TAP2 and lung cancer: TAP deficiencies have been observed in a wide variety of human cancers, including cervical carcinoma (68), head and neck carcinoma (69), melanoma, gastric cancer (65, 66), and lung cancer, with up to 70% of NSCLC expressing low levels of TAP1 and/or TAP2 (77), and are associated with tumor escape from immune system control.