Clinical significance of the expression of miRNA-21, miRNA-31 and miRNA-let7 in patients with lung cancer

OBJECTIVE: To explore the expression differences of miRNA-21, miRNA-31 and miRNA-let7 between lung cancer patient and healthy people, thereby providing reference for early diagnosis of lung cancer. METHOD: Real-time PCR was employed to determine the expression difference between lung cancer patients (50 cases) and healthy people (24 cases). The clinical data of lung cancer patients were analyzed to explore the correlation between clinicopathological characteristics and expression level of miRNA-21, miRNA-31, miRNA-let7. RESULTS: The relative expression levels of miRNA-21 and miRNA-31 in lung cancer group were obviously higher than those in healthy control group, and the relative expression level of miRNA-let7 in lung cancer group was slightly higher than that in healthy control group. Lung cancer patients with lymph node metastasis had higher expression level than those without lymph node metastasis. The ROC curve showed that the three miRNAs had clinical diagnosis efficiency for lung cancer, and the combined detection of the three miRNAs were more efficient in diagnosing lung cancer. Survival curve analysis suggested that the median survival times of patients in the miRNA-21 and miRNA-31 high expression groups were shorter than those in the low expression groups, and the median survival time of patients in miRNA-let7 high expression group was longer than that in the low expression group. CONCLUSION: Plasma miRNA-21, miRNA-31 and miRNA-let7 may be diagnostic marker for lung cancer.