PTPDC1 and gastric cancer: The transwell assay demonstrated that the invasion ability of GC cells was inhibited by miR-139-3p and si-circ-PTPDC1 (Fig. 6K). Scratch wound assay showed that the migration rate of GC cells transfected or co-transfected with miR-139-3p and si-circ-PTPDC1 was significantly lower than that of GC cells transfected with si-NC (Fig. 6L). Collectively, these results indicate that circ-PTPDC1 acted as a molecular sponge of miR-139-3p and miR-139-3p suppresses the proliferation, migration and invasion of GC cells.