Background: MicroRNAs were important regulators of tumors and the expression of miRNA-221 was associated with malignant proliferation and invasion in many tumors. The aim of this study is to explore the expression of miRNA-221 in non-small cell lung cancer (NSCLC) tissues and its correlation with prognosis.
Methods: We retrospectively analyzed the clinical characteristics of 117 NSCLC patients who underwent surgery in our hospital from November 2005 to January 2007. Real-time PCR was used to detect the expression of miRNA-221. Chi-square test was utilized to analyze the relationship between miRNA-221 expression and clinicopathologic features. Survival curves were plotted by using the Kaplan-Meier method and compared by the Log-rank test. A Cox proportional hazard regression model was applied to examine the joint effect of covariants. A P-value less than 0.05 was evaluated as statistically significant.
Results: The patients were divided into two groups according to the relatively expression of miRNA-221. No statistically significance was observed between the expression of miRNA-221 and the clinicopathologic parameters, including gender (χ(2)=0.070, P=0.791), histology (χ(2)=0.414, P=0.520), p-TNM stage (χ(2)=0.068, P=0.794) and history of smoking (χ(2)=0.206, P=0.650). Kaplan-Meier analysis showed that high expression of miRNA-221 was closely associated with a shorter survival time (P<0.001). Finally, both univariate and multivariate analyses demonstrated that high miRNA-221 expression might be a poor prognostic marker of NSCLC patients.
Conclusions: Our results indicated that down-regulation of miRNA-221 was associated with poor prognosis of patients with NSCLC. MiRNA-221 may serve as a molecular prognosis marker for patients with NSCLC.
背景与目的 microRNAs是肿瘤的重要调控因子，其中miRNA-221的表达与多种肿瘤相关，本研究旨在探讨miRNA-221在非小细胞肺癌组织中的表达及其与预后的关系。方法 分析江苏省肿瘤医院2005年11月-2007年1月期间行手术治疗的117例非小细胞肺癌患者的临床资料。采用实时定量逆转录聚合酶链反应检测上述病例肺癌标本中miRNA-221的水平；应用χ2检验分析miRNA-221表达水平与各临床病理参数的关系；采用Kaplan-Meier方法分析miRNA-221表达与非小细胞肺癌生存期（overall survival, OS）之间的关系；采用Cox风险比例模型分析各个协变量的联合效应。以P<0.05认为差异有统计学意义。结果 miRNA-221的表达量与患者年龄相关，与患者性别（χ²=0.070, P=0.791）、病理类型（χ²=0.414, P=0.520）、p-TNM分期（χ²=0.068, P=0.794）及吸烟史（χ²=0.206, P=0.650）无明显关系；生存分析显示miRNA-221高表达组患者生存期显著低于低表达组（P<0.001）。Cox风险比例模型分析显示miRNA-221表达可作为非小细胞肺癌患者预后不良的标志。结论 miRNA-221的高表达提示非小细胞肺癌患者预后较差，是潜在的肺癌预后预测分子标志物。