Implications of microRNA-197 downregulated expression in esophageal cancer with poor prognosis

The aim of this study was to investigate the significance of the microRNA miR-197 expression level in relation to clinicopathological factors and prognoses of esophageal cancer (EC). MicroRNA was extracted using the Taqman(®) MicroRNA Assay from 46 EC patients at the same tumor node metastasis (TNM) stage, but with different prognoses, who underwent surgery. Paracancerous normal tissues were used as controls. The correlation between miR-197 expression and clinicopathologic features was analyzed, and the significance of miR-197 as a prognostic factor and its relationship with survival was determined. miR-197 expression was lower in patients with poor prognosis than in those with good prognosis (P < 0.05). Kaplan-Meier analysis results showed that the miR-197 expression level is significantly correlated with survival time (P = 0.030), and that patients with higher expression of miR-197 had longer survival times. Cox multi-factor model analysis showed that patient prognosis (P = 0.001), tumor length (P = 0.010) and expression (P = 0.042), and survival time were significantly correlated, with corresponding risks of 9.183, 2.318, and 1.925, respectively. This study supports a role of miR-197 as an anti-oncogene and a biomarker for EC and its relationship with other prognostic factors and survival.