Journal of Cell Science & Therapy
Open Access
ISSN: 2157-7013
+44 1300 500008
ISSN: 2157-7013
+44 1300 500008
Taosheng Chen
Scientific Tracks Abstracts: J Cell Sci Ther
Pregnane X receptor (PXR) is a broad-spectrum xenobiotic sensor and master transcriptional regulator of xenobiotic detoxifi cation and metabolism genes, capable of being activated by structurally diverse ligands, including many commercially marketed chemotherapeutics. Upon ligand engagement, PXR binds to the promoter regions of its target genes as a heterodimer with retinoic X receptor (RXR) to initiate gene transcription. Target genes of PXR include genes for phase I and phase II drug metabolizing enzymes and phase III ATP binding cassette drug transporters. Th e two most important target genes of PXR are cytochrome P450 3A4 (CYP3A4) and multidrug resistance 1 (MDR1). CYP3A4 is most abundantly expressed in the liver and is the primary contributor to metabolizing most of the currently marketed therapeutic agents. MDR1 is involved in drug resistance. Induction of CYP3A4 and MDR1 contributes to clinical drug- drug interactions and drug resistance. In addition, PXR carries out its non-genomic function through protein-protein interactions, and plays roles in many other important physiologic and pathologic processes, such as those in bone disorders, liver diseases, infl ammation, and cancers. Ligand-independent mechanisms, including post-translational modifi cations, also contribute to regulating PXR. I will discuss the regulation of PXR by phosphorylation, and by a novel PXR antagonist, and the implications in drug metabolism, drug resistance, and anti-cancer therapies.
Taosheng Chen is an Associate Member (Associate Professor) at St. Jude Children?s Research Hospital. His laboratory studies the function of nuclear receptors in drug metabolism, drug resistance, and tumorigenesis. He received his Ph.D. from the University of Vermont, and conducted postdoctoral studies at the University of Virginia. He has published more than 40 papers in reputed journals and serving as an editorial board member for 3 journals, and a book editor (http://www.stjuderesearch.org/chen/)