In addition, P-selectin glycoprotein ligand-1 (PSGL-1, encoded by SELPLG), identified as an immune checkpoint in tumor immunity, inhibits T-cell proliferation (Prieto-Bermejo et al., 2021), whereas Selplg-deficient T cells exhibit functional exhaustion (Dong et al., 2020). This evidence concerns the gene SELPLG and neoplasm.