CD8A and neoplasm: Considering the following reasons: (1) Animal experiments showed that NE can inhibit the function of CD8+ T cells; (2) NE can promote the production of ADO; (3) ADO can inhibit the expression of IFN-γ in PBMCs, we speculated that NE could promote ADO production in tumour cells, thereby inhibiting the IFN-γ function of CD8+ T cells.