Project description:Distinct processes govern the transition from myometrial quiescence to activation during both term and preterm labor. We sought the specific gene sets responsible for initiating term and preterm labor, along with a core set of effector genes necessary for labor independent of gestational age and the underlying trigger. The Effector Gene Set consisted of 49 genes present in both preterm and term labor but absent from non-labor samples. 122 genes were specific to preterm labor (Preterm Initiator Set) and 229 to term labor (Term Initiator Set). The Term Initiator and the Effector Sets reflected predominantly inflammatory processes. Surprisingly, the Preterm Initiator Gene Set reflected molecular and biological events almost exclusive of inflammation. Preterm and term labor differ dramatically in their unique, initiator gene profiles, suggesting alternative pathways underlie these events. Inflammatory processes are ubiquitous to the Term Initiator and the Effector Gene Sets, supporting the idea term parturition is an inflammatory process. The absence of inflammatory processes in the Preterm Initiator Set suggests inflammation is secondary to processes triggering spontaneous preterm birth, and could explain the lack of therapeutic efficacy associated with anti inflammatory/antibiotic regimens. Experiment Overall Design: Myometrial gene expression was analyzed from samples obtained at term (n=6) or preterm (n=6) with and without labor using cDNA microarrays. Patients in preterm labor all had intra amniotic inflammation. Gene sets were generated using logical operations within a functional mapping tool (MetaCoreâ¢, GeneGo, St. Joseph, MI). Relevant gene sets were validated with quantitative real-time polymerase chain reaction.
Project description:This study evaluates the gene expression patterns in 36 decidual samples of women having gone through different types of child birth. The samples were profiled on Illumina Human HT-12_v4 BeadArrays. The analysis includes quality control and exploratory analysis of the dataset, followed by the identification of differentially expressed genes (DEGs) and finally, functional analysis for enrichment of KEGG pathways and GO terms amongst the DEGs. The statistical analysis was performed for six comparisons: Term labour (TL) vs Term not labour (TNL), TL vs Preterm labour (PTL), TL vs Preterm non-labour (PTNL), TNL vs PTL, TNL vs PTNL and PTL vs PTNL. This study evaluates the gene expression levels from decidual samples obtained from women giving birth with different types of labour. The dataset was composed of 36 Illumina Human HT-12_v4 expression BeadArrays.
Project description:Distinct processes govern the transition from myometrial quiescence to activation during both term and preterm labor. We sought the specific gene sets responsible for initiating term and preterm labor, along with a core set of effector genes necessary for labor independent of gestational age and the underlying trigger. The Effector Gene Set consisted of 49 genes present in both preterm and term labor but absent from non-labor samples. 122 genes were specific to preterm labor (Preterm Initiator Set) and 229 to term labor (Term Initiator Set). The Term Initiator and the Effector Sets reflected predominantly inflammatory processes. Surprisingly, the Preterm Initiator Gene Set reflected molecular and biological events almost exclusive of inflammation. Preterm and term labor differ dramatically in their unique, initiator gene profiles, suggesting alternative pathways underlie these events. Inflammatory processes are ubiquitous to the Term Initiator and the Effector Gene Sets, supporting the idea term parturition is an inflammatory process. The absence of inflammatory processes in the Preterm Initiator Set suggests inflammation is secondary to processes triggering spontaneous preterm birth, and could explain the lack of therapeutic efficacy associated with anti inflammatory/antibiotic regimens. Keywords: myometrial gene expression, preterm versus term labor
Project description:Microarray analysis to globally assess gene expression at the maternal-fetal interface Experiment Overall Design: 27 non-labored normal preterm and 9 non-labored normal term basal plate samples were analyzed on Affymetrix U133 chips using established protocols. The gene expression profile of preterm was compared to term.
Project description:We hypothesized that preterm spontaneous labor involves aberrant changes in mRNA expression in the placenta. To test this hypothesis, we interrogated the mRNA levels of >50,000 genes and transcript variants using gene expression microarray (Human Genome U133 Plus 2.0 Array, Affymetrix) on 5 placentas collected from preterm spontaneous delivery (<34 weeks of gestation) and another 5 placentas collected from term spontaneous delivery (38-39 weeks). We have identified 229 and 162 genes that were up- or down-regulated, respectively, for more than 3-fold in the preterm placentas compared to the term placentas (Mann-Whitney Rank Sum Test, with multiple testing correction by the Benjamini-Hochberg method, adjusted p-value <= 0.05). Placentas collected from (i) preterm spontaneous delivery (<34 weeks of gestation) and (ii) term spontaneous delivery (38-39 weeks of gestation) were subjected to RNA extraction and hybridization on Affymetrix microarrays. To identify gene expression patterns that are commonly involved in preterm spontaneous labour, we analyzed 5 placentas from each of these 2 groups and tested for any differentially expressed genes by Mann-Whitney Rank Sum Test.
