LncRNA TUG1 alleviates cardiac hypertrophy by targeting miR-34a/DKK1/Wnt-β-catenin signalling

The current study was designed to explore the role and underlying mechanism of lncRNA taurine up-regulated gene 1 (TUG1) in cardiac hypertrophy. Mice were treated by transverse aortic constriction (TAC) surgery to induce cardiac hypertrophy, and cardiomyocytes were treated by phenylephrine (PE) to induce hypertrophic phenotype. Haematoxylin-eosin (HE), wheat germ agglutinin (WGA) and immunofluorescence (IF) were used to examine morphological alterations. Real-time PCR, Western blots and IF staining were used to detect the expression of RNAs and proteins. Luciferase assay and RNA pull-down assay were used to verify the interaction. It is revealed that TUG1 was up-regulated in the hearts of mice treated by TAC surgery and in PE-induced cardiomyocytes. Functionally, overexpression of TUG1 alleviated cardiac hypertrophy both in vivo and in vitro. Mechanically, TUG1 sponged and sequestered miR-34a to increase the Dickkopf 1 (DKK1) level, which eventually inhibited the activation of Wnt/β-catenin signalling. In conclusion, the current study reported the protective role and regulatory mechanism of TUG1 in cardiac hypertrophy and suggested that TUG1 may serve as a novel molecular target for treating cardiac hypertrophy.     

Methylation-mediated miR-214 regulates proliferation and drug sensitivity of renal cell carcinoma cells through targeting LIVIN

LIVIN, a member of the inhibitor of apoptosis proteins (IAPs), is reported playing important roles in the development and progression of multiple human cancers. However, its underlined mechanisms in human renal cell carcinoma (RCC) are still needed to be clarified. In the present study, we reported that inhibition of miR-214 promoted the expression of LIVIN, then facilitated RCC cells growth and reduced the sensitivity of RCC cells to chemotherapeutic drugs. In constant, overexpression of miR-214 had contradictory effects. Further investigation showed that miR-214 was down-regulated in RCC because of abnormal methylation. In addition, DNA methyltransferase DNMT1, miR-214 and LIVIN are directly correlated in RCC patients. In conclusion, these results suggest that abnormal miR-214 methylation negatively regulates LIVIN, which may promote RCC cells growth and reduced the sensitivity of RCC cells to chemotherapeutic drugs.     

miR-125b-5p促进分枝杆菌在宿主细胞和小鼠体内存活的研究

通过观察miR-125b-5p对分枝杆菌在宿主细胞和小鼠体内存活情况的影响,探究其在抗结核免疫过程中的作用。采用不同培养基对分枝杆菌进行培养并计数;以1640培养基加10%胎牛血清培养所有实验用细胞。将终浓度50 nmol/L的miR-125b-5p 模拟物、miR-125b-5p 抑制剂及磷酸盐缓冲液(PBS)对照加入细胞后,在不同时间点收集细胞。用分枝杆菌分别感染宿主细胞(A549、THP-1和RAW264.7)以及C57BL/6小鼠。采用定量聚合酶链反应检测miR-125b-5p的表达量。结果miR-125b-5p在分枝杆菌感染的多种宿主细胞及小鼠中都显著上调表达,其中小鼠肺部的表达量提高了约15倍。分别转染模拟物和抑制剂后,再用分枝杆菌感染细胞,结果发现miR-125b-5p可促进分枝杆菌在宿主细胞内的生长。当miR-125b-5p抑制剂注射到卡介苗(BCG)感染的小鼠体内时,小鼠体内的细菌载量显著降低(P<0.05)。本研究证明miR-125b-5p可调控分枝杆菌在宿主细胞及小鼠体内的生长,在抗结核免疫过程中发挥了重要作用。进一步对其作用机制的深入研究将为临床结核病的治疗提供理论指导。     

食道癌组织miR-21、miR-182表达与临床病理特征及预后的关系

目的:探讨食道癌组织微小RNA-21(miR-21)、微小RNA-182(miR-182)表达与临床病理特征及预后的关系。方法:选取2011年4月到2013年7月期间在我院接受手术治疗的食道癌患者84例,取患者的癌组织和癌旁正常组织作为检验标本,比较癌组织和癌旁正常组织中miR-21、mi R-182的表达水平,并分析食道癌组织中mi R-182、mi R-21的表达与临床病理特征及预后的关系。结果:癌组织中mi R-21、mi R-182的相对表达量明显高于癌旁正常组织,差异有统计学意义(P<0.05)。食道癌组织中mi R-21的表达与淋巴结转移、临床分期有关(P<0.05),与性别、年龄、分化程度、肿瘤大小无关(P>0.05);食道癌患者癌组织中miR-182的表达与年龄、性别、肿瘤大小无关(P>0.05),与分化程度、临床分期、淋巴结转移有关(P<0.05)。食道癌癌组织中miR-21、miR-182高表达患者的中位生存时间均低于低表达患者,差异有统计学意义(P<0.05)。结论:食道癌组织mi R-21、mi R-182表达与患者的部分临床病理特征及预后有关,两者有望成为食道癌新的治疗靶点。     

