However, we found that the expressions of some novel checkpoint genes (CD44, ENTPD1, NT5E, and NRP1) were upregulated in the low-ELN signature group, and our study has uncovered that the high expression of NT5E was obviously associated with poor prognosis, cancer cell migration, and metastasis in GC patients (63), and this may be served as a therapeutic target for GC metastasis. This evidence concerns the gene ENTPD1 and cancer.