RESUMEN
Objective:To explore the expression of miR-139-5p in small cell lung cancer (SCLC)tissue and its clinical significance, and to clarify the role of miR-139-5p in the occurrence and development of SCLC. Methods:The biological function of miR-139-5p was examined by cell growth,apoptosis and cell cycle analysis. The expressions of miR-139-5p in 50 cases of cancer tissue and paracarcinoma normal tissue were examined by QRT-PCR.Combined with the clinical data,the role of miR-139-5p in clinic was anzlyzed.Results:The expression level of miR-139-5p in SCLC tumor tissue was lower than that in normal lung tissue (P 0.05).The expression level of miR-139-5p in the patient at LD stage was lower than that of the patients at ED stage (P <0.01).The expression level of miR-139-5p in the resistant patients was higher than that of the patients sensitive to chemotherappy (P <0.01).The expression level of miR-139-5p in the survival patients was lower than that in the death patients (P <0.01).Cox regression analysis indicated that miR-139-5p expression and disease stage were the independent prognostic factors for SCLC.Conclusion:miR-139-5p in participates in the occurrence and development of SCLC by inhibiting the cell proliferation,promoting apoptosis and inducing the cell cycle arrest;it may be used as a target gene to evaluate the prognosis of SCLC patients.