PDCD1LG2 and neoplasm: Recent studies signify the predictive, prognostic and therapeutic value of PD-L2 for GC immunotherapy, as evidenced by the association of PD-L2 and PD-L2 mRNA expression with tumor progression and poor survival, as well as the infiltration of myeloid dendritic cells, CD4+ T-cells and CD8+ T-cells (17–19).