头颈部鳞状细胞癌预后相关的miRNAs的生物信息学分析

目的 利用癌症基因组图谱（TCGA）数据库微小核糖核酸（miRNAs）表达谱数据分析头颈部鳞状细胞癌（HNSCC）与癌旁正常组织间差异表达的miRNAs,结合临床信息寻找与HNSCC预后相关的miRNAs。方法 从TCGA中下载miRNAs表达数据,包括39例HNSCC患者和39个肿瘤邻近正常组织样本筛选差异表达的miRNAs,应用481例HNSCC患者的miRNAs表达谱和临床信息来评估找到的差异表达miRNAs的预后作用。结果 共筛选出114个差异表达的miRNAs,包括60个上调和54个下调的miRNAs。Kaplan-Meier生存分析显示miR-4652-5p和miR-99a-3p与HNSCC患者预后相关,单因素和多因素Cox回归分析显示,miR-4652-5p和miR-99a-3p是HNSCC的重要预后因素。结论 miR-4652-5p和miR-99a-3p与HNSCC患者预后相关,但miR-4652-5p和miR-99a-3p在头颈鳞状细胞癌发生发展中的分子机制仍需更全面的基础和临床研究进行探讨。     

Expression profiling of micro-RNAs in human esophageal squamous cell carcinoma using RT-PCR

To develop novel therapeutic and diagnostic methods for esophageal cancer, it is important to understand the precise biological mechanism. Micro-RNAs (miRNAs) seem to be crucial factors in diverse regulation pathways. In this study, we analyzed the expression of mature miRNAs in esophageal squamous cell carcinoma (ESCC). The expression of 73 miRNAs was quantified by qRT-PCR in 30 primary ESCC specimens. We examined the correlation between miRNA expressions and the clinicopathological factors and prognosis of ESCC. The Kaplan-Meier survival curves showed that the high expression levels of 6 of the 72 miRNAs correlated with significantly lower patient survival rates. The overexpression of miR-129 was identified as a significant and independent prognostic factor (P = 0.031) in surgically treated ESCC patients. The hazard ratio for the prediction of early death was 18.11 for high versus low expression levels of miR-129. Similar results were obtained from an analysis performed on an additional 19 patients (test cohort) (P = 0.0057, for training cohort; P = 0.011, for test cohort; log-rank test). This experiment supports the notion that the high miR-129 expression levels, as observed in this study, might play a important role in the development of esophageal cancer.     

Increased expression of microRNA-196a predicts poor prognosis in human ovarian carcinoma

Objective: Overexpression of MicroRNA-196a (miR-196a) has recently been reported in different types of human cancers. However, the prognostic value of miR-196a in ovarian carcinoma remains unknown. In this study, we investigated the expression of miR-196a in ovarian carcinoma and its relationship with tumor progression and clinical prognosis. Methods: The expression level of miR-196a was examined by quantitative Real-time PCR (qRT-PCR) in surgically removed ovarian cancer tissues and ovarian cancer cell lines. The correlation between miR-196a expression and clinical features and prognosis were statistically analyzed. Results: The results showed that the miR-196a expression was significantly upregulated in tumor tissues and ovarian cancer cell lines compared with that in normal ovarian surface tissues and normal ovarian epithelial cells. Moreover, miR-196a expression was positively correlated with FIGO stage (P <0.001), tumor size (P =0.020), and lymph nodes metastasis (P =0.019). Kaplan-Meier analysis demonstrated that high levels of miR-196a expression was associated with poorer overall survival (P <0.001) and recurrent-free survival (P =0.003), especially in patients with advanced disease (P =0.002). Multivariate analysis suggested that miR-196a expression was an independent prognostic factor for overall survival of patients with ovarian carcinoma. Conclusions: In conclusion, miR-196a may play an important role in the progression of ovarian carcinoma, and could be used as an independent prognostic biomarker for patients with ovarian carcinoma.     

