Dataset Information

DNA Methylation Influences miRNA Expression in Gonadotroph Pituitary Tumors.

ABSTRACT: microRNAs are involved in pathogenesis of cancer. DNA methylation plays a role in transcription of miRNA-encoding genes and may contribute to changed miRNA expression in tumors. This issue was not investigated in pituitary neuroendocrine tumors (PitNETs) previously. DNA methylation patterns, assessed with HumanMethylation450K arrays in 34 PitNETs and five normal pituitaries, were used to determine differentially methylated CpGs located at miRNA genes. It showed aberrant methylation in regions encoding for 131 miRNAs. DNA methylation data and matched miRNA expression profiles, determined with next-generation sequencing (NGS) of small RNAs, were correlated in 15 PitNETs. This showed relationship between methylation and expression levels for 12 miRNAs. DNA methylation and expression levels of three of them (MIR145, MIR21, and MIR184) were determined in the independent group of 80 tumors with pyrosequencing and qRT-PCR and results confirmed both aberrant methylation in PitNETs and correlation between methylation and expression. Additionally, in silico target prediction was combined with analysis of established miRNA profiles and matched mRNA expression pattern, assessed with amplicon-based NGS to indicate putative target genes of epigenetically deregulated miRNAs. This study reveals aberrant DNA methylation in miRNA-encoding genes in gonadotroph PitNETs. Methylation changes affect expression level of miRNAs that regulate putative target genes with tumorigenesis-relevant functions.

SUBMITTER: Boresowicz J

PROVIDER: S-EPMC7281098 | biostudies-literature | 2020 May

REPOSITORIES: biostudies-literature

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DNA Methylation Influences miRNA Expression in Gonadotroph Pituitary Tumors.

Boresowicz Joanna J Kober Paulina P Rusetska Natalia N Maksymowicz Maria M Paziewska Agnieszka A Dąbrowska Michalina M Zeber-Lubecka Natalia N Kunicki Jacek J Bonicki Wiesław W Ostrowski Jerzy J Siedlecki Janusz A JA Bujko Mateusz M

Life (Basel, Switzerland) 20200513 5

microRNAs are involved in pathogenesis of cancer. DNA methylation plays a role in transcription of miRNA-encoding genes and may contribute to changed miRNA expression in tumors. This issue was not investigated in pituitary neuroendocrine tumors (PitNETs) previously. DNA methylation patterns, assessed with HumanMethylation450K arrays in 34 PitNETs and five normal pituitaries, were used to determine differentially methylated CpGs located at miRNA genes. It showed aberrant methylation in regions en ...[more]

PMID: 32413978

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Dataset Information

DNA Methylation Influences miRNA Expression in Gonadotroph Pituitary Tumors.

Publications

DNA Methylation Influences miRNA Expression in Gonadotroph Pituitary Tumors.

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