NextGen Sciences, specialists in providing discovery, assay development, and testing services, and Expression Pathology, Inc., a leader in tissue protein analysis, have developed a protein biomarker assay methodology that provides, for the first time, rapid, reproducible, quantitative measurement of protein expression in formalin fixed paraffin embedded (FFPE) tissue samples.
The assay methodology uses Expression Pathology’s Liquid Tissue reagents and protocols for sample preparation and to solubilize the entire protein content from standard FFPE tissue. The solubilized proteins are then assayed by NextGen Sciences using Multiple Reaction Monitoring (MRM), a method for quantitation of proteins using mass spectrometry. The results correlate directly with those obtained by current immunohistochemistry techniques, but the new method is faster, straightforward, and provides accurate and quantitative measurement of protein biomarkers.
The companies began collaborating in June 2008, and have demonstrated the utility of the FFPE MRM assay methodology by measurement of the Her2 protein, which has become an important marker for breast cancer diagnosis and therapy. Formalin fixation of tissue samples which are subsequently embedded in paraffin is the gold standard for biopsy and surgical tissue preservation. However, proteins within the tissue samples are heavily cross-linked as a result of the formalin fixation and therefore, until now, options for analyzing them have been limited.
This assay shows that FFPE tissue can be used for direct measurement of clinically important protein biomarkers by mass-spectrometry-based protocols. As MRM assays can be multiplexed, there is the potential to develop assays where multiple proteins are measured simultaneously, like cancer therapy targets or cell signalling pathway proteins.
Her2 is the prototype diagnostic, prognostic and therapeutic target for the personalized medicine approach to disease treatment. Precise quantitation of such protein biomarkers in FFPE tissue may have a major impact on the advancement of personalized medicine.
NextGen Sciences
Expression Pathology, Inc.
