MicroRNA 421 suppresses DPC4/Smad4 in pancreatic cancer

► We identify miR-421 as a novel potential regulator of DPC4/Smad4. ► The expression levels of miR-421 and DPC4/Smad4 are inversely correlated in human clinical specimens of pancreatic cancer. ► Overexpression of miR-421 represses the reporter activities driven by the 3′-UTR of DPC4/Smad4 and DPC4/Smad4 protein level in pancreatic cancer cell. ► Ectopic expression of miR-421 promotes the proliferation and colony formation of pancreatic cancer cell.