The expression of certain immune checkpoints (such as PDCD1LG2, HAVCR2, CD276, and IDO1) also played an important role in the regulation of immune response by inhibiting the activation of anti-tumor immunocytes and inducing immune escape (Okazaki et al., 2013; Tang et al., 2020). The gene discussed is PDCD1LG2; the disease is neoplasm.