子宫颈癌中miR-153和Survivin的表达及其临床意义

目的探讨miR-153和Survivin在子宫颈癌组织中的表达及其对子宫颈癌的临床意义。方法收集50例子宫颈癌和40例正常子宫颈组织,采用RT-PCR法和免疫组化SP法检测miR-153和Survivin在子宫颈癌和正常子宫颈组织中的表达,分析两者表达与子宫颈癌临床病理特征的关系及对患者预后的意义。结果miR-153在子宫颈癌组织中的相对表达量低于正常子宫颈组织,Survivin在子宫颈癌组织中的相对表达量高于正常子宫颈组织,差异均有统计学意义(t=16.333,t=6.407,P<0.01)。通过散点图及相关性分析,在子宫颈癌组织中miR-153和Survivin相对表达量呈负相关,差异有统计学意义(P<0.01);miR-153、Survivin表达与患者年龄、肿瘤大小、TNM分期均无关(P>0.05),与淋巴结转移明显相关(χ^2=6.455,χ^2=5.937,P<0.05)。通过散点图及相关性分析,淋巴结转移患者的淋巴结受侵数目与miR-153表达量呈负相关,与Survivin表达量呈正相关,差异均有统计学意义(P<0.01)。预后生存分析发现,miR-153高表达患者生存率高于低表达患者,Survivin高表达患者生存率低于低表达患者,差异均有统计学意义(χ^2=19.390,χ^2=27.921,P<0.01)。结论miR-153在子宫颈癌组织中低表达,与Survivin在子宫颈癌组织中表达水平呈负相关,可能与子宫颈癌的增殖、侵袭转移有关。     

Identification of miR-375 as a potential prognostic biomarker for esophageal squamous cell cancer: A bioinformatics analysis based on TCGA and meta-analysis

Accumulating evidence has demonstrated that aberrantly expressed miRNAs in cancer tissues regulated various cellular processes related to carcinogenesis. The present study aimed to identify the differentially expressed miRNAs between esophageal squamous cell cancer (ESCC) and adjacent normal esophageal tissue (ANET). In our present study, we identified 129 differentially expressed miRNAs between ESCC and ANET by analyzing high-throughput miRNA data downloaded from TCGA database. After investigating the prognostic value of the 129 differential expressed miRNAs, eight miRNAs were found to be associated with prognosis of patients with ESCC. The clinical significance and bio-function of miR-375 was further examined. We performed Gene Set Enrichment Analysis (GSEA) to identify the top three gene sets that significantly altered between the patients with miR-375 low expression and high expression. In order to explore the mechanism of the development and progression of ESCC, the role of miR-375 in ESCC and its four candidate target genes was examined. At last, we performed a meta-analysis to verify the prognostic value of miR-375 in ESCC. In conclusion, our findings suggest that miR-375 serves as a promising independent prognostic factor for ESCC and function as a tumor suppressor.     

Decreased expression of serum miR-424 correlates with poor prognosis of patients with hepatocellular carcinoma

Background: MicroRNAs (miRNAs) play important roles in many important cellular processes and deregulation of miRNAs is linked to many human diseases including cancer. Although miR-424 has been demonstrated to inhibit progression of hepatocellular carcinoma (HCC), its expression level in serum samples and the potential clinical values remain unknown. Materials and methods: The expression level of miR-424 in the serum clinical samples from HCC patients and healthy volunteers were determined by qRT-PCR. Then the association of serum miR-424 expression level with various important clinicopathological parameters and survival rates was evaluated. Multivariate Cox regression analysis was used to identify the independent risk factors for HCC. Results: The expression level of serum miR-424 was significantly decreased in patients with HCC compared with the healthy volunteers (P<0.01). Reduced expression of serum miR-424 was associated with serum AFP (P=0.048), vein invasion (P=0.006) and TNM stage (P=0.003). In addition, survival analysis showed that HCC patients with lower serum miR-424 expression suffered poorer overall survival (P=0.018) and disease free survival (P=0.008). Moreover, serum miR-424 was demonstrated to be an independent risk factor for HCC. Conclusions: Our findings provide the compelling evidence that the decreased expression of serum miR-424 may serve as a novel biomarker to predict the unfavorable prognosis of HCC patients.     

