A nanofluidic immunoassay system to develop proteomic responsive biomarkers in non-small cell lung cancer.

27 Background: Molecular targeted therapy is widely used to treat non-small cell lung cancer (NSCLC). However, errors in predicting response to targeted therapies are 20-30%, based on sequencing or FISH, and patient specimen are at times not sufficient for conventional protein technologies. Developing clinically feasible proteomic biomarkers may be valuable to identify patients who may benefit from targeted therapy. Methods: NanoPro technology (ProteinSimple), is a capillary-based isoelectric-focusing (IEF) immunoassay system, which detects and quantifies multiple protein phosphorylation isoforms that are not readily assessed by traditional immunoassays. The platform only uses nanograms of protein for analysis. Results: We studied dynamic phosphoprotein activities in NSCLC cells (PC9, H827, H4006, H2122 and H322) treated with EGFR or/and MEK inhibitors. In MEK inhibitor (PD325901) treated cells, NanoPro showed that the drug efficiently inhibited Erk phosphorylation, and also revealed a complex MEK respons...