腔隙性脑梗死伴脑白质病变患者血清miR-146a和NSE水平与MoCA评分的关系研究

摘要 目的：研究腔隙性脑梗死（LI）伴脑白质病变（WML）患者血清miR-146a和神经元特异性烯纯化酶（NSE）水平与蒙特利尔认知评估量表（MoCA）评分的关系。方法：纳入我院从2017年3月～2019年3月收治的LI伴WML患者108例进行研究,记作LI伴WML组。另取同期收治的单纯WML患者与单纯LI患者各100例,分别记作WML组与LI组,再取同期于我院进行体检的健康人员100例作为对照组。比较四组人员的血清miR-146a和NSE水平、MoCA评分,并作相关性分析。结果：LI伴WML组、WML组、LI组血清miR-146a相对表达量均低于对照组,而LI伴WML组血清miR-146a相对表达量又显著低于WML组、LI组（均P＜0.05）;LI伴WML组、WML组、LI组血清NSE水平均显著高于对照组,且LI伴WML组血清NSE水平均显著高于WML组、LI组（均P＜0.05）。LI伴WML组MoCA总分显著低于WML组与LI组,且WML组与LI组MoCA总分显著低于对照组（均P＜0.05）。经Pearson相关性分析可得：LI伴WML组患者血清miR-146a相对表达量与MoCA总分呈正相关关系（P＜0.05）,而血清NSE水平与MoCA总分呈负相关关系（P＜0.05）。结论：LI伴WML患者的血清miR-146a水平存在明显低表达,而NSE水平存在明显高表达,并与MoCA评分相关,两者可能在认知功能损伤的发生、发展过程中起着至关重要的作用。     

Silencing LINC00504 inhibits cell proliferation,invasion as well as migration and promotes cell apoptosis in lung cancer cells via upregulating miR-876-3p

LINC00504 acts as an oncogene and associates with unfavorable prognosis in patients with lung cancer. Silencing LINC00504 may be a promising strategy for treatment of lung cancer and its effects were firstly investigated in lung cancer cells this study. The gene expression level of miR-876-3p as well as LINC00504 were measured via PCR assay. The cell proliferation was investigated through Cell Counting Kit-8 (CCK-8) assay and colony formation assay. Flow cytometry was applied for detection of cell apoptosis. Wound healing and transwell assay were performed for measurement of cell migration and invasion respectively. The apoptosis related protein expressions were measured by western blot. Luciferase report assay was conducted for verification the target gene. LINC00504 was higher expressed in five types of lung cancer cells studied herein when compared with the control normal cells. LINC00504 knockdown exerted inhibitory effects on cell apoptosis, cell migration as well as cell invasion and promoted cell apoptosis. All the effects mentioned above were counteracted by miR-876-3p inhibitor. Silencing LINC00504 possessed anti-proliferation, repression of cell invasion as well as migration and pro-apoptosis effects via targeting up-regulation of miR-876-3p in lung cancer cells, proving the new therapeutic targets and highlighting the potential application in future diagnosis and treatment in lung cancer.     

Downregulation of MiR-218 can alleviate high-glucose-induced renal proximal tubule injury by targeting GPRC5A

ABSTRACT

The purpose of this study was to explore the functional implication of microRNA-218 (miR-218) in diabetic nephropathy (DN) through high-glucose-stimulated renal proximal tubule impairment. Biological function experiments showed that miR-218 and inflammatory factors TNF-α and IL-1β were highly expressed in renal proximal tubule under high-glucose conditions. Inhibiting miR-218 alleviated renal tubular cell injury, which was represented by miR-218 inhibitor facilitating renal tubular cell vitality whilst reducing its apoptosis and levels of inflammation factors. In addition, we confirmed that miR-218 directly targeted GPRC5A and negatively regulated its expression. Co-transfection assay showed that overexpression of GPRC5A accentuated the mitigated action of miR-218 inhibitor on renal proximal tubule cell injury induced by high-glucose. Accordingly, these data indicated that downregulation of miR-218 can assuage high-glucose-resulted renal tubular cell damage, and its ameliorative effect was achieved by negative regulation of GPRC5A, which provides a novel direction for unearthing the pathogenesis and even further biological treatment of DN.     

乙型肝炎病毒X蛋白通过靶向miR-200c诱导DNA异常甲基化

乙型肝炎病毒x (hepatitis B virus x,HBx)蛋白是导致肝癌(hepatocellular Carcinoma,HCC)的重要因素.但HBX在HCC形成过程中表观遗传机制尚有待阐明.本研究发现microRNA-200c (miR-200c)在过表达乙型肝炎病毒的HCC中下调,并且其直接靶向DNA甲基转移酶3A (DNA methyltransferase 3A,DNMT3A).此外,miR-200c和DNMT3A在HB诱发的肝癌组织中呈现负相关.乙型肝炎病毒诱导miR-200c下调,进而引起DNMT3A表达上调,导致细胞中肿瘤相关基因的启动子超甲基化.我们对乙型肝炎病毒诱导的肝癌表观遗传学改变进行了进一步研究,并提出一种基于miRNA的靶向治疗乙型肝炎病毒相关肝癌的潜在方法.