Kinomic profiling to predict sunitinib response of patients with metastasized clear cell Renal Cell Carcinoma.

Introduction: Treatment with Sunitinib, a potent multitargeted receptor tyrosine kinase inhibitor (TKI) has increased the progression-free survival (PFS) and overall-survival (OS) of patients with metastasized renal cell carcinoma (mRCC). With modest OS improvement and variable response and toxicity predictive and/or prognostic biomarkers are needed to personalize patient management: Prediction of individual TKI therapy response and resistance will increase successful treatment outcome while reducing unnecessary drug use and expense. The aim of this study was to investigate whether kinase activity analysis can predict sunitinib response and/or toxicity using tissue samples obtained from primary clear cell RCC (ccRCC) from a cohort of clinically annotated patients with mRCC receiving sunitinib as first-line treatment.

Peptide microarrays for profiling of serine/threonine kinase activity of recombinant kinases and lysates of cells and tissue samples.

Peptide microarray technology can be used to identify substrates for recombinant kinases, to measure kinase activity and changes thereof in cell lysates and lysates from fresh frozen (tumor) tissue. The effect of kinase inhibitors on the kinase activities in relevant tissues can be investigated as well. The method for performing experiments on dynamic peptide microarrays with real-time readout is described, as well as the influence of assay parameters and suggestions for optimization of experiments.

Peptide microarrays for detailed, high-throughput substrate identification, kinetic characterization, and inhibition studies on protein kinase A.

A microarray-based mix-and-measure, nonradioactive multiplex method with real-time detection was used for substrate identification, assay development, assay optimisation, and kinetic characterization of protein kinase A (PKA). The peptide arrays included either up to 140 serine/threonine-containing peptides or a concentration series of a smaller number of peptides. In comparison with existing singleplex assays, data quality was high, variation in assay conditions and reagent consumption were reduced considerably, and assay development could be accelerated because phosphorylation kinetics were monitored simultaneously on 4, 12, or 96 arrays.