title: Identification of novel microRNAs regulating HLA-G expression and investigating their clinical relevance in renal cell carcinoma.
abstract: The non-classical human leukocyte antigen G (HLA-G) is expressed at a high frequency in renal cell carcinoma (RCC) and is associated with a higher tumor grade and a poor clinical outcome. This might be caused by the HLA-G-mediated inhibition of the cytotoxicity of T and NK cells. Therefore a selective targeting of HLA-G might represent a powerful strategy to enhance the immunogenicity of RCC lesions. Recent studies identified a number of HLA-G-regulating microRNAs (miRs) and demonstrated an inverse expression of some of these miRs with HLA-G in RCC in vitro and in vivo. However, it was postulated that further miRs might exist contributing to the tightly controlled selective HLA-G expression.By application of a miR enrichment assay (miTRAP) in combination with in silico profiling two novel HLA-G-regulatory miRs, miR-548q and miR-628-5p, were identified. Direct interactions of both miRs with the 3' untranslated region of HLA-G were confirmed with luciferase reporter gene assays. In addition, qPCR analyses and immunohistochemical staining revealed an inverse, expression of miR-628-5p, but not of miR-548q to the HLA-G protein in primary RCC lesions and cell lines. Stable overexpression of miR-548q and miR-628-5p caused a downregulation of HLA-G mRNA and protein. This leads in case of miR-548q to an enhanced NK cell-mediated HLA-G-dependent cytotoxicity, which could be reverted by ILT2 blockade suggesting a control of the immune effector cell activity at least by this miR. The identification of two novel HLA-G-regulatory miRs extends the number of HLA-G-relevant miRs tuning the HLA-G expression and might serve as future therapeutic targets.
authors.affiliation: Institute of Medical Immunology, Martin Luther University Halle-Wittenberg, Halle, Germany.
authors.forename: Simon
authors.initials: S
authors.lastname: Jasinski-Bergner
authors.affiliation: Faculty of Medicine, The Hebrew University of Jerusalem, Ein Kerem, Jerusalem, Israel.
authors.forename: Adi
authors.initials: A
authors.lastname: Reches
authors.affiliation: Institute of Pathology, Friedrich Alexander University Erlangen-Nuremberg, Erlangen, Germany.
authors.forename: Christine
authors.initials: C
authors.lastname: Stoehr
authors.affiliation: Institute of Medical Immunology, Martin Luther University Halle-Wittenberg, Halle, Germany.
authors.forename: Chiara
authors.initials: C
authors.lastname: Massa
authors.affiliation: Institute of Medical Immunology, Martin Luther University Halle-Wittenberg, Halle, Germany.
authors.forename: Evamaria
authors.initials: E
authors.lastname: Gonschorek
authors.affiliation: Institute of Molecular Medicine, Martin Luther University Halle-Wittenberg, Halle, Germany.
authors.forename: Stefan
authors.initials: S
authors.lastname: Huettelmaier
authors.affiliation: Institute of Molecular Medicine, Martin Luther University Halle-Wittenberg, Halle, Germany.
authors.forename: Juliane
authors.initials: J
authors.lastname: Braun
authors.affiliation: Clinic of Urology, Friedrich Alexander University Erlangen-Nuremberg, Erlangen, Germany.
authors.forename: Sven
authors.initials: S
authors.lastname: Wach
authors.affiliation: Clinic of Urology, Friedrich Alexander University Erlangen-Nuremberg, Erlangen, Germany.
authors.forename: Bernd
authors.initials: B
authors.lastname: Wullich
authors.affiliation: Faculty of Medicine, The Hebrew University of Jerusalem, Ein Kerem, Jerusalem, Israel.
authors.forename: Verena
authors.initials: V
authors.lastname: Spath
authors.affiliation: Sidra Medical and Research Center, Qatar Foundation, Doha, Qatar.
authors.forename: Ena
authors.initials: E
authors.lastname: Wang
authors.affiliation: Sidra Medical and Research Center, Qatar Foundation, Doha, Qatar.
authors.forename: Francesco M
authors.initials: FM
authors.lastname: Marincola
authors.affiliation: Faculty of Medicine, The Hebrew University of Jerusalem, Ein Kerem, Jerusalem, Israel.
authors.forename: Ofer
authors.initials: O
authors.lastname: Mandelboim
authors.affiliation: Institute of Pathology, Friedrich Alexander University Erlangen-Nuremberg, Erlangen, Germany.
authors.forename: Arndt
authors.initials: A
authors.lastname: Hartmann
authors.affiliation: Institute of Medical Immunology, Martin Luther University Halle-Wittenberg, Halle, Germany.
authors.forename: Barbara
authors.initials: B
authors.lastname: Seliger
mesh_terms: D014408:Biomarkers, Tumor / Q000032:analysis / Q000235:genetics; D002292:Carcinoma, Renal Cell / Q000235:genetics* / Q000378:metabolism; D020869:Gene Expression Profiling; D015972:Gene Expression Regulation, Neoplastic / Q000235:genetics*; D059951:HLA-G Antigens / Q000096:biosynthesis*; D006801:Humans; D007680:Kidney Neoplasms / Q000235:genetics; D035683:MicroRNAs / Q000235:genetics*; D059467:Transcriptome
chemical_list: D014408:Biomarkers, Tumor; D059951:HLA-G Antigens; C561887:MIRN548 microRNA, human; C000589022:MIRN628 microRNA, human; D035683:MicroRNAs
keywords: HLA-G; immune escape; microRNA; non-classical HLA class I molecules; renal cell carcinoma