Additionally, PD-L2 is also expressed on tumor cells and involved in antitumor immune suppression (Latchman et al., 2001; Taube et al., 2014; Yearley et al., 2017; Larsen et al., 2019; Liao et al., 2019; Tanegashima et al., 2019; Nakayama et al., 2020). This evidence concerns the gene PDCD1LG2 and neoplasm.