miR326 maturation is crucial for VEGF-C-driven cortactin expression and esophageal cancer progression.

Esophageal cancer is an aggressive human malignancy with increasing incidence in the developed world. VEGF-C makes crucial contributions to esophageal cancer progression that are not well understood. Here, we report the discovery of regulatory relationship in esophageal cancers between the expression of VEGF-C and cortactin (CTTN), a regulator of the cortical actin cytoskeleton. Upregulation of CTTN expression by VEGF-C enhanced the invasive properties of esophageal squamous cell carcinoma in vitro and tumor metastasis in vivo. Mechanistic investigations showed that VEGF-C increased CTTN expression by downregulating Dicer-mediated maturation of miR326, thereby relieving the suppressive effect of miR326 on CTTN expression. Clinically, expression of Dicer and miR326 correlated with poor prognosis in patients with esophageal cancer. Our findings offer insights into how VEGF-C enhances the robust invasive and metastatic properties of esophageal cancer, which has potential implications for the development of new biomarkers or therapies in this setting. ©2014 American Association for Cancer Research.