MiR-613: a novel diagnostic and prognostic biomarker for patients with esophageal squamous cell carcinoma.

MicroRNA-613 (miR-613) plays important roles in tumorigenesis and cancer progression. We aimed to evaluate its expression level and potential for diagnosis and prognosis in esophageal squamous cell cancer (ESCC). We examined miR-613 expression in 60 pairs of ESCC cancerous and matched paracancerous tissues, serum samples from 75 ESCC patients and 75 healthy volunteers, and 105 formalin-fixed paraffin-embedded (FFPE) tissue samples using quantitative reverse transcription polymerase chain reaction. Receiver-operating characteristic (ROC) curve analysis, Kaplan-Meier method, and Cox regression were applied to analyze its diagnostic and prognostic value. MiR-613 was significantly decreased in ESCC tissue compared with paracancerous tissue (P < 0.001). Moreover, the expression level of miR-613 was significantly reduced with increased T stage of ESCC. Statistically significant difference between ESCC patients and healthy controls in expression level of miR-613 (0.89 ± 0.73 vs. 1.71 ± 1.03, P < 0.001) was found. The area under the ROC curve (AUC) based on serum miR-613 was 0.767 ± 0.040. We also performed analysis on early-stage patients and revealed that the AUC value was 0.728 ± 0.052 (P < 0.001). The Kaplan-Meier curve revealed that the downregulation of miR-613 was related to worse overall survival (OS) and progression-free survival (PFS) of ESCC patients (P = 0.018 and P = 0.035, respectively). Furthermore, the multivariate analysis identified miR-613 to be an independent prognostic factor for OS and PFS (P = 0.031 and P = 0.006, respectively) In conclusion, miR-613 is significantly reduced in cancerous tissue and serum samples of ESCC patients. It can serve as an ideal indicator for the diagnosis and prognosis of ESCC.