title: Complete reversal of ABCG2-depending atypical multidrug resistance by RNA interference in human carcinoma cells.
abstract: In the chemotherapeutic treatment of patients with disseminated neoplasms, multidrug resistance (MDR) is a major obstacle. ABCG2 (BCRP/MXR), a member of the superfamily of adenosine triphosphate-binding cassette (ABC) transporters, was demonstrated to be associated with "atypical" forms of multidrug-resistant phenotypes of cancer cells. To overcome the ABCG2-depending MDR, two specific anti-ABCG2 small interfering RNAs (siRNAs) were designed for transient triggering of the gene-silencing RNA interference (RNAi) pathway in the human gastric carcinoma cell line EPG85-257RNOV, exhibiting an atypical MDR phenotype. Because both siRNAs showed biological activity, for stable inhibition of ABCG2 corresponding short hairpin RNA (shRNA) expression vectors were constructed. By treatment of EPG85-257RNOV cells with these constructs, expression of the targeted ABCG2-encoding mRNA and transport protein was inhibited completely. Furthermore, anti-ABCG2 shRNA-treated cells increased cellular drug accumulation to the same level measured in drug-sensitive parental cells. These effects were accompanied by complete reversal of the drug-resistant phenotype. Thus, the data indicate that siRNA- and shRNA-mediated RNAi-based gene therapy may be applicable in preventing and reversing ABCG2-depending atypical MDR.
authors.affiliation: Charité Campus Mitte, Institute of Pathology, D-10117 Berlin, Germany.
authors.forename: Axel
authors.initials: A
authors.lastname: Priebsch
authors.forename: Franziska
authors.initials: F
authors.lastname: Rompe
authors.forename: Holger
authors.initials: H
authors.lastname: Tönnies
authors.forename: Petra
authors.initials: P
authors.lastname: Kowalski
authors.forename: Pawel
authors.initials: P
authors.lastname: Surowiak
authors.forename: Alexandra
authors.initials: A
authors.lastname: Stege
authors.forename: Verena
authors.initials: V
authors.lastname: Materna
authors.forename: Hermann
authors.initials: H
authors.lastname: Lage
mesh_terms: D000070997:ATP Binding Cassette Transporter, Subfamily G, Member 2; D018528:ATP-Binding Cassette Transporters / Q000037:antagonists & inhibitors / Q000235:genetics / Q000502:physiology*; D002277:Carcinoma / Q000378:metabolism*; D045744:Cell Line, Tumor; D019008:Drug Resistance, Neoplasm / Q000235:genetics*; D006801:Humans; D009363:Neoplasm Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000502:physiology*; D034622:RNA Interference / Q000502:physiology*; D012333:RNA, Messenger / Q000037:antagonists & inhibitors; D034741:RNA, Small Interfering / Q000502:physiology*; D013274:Stomach Neoplasms / Q000378:metabolism*; D014407:Tumor Cells, Cultured
chemical_list: C116614:ABCG2 protein, human; D000070997:ATP Binding Cassette Transporter, Subfamily G, Member 2; D018528:ATP-Binding Cassette Transporters; D009363:Neoplasm Proteins; D012333:RNA, Messenger; D034741:RNA, Small Interfering