PCAT1 is up-regulated in both ECC tissue samples and cell lines. Here, we showed that downregulation of PCAT1 following transfection with silencing RNA reduced ECC cell growth and increased cell apoptosis. Additionally, PCAT1 suppression inhibited ECC cell migration and invasion as determined by transwell assay. Furthermore, we determined that PCAT1 is a competing endogenous for microRNA (miR)-122, with bioinformatics analysis and luciferase-reporter assay results demonstrating that PCAT1 regulated WNT1 expression via miR-122. Moreover, PCAT1 downregulation increased levels of glycogen synthase kinase 3b and significantly decreased b-catenin levels in whole cell lysates and nuclear fractions, indicating that PCAT1 silencing inhibited the Wnt/b-catenin-signaling pathway. We also observed that exogenous expression of WNT1 reversed PCAT1-silencing-induced inhibition of ECC cell growth inhibition.