Pharmacodynamic Assay Panel for Monitoring Phospho-Signaling Networks

The DNA damage response (DDR) is a highly regulated signal transduction network that orchestrates the temporal and spatial organization of protein complexes required to repair (or tolerate) DNA damage (e.g., nucleotide excision repair, base excision repair, homologous recombination, non-homologous end joining, post-replication repair). Because the DDR network is a major defense system against environmental exposures linked to diseases, as well as a major target of somatic mutational inactivation in human cancers, being able to quantify and understand this variation has significant clinical and public health implications.

As a result, CPTAC researchers at the Fred Hutchinson Cancer Research Center (laboratory of Amanda Paulovich, MD, PhD) demonstrated the feasibility of using multiplex immuno-MRM for phospho-pharmacodynamic measurements, establishing the potential for rapid and precise quantification of cell signaling networks. A 69-plex immuno-MRM assay targeting the DNA damage response network was developed and characterized by response curves and determinations of intra- and inter-assay repeatability.

The study demonstrates the utility of multiplex immuno-MRM targeted assay panels for simultaneous quantification of phosphorylated and non-modified peptides, to support basic, clinical, and epidemiological studies.  The results of this study appeared online on May 18, 2015, in Molecular & Cellular Proteomics.

Research was supported by the National Cancer Institute of the National Institutes of Health Clinical Proteomic Tumor Analysis Consortium ( and Specialized Programs of Research Excellence (, and support by the Paul G. Allen Family Foundation (