乌索酸通过抑制miR-21表达诱导肝癌HepG2细胞凋亡的机制

探讨乌索酸通过调控miR-21表达从而诱导肝癌HepG2细胞凋亡的作用机制。采用MTT方法检测乌索酸对肝癌细胞增殖的抑制作用;qPCR检测肝癌细胞中miR-21的表达水平及乌索酸对HepG2细胞中miR-21表达的调控作用;转染miR-21 mimics进HepG2细胞中上调miR-21的表达后,MTT、流式细胞检测法、RT-PCR方法分别分析miR-21在乌索酸对细胞的增殖、凋亡以及对凋亡相关基因的调控过程中的作用。结果显示,与肝正常细胞L-02以及肝癌SMCC-7721、Bel-7402细胞相比较,乌索酸对肝癌HepG2细胞的增殖抑制效果最强,且HepG2细胞中miR-21的表达水平最高。乌索酸可下调HepG2细胞中miR-21的表达,且在24 h的下调作用最强。miR-21的表达上调可以部分抵消乌索酸对HepG2细胞的抑制增殖及促进凋亡,部分抵消下调凋亡抑制基因Bcl-2、survivin表达和上调促凋亡基因Bax表达的作用。结果提示,乌索酸通过抑制miR-21的表达诱导肝癌HepG2细胞凋亡。     

HBX在肝癌细胞中通过下调miR-199a增强AKT的表达

目的 探讨乙型肝炎病毒X蛋白(hepatitis B virus X protein,HBX)调节miR-199a的表达在HBV相关性肝癌发生中的分子机制.方法 重组HBX腺病毒(Ad-HBX)感染人肝癌HepG2细胞,HBX的siRNA转染稳定表达HBV基因的人肝癌HepG2.2.15细胞,荧光定量PCR方法检测HBV相关性肝癌组织标本和肝癌细胞中HBX、miR-199a、AKT的mRNA表达水平及运用Western blot检测肝癌组织标本和肝癌细胞中HBX、AKT的蛋白表达水平;分别用miR-199a mimics和miR-199a inhibitor的转染肝癌细胞后,荧光定量PCR方法检测肝癌细胞中AKT的mRNA表达水平及运用Westem blot检测肝癌细胞中AKT的蛋白表达水平.结果 miR-199a在HepG2.2.15细胞中表达水平显著低于HepG2细胞,并且证实其表达下调受到了HBX的调控(P＜0.05),HepG2.2.15细胞中AKT表达水平显著高于HepG2细胞(P＜0.05),在HepG2.2.15细胞中过表达miR-199a能明显下调AKT表达水平以及在HepG2细胞中抑制miR-199a能明显上调的AKT表达水平(P＜0.05),此外,miR-199a的表达量在HBV相关性肝癌组织比相应的癌旁组织表达降低.结论 HBX可以通过miR-199a调节AKT导致HBV相关性肝癌发生.     

MicroRNA-30a在评估慢性肾衰竭血液透析效果中的作用

目的 分析microRNA-30a (miR-30a)在慢性肾衰竭患者透析前后血清中的表达差异,评价其在评估慢性肾衰竭血液透析效果中的作用.方法 选取2012年10月至2013年12月本科收治的慢性肾衰竭患者40例,分别在患者透析前后采血并获得血清样本,采用mirVana PARIS Kit提取血清样本中总RNA,利用qRT-PCR法检测miR-30a的表达,临床生化检测患者透析前后血清中肌酐(Cr)、尿素氮(Ur)及β2微球蛋白(β2-MG)的含量,表达值行曼-惠特尼U检验,工作特征曲线(ROC curve)评估miR-30a在慢性肾衰竭患者透析效果中的价值.结果 miR-30a、Ur和β2-MG在慢性肾衰竭患者透析后的表达显著低于透析前(P＜0.05,P＜0.01),ROC curve显示在患者透析后miR-30a的表达低于透析前0.25倍以上时患者可获得较好的透析效果.结论 miR-30a可作为一种潜在的评估慢性肾衰竭血液透析效果的生物标志物.     

miR-185 acts as a tumor suppressor by targeting AKT1 in non-small cell lung cancer cells

Increasing evidence has shown that microRNAs play critical roles in the initiation and progression of non-small cell lung cancer (NSCLC). miR-185 is deregulated in various cancers, whereas its functional mechanism in NSCLC is still unclear. Here, we confirmed that the expression of miR-185 was significantly down-regulated in NSCLC tissues and cell lines. miR-185 over-expression caused significant suppression of in vitro cell proliferation, migration and invasion, and in vivo tumor growth. We subsequently identified that AKT1 was a target gene of miR-185. Re-expression of AKT1 could partially rescue the inhibitory effects of miR-185 on the capacity of NSCLC cell proliferation and motility. Collectively, we conclude that miR-185 has a critical function by blocking AKT1 in NSCLC cells, and it may be a novel therapeutic agent for miRNA based NSCLC therapy.     

