IFNA1 and neoplasm: Furthermore, the decreased cytolytic activity against tumor cell lines of intratumoral NK cells from cancer patients has also been shown to be increased/restored when IL-2 or IFNα are used either in pretreatment or during cytotoxic assays in vitro, showing that both cytokines could help in re-establishing NK cell function after a prolonged exposure to tumor cells [122,123,124,125,126] (Figure 2).