A positive feedback loop between AlkB homolog 5 and miR-193a-3p promotes growth and metastasis in esophageal squamous cell carcinoma.

Esophageal squamous cell carcinoma (ESCC) is one of the most frequent malignancies worldwide. miR-193a-3p acts as an oncogene or tumor suppressor in different cancers. However, the functional role and regulatory mechanism of miR-193a-3p in ESCC remain to be elucidated. Our results demonstrated that miR-193a-3p expression was significantly upregulated and associated with advanced TNM stage, recurrence, and poor prognosis in ESCC patients. miR-193-3p targeted ALKBH5 and suppressed its expression. ALKBH5 inhibited miR-193a-3p expression in turn. ALKBH5 affected the primary miR-193a-3p processing by negatively regulating its m6A modification. These findings suggested a positive feedback regulation between miR-193a-3p and ALKBH5 in ESCC cells. Moreover, the functional assays indicated that the miR-193-3p-ALKBH5 feedback loop promoted the proliferation, migration and invasion ability of ESCC cells in vitro, and facilitated tumor growth and metastasis in vivo. Collectively, our current study identified a novel positive feedback regulation between miR-193a-3p and ALKBH5 in ESCC, which may be helpful to gain insight into ESCC pathogenesis and provide novel therapeutic target for ESCC.