Fig. 1.

Drug-resistant SKOV3 ovarian and MCF7 breast tumor models. Expression of the MDR marker proteins P-glycoprotein and glucosylceramide synthase in SKOV3_TR and MCF_TR cells as compared with their wild-type cell lines a in culture observed by Western blot (beta-actin serves as an internal control) and b in xenografted tumor cross sections observed by immunohistochemistry (brown staining indicates the presence of P-glycoprotein or CS in the tumor tissue, while blue (haematoxylin) counterstaining indicate the absence of protein; ×200 original magnification)