TY - JOUR
T1 - Identification of inhibitors of ABCG2 by a bioluminescence imaging-based high-throughput assay
AU - Zhang, Yimao
AU - Byun, Youngjoo
AU - Ren, Yunzhao R.
AU - Liu, Jun O.
AU - Laterra, John
AU - Pomper, Martin G.
PY - 2009/7/15
Y1 - 2009/7/15
N2 - ABCG2 is a member of the ATP-binding cassette (ABC) family of transporters, the overexpression of which is associated with tumor resistance to a variety of chemotherapeutic agents. Accordingly, combining ABCG2 inhibitor(s) with chemotherapy has the potential to improve treatment outcome. To search for clinically useful ABCG2 inhibitors, a bioluminescence imaging (BLI)-based assay was developed to allow highthroughput compound screening. This assay exploits our finding that D-luciferin, the substrate of firefly luciferase ( fLuc), is a specific substrate of ABCG2, and ABCG2 inhibitors block the export of D-luciferin and enhance bioluminescence signal by increasing intracellular D-luciferin concentrations. HEK293 cells, engineered to express ABCG2 and fLuc, were used to screen the Hopkins Drug Library that includes drugs approved by the Food and Drug Administration (FDA) as well as drug candidates that have entered phase II clinical trials. Forty-seven compounds showed BLI enhancement, a measure of anti-ABCG2 activity, of z5-fold, the majority of which were not previously known as ABCG2 inhibitors. The assay was validated by its identification of known ABCG2 inhibitors and by confirming previously unknown ABCG2 inhibitors using established in vitro assays (e.g., mitoxantrone resensitization and BODIPY-prazosin assays). Glafenine, a potent new inhibitor, also inhibited ABCG2 activity in vivo. The BLI-based assay is an efficient method to identify newinhibitors of ABCG2. As they were derived from a FDA-approved compound library, many of the inhibitors uncovered in this study are ready for clinical testing.
AB - ABCG2 is a member of the ATP-binding cassette (ABC) family of transporters, the overexpression of which is associated with tumor resistance to a variety of chemotherapeutic agents. Accordingly, combining ABCG2 inhibitor(s) with chemotherapy has the potential to improve treatment outcome. To search for clinically useful ABCG2 inhibitors, a bioluminescence imaging (BLI)-based assay was developed to allow highthroughput compound screening. This assay exploits our finding that D-luciferin, the substrate of firefly luciferase ( fLuc), is a specific substrate of ABCG2, and ABCG2 inhibitors block the export of D-luciferin and enhance bioluminescence signal by increasing intracellular D-luciferin concentrations. HEK293 cells, engineered to express ABCG2 and fLuc, were used to screen the Hopkins Drug Library that includes drugs approved by the Food and Drug Administration (FDA) as well as drug candidates that have entered phase II clinical trials. Forty-seven compounds showed BLI enhancement, a measure of anti-ABCG2 activity, of z5-fold, the majority of which were not previously known as ABCG2 inhibitors. The assay was validated by its identification of known ABCG2 inhibitors and by confirming previously unknown ABCG2 inhibitors using established in vitro assays (e.g., mitoxantrone resensitization and BODIPY-prazosin assays). Glafenine, a potent new inhibitor, also inhibited ABCG2 activity in vivo. The BLI-based assay is an efficient method to identify newinhibitors of ABCG2. As they were derived from a FDA-approved compound library, many of the inhibitors uncovered in this study are ready for clinical testing.
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U2 - 10.1158/0008-5472.CAN-08-4866
DO - 10.1158/0008-5472.CAN-08-4866
M3 - Article
C2 - 19567678
AN - SCOPUS:67651000082
SN - 0008-5472
VL - 69
SP - 5867
EP - 5875
JO - Cancer Research
JF - Cancer Research
IS - 14
ER -