title: Small interfering RNA-induced suppression of MDR1 (P-glycoprotein) restores sensitivity to multidrug-resistant cancer cells.
abstract: Overexpression of P-glycoprotein (P-gp), the MDR1 gene product, confers multidrug resistance (MDR) to cancer cells. Clinically, MDR is one of the major causes for chemotherapeutic treatment failure in cancer patients. To explore a new approach to circumventing MDR, we adopted RNA interference to target MDR1 gene expression. RNA interference is a conserved biological response to double-stranded RNA, which results in sequence-specific gene silencing [G. J. Hannon, Nature (Lond.), 418: 244-251, 2002]. We report that introduction of an MDR1-targeted small interfering RNA duplex into drug-resistant cancer cells markedly inhibited the expression of MDR1 mRNA and P-gp, as determined by reverse transcription-PCR and Western blot. Inhibition of P-gp expression by small interfering RNA enhanced the intracellular accumulation of and selectively restored sensitivity to drugs transported by P-gp. These studies indicate that RNA interference can modulate MDR in preclinical models.
authors.affiliation: Department of Pharmacology, University of Medicine and Dentistry of New Jersey/Robert Wood Johnson Medical School, New Brunswick, New Jersey 08901, USA.
authors.forename: Hao
authors.initials: H
authors.lastname: Wu
authors.forename: William N
authors.initials: WN
authors.lastname: Hait
authors.forename: Jin-Ming
authors.initials: JM
authors.lastname: Yang
mesh_terms: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000037:antagonists & inhibitors* / Q000096:biosynthesis / Q000235:genetics; D000970:Antineoplastic Agents / Q000493:pharmacokinetics / Q000494:pharmacology; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000235:genetics / Q000378:metabolism; D004317:Doxorubicin / Q000493:pharmacokinetics / Q000494:pharmacology; D018432:Drug Resistance, Multiple / Q000235:genetics*; D019008:Drug Resistance, Neoplasm; D004354:Drug Screening Assays, Antitumor; D015972:Gene Expression Regulation, Neoplastic / Q000235:genetics; D019450:Genes, MDR / Q000235:genetics*; D006801:Humans; D017239:Paclitaxel / Q000493:pharmacokinetics / Q000494:pharmacology; D034741:RNA, Small Interfering / Q000008:administration & dosage / Q000235:genetics*; D014162:Transfection; D014407:Tumor Cells, Cultured; D014747:Vinblastine / Q000493:pharmacokinetics / Q000494:pharmacology
chemical_list: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D000970:Antineoplastic Agents; D034741:RNA, Small Interfering; D014747:Vinblastine; D004317:Doxorubicin; D017239:Paclitaxel