TAP2 and breast cancer: Notably, downregulation of TAP1 and TAP2 has been described as an immune evasion mechanism in gliomas [47], a subtype of breast cancer [48], and murine fibroblasts after oncogenic transformation [49], similar to the downregulation of β2-Microglobulin in diffuse large B cell lymphomas and colorectal carcinomas [50,51].