p-glycoprotein (p-gp) is a trans-membrane drug efflux pump. several drugs are p-gp substrates. some drugs may affect the activity of p-gp by inhibiting its function, resulting in significant drug-drug interactions (ddis). it is critical to understand which drugs are inhibitors of p-gp so that adverse ddis can be minimized or avoided. this study investigated the effects of gliclazide, metformin,...

In the past years, the development of oral formulations of the taxane anticancer drugs paclitaxel (Taxol ®) and docetaxel (Taxotere ®) has been the focus of preclinical and clinical research in our groups. A major limitation in the concept of oral administration of paclitaxel and docetaxel is their low oral availability [1]. Paclitaxel and docetaxel have poor aqueous solubility and upon oral ad...

P-Glycoprotein (P-GP) plays a pivotal role in maintaining the multidrug-resistant (MDR) phenotype. This membrane glycoprotein is overproduced in MDR cells and the endometrium of the mouse gravid uterus (Arceci, R.J., Croop, J.M., Horwitz, S.B., and Housman, D. (1988) Proc. Natl. Acad. Sci. U.S.A. 85, 4350-4354). This latter observation and an interest in endogenous substrates for P-GP led to a ...

conclusions verapamil and rifampin were found specific and effective against p-gp expression in hcc. in conclusion, treatment efficacy of most anticancer drugs is increased in combination with verapamil and rifampin against most advanced hcc. objectives the aim of this study was to elucidate the effect of potent carcinogen nitrosamine with and without verapamil and rifampin drugs on p-gp expres...

Compounds known to modulate P-glycoprotein (P-gp) activity were evaluated in cell monolayers expressing P-gp for their effects on the secretory transport of P-gp substrates paclitaxel, vinblastine, and digoxin. Paclitaxel has been proposed to selectively interact with a binding site on P-gp that is distinct from the vinblastine and digoxin-binding site. Using Madin-Darby canine kidney (MDCK)-mu...

P-glycoprotein (P-gp) is encoded by the multidrug resistance (MDR1) gene and is well studied as a multi-drug resistance transporter. Peritoneal adhesion formation following abdominal surgery remains an important clinical problem. Here, we found that P-gp was highly expressed in human adhesion fibroblasts and promoted peritoneal adhesion formation in a rodent model. Knockdown of P-gp expression ...

P-glycoprotein (P-gp) is a membranous ATPase responsible for the multidrug resistance (MDR) phenotype. Using membrane vesicles prepared from the highly resistant cell line DC-3F/ADX we studied the influence of P-gp ATPase activity of four progesterone derivatives which specifically bind to P-gp and reverse MDR. Progesterone and desoxycorticosterone stimulate P-gp ATPase activity with, respectiv...

The human MDR1-encoded transporter is a 170-kDa plasma membrane glycoprotein [P-glycoprotein (P-gp)] capable of binding and energy-dependent extrusion of structurally diverse organic compounds and drugs. P-gp seems to play a significant role in uptake, distribution, and excretion of many different drugs. To determine whether common polymorphic forms of P-gp are likely to alter function of P-gp,...

A sensitive immunocytochemical technique was developed to detect a 170,000 dalton cell membrane glycoprotein (P-gp) in cell lines resistant to vincristine and vinblastine with varying degrees of resistance. P-gp was shown very clearly using the C219 monoclonal antibody and immunocytochemical detection with either antialkaline phosphate or peroxidase-antiperoxidase with silver gold intensificati...

We propose that the cellular burden of certain carcinogens may be mitigated by P-glycoprotein (P-gp), the putative drug efflux pump. In a series of multidrug resistant human breast cancer MCF-7 cells with increasing P-gp expression we examined this hypothesis using benzo(alpha)pyrene, a widely distributed environmental and dietary carcinogen. We found that multidrug resistant cells were cross-r...