IFNG and gastrointestinal stromal tumor: •Increased NK cell numbers post therapy (Ohyashiki et al., 2012) •No impact on cytotoxicity and cytokine production in vitro (Salih et al., 2010) •Increased NKp30- and NKG2D-dependent lysis and IFN-γ production in GIST-patients (Menard et al., 2009) •Increased INF-γ production in GIST patients correlated with clinical outcome (Borg et al., 2004)