The result indicated that miR-139-3p and circ-PTPDC1 were present in the circ-PTPDC1 pull-down pellet compared with the control group (Fig. 6D). We then detected the miR-139-3p expression level in TGCA unpaired and paired miRseq database, the results (Fig. 6E) showed that miR-139-3p is significant lower in GC tissues, which are consistent with our results via qRT-PCR analysis in tumorous tissues and adjacent noncancerous tissues of 128 GC patients (Fig. 6F). qRT-PCR further confirmed that circ-PTPDC1 knockdown could increase the miR-139-3p level and miR-139-3p suppresses circ-PTPDC1 level. This evidence concerns the gene PTPDC1 and gastric cancer.