title: microRNA-10b Is Overexpressed and Critical for Cell Survival and Proliferation in Medulloblastoma.
abstract: This study demonstrates the effects of miRNA-10b on medulloblastoma proliferation through transcriptional induction of the anti-apoptotic protein BCL2. Using a cancer specific miRNA-array, high expression of miRNA-10b in medulloblastoma cell lines compared to a normal cerebellar control was shown, and this was confirmed with real time PCR (RT-PCR). Two medulloblastoma cell lines (DAOY and UW228) were transiently transfected with control miRNA, miRNA-10b inhibitor or miRNA-10b mimic and subjected to RT-PCR, MTT, apoptosis, clonogenic assay and western blot analysis. Transfection of miRNA-10b inhibitor induced a significant down-regulation of miRNA-10b expression, inhibited proliferation, and induced apoptosis, while miRNA-10b mimic exerted an opposite effect. Inhibition of miRNA-10b abrogated the colony-forming capability of medulloblastoma cells, and markedly down-regulated the expression of BCL2. Down-regulation of BCL2 by antisense oligonucleotides or siRNA also significantly down-regulated miRNA-10b, suggesting that BCL2 is a major mediator of the effects of miRNA-10b. ABT-737 and ABT-199, potent inhibitors of BCL2, downregulated the expression of miRNA-10b and increased apoptosis. Analysis of miRNA-10b levels in 13 primary medulloblastoma samples revealed that the 2 patients with the highest levels of miRNA-10b had multiple recurrences (4.5) and died within 8 years of diagnosis, compared with the 11 patients with low levels of miRNA-10b who had a mean of 1.2 recurrences and nearly 40% long-term survival. The data presented here indicate that miRNA-10b may act as an oncomir in medulloblastoma tumorigenesis, and reveal a previously unreported mechanism with Bcl-2 as a mediator of the effects of miRNA-10b upon medulloblastoma cell survival.
authors.affiliation: Department of Neurological Surgery, Children's Hospital of Pittsburgh, University of Pittsburgh Medical School, Pittsburgh, Pennsylvania, United States of America.
authors.forename: Rekha
authors.initials: R
authors.lastname: Pal
authors.affiliation: Department of Neurological Surgery, Children's Hospital of Pittsburgh, University of Pittsburgh Medical School, Pittsburgh, Pennsylvania, United States of America.
authors.forename: Stephanie
authors.initials: S
authors.lastname: Greene
mesh_terms: D000293:Adolescent; D000328:Adult; D001713:Biphenyl Compounds / Q000494:pharmacology; D019086:Bridged Bicyclo Compounds, Heterocyclic / Q000494:pharmacology; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000235:genetics; D002470:Cell Survival / Q000235:genetics; D002528:Cerebellar Neoplasms / Q000175:diagnosis / Q000378:metabolism / Q000473:pathology; D002648:Child; D002675:Child, Preschool; D015536:Down-Regulation / Q000187:drug effects; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007223:Infant; D008297:Male; D008527:Medulloblastoma / Q000175:diagnosis / Q000378:metabolism / Q000473:pathology; D035683:MicroRNAs / Q000037:antagonists & inhibitors / Q000235:genetics* / Q000378:metabolism*; D009364:Neoplasm Recurrence, Local; D009596:Nitrophenols / Q000494:pharmacology; D016376:Oligonucleotides, Antisense / Q000378:metabolism; D010879:Piperazines / Q000494:pharmacology; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000378:metabolism; D013449:Sulfonamides / Q000494:pharmacology
chemical_list: C501332:ABT-737; D001713:Biphenyl Compounds; D019086:Bridged Bicyclo Compounds, Heterocyclic; C547183:MIRN10 microRNA, human; D035683:MicroRNAs; D009596:Nitrophenols; D016376:Oligonucleotides, Antisense; D010879:Piperazines; D019253:Proto-Oncogene Proteins c-bcl-2; D034741:RNA, Small Interfering; D013449:Sulfonamides; C579720:venetoclax