Quantification of ERK activity in cancer cell lysates and tumor extract using differential sensing methods

The activity of protein kinases in biological samples is typically estimated by determining the phosphorylation status of either the kinase itself, or a known cellular substrate. This is typically evaluated by multi-step western blotting, or proteomics procedures. Such procedures typically provide qualitative estimates of the modifications in question. While immunoblotting and proteomics procedures can be used in a quantitative manner, their complicated workflow diminishes reproducibility. Futhermore, modifications do not necessarily correlate closely with a protein kinase’s activity. The motivation for this work was to assess the potential of a peptide array to quantify ERK activity in cancer cell lines and tumor samples, without the need to suppress related kinase activities. This work shows that a library of cross-reactive peptide-based biosensors, along with chemometric analysis can be used to profile a kinase activity in cancer cell lines. Significantly, the array is suitable for quantifying unknown levels of ERK activity in unfractionated cancer cell lysates and tumor samples using a multivariate regression model. The predicted values provided by our model were found to be comparable to those obtained by immune complex kinase assays. Note: This abstract was not presented at the meeting. Citation Format: Diana Zamora-Olivares, Tamer S. Kaoud, Lingyu Zeng, Mitchell Telles, Eric V. Anslyn, Kevin N. Dalby. Quantification of ERK activity in cancer cell lysates and tumor extract using differential sensing methods [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 2172.