Department of Obstetrics and Gynecology, The Ohio State University College of Medicine, Columbus, Ohio, USA.
Center for Perinatal Research, Nationwide Children's Hospital, Columbus, Ohio, USA.
Biol Reprod. 2018 Jun 1;98(6):834-845. doi: 10.1093/biolre/ioy040.
We conducted integrated transcriptomics network analyses of miRNA and mRNA interactions in human myometrium to identify novel molecular candidates potentially involved in human parturition. Myometrial biopsies were collected from women undergoing primary Cesarean deliveries in well-characterized clinical scenarios: (1) spontaneous term labor (TL, n = 5); (2) term nonlabor (TNL, n = 5); (3) spontaneous preterm birth (PTB) with histologic chorioamnionitis (PTB-HCA, n = 5); and (4) indicated PTB nonlabor (PTB-NL, n = 5). RNAs were profiled using RNA sequencing, and miRNA-target interaction networks were mined for key discriminatory subnetworks. Forty miRNAs differed between TL and TNL myometrium, while seven miRNAs differed between PTB-HCA vs. PTB-NL specimens; six of these were cross-validated using quantitative PCR. Based on the combined sequencing data, unsupervised clustering revealed two nonoverlapping cohorts that differed primarily by absence or presence of uterine quiescence, rather than gestational age or original clinical cohort. The intersection of differentially expressed miRNAs and their targets predicted 22 subnetworks with enriched representation of miR-146b-5p, miR-223-3p, and miR-150-5p among miRNAs, and of myocyte enhancer factor-2C (MEF2C) among mRNAs. Of four known MEF2 transcription factors, decreased MEF2A and MEF2C expression in women with uterine nonquiescence was observed in the sequencing data, and validated in a second cohort by quantitative PCR. Immunohistochemistry localized MEF2A and MEF2C to myometrial smooth muscle cells and confirmed decreased abundance with labor. Collectively, these results suggest altered MEF2 expression may represent a previously unrecognized process through which miRNAs contribute to the phenotypic switch from quiescence to labor in human myometrium.
我们对人类子宫肌层中的 miRNA 和 mRNA 相互作用进行了综合转录组学网络分析，以鉴定可能参与人类分娩的新分子候选物。在明确定义的临床情况下，从接受初次剖宫产的女性中采集子宫肌活检：（1）自发性足月分娩（TL，n=5）；（2）足月非分娩（TNL，n=5）；（3）自发性早产伴组织学绒毛膜羊膜炎（PTB-HCA，n=5）；和（4）有指征的早产非分娩（PTB-NL，n=5）。使用 RNA 测序对 RNA 进行了分析，并对 miRNA 靶标相互作用网络进行了挖掘，以确定关键的区分子网。TL 和 TNL 子宫肌之间有 40 个 miRNA 不同，PTB-HCA 与 PTB-NL 标本之间有 7 个 miRNA 不同；其中 6 个使用定量 PCR 进行了交叉验证。基于组合测序数据，无监督聚类显示两个不重叠的队列，这些队列主要通过子宫静止的存在与否来区分，而不是通过妊娠年龄或原始临床队列来区分。差异表达的 miRNA 及其靶标的交集预测了 22 个具有丰富 miR-146b-5p、miR-223-3p 和 miR-150-5p 表达的子网，以及 mRNAs 中肌细胞增强因子-2C（MEF2C）的表达。在四个已知的 MEF2 转录因子中，在具有子宫非静止性的女性中观察到测序数据中 MEF2A 和 MEF2C 的表达减少，并通过定量 PCR 在第二个队列中得到验证。免疫组织化学将 MEF2A 和 MEF2C 定位到子宫平滑肌细胞，并通过实验确认了与分娩相关的丰度降低。总的来说，这些结果表明，改变的 MEF2 表达可能代表一种以前未被识别的过程，通过该过程，miRNA 有助于人类子宫肌从静止到分娩的表型转变。
