Taosheng Chen to Present at GTCbio’s 3rd Assay Development Conference, June 5-6

PR Log (Press Release) – Apr 01, 2008 – Dr. Taosheng Chen, Director of HTS, St. Jude Children's Research Hospital will present at GTCbio’s 3rd Assay Development & Screening Technologies Conference on June 5-6, 2008 in San Francisco, CA. Dr. Chen will speak on a chemical biology approach to identify modulators of xenobiotic receptor PXR.

Pregnane X receptor (PXR) has been established as a key xenobiotic receptor regulating metabolism and excretion of both xenobiotics and endobiotics. Two extremely important PXR-target genes are the cytochrome P450 3A4 (CYP3A4) and multidrug resistance 1 (MDR1)/P-glycoprotein (Pgp). CYP3A4 catalyzes the metabolism of nearly 60% of all clinically-prescribed drugs. MDR1 is an efflux transporter determining the absorption and elimination of many xenobiotics, including prescribed drugs. Changes in the expression of CYP3A4 and MDR1 can affect drug metabolism or elimination, thereby altering the therapeutic or toxicological response to a drug and possibly causing other adverse drug interactions, which are an important clinical problem and represent a major contributor to morbidity and mortality. A plethora of structurally diverse molecules, including some therapeutic drugs, directly bind to and activate PXR to induce the expression of CYP3A4 and MDR1. Additionally, many therapeutic drugs target signaling pathways that are involved in modulating PXR activation. Therefore, PXR functions not only as a xenobiotic sensor, but also as a site of integration of various signaling pathways. Using a chemical biology approach, we have identified small molecules that modulate PXR activation through various mechanisms. These mechanisms include direct receptor binding, or modulation of relevant signaling pathways that alter the response of PXR to its ligands. The development of assays and results from HTS, as well as the implication of these modulators in adverse drug-drug interactions, will be discussed.

GTCbio's 3rd Assay Development and Screening Technologies conference will provide attendees with critical information to utilize in the discovery and development of assays, while keeping them informed about the latest screening technologies for both high-throughput screening and high-content screening. Topics being covered include cell based assays, high throughput screening, high content screening, in vitro assays and screening, novel assay and screening technologies, and target validation. For more information visit www.gtcbio.com.