ABSTRACT
We applied a novel profiling approach using receptor binding domain (RBD) ligands to cell surface domains of a panel of nutrient transporters to characterize the impact of a number of tyrosine kinase inhibitor anticancer drugs on human stem cell-derived cardiomyocytes. High-content screening and flow cytometry analysis showed diagnostic changes in nutrient transporter expression correlating with glycolysis and oxidative phosphorylation-based cell metabolism in glucose and galactose media. Cluster analysis of RBD binding signatures of drug-treated cells cultured in glucose medium showed good correlation with sensitization of mitochondrial toxicity in cells undergoing oxidative phosphorylation in galactose medium. These data demonstrate the potential for RBD ligands as profiling tools to improve the clinical predictivity of in vitro cell assays for drug toxicity.
Subject(s)
Antineoplastic Agents/pharmacology , Carrier Proteins/metabolism , Myocytes, Cardiac/radiation effects , Protein Kinase Inhibitors/pharmacology , Protein-Tyrosine Kinases/antagonists & inhibitors , Binding Sites , Cells, Cultured , Drug Screening Assays, Antitumor/methods , Flow Cytometry , Glucose Transporter Type 1/metabolism , Humans , Ligands , Myocytes, Cardiac/metabolism , Oxidative Phosphorylation/drug effects , Protein Domains , Protein-Tyrosine Kinases/metabolism , Stem Cells/cytology , Toxicity Tests/methodsABSTRACT
The use of stable cell lines expressing fusions with green fluorescent protein (GFP) has increased significantly in recent years. In this study we have used a range of complimentary analytical techniques to examine the characteristics of a cell line stably expressing a EGFP cell cycle sensor relative to parental U2OS cells. Analysis of cell cycle duration and cell cycle phase distribution by cell growth assays and flow cytometry revealed that the two cell lines had identical doubling times and cell cycle distributions. Measurement of EGFP fusion protein mRNA by quantitative RT-PCR indicated a EGFP sensor expression level equivalent to endogenous Cyclin B1 (7000 copies/cell in G2). Microarray analysis showed a 0.9% (>2 fold at p<0.001 across 20,000 genes) difference in global gene expression levels between parental and EGFP expressing U2OS cells, with no significant differences in expression of A, B, C, D, E, F, G, H, I, K, L, M or T type Cyclins between the two cell types. These results confirm that engineering a stable cell line for low expression of a EGFP cell cycle sensor is minimally perturbing to the cell cycle and cellular gene expression.
