SNAT1在非小细胞肺癌中的表达及其与预后的关系

目的 探讨人钠耦合中性氨基酸转运蛋白1（SNAT1）在非小细胞肺癌（NSCLC）中的表达及其临床意义。方法 构建含98例NSCLC组织芯片，免疫组化检测NSCLC组织和癌旁正常组织中SNAT1蛋白的表达，分析其表达与NSCLC临床病理特征及患者生存之间的关系。构建sh-SNAT1表达载体质粒转染肺癌A549细胞，分别用MTT法和克隆形成实验检测敲除SNAT1表达后其增殖能力的变化。结果 NSCLC组织中SNAT1阳性表达率为53.1％（52／98），而癌旁正常组织中不表达。NSCLC组织中SNAT1表达与淋巴结转移、分期和分化程度均呈正相关，其中SNAT1蛋白阳性表达患者的中位总生存时间为23.3个月，明显低于阴性表达者的40.5个月（P＜0.001）。敲除SNAT1表达时NSCLC细胞的增殖能力显著减弱。结论 SNAT1在NSCLC发生发展过程中过度活化，是评估NSCLC患者预后的重要指标之一。

Expression of SNAT1 in non-small cell lung cancer and its relationship with prognosis

Objective To detect SNAT1 protein expression and determine its clinical significance in non-small cell lung cancer（NSCLC）. Methods Tissue microarray blocks containing 98 NSCLC tumor specimens were constructed. Expression of SNAT1 in NSCLC specimens and adjacent cancer tissues was analyzed using immunohistochemistry. A549 cells were transfected with plasmid vector which expressed sh-SNAT1. MTr assay and cloning formation assay were used to detect proliferation of A549 cells which were knocked down SNAT1 expression. Results The positive expression of SNAT1 was 53.1% in NSCLC, while SNAT1 wasn＇t expressed in adjacent cancer tissues. SNAT1 expression was significantly associated with lymph node metastasis, tumor stage and differentiation. Patients with SNAT1 positive expression had significantly shorter survival time than those with SNAT1 negative expression（23.3 vs. 40. 5months, P〈0. 001）. Downregulating expression of SNAT1 leaded to the inhibition of cell growth. Conclusion SNAT1 expression significantly increased with the progression of NSCLC, suggesting the importance of SNAT1 as a potential biomarker in predicting the outcome of patients with NSCLC.