High miR-196a and low miR-367 cooperatively correlate with unfavorable prognosis of high-grade glioma

Identification of microRNAs (miRNAs) could be beneficial for the diagnosis and prognosis of glioma. Therefore, we attempted to identify and develop specific miRNAs as prognostic and predictive markers for glioma patients. We compared the expression profiles of 365 miRNAs between 4 glioblastomas (GBMs, WHO grade IV) and 4 anaplastic astrocytomas (AAs, WHO grade III) using miRNA qPCR Array. MiR-196a (P = 0.004, fold change = 289.86) and miR-367 (P = 0.044, fold change = 0.03) were identified as the most up-regulated and down-regulated miRNAs in GBMs compared with AAs, respectively. We subsequently examined miR-196a and miR-367 expression levels in an independent series of 63 gliomas including 50 GBMs and 13 AAs, as well as 10 non-neoplastic brain tissues, and statistically analyzed the associations between miRNA expression and clinicopathological characteristics and survivals of these glioma patients. MiR-196a and miR-367 showed significant increased and decreased expression in high-grade gliomas relative to non-neoplastic brains, as well as in GBMs versus AAs, respectively. Additionally, high-miR-196a and low-miR-367 expression, alone or in combination, statistically correlated with aggressive clinicopathological features of gliomas. Furthermore, overall survivals of glioma patients with high-miR-196a, low-miR-367 and high-miR-196a/low-miR-367 expression tended to be shorter than the corresponding control groups (all P ≤ 0.001). Moreover, multivariate analysis indicated high-miR-196a/low-miR-367 as an independent prognostic indicator for glioma patients (P = 0.005, risk ratio = 1.8). Our results suggested that both high-miR-196a and low-miR-367 expression may be associated with aggressive progression and unfavorable clinical outcome in glioma patients. And combination of high-miR-196a and low-miR-367 expression may be a novel biomarker in identifying a poor prognosis group of high-grade glioma.     

MiR-218 inhibits HMGB1-mediated autophagy in endometrial carcinoma cells during chemotherapy

Endometrial carcinoma is the most common gynecological malignancy among women worldwide. Although treatment for EC has improved with the introduction of Paclitaxel (Tax) chemotherapy, the majority of patients will develop resistance to the treatment, leading to poor prognosis. One of the causes of chemoresistance is the increased ability to undergo autophagy. In this study, we identified that miR-218 was significantly down-regulated in Tax-resistant EC cells compared to the non-drug resistant cell lines, and overexpression of miR-218 sensitized paclitaxel resistant EC cells to paclitaxel. Moreover, we demonstrated that miR-218 directly binds to the 3’-UTR of HMGB1 gene. HMGB1 was upregulated in paclitaxel resistant EC cells, it mediated autophagy and contributed to chemotherapy resistance in endometrial carcinoma in vitro. HMGB1-mediated autophagy could be suppressed by miR-218 overexpression in Tax resistant EC cells. In summary, we determined the targeting role of miR-218 to HMGB1 and the regulation of miR-218 on the HMGB1-mediated cell autophagy during chemotherapy resistance in endometrial carcinoma cells. These results reveal novel potential role of miR-218 against chemotherapy resistance during the treatment of endometrial carcinoma.     

Decreased expression of miR-378 correlates with tumor invasiveness and poor prognosis of patients with glioma

microRNAs (miRNAs) are a class of small non-coding RNAs that play important roles in a variety of biological process. It has been reported that dysregulation of miRNA is always associated with cancer progression and development, and miR-378 aberrant expression has been found in some types of cancers. However, the association of miR-378 and glioma has not been evaluated. In this work, we measured the expression of miR-378 in glioma tissues and non-neoplastic brain tissues was measured using real-time PCR, and found that miRNA-378 expression level was significantly lower in glioma tissues compared with non-neoplastic brain tissues. Patients with lower miR-378 expression level had significantly poorer overall survival. Multivariate Cox regression analysis showed that miR-378 expression was an independent prognostic factor for 5-year overall survival. Over-expression of miR-378 inhibits glioma cell migration and invasion. In conclusion, our results indicated that miR-378 may serve as a tumor suppressor and play an important role in inhibiting tumor migration and invasion. Our work implicates the potential effect of miR-378 on the prognosis of glioma.     

