Fig. 7

Effect of DS–CuO NPs on protein level of inhibitor subunit I kappa (Iκ) B using immunohistochemical technique. a Immunohistochemical staining images of IκB in the untreated and DS–CuO NPs- and DS–Cu-treated MDA-MB 231, A549 and Huh7 cells (magnification, 100 ×; scale bar, 50 µm) with maximum magnification for brown stained IκB⁺ DS–CuO NPs-treated cancer cells declaring its cellular localizations in both nucleus and cytoplasm. b Percentage of IκB⁺-immunostained cell population in the untreated and treated MDA-MB 231, A549 and Huh7 cells. Data (mean ± SEM), DS–CuO NPs were compared to DS–Cu and considered significantly different at p <  < 0.05*, < 0.005**, < 0.001***