In addition, to verify whether MTAP also played a role in tumor angiogenesis by regulating the ODC activity, we explored the effect of MTAP on tube formation of HUVECs and found that treatment with CM from MTAP-knockdown BT20 cells significantly enhanced the tube-forming ability of endothelial cells while additional DFMO in CM from MTAP-knockdown BT20 cells reversed the enhanced tube-forming ability of HUVECs (Figure 6D). Here, MTAP is linked to neoplasm.