Resumen de Up-regulation of miR-9 expression as a poor prognostic biomarker in patients with non-small cell lung cancer
T. Xu, X. Liu, L. Han, H. Shen, L. Liu, Yongqian Shu
Purpose Emerging evidences indicate that dysregulated microRNAs are implicated in cancer tumorigenesis and progression. MicroRNA-9 (miR-9) has various expression patterns in diverse human cancers. However, its clinical significance in human non-small cell lung cancer has not yet been elucidated. In the present study, we detected the expression of miR-9 in non-small cell lung cancer and adjacent noncancerous tissues and explored its relationships with clinicopathological characteristics and prognosis.
Methods Expression levels of miR-9 in 116 pairs of non-small cell lung cancer and adjacent normal tissues were detected by real-time quantitative RT-PCR assay. To determine its prognostic value, overall survival (OS) and progression-free survival (PFS) were evaluated using the Kaplan�Meier method. Univariate and multivariate analysis were performed using the Cox proportional hazard analysis.
Results MiR-9 expression in non-small cell lung cancer tissues was significantly higher than that in adjacent normal tissues (p = 0.001), and its up-regulation was significantly correlated to advanced tumor�node�metastasis (TNM) stage (p < 0.001), tumor size (p = 0.013), and lymph node metastasis (p = 0.001). Furthermore, Kaplan�Meier analysis demonstrated that high miR-9 expression clearly predicted poorer PFS (p < 0.001) and OS (p < 0.001). In the multivariate analysis, increased miR-9 expression was an independent prognostic factor for both PFS (p = 0.002) and OS (p = 0.013).
Conclusions MiR-9 was up-regulated in non-small cell lung cancer tissues and correlated with adverse clinical features and unfavorable survival, indicating that miR-9 might be involved in non-small lung cancer progression and could serve as a promising biomarker for further risk stratification in the treatment of this cancer.
