Shimizu et al. [28] have shown that the presence of a diphenylamine moiety enhanced the inhibitory activity in the autophosphorylation of FGF-R2 of a series of quinoline derivatives, among which 2-[[2-[[4-[4-[[4-(1,1-dimethylethyl)phenyl]amino]phenoxy]-6-methoxy-7-quinolinyl]oxy]ethyl]amino]ethanol has been identified as a potent inhibitor in autophosphorylation of FGF-R2 with IC50 value of 88 nM and inhibited the proliferation of the human scirrhous gastric carcinoma cell line, OCUM-2MD3, in a concentration-dependent manner. The gene discussed is FGFR2; the disease is gastric carcinoma.