Objective: This study aimed to examine the prognostic value of miR-421 in terms of overall survival (OS) and recurrence free survival (RFS) in ESAD and its potential regulatory network.
Patients and methods: An in-silico analysis was conducted using data from large databases, including The Cancer Genome Atlas-Esophageal Carcinoma (TCGA-ESCA), Starbase 3.0 and GeneMANIA.
Results: Both esophageal adenocarcinoma (ESAD) and esophageal squamous cell carcinoma (ESCC) tissues had significantly upregulate miR-421 expression, compared with adjacent normal tissues. Upregulated miR-421 expression was associated with shorter OS, but not RFS in ESAD. In patients with ESCC, no difference in miR-421 expression was observed regards to OS or RFS status. Univariate and multivariate analysis showed that high miR-421 expression was independently associated with shorter OS (HR: 2.77, 95%CI: 1.41-5.46, p<0.01), after adjustment of histological grade and pathological stages. The predicted regulatory network of miR-421 in ESAD includes both tumor suppressors and oncogenes, which makes the role of miR-421 quite mysterious in this cancer.
Conclusions: MiR-421 expression might serve as a valuable prognostic biomarker in patients with ESAD. But future molecular studies are required to explore the exact regulatory effect of it.