TY - JOUR T1 - Development of A Real-Time in Vivo Transcription Assay: Application Reveals Pregnane X Receptor-Mediated Induction of CYP3A4 by Cancer Chemotherapeutic Agents JF - Molecular Pharmacology JO - Mol Pharmacol SP - 439 LP - 445 DO - 10.1124/mol.62.3.439 VL - 62 IS - 3 AU - Erin Schuetz AU - Lubin Lan AU - Kazuto Yasuda AU - Richard Kim AU - Thomas A. Kocarek AU - John Schuetz AU - Stephen Strom Y1 - 2002/09/01 UR - http://molpharm.aspetjournals.org/content/62/3/439.abstract N2 - We report the development of a rapid real-time assay that measures the transcription of luciferase reporter genes in transduced mouse hepatic cells in vivo. Luciferase activity is noninvasively measured by whole-body optical imaging within hours of the hydrodynamic injection of as little as 1 μg of naked DNA. Transcription of genes introduced as linearized DNA can be serially assayed for weeks in each animal. Transcription was quantified by extracorporal monitoring of bioluminescence as well as or better than by traditional in vitro bioluminescence assay. Our assay allows the measurement of transcription as it occurs, under the most informative biological conditions (i.e., in a living, intact organ). Furthermore, it substantially reduces the cost, time, and number of animals required for analysis of gene expression. The utility of the method is demonstrated in the discovery that topotecan and etoposide are ligands of pregnane X receptor that induce CYP3A4 transcription. ER -