Selective inhibition of MDR1 (ABCB1) by HM30181 increases oral bioavailability and therapeutic efficacy of paclitaxel.

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Citation

Kwak JO, Lee SH, Lee GS, Kim MS, Ahn YG, Lee JH, Kim SW, Kim KH, Lee MG

Selective inhibition of MDR1 (ABCB1) by HM30181 increases oral bioavailability and therapeutic efficacy of paclitaxel.

Eur J Pharmacol. 2010 Feb 10;627(1-3):92-8. doi: 10.1016/j.ejphar.2009.11.008. Epub 2009 Nov 10.

PubMed ID
19903471 [ View in PubMed
]
Abstract

Multi-drug resistance 1 (MDR1, ABCB1), also known as P-glycoprotein (P-gp), restricts intestinal uptake of many drugs, and contributes to cellular resistance to cancer chemotherapy. In this study, we examined the pharmacologic characteristics of HM30181, a newly developed MDR1 inhibitor, and tested its capacity to increase the oral bioavailability and efficacy of paclitaxel, an anti-cancer drug usually given by intravenous injection. In the ATPase assay using MDR1-enriched vesicles, HM30181 showed the highest potency (IC(50)=0.63nM) among several MDR1 inhibitors, including cycloporin A, XR9576, and GF120918, and effectively blocked transepithelial transport of paclitaxel in MDCK monolayers (IC(50)=35.4nM). The ATPase inhibitory activity of HM30181 was highly selective to MDR1. HM30181 did not inhibit MRP1 (ABCC1), MRP2 (ABCC2), and MRP3 (ABCC3), and partially inhibited BCRP (ABCG2) only at very high concentrations. Importantly, co-administration of HM30181 (10mg/kg) greatly increased oral bioavailability of paclitaxel from 3.4% to 41.3% in rats. Moreover, oral co-administration of paclitaxel and HM30181 showed a tumor-inhibitory strength equal or superior to that of intravenous paclitaxel in the xenograft model in nude mice. These results identify HM30181 as a highly selective and potent inhibitor of MDR1, which in combination with paclitaxel, may provide an orally effective anti-tumor regimen.

DrugBank Data that Cites this Article

Drug Transporters
DrugTransporterKindOrganismPharmacological ActionActions
PaclitaxelP-glycoprotein 1ProteinHumans
Unknown
Substrate
Inhibitor
Details