Up-regulation of miR-335 predicts a favorable prognosis in esophageal squamous cell carcinoma

Introduction: MicroRNAs (miRNAs) are noncoding RNAs that regulate multiple cellular processes during cancer progression. MiR-335 has recently been identified to be involved in tumorigenesis of several cancers such as ovarian cancer and gastric cancer. However, the regulation of miR-335 in esophageal squamous cell carcinoma (ESCC) has not been reported yet. Methods: Expression of miR-335 in tumor and their normal matched tissues was determined by quantitative real-time PCR in 67 ESCC patients and its association with overall survival of patients was analyzed by statistical analysis. Results: The expression level of miR-335 was reduced in malignant tissue samples in comparison to normal matched tissue (P < 0.05). It was also proved that miR-335 expression was associated with ESCC histological grade, lymph node metastasis, tumor stage and clinical stage (P < 0.05). In addition, the Kaplan-Meier survival curves revealed that low miR-335 expression was associated with poor prognosis in ESCC patients. Multivariate analysis showed that miR-335 expression was an independent prognostic marker of overall survival of ESCC patients. Conclusions: The study proves for the first time that miR-335 is down regulated in a majority of ESCC patients. Our results indicate that miR-335 expression is an independent prognostic factor for patients with esophageal cancer, which might be a potential valuable biomarker for ESCC.     

Detection of miR-1246, miR-23a and miR-451 in sera of colorectal carcinoma patients: a case-control study in Cairo University hospital

BackgroundColorectal cancer (CRC) has high morbidity and mortality rates. Invasive techniques and other laboratory tests with variable sensitivity and specificity are currently used in diagnosis. Micro ribonucleic acids (miRNAs) have bio vital roles in cell proliferation and apoptosis. Dys-regulation of miRNAs is linked to tumour genesis. The objective of this study was to evaluate the specificity and sensitivity of serum non-invasive biomarkers (micro-RNAs), miR-1246, miR-23a, and miR-451in CRC patients.MethodsPeripheral expression of three miRNAs (miR-1246, miR-23a and miR-451) was investigated in sera of 37 CRC Egyptian patients and 30 healthy controls, using quantitative real-time polymerase chain reaction trying to reach the optimal non-invasive combination of miRNAs.ResultsSerum miR-1246 was up-regulated in sera of CRC patients compared to normal controls (fold change = 3.55; P<0.001) and showed 100% sensitivity and 80% specificity in diagnosis of CRC. Serum miR-451 was significantly down-regulated in CRC patients (fold change = -4.86; p= 0.014), whereas, miR-23a was down-regulated but this was not statistically significant.ConclusionUp-regulation of miR-1246 and down-regulation of miR-451 in the sera of primary CRC Egyptian patients were confirmed with high sensitivity and specificity. Large-scale studies on a wider spectrum of miRNAs in Egyptian CRC patients are needed.     

Low miR-1273a expression predicts poor prognosis of colon cancer and facilitates tumor cell proliferation,migration, and invasion

MicroRNAs (miRNAs) have been indicated to be frequently dysregulated in various cancers and promising biomarkers for colon cancer. The present study aimed to assess the prognostic significance and biological function of miR-1273a in colon cancer. The expression levels of miR-1273a was estimated using quantitative real-time polymerase chain reaction. Kaplan-Meier survival curves and Cox regression analysis were used to evaluate the prognostic value of miR-1273a in patients of colon cancer. The effects of miR-1273a on cell proliferation, migration, and invasion were investigated by cell experiments. The expression of miR-1273a was downregulated in colon cancer tissues and tumor cell lines compared with the normal controls (all P<0.001). The aberrant expression of miR-1273a was associated with vascular invasion (P=0.005), differentiation (P=0.023), lymph node metastasis (P=0.021), and TNM stage (P=0.004). The patients with low miR-1273a expression had low overall survival compared with the patients with high miR-1273a expression (log-rank P=0.002). miR-1273a was detected to be an independent prognostic biomarker for patients. Furthermore, the results of cell experiments revealed that miR-1273a downregulation promoted, while miR-1273a upregulation suppressed the cell proliferation, migration, and invasion. In conclusion, all data indicated that a downregulated expression of miR-1273a predicted poor prognosis for colon cancer and enhanced tumor cell proliferation, migration, and invasion. Thus, we suggest that methods to promote miR-1273a expression may serve as novel therapeutic strategies in colon cancer.     

