Drug Metabolism and Toxicology, Faculty of Pharmaceutical Sciences, Kanazawa University, Kakuma-machi, Kanazawa, 920-1192, Japan; WPI Nano Life Science Institute (WPI-NanoLSI) Kanazawa University, Kakuma-machi, Kanazawa, 920-1192, Japan.
Drug Metabolism and Toxicology, Faculty of Pharmaceutical Sciences, Kanazawa University, Kakuma-machi, Kanazawa, 920-1192, Japan.
Drug Metab Pharmacokinet. 2021 Jun;38:100388. doi: 10.1016/j.dmpk.2021.100388. Epub 2021 Mar 10.
Human hepatic cytochrome P450 2B6 (CYP2B6) expressed is responsible for the metabolism of many drugs, such as cyclophosphamide, ifosfamid, and efavirenz. In the present study, the correlation between CYP2B6 mRNA and protein levels in human liver samples was found to be moderate, indicating a contribution of posttranscriptional regulation of CYP2B6. Thus, we examined the role of microRNAs (miRNAs) in the regulation of CYP2B6. We established two kinds of HEK293 cell lines stably expressing CYP2B6, including or excluding the full-length 3'-untranslated region (3'-UTR) (HEK/2B6+UTR and HEK/2B6 cells, respectively). We tested 14 miRNAs that were predicted to bind to the 3'-UTR of CYP2B6 and found that the overexpression of miR-145, miR-194, miR-222, and miR-378 decreased the CYP2B6 protein level and activity in HEK/2B6+UTR but not in HEK/2B6 cells. These results suggested that miR-145, miR-194, miR-222, and miR-378 negatively regulate CYP2B6 expression by binding to the 3'-UTR. A negative correlation was not observed between the translational efficiency of CYP2B6 and the expression level of miR-145, miR-194, miR-222, or miR-378. This is due to the contribution of multiple miRNAs to CYP2B6 regulation. In conclusion, this study demonstrated that human CYP2B6 is posttranscriptionally regulated by miR-145, miR-194, miR-222, and miR-378.
人肝细胞色素 P450 2B6（CYP2B6）表达负责代谢许多药物，如环磷酰胺、异环磷酰胺和依非韦伦。在本研究中，发现人肝组织样本中 CYP2B6 mRNA 和蛋白水平之间存在中度相关性，表明 CYP2B6 的转录后调控发挥了作用。因此，我们研究了 microRNAs（miRNAs）在 CYP2B6 调控中的作用。我们建立了两种稳定表达 CYP2B6 的 HEK293 细胞系，包括包含全长 3'-非翻译区（3'-UTR）（HEK/2B6+UTR 和 HEK/2B6 细胞）和不包含全长 3'-UTR 的 CYP2B6（HEK/2B6 细胞）。我们测试了 14 种被预测能与 CYP2B6 3'-UTR 结合的 miRNAs，发现 miR-145、miR-194、miR-222 和 miR-378 的过表达降低了 HEK/2B6+UTR 中的 CYP2B6 蛋白水平和活性，但在 HEK/2B6 细胞中没有。这些结果表明，miR-145、miR-194、miR-222 和 miR-378 通过与 3'-UTR 结合负调控 CYP2B6 的表达。CYP2B6 的翻译效率与 miR-145、miR-194、miR-222 或 miR-378 的表达水平之间没有观察到负相关性。这是由于多个 miRNAs 对 CYP2B6 调节的贡献。总之，本研究表明人类 CYP2B6 受 miR-145、miR-194、miR-222 和 miR-378 的转录后调控。
