TAP2 and lung carcinoma: Our studies also reveal a complex and previously unrecognized mechanism underlying TAP2 downregulation in the protection of lung cancer cells to T-cell mediated killing that involves: i) limiting the levels of high affinity surface class-I HLA-peptide complexes, ii) suppression of proinflammatory signals via SOCS1 upregulation; and iii) reduced sensitivity to proinflammatory cytokines.