title: Increased miR-155-5p and reduced miR-148a-3p contribute to the suppression of osteosarcoma cell death.
abstract: Osteosarcoma (OS) is the most common cancer of bone and the 5th leading cause of cancer-related death in young adults. Currently, 5-year survival rates have plateaued at ~70% for patients with localized disease. Those with disseminated disease have an ~20% 5-year survival. An improved understanding of the molecular genetics of OS may yield new approaches to improve outcomes for OS patients. To this end, we applied murine models that replicate human OS to identify and understand dysregulated microRNAs (miRNAs) in OS. miRNA expression patterns were profiled in murine primary osteoblasts, osteoblast cultures and primary OS cell cultures (from primary and paired metastatic locations) isolated from two genetically engineered murine models of OS. The differentially expressed miRNA were further assessed by a cross-species comparison with human osteoblasts and OS cultures. We identified miR-155-5p and miR-148a-3p as deregulated in OS. miR-155-5p suppression or miR-148a-3p overexpression potently reduced proliferation and induced apoptosis in OS cells, yet strikingly, did not impact normal osteoblasts. To define how these miRNAs regulated OS cell fate, we used an integrated computational approach to identify putative candidate targets and then correlated these with the cell biological impact. Although we could not resolve the mechanism through which miR-148a-3p impacts OS, we identified that miR-155-5p overexpression suppressed its target Ripk1 (receptor (TNFRSF)-interacting serine-threonine kinase 1) expression, and miR-155-5p inhibition elevated Ripk1 levels. Ripk1 is directly involved in apoptosis/necroptosis. In OS cells, small interfering RNA against Ripk1 prevented cell death induced by the sequestration of miR-155-5p. Collectively, we show that miR-148a-3p and miR-155-5p are species-conserved deregulated miRNA in OS. Modulation of these miRNAs was specifically toxic to tumor cells but not normal osteoblasts, raising the possibility that these may be tractable targets for miRNA-based therapies for OS.
authors.affiliation: St Vincent's Institute of Medical Research and Department of Medicine, St Vincent's Hospital, University of Melbourne, Fitzroy, Victoria, Australia.
authors.forename: S
authors.initials: S
authors.lastname: Bhattacharya
authors.affiliation: St Vincent's Institute of Medical Research and Department of Medicine, St Vincent's Hospital, University of Melbourne, Fitzroy, Victoria, Australia.
authors.forename: A M
authors.initials: AM
authors.lastname: Chalk
authors.affiliation: St Vincent's Institute of Medical Research and Department of Medicine, St Vincent's Hospital, University of Melbourne, Fitzroy, Victoria, Australia.
authors.forename: A J M
authors.initials: AJ
authors.lastname: Ng
authors.affiliation: St Vincent's Institute of Medical Research and Department of Medicine, St Vincent's Hospital, University of Melbourne, Fitzroy, Victoria, Australia.
authors.forename: T J
authors.initials: TJ
authors.lastname: Martin
authors.affiliation: Myeloma Research Laboratory, School of Medicine, Faculty of Health Sciences, University of Adelaide, Adelaide, South Australia, Australia.|Cancer Theme, South Australian Health and Medical Research Institute, Adelaide, South Australia, Australia.
authors.forename: A C
authors.initials: AC
authors.lastname: Zannettino
authors.affiliation: St Vincent's Institute of Medical Research and Department of Medicine, St Vincent's Hospital, University of Melbourne, Fitzroy, Victoria, Australia.|ACRF Rational Drug Discovery Centre, St Vincent's Institute of Medical Research, Fitzroy, Victoria, Australia.
authors.forename: L E
authors.initials: LE
authors.lastname: Purton
authors.affiliation: Department of Genetics and Yale Stem Cell Center, Yale University, New Haven, CT, USA.
authors.forename: J
authors.initials: J
authors.lastname: Lu
authors.affiliation: St Vincent's Institute of Medical Research and Department of Medicine, St Vincent's Hospital, University of Melbourne, Fitzroy, Victoria, Australia.
authors.forename: E K
authors.initials: EK
authors.lastname: Baker
authors.affiliation: St Vincent's Institute of Medical Research and Department of Medicine, St Vincent's Hospital, University of Melbourne, Fitzroy, Victoria, Australia.|ACRF Rational Drug Discovery Centre, St Vincent's Institute of Medical Research, Fitzroy, Victoria, Australia.
authors.forename: C R
authors.initials: CR
authors.lastname: Walkley
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000235:genetics; D002454:Cell Differentiation / Q000235:genetics; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000235:genetics; D004195:Disease Models, Animal; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D051379:Mice; D035683:MicroRNAs / Q000096:biosynthesis* / Q000235:genetics; D012516:Osteosarcoma / Q000235:genetics* / Q000473:pathology; D053422:Receptor-Interacting Protein Serine-Threonine Kinases / Q000235:genetics*
chemical_list: C550570:MIRN148 microRNA, human; C524942:MIRN155 microRNA, human; D035683:MicroRNAs; C506249:RIPK1 protein, human; D053422:Receptor-Interacting Protein Serine-Threonine Kinases