Up-regulation of miR-630 in clear cell renal cell carcinoma is associated with lower overall survival

Introduction: MicroRNAs (miRNAs) are noncoding RNAs that regulate multiple cellular processes during cancer progression. MiR-630 has recently been identified to be involved in tumorigenesis of several cancers such as lung cancer and gastric cancer. However, the regulation of miR-630 in clear cell renal cell carcinoma (ccRCC) has not yet been reported before. Methods: Expression of miR-630 was evaluated by quantitative real-time PCR in tumour and their normal matched tissues in n = 92 ccRCC patients, and its association with overall survival of patients was analyzed by statistical analysis. Results: The expression level of miR-630 was significantly higher in renal cancer in comparison to normal matched tissue (P < 0.05). It is also proved that miR-630 expression was to be associated with renal cancer histologic grade, lymphnode metastasis, distant metastasis (P < 0.05). In addition, the Kaplan-Meier survival curves revealed that high miR-630 expression was associated with poor prognosis in ccRCC patients. miR-630 expression was an independent prognostic marker of overall ccRCC patient survival in a multivariate analysis. Conclusions: The study proves for the first time that miR-630 is upregulated in a majority of ccRCC patients. It also shows that miR-630 expression is an independent prognostic factor for patients with renal cancer, which might be a potential valuable biomarker for ccRCC.     

Association between mir-24 and mir-378 in formalin-fixed paraffin-embedded tissues of breast cancer

Background: MiR-24/378 is thought to be onco-miRNAs for their ability of enhancing tumor growth. The objective of this study was to evaluate the potential predictive value of miR-24/378 expression in formalin-fixed paraffin-embedded tissues of breast cancer patients. Methods: The expression of miR-24/378 was examined in 101 breast cancer patients and 40 controls using real-time quantitative PCR. All statistical analyses were performed using SPSS16.0. Results: We found that miR-24 and miR-378 were significantly up-regulated in breast cancer patients compared with controls (all P < 0.01). The expression levels of the two miRNAs were highly correlated with each other in breast cancer patients, with r = 0.778 between miR-24 and miR-378. Moreover, the two miRNAs exhibited great capability of discriminating between cancer patients and controls by ROC analysis. MiR-24 and miR-378 showed 0.79 and 0.807 AUC values respectively. Conclusions: Over-expression of miR-24 and miR-378 in FFPE tissue of breast cancer patients might conduct as an ideal source for biomarker discovery and validation in breast cancer patients.     

MicroRNA-21 and microRNA-29a modulate the expression of collagen in dermal fibroblasts of patients with systemic sclerosis

MicroRNAs (miRNAs) are well-known candidates for modulating the dysregulated signaling pathways during fibrosis. In this study, we investigated the expression pattern of 16 miRNAs, which have previously been confirmed or predicted to target genes involved in extracellular matrix (ECM) homeostasis. Primary culture of dermal fibroblasts was obtained from skin biopsies of diffused cutaneous SSc (dcSSc) patients and healthy controls. Expression of let-7a, miR-1, miR-15a, miR-17, miR-19a, miR-20a, miR-21, miR-27b, miR-26a, miR-29a, miR-29b, miR29c, miR-141, miR-125a-5p, miR-193a-3p, and miR-200a were quantified by Real-time PCR. Functional analysis of microRNAs was performed using synthetic oligonucleotides. To further confirm the pro- or anti-fibrotic effects of miRNAs, normal fibroblasts were treated with 10 ng/mL of transforming growth factor (TGF)-β to generate an in vitro model of dermal fibrosis. miR-21 and miR-29a were upregulated and downregulated, respectively, in both dcSSc and TGF-β-treated fibroblasts. We observed that restoration of miR-29a expression or blockade of miR-21 function negatively affected collagen production. COL1A1 expression in SSc fibroblasts is more sensitive to changes of miR-29a and miR-21 expression in compare to normal fibroblasts. miR-29a alone was effective to decrease TGF-β-induced collagen production in dermal fibroblasts. miR-21 and TGF-β had synergistic effects on induction of collagen production. However, neither miR-21 nor miR-29a affected alpha smooth muscle actin (α-SMA) expression in the presence or absence of TGF-β in dermal fibroblasts. miR-21 and miR-29a as pro- and anti-fibrotic miRNAs modulate collagen production in an opposing manner. Focusing on miR-21 and miR-29s as therapeutic targets would be effective in patients with SSc or other fibrotic diseases which show aberrant expression of collagen expression.     

