Decreased Expression of MicroRNA-375 in Nonsmall Cell Lung Cancer and its Clinical Significance

Abstract

Objective: Emerging evidence has shown the association of aberrant microRNA-375 (miR-375) expression with tumourigenesis in many types of human malignancy. This prospective study characterized the contribution of miR-375 to the initiation and progression of nonsmall cell lung cancer (NSCLC). Methods: The real-time reverse transcription-polymerase chain reaction was used to examine miR-375 levels prospectively in 96 pairs of samples of NSCLC tissue and adjacent noncancerous tissue (> 2 cm from cancer tissue). The relationship between miR-375 levels and clinico pathological features was also explored. Results: MiR-375 was downregulated in 89% (85/96) of NSCLC samples compared with matched noncancerous tissue samples. Decreased miR-375 correlated significantly with advanced disease stage and lymphatic metastasis. Univariate and multivariate Cox proportional hazard regression analyses revealed that underexpression of miR-375 was an unfavourable prognostic factor for overall survival in NSCLC. Conclusions: This study suggested that miR-375 is a novel prognostic indicator in NSCLC and might be a potential target for diagnosis and gene therapy.