title: MiR-30a-5p connects EWS-FLI1 and CD99, two major therapeutic targets in Ewing tumor.
abstract: Ewing sarcoma is a pediatric bone tumor characterized in 85% of cases by the fusion between EWS and FLI1 genes that results in the expression of the EWS-FLI1 aberrant transcription factor. Histologically, the Ewing tumor expresses high levels of the CD99 membrane glycoprotein. It has been recently described that CD99 expression contributes to the Ewing tumor oncogenesis by modulating growth and differentiation of tumor cells. Different studies have also shown that overexpression of EWS-FLI1 induces CD99 expression in non-Ewing cells. At the opposite, the knockdown of EWS-FLI1 expression by siRNA approaches has no significant effect on CD99 mRNA level in Ewing cells. Here, by in vivo and in vitro studies, we show that while EWS-FLI1 inhibition has only slight effects on the amount of CD99 transcript, it induces a dramatic decrease of the CD99 protein expression level, hence suggesting post-transcriptional regulations, possibly mediated by microRNAs. To further investigate this issue, we identified a set of 91 miRNAs that demonstrate EWS-FLI1 modulation, three of them being predicted to bind CD99 3' untranslated region (30'UTR). Among these, we show that miR-30a-5p has the ability to interact with the 30'UTR region of CD99 and to regulate its expression. Moreover, the re-expression of miRNA-30a-5p in Ewing cell line induces decreased cell proliferation and invasion. In this study, we therefore show that miR-30a-5p constitutes a major functional link between EWS-FLI1 and CD99, two critical biomarkers and therapeutic targets in Ewing sarcoma.
authors.affiliation: INSERM U830, Génétique et Biologie des cancers, Institut Curie, Centre de recherche, Paris, France.
authors.forename: G-A
authors.initials: GA
authors.lastname: Franzetti
authors.forename: K
authors.initials: K
authors.lastname: Laud-Duval
authors.forename: D
authors.initials: D
authors.lastname: Bellanger
authors.forename: M-H
authors.initials: MH
authors.lastname: Stern
authors.forename: X
authors.initials: X
authors.lastname: Sastre-Garau
authors.forename: O
authors.initials: O
authors.lastname: Delattre
mesh_terms: D000071443:12E7 Antigen; D000818:Animals; D015703:Antigens, CD / Q000235:genetics* / Q000378:metabolism; D015153:Blotting, Western; D001859:Bone Neoplasms / Q000235:genetics* / Q000378:metabolism; D015815:Cell Adhesion Molecules / Q000235:genetics* / Q000378:metabolism; D045744:Cell Line, Tumor; D005434:Flow Cytometry; D005455:Fluorescent Antibody Technique; D015972:Gene Expression Regulation, Neoplastic / Q000235:genetics*; D006801:Humans; D007150:Immunohistochemistry; D051379:Mice; D016513:Mice, SCID; D035683:MicroRNAs / Q000235:genetics* / Q000378:metabolism; D020411:Oligonucleotide Array Sequence Analysis; D015514:Oncogene Proteins, Fusion / Q000235:genetics* / Q000378:metabolism; D051789:Proto-Oncogene Protein c-fli-1 / Q000235:genetics* / Q000378:metabolism; D034802:RNA-Binding Protein EWS / Q000235:genetics* / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012512:Sarcoma, Ewing / Q000235:genetics* / Q000378:metabolism; D014183:Transplantation, Heterologous
chemical_list: D000071443:12E7 Antigen; D015703:Antigens, CD; C061828:CD99 protein, human; D015815:Cell Adhesion Molecules; C106031:EWS-FLI fusion protein; C546086:MIRN30b microRNA, human; D035683:MicroRNAs; D015514:Oncogene Proteins, Fusion; D051789:Proto-Oncogene Protein c-fli-1; D034802:RNA-Binding Protein EWS