Dysregulated Serum MicroRNA Expression Profile and Potential Biomarkers in Hepatitis C Virus-infected Patients

Objectives: Circulating microRNAs (miRNAs) play critical roles in pathogen-host interactions. Aberrant miRNA expression profiles might have specific characteristics for virus strains, and could serve as noninvasive biomarkers for screening and diagnosing infectious diseases. In this study, we aimed to find new potential miRNA biomarkers of hepatitis C virus (HCV) infection.Methods: Expression levels of broad-spectrum miRNAs in serum samples from 10 patients with HCV viremia and 10 healthy volunteers were analyzed using miRNA PCR arrays. Subsequently, the differential expression of four selected miRNAs (miR-122, miR-134, miR-424-3p, and miR-629-5p) was verified by qRT-PCR in the serum of 39 patients compared with that in 29 healthy controls. Receiver operating characteristic (ROC) curve analysis was performed to evaluate their potential for the diagnosis of HCV infection.Results: miRNA PCR array assays revealed differential expression of 106 miRNAs in sera of HCV patients compared with that in healthy controls. Serum hsa-miR-122, miR-134, miR-424-3p, and miR-629-5p were well identified. The ROC curves showed that miR-122, miR-134, miR-424-3p, and miR-629-5p could distinguish HCV patients with preferable sensitivity and specificity. In addition, Correlation analysis indicated serum miR-122 expression was positive correlation with ALT/AST levels. Functional analysis of target proteins of these miRNAs indicated the involvement of viral replication, inflammation, and cell proliferation.Conclusion: HCV patients have a broad ''fingerprint'' profile with dysregulated serum miRNAs compared with that in healthy controls. Among these, serum hsa-miR-122, miR-134, miR-424-3p, and miR-629-5p are identified as promising indication factors of the serum miRNA profile of HCV infection. Particularly, miR-122 could be one of serum biomarkers for early pathological process of HCV. However, more miRNA biomarkers and biological functions of these miRNAs require further investigation.     

miRNA 表达与免疫细胞因子相关性在原发性肝癌早期诊断和预后中的作用

目的:检测miR-146a、miR-224、miR-34c、miR-200a、miR-148b、miR-375 六种miRNAs 在原发性肝癌中的表达变化及其与HBsAg、抗-HBs、HBeAg、抗-HBe、抗-HBc 和IL-12、IL-4、IL-6、IL-10、IFN-γ、TNF-α等炎症因子表达的相关性,以验证循环miRNA 是否可作为理想的血源性新型生物标志物用于原发性肝癌的早期检测。方法:收集肝炎、肝硬化患者及健康对照组静脉血,并收集原发性肝癌患者癌组织和癌旁组织。提取总RNA 后通过实时定量PCR 检测并比较各组miRNA 的相对表达水平,同时检测miRNA 表达水平变化与血清肿瘤标志物AFP、CEA、CA19-9、CA125 表达的关系;并检测miRNAs 表达水平变化与HBsAg、抗-HBs、HBeAg、抗-HBe、抗-HBc 和炎症因子IL-12、IL-4、IL-6、IL-10、IFN-γ、TNF-α表达相关性。结果:相对于健康组,miR-34c、miR-224、miR-146a 在PHC 组血清和组织中表达显著上调;miR-200a、miR-148b、miR-375 在PHC 组血清和组织中表达显著下调,差异具有统计学意义。HBsAg 与血清miR-375 和miR-146a 存在回归关系,miR-375 随HBsAg 表达水平升高而降低,而miR-146a 随HBsAg 表达升高而升高。IFN-γ与miR-146a 存在回归关系, miR-146a 随IFN-γ表达水平降低而升高,miR-375 和miR-146a 诊断能力大于CA19-9 和AFP。结论:miR-146a、miR-224、miR-34c、miR-200a、miR-148b、miR-375 在原发性肝癌血清和组织中存在表达差异,其中miR-375 和miR-146a 诊断能力优于AFP 和CA19-9,血清miR-375 和miR-146a 可能成为新的肝癌早期诊断标志。     

