高表达MiR-92a对结直肠癌患者临床病理特征及预后影响的研究

Effect of Over-Expression MiR-92a on Clinicopathological Features and Prognosis of Patients with Colorectal Cancer

目的 探讨高表达的micro RNA-92a（miR-92a）对结直肠癌（CRC）患者临床病理特征和预后的影响及其机理。方法 用实时荧光定量PCR法对108例CRC患者病理标本中miR-92a和磷酸酶基因（phosphatase and tensin homologue,PTEN）的表达水平进行定量检测,以中位表达水平为截断值,分析不同表达水平的miR-92a与CRC患者临床病理特征和预后的关系,以及miR-92a和PTEN基因表达之间的关系。结果 高表达的miR-92a不仅与CRC患者的淋巴结转移（χ^2=8.045,P=0.007）、远处转移（χ^2=5.708,P=0.030）和较高的TNM分期（χ^2=6.366,P=0.019）有关,还与PTEN基因表达的下调相关（χ^2=21.333,P〈0.001）;但与患者的年龄、性别、肿瘤大小、肿瘤位置、浸润深度和分化程度无关（P〉0.05）。Kaplan-Meier生存分析结果显示,高表达的miR-92a（P〈0.001）和低表达的PTEN基因（P=0.002）能够潜在地预测较差的CRC患者总体生存率。结论 高表达的miR-92a可能通过下调抑癌基因PTEN的表达水平,从而导致CRC患者较差的临床预后。

Objective To investigate the impact and mechanism of over-expression microRNA-92a （miR-92a） in clinicopathologic feature and prognosis of patients with colorectal cancer （CRC）. Methods The expression levels of miR-92a and phosphatase and tensin homologue （PTEN） gene in 108 cases of colorectal cancer tissues were detected by using real-time fluorescent quantitative PCR （RT-PCR）, and they were categorized as low or high in relation to the median value. Then the association between different levels of miR-92a gene expression and dinicopathologic feature and prognosis of CRC patients were evaluated. Moreover, the relationship between the expressions of miR-92a and PTEN gene were analyzed. Results High expression of miR-92a not only associated with lymph node metastasis （X2=8.045, P=0.007）, distant metastasis （X2=5.708, P=0.030）, and TNM staging （X2=6.366, P=0.019） of CRC patients, but also related to the down-regulated of PTEN gene expression （X2=21.333, P〈0.001）. However, up-regulated miR-92a expression was negatively correlated with age, gender, tumor size, tumor location, depth of invasion and tumor differentiation. In addition, Kaplan-Meier survival curves showed that over-expression of miR-92a and low-expression of PTEN gene could potentially predict poor overall survival of CRC patients. Conclusion The high expression of miR-92a can lead to a poor clinical prognosis of CRC patients through decreasing the expression level of PTEN gene.