Down-Regulation of ATP-Binding Cassette C2 Protein Expression in HepG2 Cells after Rifampicin Treatment Is Mediated by MicroRNA-379

Abstract

microRNAs (miRNAs), which contribute to the post-transcriptional processing through 3Ј-untranslated region-interference, have been shown to be involved in the regulation of ATPbinding cassette (ABC) membrane transporters. The aim of this study was to investigate whether ABCC2, an important efflux transporter for various endogenous and exogenous compounds at several compartment barriers, is subject to miRNAmediated post-transcriptional gene regulation. We screened the expression of 377 human miRNAs in HepG2 cells after 48 h of treatment with 5 M rifampicin [a pregnane X receptor (PXR) ligand] or vehicle using reverse transcription-polymerase chain reaction-based low-density arrays. Specific miRNA, ABCC2 mRNA, and protein expression were monitored in HepG2 cells undergoing rifampicin treatment for 72 h. Loss-and gain-offunction experiments and reporter gene assays were performed for further confirmation. Highly deregulated miRNAs compared with in silico data revealed miRNA (miR) 379 as candidate miRNA targeting ABCC2 mRNA. Under rifampicin treatment, ABCC2 mRNA increased significantly, with a maximal fold change of 1.56 Ϯ 0.43 after 24 h. In addition, miR-379 increased (maximally 4.10 Ϯ 1.33-fold after 48 h), whereas ABCC2 protein decreased with a maximal fold change of 0.47 Ϯ 0.08 after 72 h. In contrast, transfection of miR-379 inhibitor led to an elevation of ABCC2 protein expression after rifampicin incubation for 48 h. We identify a miRNA negatively regulating ABCC2 on the post-transcriptional level and provide evidence that this miRNA impedes overexpression of ABCC2 protein after a PXR-mediated external transcriptional stimulus in HepG2 cells.

MicroRNA Pharmacoepigenetics: Posttranscriptional Regulation Mechanisms behind Variable Drug Disposition and Strategy to Develop More Effective Therapy

“…The reduction of ABCC2 protein expression by rifampicin in HepG2 cells was associated with an increased ABCC2 mRNA level and altered miRNA expression profile (Haenisch et al, 2011). Among these altered miRNAs, miR-379 was elevated and might directly target ABCC2 mRNA.…”

“…Among these altered miRNAs, miR-379 was elevated and might directly target ABCC2 mRNA. Indeed pre-miR-379 showed a dose-dependent suppression of ABCC2 protein expression in HepG2 cells, and miR-379 antagomir was able to rescue rifampicin-reduced ABCC2 protein expression, demonstrating a mechanistic role for miR-379 in rifampicin-altered ABCC2 protein expression at the posttranscriptional level (Haenisch et al, 2011). Another study showed that miR-297 was able to modulate ABCC2 expression in drug-resistant HCT116 cells and thus increased the efficacy of anticancer drugs (Xu et al, 2012a).…”

Characterization of SLC transporters in human skin

“…Previous studies showed that treatment with rifampicin decreased the expression level of ABCC1 (MRP1) in human skin [17] and in HepG2 cells [24]. The effect of rifampicin on the expression of SLC transporters was thus investigated.…”

Chimeric MicroRNA-1291 Biosynthesized Efficiently in Escherichia coli Is Effective to Reduce Target Gene Expression in Human Carcinoma Cells and Improve Chemosensitivity

“…Some miRNAs (e.g., miR-519c, -328, -326, -379, -1291, and -124) Pan et al, 2009Pan et al, , 2013Liang et al, 2010;Haenisch et al, 2011;Markova and Kroetz, 2014) that negatively regulate the expression of ATP-binding cassette efflux transporters (e.g., ABCC1, ABCC2, ABCC4, and ABCG2) may be used to improve the sensitivity of human carcinoma cells to anticancer drugs. Furthermore, a number of oncogenic miRNAs dysregulated in tumor tissues may be directly targeted to manage tumor progression (Trang et al, 2008;Bader et al, 2010).…”