title: Onconase mediated NFKβ downregulation in malignant pleural mesothelioma.
abstract: Treatment of malignant pleural mesothelioma (MPM) with Ranpirnase (Onconase) results in disruption of protein translation and cell apoptosis. We hypothesize that Onconase exerts an effect via downregulation of nuclear factor kappa B (NFKβ) by specific microRNAs (miRNAs) and that interference of this pathway could have implications for MPM resistance to chemotherapy. Three immortalized MPM cell lines (H2959, H2373 and H2591) were exposed to Onconase at 0-20 μg/ml. Cell counts were measured at 48 and 72 h. Gene expression in miRNA-enriched RNA was validated by reverse transcription-PCR (RT-PCR). The functional implications of miRNA expression were evaluated by transfecting miRNA mimics or inhibitors into MPM cell lines, and performing Matrigel invasion, cell proliferation, soft agar colony formation and scratch closure assays. Effects on NFKβ expression and downstream targets including ABC transporters, BCL-xl and IAP were assessed by RT-PCR and western blotting. Treatment with 20 μg/ml of Onconase significantly decreased cell count and invasion. Hsa-miR-17* was significantly upregulated and hsa-miR-30c was significantly downregulated by Onconase treatment in all cell lines. Forced expression of hsa-miR-17* mimic and hsa-miR-30c inhibitor each significantly decreased functional activity of Onconase in all assays. NFKB1 (p50) expression and downstream targets were also decreased with Onconase treatment, as well as with forced expression of miRNA mimic and inhibitors. Onconase treatment caused a significant decrease in cell proliferation, invasion and in expression of certain miRNAs. Recapitulation of the resultant miRNA expression pattern with hsa-miR-17* mimic and hsa-miR-30c inhibitor resulted in downregulation of NFKB1 and reduced malignant behavior in functional assays. Thus, Onconase likely exerts its antitumor effect through these miRNAs.
authors.affiliation: New York University Medical Center, Department of Cardiothoracic Surgery, New York, NY 10016, USA.
authors.forename: C M
authors.initials: CM
authors.lastname: Goparaju
authors.forename: J D
authors.initials: JD
authors.lastname: Blasberg
authors.forename: S
authors.initials: S
authors.lastname: Volinia
authors.forename: J
authors.initials: J
authors.lastname: Palatini
authors.forename: S
authors.initials: S
authors.lastname: Ivanov
authors.forename: J S
authors.initials: JS
authors.lastname: Donington
authors.forename: C
authors.initials: C
authors.lastname: Croce
authors.forename: M
authors.initials: M
authors.lastname: Carbone
authors.forename: H
authors.initials: H
authors.lastname: Yang
authors.forename: H I
authors.initials: HI
authors.lastname: Pass
mesh_terms: D018435:ATP Binding Cassette Transporter, Subfamily B; D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000235:genetics; D000970:Antineoplastic Agents / Q000494:pharmacology*; D045744:Cell Line, Tumor; D015536:Down-Regulation; D006801:Humans; D008654:Mesothelioma / Q000188:drug therapy* / Q000201:enzymology; D035683:MicroRNAs / Q000032:analysis / Q000502:physiology; D016328:NF-kappa B / Q000037:antagonists & inhibitors / Q000235:genetics* / Q000502:physiology; D010997:Pleural Neoplasms / Q000188:drug therapy* / Q000201:enzymology; D012260:Ribonucleases / Q000494:pharmacology*; D014162:Transfection
chemical_list: C513055:ABCB1 protein, human; D018435:ATP Binding Cassette Transporter, Subfamily B; D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D000970:Antineoplastic Agents; C524941:MIRN17 microRNA, human; D035683:MicroRNAs; D016328:NF-kappa B; D012260:Ribonucleases; C058703:ranpirnase