Altered expression of miRNAs and methylation of their promoters are correlated in neuroblastoma.
Neuroblastoma is the most common human extracranial solid tumor during infancy. Involvement of several miRNAs in its pathogenesis has been ascertained. Interestingly, most of their encoding genes reside in hypermethylated genomic regions: thus, their tumor suppressor function is normally disallowed in these tumors. To date, the therapeutic role of the demethylating agent 5'-Aza-2 deoxycytidine (5'-AZA) and its effects on miRNAome modulation in neuroblastoma have not been satisfactorily explored. Starting from a high-throughput expression profiling of 754 miRNAs and based on a proper selection, we focused on miR-29a-3p, miR-34b-3p, miR-181c-5p and miR-517a-3p as candidate miRNAs for our analysis. They resulted downregulated in four neuroblastoma cell lines with respect to normal adrenal gland. MiRNAs 29a-3p and 34b-3p also resulted downregulated in vivo in a murine neuroblastoma progression model. Unlike the amount of methylation of their encoding gene promoters, all these miRNAs were significantly overexpressed following treatment with 5'-AZA. Transfection with candidate miRNAs mimics significantly decreased neuroblastoma cells proliferation rate. A lower expression of miR-181c was significantly associated to a worse overall survival in a public dataset of 498 neuroblastoma samples (http://r2.amc.nl). Our data strongly suggest that CDK6, DNMT3A, DNMT3B are targets of miR-29a-3p, while CCNE2 and E2F3 are targets of miR-34b-3p. Based on all these data, we propose that miR-29a-3p, miR-34b-3p, miR-181c-5p and miR-517a-3p are disallowed tumor suppressor genes in neuroblastoma and suggest them as new therapeutic targets in neuroblastoma.
Dipartimento di Scienze Biomediche e Biotecnologiche, Sezione di Biologia e Genetica G Sichel, Unità di BioMedicina Molecolare, Genomica e dei Sistemi Complessi, Università di Catania, Catania, Italy, EU.
Marco
M
Maugeri
Dipartimento di Scienze Biomediche e Biotecnologiche, Sezione di Biologia e Genetica G Sichel, Unità di BioMedicina Molecolare, Genomica e dei Sistemi Complessi, Università di Catania, Catania, Italy, EU.
Davide
D
Barbagallo
Dipartimento di Scienze Biomediche e Biotecnologiche, Sezione di Biologia e Genetica G Sichel, Unità di BioMedicina Molecolare, Genomica e dei Sistemi Complessi, Università di Catania, Catania, Italy, EU.
Cristina
C
Barbagallo
UOS Epigenetica dei Tumori, IRCCS A.O.U. San Martino-IST, Genova, Italy, EU.|Department of HealthSciences, University of Genova, Genova, Italy, EU.
Barbara
B
Banelli
Dipartimento di Biomedicina Clinica e Molecolare, Università di Catania, Ospedale Garibaldi, Catania, Italy, EU.
Stefania
S
Di Mauro
Dipartimento di Biomedicina Clinica e Molecolare, Università di Catania, Ospedale Garibaldi, Catania, Italy, EU.
Francesco
F
Purrello
Dipartimento di Scienze Mediche, Chirurgiche e Tecnologie Avanzate G.F. Ingrassia, Università di Catania, Catania, Italy, EU.
Gaetano
G
Magro
Dipartimento di Scienze Biomediche e Biotecnologiche, Sezione di Biologia e Genetica G Sichel, Unità di BioMedicina Molecolare, Genomica e dei Sistemi Complessi, Università di Catania, Catania, Italy, EU.
Marco
M
Ragusa
Dipartimento di Scienze Biomediche e Biotecnologiche, Sezione di Biologia e Genetica G Sichel, Unità di BioMedicina Molecolare, Genomica e dei Sistemi Complessi, Università di Catania, Catania, Italy, EU.
Cinzia
C
Di Pietro
UOS Epigenetica dei Tumori, IRCCS A.O.U. San Martino-IST, Genova, Italy, EU.
Massimo
M
Romani
Dipartimento di Scienze Biomediche e Biotecnologiche, Sezione di Biologia e Genetica G Sichel, Unità di BioMedicina Molecolare, Genomica e dei Sistemi Complessi, Università di Catania, Catania, Italy, EU.
Michele
M
Purrello
D000818:Animals; D001374:Azacitidine / Q000031:analogs & derivatives / Q000494:pharmacology; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D019295:Computational Biology; D018899:CpG Islands; D019175:DNA Methylation / Q000187:drug effects; D015254:DNA Modification Methylases / Q000037:antagonists & inhibitors / Q000378:metabolism; D030541:Databases, Genetic; D000077209:Decitabine; D004791:Enzyme Inhibitors / Q000494:pharmacology; D044127:Epigenesis, Genetic / Q000187:drug effects; D020869:Gene Expression Profiling / Q000379:methods; D015972:Gene Expression Regulation, Neoplastic; D053263:Gene Regulatory Networks; D020022:Genetic Predisposition to Disease; D059014:High-Throughput Nucleotide Sequencing; D006801:Humans; D053208:Kaplan-Meier Estimate; D051379:Mice; D035683:MicroRNAs / Q000235:genetics* / Q000378:metabolism; D009447:Neuroblastoma / Q000235:genetics* / Q000378:metabolism / Q000401:mortality / Q000628:therapy; D010641:Phenotype; D011379:Prognosis; D011401:Promoter Regions, Genetic; D060066:Protein Interaction Maps; D015398:Signal Transduction; D013997:Time Factors
D004791:Enzyme Inhibitors; D035683:MicroRNAs; D000077209:Decitabine; D015254:DNA Modification Methylases; D001374:Azacitidine
5’-AZA; gene expression; miRNAs encoding genes; neuroblastoma; promoter methylation profiles