To this end, we demonstrate that the activation of NK cells during chronic IL-2 stimulation and TGFβi potently induces NK cell hypersecretion of interferon-gamma (IFNγ) and tumor necrosis factor-alpha (TNFα) in response to tumor targets which persists for at least one month in vitro after the removal of TGFβ. This evidence concerns the gene TGFB1 and neoplasm.