Abstract: Objective The aim of this study was to explore the expression and clinical significance of serum miR-195 in patients with non-small cell lung cancer(NSCLC).Methods Real-time quantitative PCR(qRT-PCR)was used to detect the expression of serum miR-195 in 100 patients with NSCLC and 90 normal healthy subjects.The clinical significance and significance of its expression in clinical analysis were analyzed.Results Compared with the healthy control group(4.52±1.17),the relative expression of serum miR-195 was decreased in patients with NSCLC(7.26±1.61)(P＜0.01).The relative expression of serum miR-195 in patients with Ⅲ~Ⅳ phase of NSCLC was lower than that in patients with I-II phase of NSCLC.The relative expression of serum miR-195 in patients with lymph node metastasis was lower than that in patients without lymph node metastasis.The relative expression of serum miR-195 in patients with distant metastasis was lower than that in patients without lymph node metastasis.They showed a significant difference(P＜0.05).However,the relative expression of serum miR-195 was not statistically different in patients between squamous cell carcinoma and adenocarcinoma,and there was no statistical difference in highly differentiated,moderately differentiated,and poorly differentiated patients.Logistic regression analysis showed that serum miR-195 was significantly correlated with NSCLC(OR=0.526,95%CI:0.415~0.697,P=0.007).Area under ROC(AUC)of serum miR-195 was 0.875(95%CI:0.826~0.923,P=0.004)for the diagnosis of NSCLC.In addition,the NSCLC patients in the high miR-195 expression group was significantly longer the overall survival time than that of patients with low expression of miR-195 in serum(P＜0.05).Multivariate analysis showed that the serum miR-195 expression was an independent influence factor for NSCLC(HR=0.615,95%CI:0.324~0.783,P=0.011).Conclusion The expression of serum miR-195 is decreased in patients with NSCLC,and it is closely related to staging,lymphatic metastasis,distant metastasis and prognosis of NSCLC.Serum miR-195 is expected to be a molecular marker for potential early diagnosis and prognosis evaluation of NSCLC.

Key words: MiR-195, Non-small cell lung cancer, Serum