Then we tested whether Ephrin A1 influenced the colony formation abilities of gastric cancer cells, the results showed that ectopic expression of Ephrin A1 significantly enhanced 3D colony formation of NCI-N87 cells (Fig. 1F,G) and depleted Ephrin A1 expression dramatically reduced the number of colonies in MKN45 cells (Fig. EV3A,B). Here, EFNA1 is linked to gastric cancer.