miR-195 is a key negative regulator of hepatocellular carcinoma metastasis by targeting FGF2 and VEGFA

Hepatocellular carcinoma (HCC) is the most common primary tumor of liver and the fifth most common cancer in the world. Lung is the most frequent site for extra hepatic metastasis from hepatocellular carcinoma, while the cause and mechanism of it is still poor understood. Here, we identify that the expression of miR-195 is markedly impaired in the lung metastasis cell lines of HCC. The result of Real-time PCR reveals the expression of miR-195 is significantly downregulated in 92 HCC tissues. Low expression of miR-195 is associated with tumor size, portal vein thrombosis, TNM stage and patients survival. Luciferase reporter and ELISA assay prove that hematogenous metastasis related genes including FGF2 and VEGFA are the target genes of miR-195. Overexpression of miR-195 in HCC cell line BEL-7402 markedly inhibits the capability of migration and invasion. Taken together, our results suggest that miR-195, a tumor suppressor miRNA, contributes to the lung metastasis of HCC by negatively regulating FGF2 and VEGFA, providing key implications of miR-195 for the therapeutic intervention of HCC.     

Predictive role of miR-146a rs2910164 (C>G), miR-149 rs2292832 (T>C), miR-196a2 rs11614913 (T>C) and miR-499 rs3746444 (T>C) in the development of hepatocellular carcinoma

We conducted a case-control study to evaluate the association of miR-146a rs2910164 (C>G), miR-149 rs2292832 (T>C), miR-196a2 rs11614913 (T>C) and miR-499 rs3746444 (T>C) polymorphisms with the risk of hepatocellular carcinoma. A total of 274 patients with HCC were collected between January 2013 and December 2014. The polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was taken to determine the polymorphism of miR-146a C>G, miR-149 T>C, miR-196a2 T>C and miR-499 T>C. By comparing with control groups, patients with HCC were more likely to be males (OR=2.01, 95% CI=1.38-2.95), have older age (OR=1.52, 95% CI=1.09-2.13), have a history of alcohol drinking (OR=2.09, 95% CI=1.49-2.93), and be infected with HBV (OR=32.98, 95% CI=19.70-55.46) and HCV (OR=56.26, 95% CI=23.28-152.98) infection. By conditional regression analysis, individuals carrying the TC and CC genotypes of miR-196a2 T>C were found to be associated with an elevated risk of HCC compared to the TT genotype, and the adjusted odds ratio were 1.50 (1.03-2.17) and 2.86 (1.60-5.16), respectively. Moreover, the TC+CC genotype was correlated with an increased risk of HCC (OR=1.69, 95% CI=1.19-2.41) compared to the wide-type genotype. In conclusion, our results suggested that miR-196a2 T>C polymorphism is associated with HCC risk in Chinese population.     

Expression of miR-32 in human non-small cell lung cancer and its correlation with tumor progression and patient survival

Introduction: miR-32 has recently been found to be implicated in many critical processes in various types of human cancer. However, its clinical significance in human non-small cell lung cancer (NSCLC) has not yet been elucidated. In the present study, we investigated the expression of miR-32 in NSCLC and analyzed its association with clinical features and prognosis of NSCLC patients. Methods: Quantitative real-time PCR (qRT-PCR) was used to measure expression level of miR-32 in lung cancer cell lines, normal bronchial epithelial cells, 90 pairs of tumor samples and adjacent non-tumor tissues. To determine its prognostic value, overall survival was evaluated using the Kaplan-Meier method. Univariate and multivariate analysis were performed using the Cox proportional hazard analysis. Results: The expression of miR-32 was significantly decreased in lung cancer cell lines and NSCLC tissues compared with normal bronchial epithelial cells and adjacent non-tumor tissues (P < 0.05). This reduction of miR-32 was associated with tumor stage and lymph node metastasis (P < 0.05). Moreover, Kaplan-Meier analysis demonstrated that patients with low miR-32 expression had shorter overall survival time than those with high miR-32 expression (P < 0.05). Univariate analysis revealed statistically significant correlations between overall survival and miR-32 level, tumor stage and lymph node metastasis (P < 0.05). Furthermore, miR-32 levels, tumor stage and lymph node metastasis were independently associated with overall survival (P < 0.05). Conclusions: Our results provided the first evidence that down-regulation of miR-32 was correlated with NSCLC progression, and miR-32 might be a potential molecular biomarker for predicting the prognosis of patients.