TAP1 and nasopharyngeal carcinoma: MHC-I expression in NPC showed a positive correlation with CD8+ T cell infiltration (r = 0.098, P = 0.039), GR (r = 0.229, P < 0.001), and TAP1 (r = 0.262, P < 0.001), but it had a negative correlation with FAF2 (r = −0.109, P = 0.022).