MiR-34a inhibits oral cancer progression partially by repression of interleukin-6-receptor

Previous reports revealed that a significant decrease of miR-34a in oral cancer. But the role of miR-34a in oral cancer needs further research. In the present study, we will investigate the effect of miR-34a on oral cancer cell phenotypes. First, it was verified that miR-34a expression was lower in oral cancer tissues compared with their normal controls, so did the oral cancer cells. Next, it was showed that miR-34a overexpression in oral cancer cells could inhibit cell proliferation, G1 phase arrest, metastasis and epithelial mesenchymal transition. It was predicted that interleukin-6-receptor (IL6R) was a potential target gene of miR-34a by bioinformatics analysis and identified by luciferase assay. It was further showed that miR-34a inhibited oral cancer progression via IL6R. Collectively, our findings suggested that miR-34a may function as a tumor suppressor in oral cancer by targeting IL6R.     

miR-34a predicts survival of Ewing's sarcoma patients and directly influences cell chemo-sensitivity and malignancy

Identification of factors to detect chemotherapy-resistant tumours at diagnosis is a first priority for risk-adapted therapy in the oncology of children and young adults, where more individualized, effective, and less toxic treatments are highly desirable. In this study, we analysed the miRNAs discriminating Ewing's sarcoma (EWS) patients with different clinical outcomes in order to identify new indicators of prognosis. miRNA expression was investigated in 49 primary EWSs by using the Agilent human miRNA microarray v.2 and/or qRT-PCR. Statistical power of the samples studied for miRNA expression was verified, indicating adequate sample size. Microarray analysis defined a signature of five miRNAs (miR-34a, miR-23a, miR-92a, miR-490-3p, and miR-130b) as an independent predictor of risk for disease progression and survival. Validation analysis in the extended sample set indicated that both miR-34a and miR-490-3p achieved sufficient statistical power to predict prognosis. Results were particularly robust for miR-34a, which appeared associated with either event-free or overall survival and emerged as a significant predictor also after multivariate analysis. Patients with the highest expression of miR-34a did not experience adverse events in 5 years; in contrast, patients with the lowest expression recurred within 2 years. High expression of miR34a can be detected also in paraffin-embedded tissues by in situ hybridization, thus contributing to an easy routine evaluation of this miRNA. Functional analysis of miR-34a in EWS cell lines indicated that when miR-34a expression was enforced, cells were less proliferative, less malignant, and sensitized to doxorubicin and vincristine. Expression of miR-34a could be increased in p53wt cells by treatment with nutlin-3a. Accordingly, nutlin-3a synergizes with doxorubicin. Overall, our data indicate that miR-34a expression is a strong predictor of outcome in EWS. Restoration of miR-34a activity may be useful to decrease malignancy and increase tumour sensitivity to current drugs, so sparing excessive long-term toxicity to EWS patients.     

miR-144、miR-451在胃癌组织中的表达及其临床意义

目的探究胃癌患者组织中miR-144、miR-451的表达与临床病理参数及预后的关系。方法2013年6月至2014年6月,收集115例胃癌患者的癌组织及癌旁正常组织,采用实时定量PCR检测组织中miR-144、miR-451的表达水平;分析胃癌组织中miR-144、miR-451的表达与患者临床病理参数的关系,采用Kaplan-Meier生存曲线评估miR-144、miR-451的表达与患者预后的关系,并采用Cox回归模型分析胃癌患者预后的影响因素。结果胃癌组织中miR-144相对表达量为0.214±0.069,低于癌旁正常组织的1.124±0.157,miR-451相对表达量为0.354±0.087,低于癌旁正常组织的1.084±0.108,差异均有统计学意义(均P<0.05);miR-144、miR-451的表达均与肿瘤大小、淋巴结转移、远处转移及TNM分期有关(均P<0.05)。Kaplan-Meier生存分析结果表明,与miR-144高表达组、miR-451高表达组相比,miR-144低表达组、miR-451低表达组患者术后5年总生存率较低,术后中位生存时间较短(均P<0.05)。Cox回归模型发现,远处转移、较高TNM分期、miR-144低表达、miR-451低表达是影响胃癌患者预后的危险因素(均P<0.05)。结论胃癌组织中miR-144、miR-451呈低表达,其与患者病情进展和预后有关,检测胃癌组织中miR-144、miR-451的表达可能有利于患者的病情和预后判断。     

