IL2 and neoplasm: To determine the impact of IL-2 on HLA class I molecule expression, human PTC K1, TPC-1, BCPAP and non-tumor Nthy-ori 3-1 cells were treated with, or without, recombinant IL-2 (0.1μg/mL) for 24h and the levels of HLA class I expression was characterized by flow cytometry.