PDCD1LG2 and neoplasm: Recently, blocking of programmed death‐1 (PD‐1), programmed death‐1 ligand‐1 (PD‐L1), and programmed death Ligand‐2 (PD‐L2), the construction of antigen chimeric T cells (CAR‐T) and tumor vaccines have become popular immunotherapies Tumorigenesis, progression, and metastasis are closely related to TME.