[肾透明细胞癌中微小RNA miR-129-2和miR-9-1基因的甲基化、其表达变化及其潜在靶基因的激活]

[Methylation of the genes for the microRNAs miR-129-2 and miR-9-1, changes in their expression, and activation of their potential target genes in clear cell renal cell carcinoma].

作者信息

Pronina I V, Klimov E A, Burdennyy A M, Beresneva E V, Fridman M V, Ermilova V D, Kazubskaya T P, Karpukhin A V, Braga E A, Loginov V I

机构信息

Research Centre of Medical Genetics, Moscow, 115478 Russia.

Institute of General Pathology and Pathophysiology, Moscow, 125315 Russia.

出版信息

Mol Biol (Mosk). 2017 Jan-Feb;51(1):73-84. doi: 10.7868/S0026898416060161.

DOI:10.7868/S0026898416060161

PMID:28251969

Abstract

Methylation of promoter CpG islands and microRNA (miRNA) interactions with mRNAs of target genes are epigenetic mechanisms that play a crucial role in deregulation of gene expression and signaling pathways in tumors. Altered expression of six chromosome 3p genes (RARB(2), SEMA3B, RHOA, GPX1, NKIRAS1, and CHL1) and two miRNA genes (MIR-129-2 and MIR-9-1) was observed in primary clear cell renal cell carcinomas (ccRCCs, 31-48 samples) by RT-PCR and qPCR. Significant downregulation (p < 0.05, Fisher's exact test) was observed for SEMA3B, NKIRAS1, and CHL1; and differential expression, for the other chromosome 3p and miRNA genes. Methylation-specific PCR with primers to RARB(2), SEMA3B, MIR-129-2, and MIR-9-1 showed that their methylation frequency was significantly (p < 0.05, Fisher's exact test) elevated in the ccRCC samples. Significant correlations between promoter methylation and expression were confirmed for SEMA3B and observed for the first time for RARB(2), GPX1, and MIR-129-2 in ccRCC (Spearman's correlation coefficient rs ranging 0.31-0.60, p < 0.05). The MIR-129-2 and RARB(2) methylation frequencies significantly correlated with ccRCC progression. MIR-129-2 methylation correlated with upregulation of RARB(2), RHOA, NKIRAS1, and CHL1 (rs ranging 0.35-0.53, p < 0.05). The findings implicate methylation in regulating RARB(2), SEMA3B, GPX1, and MIR-129-2 and indicate that miR-129-2 and methylation of its gene affect RARB(2), RHOA, NKIRAS1, and CHL1 expression.

摘要

启动子CpG岛甲基化以及微小RNA（miRNA）与靶基因mRNA的相互作用是表观遗传机制，在肿瘤中基因表达失调和信号通路中起着关键作用。通过逆转录聚合酶链反应（RT-PCR）和定量聚合酶链反应（qPCR），在原发性透明细胞肾细胞癌（ccRCC，31 - 48个样本）中观察到6个3号染色体p臂基因（RARB(2)、SEMA3B、RHOA、GPX1、NKIRAS1和CHL1）以及2个miRNA基因（MIR-129-2和MIR-9-1）的表达改变。观察到SEMA3B、NKIRAS1和CHL1有显著下调（p < 0.05，Fisher精确检验）；而其他3号染色体p臂和miRNA基因有差异表达。使用针对RARB(2)、SEMA3B、MIR-129-2和MIR-9-1的引物进行甲基化特异性PCR显示，它们在ccRCC样本中的甲基化频率显著升高（p < 0.05，Fisher精确检验）。在ccRCC中证实了SEMA3B启动子甲基化与表达之间存在显著相关性，并且首次观察到RARB(2)、GPX1和MIR-129-2存在这种相关性（Spearman相关系数rs范围为0.31 - 0.60，p < 0.05）。MIR-129-2和RARB(2)的甲基化频率与ccRCC进展显著相关。MIR-129-2甲基化与RARB(2)、RHOA、NKIRAS1和CHL1的上调相关（rs范围为0.35 - 0.53，p < 0.05）。这些发现表明甲基化参与调控RARB(2)、SEMA3B、GPX1和MIR-129-2，并表明miR-129-2及其基因的甲基化影响RARB(2)、RHOA、NKIRAS1和CHL1的表达。