs13040413, let-7a-1-rs13293512 and miR-27a-rs895819 on the diastolic function of T2DM subjects (P > 0.05). These five miRNA SNPs had no effect on the systolic function of T2DM subjects (P > 0.05).ConclusionsMiRNA-133a-1-rs8089787 and let-7f-rs10877887 were associated with impaired cardiac diastolic function in T2DM. The findings may be a promising therapeutic targets for preventing diastolic dysfunction in T2DM.