Two-dimensional gel electrophoresis: a powerful method to elucidate cellular responses to toxic compounds.

Humans are exposed to a variety of environmental toxicants and combinations thereof, and a large number of interacting factors contribute to an individual's risk for disease. Therefore, new strategies in toxicological research are needed for efficient screening of environmental hazards on complex living systems. The rapidly expanding field of proteomics relies heavily upon the use of two-dimensional gel electrophoresis (2-DE) of protein samples. 2-DE is a key separation technique in proteome analysis due to its advantage of simultaneous separation of thousands of proteins at a time, excellent reproducibility, and ability to exhibit post-translational modifications. Therefore, 2-D proteome analysis is becoming a popular method of choice to detect differentially expressed proteins between proteome profiles after exposure to toxicants. The goal of this study was to examine the response of pancreas carcinoma cells to increasing concentrations of the cytotoxic agent daunorubicin (DRC). The proteomic investigation revealed a number of proteins that were up-regulated by DRC treatment, some in a dose-dependent manner. However, these changes were not seen by reverse transcriptase-polymerase chain reaction. The determination of proteome changes following exposure to xenobiotics will aid our understanding of the mechanisms of their toxicity as well as providing the possibility for the establishment of biomarkers that can be used in risk assessment as well as for the identification of individual susceptibility factors.