Released on: March 28, 2008, 4:52 pm

Press Release Author: GTCbio

Industry: Biotech

Press Release Summary: 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.


Press Release Body: 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.
ABOUT GTCbio
GTCbio organizes conferences specifically for the biomedical and biopharmaceutical
industries. Our goal is to facilitate the exchange of biopharmaceutical and
biomedical intelligence between industry leaders, academic and government
organizations, and the financial community.
GTCbio is a subsidiary of Global Technology Community, LLC, a privately held company
founded in 2002.
Contact: GTCBIO (626) 256-6405, (626) 256-6460 fax, nina.tran@gtcbio.com




Web Site: http://www.gtcbio.com

Contact Details: Contact: GTCBIO (626) 256-6405, (626) 256-6460 fax,
nina.tran@gtcbio.com

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