The mean ratios of CD107a+ and IFN-γ+ NK cells, under normoxic vs. hypoxic conditions, are summarized in Figure 1C. NK cell tumor cytotoxicity measured by LDH cytotoxicity kit was also decreased in a pO2-dependent manner, indicating that hypoxia inhibited anti-tumor activity of NK cells against all three tumor targets, K562, A375, and MiaPaCa-2, a pancreatic tumor cell line (Figure 1D). This evidence concerns the gene IFNG and neoplasm.