MiR-21-5p,miR-34a,and human telomerase RNA component as surrogate markers for cervical cancer progression

Objective

This study aimed to demonstrate the predictive value of miR-21-5p, miR-34a, and human telomerase RNA component (hTERC) in cervical cancer (CC) development and evaluated their potential possibility for future clinical applications.

Down-regulation of miR-497 is associated with poor prognosis in renal cancer

Introduction: Clear cell renal cell carcinoma (ccRCC) is the most common type of cancer in the adult kidney, and the prognosis of metastatic ccRCC remains poor with high mortality. Recent study indicated that microRNAs (miRNAs) played critical roles in tumor progression. The aim of this study was to investigate the expression, biological role and clinical significance of miR-497 in ccRCC. Methods: Quantitative real-time PCR (qRT-PCR) was performed to detect the expression of miR-497 in renal cancer cell lines and ccRCC tissues. The association between miR-497 expression and overall survival was estimated by the Kaplan-Meier method. Gain of function assays were performed in the 786-O renal cancer cell line. Results: Expression of the miR-497 was significantly decreased in renal cancer cell lines and ccRCC tissues when compared with normal human proximal tubule epithelial cells and adjacent non-tumor tissues. Decreased miR-497 expression was significantly associated with tumor stage, histological grade and lymph node metastases. Significantly shorter overall survival was observed in patients with lower expression of the miR-497. Overexpression of miR-497 significantly inhibited renal cancer cell proliferation, migration and invasion. Conclusions: Our results demonstrated that miR-497 was decreased in ccRCC tissues and may provide a potential prognostic biomarker and a potential target for therapeutic intervention.     

Up‐regulation of miR‐455‐5p by the TGF‐β–SMAD signalling axis promotes the proliferation of oral squamous cancer cells by targeting UBE2B

MicroRNAs (miRNAs) are involved in the tumourigenesis of various cancers by regulating their downstream targets. To identify the changes of miRNAs in oral squamous cell carcinoma (OSCC), we investigated the expression profiles of miRNAs in 40 pairs of OSCC specimens and their matched non‐tumour epithelial tissues. Our data revealed higher miR‐455‐5p expression in the tumour tissues than in the normal tissues; the expression was also higher in oral cancer cell lines than in normal keratinocyte cell lines. MiR‐455‐5p knockdown reduced both the anchorage‐independent growth and the proliferative ability of oral cancer cells, and these factors increased in miR‐455‐5p‐overexpressing cells. Furthermore, by analysing the array data of patients with cancer and cell lines, we identified ubiquitin‐conjugating enzyme E2B (UBE2B) as a target of miR‐455‐5p, and further validated this using 3′‐untranslated region luciferase reporter assays and western blot analysis. We also demonstrated that UBE2B suppression rescued the impaired growth ability of miR‐455‐5p‐knockdown cells. Furthermore, we observed that miR‐455‐5p expression was regulated, at least in part, by the transforming growth factor‐β (TGF‐β) pathway through the binding of SMAD3 to specific promoter regions. Notably, miR‐455‐5p expression was associated with the nodal status, stage, and overall survival in our patients, suggesting that miR‐455‐5p is a potential marker for predicting the prognosis of patients with oral cancer. In conclusion, we reveal that miR‐455‐5p expression is regulated by the TGF‐β‐dependent pathway, which subsequently leads to UBE2B down‐regulation and contributes to oral cancer tumourigenesis. Copyright © 2016 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.