PTGDR and gastric cancer: As the results showed, in the wound-healing assay (Supplementary Fig. S4a, b) and the Transwell assay (Fig. 4j, and Supplementary S4c–e), overexpression of NTN1 reversed the inhibitory effect on GC cells induced by si-DIAPH2-AS1, while transfection of sh-NTN1 significantly weakened the pro-metastasis phenotype of GC cells resulted from the overexpression of DIAPH2-AS1.