RT Journal Article
SR Electronic
T1 Correlation Between Membrane Protein Concentrations and Transcellular Transport Activity for Breast Cancer Resistance Protein
JF Drug Metabolism and Disposition
JO Drug Metab Dispos
FD American Society for Pharmacology and Experimental Therapeutics
SP dmd.116.074245
DO 10.1124/dmd.116.074245
A1 Houfu Liu
A1 Liang Huang
A1 Yi Li
A1 Tingting Fu
A1 Xueying Sun
A1 Yan-Yan Zhang
A1 Ruina Gao
A1 Qingfang Chen
A1 Wandong Zhang
A1 Jasminder Sahi
A1 Scott Summerfield
A1 Kelly Dong
YR 2017
UL http://dmd.aspetjournals.org/content/early/2017/02/16/dmd.116.074245.abstract
AB Emerging evidence indicates an important role for breast cancer resistance protein (BCRP) in limiting brain penetration of substrate drugs. While in vitro Transwell® assays can provide an indication of BCRP substrate potential, the predictability of these to in vivo brain penetration is still under debate. The present study examines the correlation of BCRP protein concentration and transcellular transport activity across MDCKII monolayers. We expressed human BCRP or murine Bcrp1 in MDCKII wild-type cells using BacMam2 virus transduction. The selective P-glycoprotein (P-gp) inhibitor LY335979 (1 μM) was included in transport medium to measure BCRP-mediated transcellular transport for P-gp and BCRP co-substrates. BCRP protein levels in membrane extracts from MDCKII-BCRP or MDCKII-Bcrp1 cells were quantified by liquid chromatography-tandem mass spectrometry. The results are summarized as follows: 1) membrane protein concentrations correlates with corrected efflux ratios of substrates for human BCRP and murine Bcrp1 within the efflux ratios investigated; 2) we demonstrate a good concordance in rank order between BCRP and Bcrp1 mediated efflux ratios for 12 drugs; 3) we propose an approach to contextualize in vitro BCRP transport data of discovery compounds by comparing to the in vitro and in vivo transport data of reference drug dantrolene and taking into account inter-batch variation in BCRP protein expression. This approach correctly predicted compromised brain penetration for 22 proprietary discovery compounds in rodents, which were BCRP but not, or weak P-gp substrates. These results suggest that BCRP-expressing MDCKII cells are useful for predicting the in vivo role of BCRP in brain penetration.