Large-Scale Transcriptional Profiling of Molecular Perturbations Reveals Cell Type Specific Responses and Implications for Environmental Screening

Cell-based assays represent nearly half of all high-throughput screens currently conducted for risk assessment of environmental chemicals. However, the sensitivity and heterogeneity among cell lines has long been concerned but explored only in a limited manner. Here, we address this question by conducting a large scale transcriptomic analysis of the responses of discrete cell lines to specific small molecules. Our results illustrate heterogeneity of the extent and timing of responses among cell lines. Interestingly, high sensitivity and/or heterogeneity was found to be cell type-specific or universal depending on the different mechanism of actions of the compounds. Our data provide a novel insight into the understanding of cell-small molecule interactions and have substantial implications for the design, execution and interpretation of high-throughput screening assays.