Fig. 2

Treatments with 75 nm AgNPs reduce the efflux activity of drug-resistant MCF-7/KCR cells without causing significant changes in Pgp expression level. a Histograms of Rhodamine 123 accumulation and b mean Rhodamine 123 fluorescence of verapamil-treated, 5 nm or 75 nm AgNP-treated MCF-7/KCR cells. c Western blot of Pgp protein levels in MCF-7/KCR cells treated with 5 nm or 75 nm AgNPs. d Densitometric quantitation of Pgp western blots. Values are the means ± standard deviations of three independent experiments (****P < 0.0001, ns, non-significant, Fisher’s LSD test)