title: Detection of aberrant protein phosphorylation in cancer using direct gold-protein affinity interactions.
abstract: Protein phosphorylation is one of the most prominent post-translational mechanisms for protein regulation, which is frequently impaired in cancer. Through the covalent addition of phosphate groups to certain amino-acids, the interactions of former residues with nearby amino-acids are drastically altered, resulting in major changes of protein conformation that impacts its biological function. Herein, we report that these conformational changes can also disturb the protein's ability to interact with and adsorb onto bare gold surfaces. We exploited this feature to develop a simple electrochemical method for detecting the aberrant phosphorylation of EGFR protein in several lung cancer cell lines. This method, which required as low as 10ng/µL (i.e., 50ng) of purified EGFR protein, also enabled monitoring cell sensitivity to tyrosine kinase inhibitors (TKI) - a common drug used for restoring the function of aberrantly phosphorylated proteins in lung cancer. The reported strategy based on direct gold-protein affinity interactions avoids the conventional paradigm of requiring a phospho-specific antibody for detection and could be a potential alternative of widely used mass spectrometry.
authors.affiliation: Centre for Personalized Nanomedicine, Australian Institute for Bioengineering and Nanotechnology (AIBN), The University of Queensland, Corner College and Cooper Roads (Bldg 75), Brisbane QLD 4072, Australia.
authors.forename: Mostak
authors.initials: M
authors.lastname: Ahmed
authors.affiliation: Centre for Personalized Nanomedicine, Australian Institute for Bioengineering and Nanotechnology (AIBN), The University of Queensland, Corner College and Cooper Roads (Bldg 75), Brisbane QLD 4072, Australia. Electronic address: lgcarrascosa@uq.edu.au.
authors.forename: Laura G
authors.initials: LG
authors.lastname: Carrascosa
authors.affiliation: Centre for Personalized Nanomedicine, Australian Institute for Bioengineering and Nanotechnology (AIBN), The University of Queensland, Corner College and Cooper Roads (Bldg 75), Brisbane QLD 4072, Australia.
authors.forename: Abu Ali
authors.initials: AA
authors.lastname: Ibn Sina
authors.affiliation: Centre for Personalized Nanomedicine, Australian Institute for Bioengineering and Nanotechnology (AIBN), The University of Queensland, Corner College and Cooper Roads (Bldg 75), Brisbane QLD 4072, Australia.
authors.forename: Ester Marina
authors.initials: EM
authors.lastname: Zarate
authors.affiliation: Centre for Personalized Nanomedicine, Australian Institute for Bioengineering and Nanotechnology (AIBN), The University of Queensland, Corner College and Cooper Roads (Bldg 75), Brisbane QLD 4072, Australia.
authors.forename: Darren
authors.initials: D
authors.lastname: Korbie
authors.affiliation: Centre for Personalized Nanomedicine, Australian Institute for Bioengineering and Nanotechnology (AIBN), The University of Queensland, Corner College and Cooper Roads (Bldg 75), Brisbane QLD 4072, Australia.
authors.forename: Ke-Lin
authors.initials: KL
authors.lastname: Ru
authors.affiliation: Centre for Personalized Nanomedicine, Australian Institute for Bioengineering and Nanotechnology (AIBN), The University of Queensland, Corner College and Cooper Roads (Bldg 75), Brisbane QLD 4072, Australia.
authors.forename: Muhammad J A
authors.initials: MJA
authors.lastname: Shiddiky
authors.affiliation: Centre for Personalized Nanomedicine, Australian Institute for Bioengineering and Nanotechnology (AIBN), The University of Queensland, Corner College and Cooper Roads (Bldg 75), Brisbane QLD 4072, Australia.
authors.forename: Paul
authors.initials: P
authors.lastname: Mainwaring
authors.affiliation: Centre for Personalized Nanomedicine, Australian Institute for Bioengineering and Nanotechnology (AIBN), The University of Queensland, Corner College and Cooper Roads (Bldg 75), Brisbane QLD 4072, Australia; School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane QLD 4072, Australia. Electronic address: m.trau@uq.edu.au.
authors.forename: Matt
authors.initials: M
authors.lastname: Trau
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation / Q000379:methods*; D045744:Cell Line, Tumor; D055664:Electrochemical Techniques / Q000295:instrumentation / Q000379:methods; D004867:Equipment Design; D066246:ErbB Receptors / Q000032:analysis* / Q000037:antagonists & inhibitors / Q000378:metabolism; D006046:Gold / Q000737:chemistry; D006801:Humans; D008168:Lung / Q000187:drug effects / Q000378:metabolism; D008175:Lung Neoplasms / Q000188:drug therapy / Q000378:metabolism*; D008958:Models, Molecular; D010766:Phosphorylation; D011487:Protein Conformation; D047428:Protein Kinase Inhibitors / Q000494:pharmacology
chemical_list: D047428:Protein Kinase Inhibitors; D006046:Gold; D066246:ErbB Receptors
keywords: EGFR protein; Electrochemistry; Gold-protein affinity; Protein phosphorylation; Tyrosine kinase inhibitor