Immunological tolerance, developed by TME, is mainly characterized by ineffective T cell activation due to lack of tumor-associated antigens (TAAs), lack of co-stimulatory signals, T cell exhaustion, presence of immunosuppressive cells (MDSCs, Tregg cell), and expression of programmed cell death 1 ligand 1 (PD-L1) [1,5]. The gene discussed is CD274; the disease is neoplasm.