This study aimed to assess plasma lncRNA microRNA-31 hist gene (MIR31HG) as a novel diagnostic and therapeutic biomarker for esophageal squamous cell carcinoma (ESCC) and to investigate its role in ESCC.
Importantly, the high ESCC, marked-ZD esophagus had a 15-microRNA signature, resembling the human ESCC miRNAome, with miR-223, miR-21, and miR-31 as the top-up-regulated species.
We demonstrate that miR-31 is significantly decreased in invasive esophageal cancer cells, while upregulation of miR-31 inhibits growth, migration and invasion of esophageal adenocarcinoma (EAC) and squamous cell carcinoma (ESCC) cell lines. miR-31, in turn, targets SOX4 for degradation by directly binding to its 3'-UTR.
Importantly, esophageal miR-31 and miR-21 levels were directly associated with the appearance of ESCC in ZD rats, as compared with their cancer-free Zn-sufficient or Zn-replenished counterparts.
MiR-31 and miR-142-3p expression were correlated to histological differentiation in ESCC (P < 0.05, Student's t-test); high miR-142-3p expression was associated with a poor prognosis in all 91 ESCC patients (P = 0.014, log-rank) and identified as an independent prognostic factor in ESCC (P = 0.017, univariate Cox; P = 0.022, multivariate Cox).