International Congress on Advances in BioScience and Biotechnology, Sarajevo, Bosnia And Herzegovina, 25 - 29 October 2017, pp.59
Most of the marketed drugs are metabolized by Cytochrome P450s (CYPs) known as phase I enzymes. A phase I enzyme, CYP1A1 catalyzes the conversion of many pro-carcinogens and hydroxylation of many endogenous substrates. CYP2E1 is also important in the metabolism of drugs, pre-toxins and pro-carcinogens. The present study was aimed to describe the best cell line model for studying phase I xenobiotic metabolizing CYP1A1 and CYP2E1 enzymes and possible effects of xenobiotics on these enzymes. In this study HT29 and SW620 (colon); HEPG2 and HUH7 (liver); PNT1A and PC3 (prostate) cell lines were chosen. Then, mRNA and protein expressions of the CYP1A1 and CYP2E1 enzymes in these cell lines were analyzed by qRT-PCR and Western blotting techniques, respectively. It has been found that CYP1A1 protein was expressed in all cell lines and relative protein expression is highest in the HT29 (100%). In addition, HEPG2 (0.63 fold) and HUH7 (1 fold) expressed highest CYP1A1 mRNA. CYP2E1 protein expression was found in all cell lines at relatively high levels except PC3. CYP2E1 mRNA expression was significantly higher in HUH7 (1 fold) and HT29 (0.59 fold). According to the results, there was no significant correlation between mRNA and protein expressions. Thus choosing the best cell line as model depends on the purpose of the research. For studying metabolism of a chemical by CYP1A1 and CYP2E1 or effect of a chemical on translational regulation of these enzymes, it is better to consider protein expression levels. However, if the aim is to study effect of a chemical on transcriptional regulation of these enzymes, it is better to choose a cell line that expressing highest mRNA of gene of interest. Considering both mRNA and protein expression levels together, the best model cell lines for studying CYP1A1 and CYP2E1 are HT29 and HUH7, respectively.