Released on = June 21, 2007, 1:57 pm

Press Release Author = GTCbio

Industry = Biotech

Press Release Summary = Dr. John D. Haley, Translational Research at OSI
Pharmaceuticals Inc. will present on Enabling Technologies for Oncology Biomarker
Discovery at GTCbio's Rediscovering Biomarkers: Detection, Development & Validation
Conference taking place on July 23-24, 2007 at the San Diego Marriott La Jolla in La
Jolla, CA.

Press Release Body = Dr. John D. Haley, Translational Research at OSI
Pharmaceuticals Inc. will present on Enabling Technologies for Oncology Biomarker
Discovery at GTCbio's Rediscovering Biomarkers: Detection, Development & Validation
Conference taking place on July 23-24, 2007 at the San Diego Marriott La Jolla in La
Jolla, CA.

Human cancers demonstrate a multiplicity of signaling repertoires by which cell
survival and migration programs are achieved. Recent data highlight the conversion
of epithelial cancer cells to a more mesenchymal-like state, a process termed
epithelial-mesenchymal transition (EMT), to facilitate cell invasion and metastasis.
During epithelial to mesenchymal transition cells appear to acquire abnormal
EGFR-independent survival signals to escape cell death during detachment and
migration. We have employed overlapping technologies to measure signaling networks
within tumor cells with differing degrees of epithelial-mesenchymal transition.
These included quantitative measurements combining proteomic, gene expression,
confocal and immunoblot approaches. More specifically quantitative liquid
chromatography electrospray tandem mass spectrometry (LC-MS/MS) was employed to
measure protein and phosphoprotein abundance from specific tumor cell fractions.
Peptide sequence information ensured protein identification while stable isotope
labeling techniques allowed for protein quantitation. In one study, the relative
abundance of ~4000 proteins and phosphoproteins differentially measured between
epithelial and mesenchymal-like tumor states was measured. Marked decreases in
protein complexes associated with cell adhesion, cell-cell contact and cell polarity
were observed during EMT. mRNA and miRNA expression profiling using array and RT-PCR
approaches were compared with data obtained by proteomic approaches, confirming and
extending data obtained at the protein level. The localization of protein markers to
specific cellular or tissue compartments was achieved through confocal imaging and
compared with immunoblots of cell or tumor lysates to verify apparent protein
molecular weight. These technologies allowed us to define those signaling proteins
and pathways by which mesenchymal-like tumor cells bypass normal EGF receptor
dependence. From these efforts, tissue markers can be identified for the matching of
drug combinations, targeting the aberrant receptor signaling networks associated
with cell survival and cancer progression, with appropriate patients.

GTCbio's Rediscovering Biomarkers: Detection, Development & Validation Conference
provides comprehensive coverage of a wide range of topics including Biomarker
Application in Oncology Clinical Development, Drug Discovery, Development and
Diagnostics of Biomarkers, Tools for Improving Measurement, Safety and Validation of
Biomarkers, and Upcoming Technology and Trends.

For more information including a detailed agenda, exhibitor opportunities and
registration information visit
http://www.gtcbio.com/conference/conferenceDetails.aspx?id

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

Contact Details = 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, raniah@gtcbio.com