中文摘要：

目的：探索胃癌患者血清miR-17-92簇的表达水平,评价其对胃癌诊断和检测的临床应用价值.方法：qRT-PCR法检测79名胃癌患者及38名正常对照组中血清miR-17-92簇的表达水平.结果：miR-NAs可以在血清中稳定存在.血清miR-17-3p、miR-17-5p、miR-18a-5p、miR-19a-3p、miR-19b-3p、miR-20a-5p、miR-92a-3p的表达 水平在胃癌患者中均高于正常对照组（P=0.005、0.009、0.006、0.003、0.045、0.016）.miR-17-3p 在七个miRNA中的ROC曲线下面积最大,且诊断的特异度高达89.00%.miR-17-3p和miR-19a-3p 联合检测对胃癌诊断特异度有明显提 高,高达94.70%,灵敏度为63.16%.miR-17-92簇的表达与胃癌的分期及淋巴结转移有关（P＜0.01、=0.02）.结论：血清miR-17-92簇可以作为一种潜在的胃癌生物标志物,辅助胃癌诊断.

英文摘要：

Objective：To explore the expression level of the serum miR - 17 - 92 cluster in gastric cancer. Meth- ods：Quantitative reverse transcription polylnerase chain reaction（qRT - PCR） was used to test the levels of serum lniRNAs of 79 gastric cancer patients and 38 healthy controls. Results：miRNAs were stable and detectable in all ser- um samples. The levels of miR - 17 - 3p, miR - 17 - 5 p, miR - 18a - 5 p, miR- 19 a - 3p, miR - 19b - 3p, miR - 20a-5p,miR-92a-3p were significantly higher than that in healthy eontrols（P =0.005,0.009,0.006,0.003, 0.045,0.016,respectively）. The values of the area under the receiver - operating characteristic （ROC） curve were 0. 942 for the miR - 17 - 3 p, which was the largest alnong the seven miRNAs. And the specificity reached 89.00%. Combined ROC analyses using miR - 17 -3p and miR -92a -3p revealed an elevated AUC （area under crewel of 0. 952 with 63.16% sensitivity and 94.70% specificity in diseriminating gastric cancer. Conclusion：Cir- culating miR - 17 -92 might provide new complementary tumour biomarkers for the diagnosis of gastric cancer.