Project description:Genome wide placental DNA methylation profiling of full term and preterm deliveries sampled from 5 full term deliveries and 4 preterm deliveries. The Illumina HumanMethylation450 Beadchip was used to obtain DNA methylation profiles across approximately 485,577 CpGs in formalin fixed samples. Samples included 4 placental tissues from 4 women with preterm delivery and 5 placental tissues from 5 women with full term delivery.
Project description:Genome wide DNA methylation differences in umbilical cord blood (UCB) of preterm and term born neonates. The Illumina 450K Human DNA methylation Beadchip was used to obtain the DNA methylation profiles of 12 preterm and 12 term UCB samples across 450,000 CpGs. 2 samples were removed due to failed quality control, and BMIQ normalization was done with 11 preterm and 11 term samples.
Project description:Genome wide placental DNA methylation profiling of full term and preterm deliveries sampled from 5 full term deliveries and 4 preterm deliveries. The Illumina HumanMethylation450 Beadchip was used to obtain DNA methylation profiles across approximately 485,577 CpGs in formalin fixed samples. Samples included 4 placental tissues from 4 women with preterm delivery and 5 placental tissues from 5 women with full term delivery. 9 women's placental DNA (4 women had perterm deliveries and 5 women had full term deliveries) were hybridised to the Illumina HumanMethylation450 Beadchip
Project description:Preterm birth is multifactorial in origin with several distinct clinical phenotypes of differing etiologies, including idiopathic preterm birth. Preterm birth involves the interaction of genetic, societal and environmental factors such as nutrition, lifestyle and stress that may modulate the length of gestation via the epigenome. DNA methylation is a well-studied epigenetic modification whereby promoter methylation commonly represses gene expression and vice versa. Myometrial tissue was obtained at cesarean section at term with or without labor, preterm without labor, idiopathic preterm labor, and twin gestations with labor. Differences in the myometrial epigenomes were identified at gene promoters, CpG islands, CpG island shores and shelves, gene bodies across the genome between the groups of women with preterm labor of different phenotypes vs. normal term labor. Functional clustering analysis indicated the significantly enriched pathways of hypomethylated genes (permissive) were related to acute inflammatory and acute-phase responses. By contrast, genes that are hypermethylated (repressive) revealed enrichment for contractile fibers and cell. This study provides the first high-resolution DNA methylome of human myometrium with evidence for differences in the methylome that may relate to idiopathic preterm birth via regulation of gene expression. The findings extend previous observations that idiopathic preterm labor is associated with subclinical intrauterine infection and inflammatory pathways and point to targets for further molecular characterization of preterm delivery. Comparison of the human myometrial epigenomes in pregnancies with preterm labor of different phenotypes vs. normal term labor
Project description:Preterm birth is a main determinant of neonatal mortality and morbidity and a major contributor to the overall mortality and burden of disease. However, precise phenotyping of the preterm birth is hampered by the imprecise definition of the clinical phenotype and complexity of the molecular phenotype due to multiple pregnancy tissue types and molecular processes that may contribute to the preterm birth. The studyâ??s aim was to comprehensively evaluate the mRNA transcriptome that characterizes preterm and term labor using precisely phenotyped samples. Expression profiles of 73 genes and non-coding RNA sequences uniquely identified the four groups of patients: delivering preterm with (PL) and without labor (PNL), term with (TL) and without labor (TNL). The largest differences in gene expression among the four groups occurred in decidua, chorion and amnion. The gene expression profiles showed suppression of chemokines expression in TNL, withdrawal of this suppression in TL, activation of multiple pathways of inflammation in PL, and an immune rejection profile in PNL. The genes constituting expression signatures showed over-representation of three putative regulatory elements in their 5â?? and 3â??UTR regions. The results suggest that pregnancy is maintained by downregulation of chemokines at the maternal-fetal interface. Withdrawal of this downregulation results in the term birth and its overriding by the activation of multiple pathways of the immune system in the preterm birth. Complications of the pregnancy associated with impairment of placental function, which necessitated premature delivery of the fetus in the absence of labor, show gene expression patterns associated with immune rejection. 183 total RNA samples from 8 tissue types collected from 35 women grouped into six categories of pregnancy outcome. One microarray replicate per sample. Other Contributors: Radek Bukowski, Sam Parry and the NICHD Genomic and Proteomic Network for Preterm Birth Research