Kim Chi Vo

MicroRNA expression profiling of eutopic secretory endometrium in women with versus without endometriosis.

Endometriosis is a common gynecologic disorder characterized by pain and infertility. In addition to estrogen dependence, progesterone resistance is an emerging feature of this disorder. Specifically, a delayed transition from the proliferative to secretory phase as evidenced by dysregulation of progesterone target genes and maintenance of a proliferative molecular fingerprint in the early secretory endometrium (ESE) has been reported. MicroRNAs (miRNAs) are small noncoding RNAs that collectively represent a novel class of regulators of gene expression. In an effort to investigate further the observed progesterone resistance in the ESE of women with endometriosis, we conducted array-based, global miRNA profiling. We report distinct miRNA expression profiles in the ESE of women with versus without endometriosis in a subset of samples previously used in global gene expression analysis. Specifically, the miR-9 and miR-34 miRNA families evidenced dysregulation. Integration of the miRNA and gene expression profiles provides unique insights into the molecular basis of this enigmatic disorder and, possibly, the regulation of the proliferative phenotype during the early secretory phase of the menstrual cycle in affected women.

Steroidogenic Enzyme and Key Decidualization Marker Dysregulation in Endometrial Stromal Cells from Women with Versus Without Endometriosis

Abstract Identification of mechanisms underlying endometriosis pathogenesis will facilitate understanding and treatment of infertility and pain associated with this disorder. Herein, we investigated the expression of steroidogenic pathway enzymes and key decidualization biomarkers in endometrial tissue and in eutopic endometrial stromal fibroblasts (hESFs) from women with vs. those without endometriosis, and subsequently treated in vitro with 8-bromo-cAMP (8-Br-cAMP) or progesterone (P4). Real-time quantitative PCR, immunohistochemistry, ELISA, and radiometric aromatase activity assay were used. The results demonstrate significantly increased (14.5-fold; P = 0.037) expression of aromatase in eutopic endometrium of women with disease. In 8-Br-cAMP-treated hESF from eutopic endometrium of women with endometriosis, the balance in estradiol (E2) and P4 biosynthetic and metabolizing enzymes is disturbed (decreased HSD3B1 and HSD17B2, and increased HSD17B1 and aromatase), with the equilibrium being shifted towards an E2-enriched milieu. However, hESF from the same group of women treated with P4 did not demonstrate such responsiveness. Lower expression of IGFBP1 and prolactin mRNA and protein was observed in hESF from women with vs. those without endometriosis in response to 8-Br-cAMP, but not P4, suggesting a blunted response of these decidual biomarkers to activation of the PKA pathway in eutopic endometrium in women with disease. The dichotomy of 8-Br-cAMP regulation of select steroidogenic enzymes leading to an enriched E2 milieu within the endometrium and a blunted response of decidual biomarkers to this decidualizing agent of hESF from women with endometriosis suggests resistance to full decidualization of the stromal fibroblasts and mechanisms underlying implantation failure and the pathophysiology of this disorder.

Developmental response to hypoxia

Molecular mechanisms underlying fetal growth restriction due to placental insufficiency and in utero hypoxia are not well understood. In the current study, time‐dependent (3 h–11 days) changes in fetal tissue gene expression in a rat model of in utero hypoxia compared with normoxic controls were investigated as an initial approach to understand molecular events underlying fetal development in response to hypoxia. Under hypoxic conditions, litter size was reduced and IGFBP‐1 was up‐regulated in maternal serum and in fetal liver and heart. Tissue‐specific, distinct regulatory patterns of gene expression were observed under acute vs. chronic hypoxic conditions. Induction of glycolytic enzymes was an early event in response to hypoxia during organ development;consis‐tently, tissue‐specific induction of calcium homeostasis‐related genes and suppression of growth‐related genes were observed, suggesting mechanisms underlying hypoxia‐related fetal growth restriction. Furthermore, induction of inflammation‐related genes in placentas exposed to long‐term hypoxia (11 days) suggests a mechanism for placental dysfunction and impaired pregnancy outcome accompanying in utero hypoxia.— Huang, S.‐T. J., Vo, K. C. T., Lyell, D. J., Faessen, G. H., Tulac, S., Tibshirani, R., Giaccia, A. J., Giudice, L. C. Developmental response to hypoxia. FASEB J. 18, 1348–1365 (2004)

Diversity of the Vaginal Microbiome Correlates With Preterm Birth

Reproductive tract infection is a major initiator of preterm birth (PTB). The objective of this prospective cohort study of 88 participants was to determine whether PTB correlates with the vaginal microbiome during pregnancy. Total DNA was purified from posterior vaginal fornix swabs during gestation. The 16S ribosomal RNA gene was amplified using polymerase chain reaction primers, followed by chain-termination sequencing. Bacteria were identified by comparing contig consensus sequences with the Ribosomal Database Project. Dichotomous responses were summarized via proportions and continuous variables via means ± standard deviation. Mean Shannon Diversity index differed by Welch t test (P = .00016) between caucasians with PTB and term gestation. Species diversity was greatest among African Americans (P = .0045). Change in microbiome/Lactobacillus content and presence of putative novel/noxious bacteria did not correlate with PTB. We conclude that uncultured vaginal bacteria play an important role in PTB and race/ethnicity and sampling location are important determinants of the vaginal microbiome.

The Immune Environment in Human Endometrium during the Window of Implantation

Problem:  Changes in the immune environment in the endometrium are believed to be important for successful implantation and maintenance of pregnancy. We have previously investigated global gene profiling in human endometrium during the window of implantation by oligonucleotide microarray technology, and analysis of these data underscore the regulation of a group of immune‐related genes. The present study was therefore conducted to examine the pattern of expression and regulation of these genes including decay accelerating factor (DAF), indoleamine 2,3 dioxygenase (IDO), interleukin‐15 (IL‐15), IL‐15 receptor alpha subunit (IL‐15Rα), interferon regulatory factor‐1 (IRF‐1), lymphotactin (Lpn), natural killer‐associated transcript 2 (NKAT2) and NKG5 in secretory and proliferative human endometrium.

Coculturing human endometrial epithelial cells and stromal fibroblasts alters cell-specific gene expression and cytokine production

OBJECTIVE To determine the effects of coculturing endometrial epithelial cells (eEC) with paired endometrial stromal fibroblasts (eSF) on cell-specific gene expression and cytokine secretion patterns. DESIGN In vitro study. SETTING University research laboratory. PATIENT(S) Endometrial biopsies were obtained from premenopausal women. INTERVENTION(S) Polarized eEC and subject-paired eSF were cultured for 12.5 hours alone (monoculture) or combined in a two-chamber coculture system without cell-cell contact. Cells and conditioned media were analyzed for global gene expression and cytokine secretion, respectively. Purified, endometrial tissue-derived eEC and eSF isolated by fluorescent activated cell sorting (FACS) were used as noncultured controls. MAIN OUTCOME MEASURE(S) Cell-specific global gene expression profiling and analysis of secreted cytokines in eEC/eSF cocultures and respective monocultures. RESULT(S) Transepithelial resistance, diffusible tracer exclusion, expression of tight junction proteins, and apical/basolateral vectorial secretion confirmed eEC structural and functional polarization. Distinct transcriptomes of eEC and eSF were consistent with their respective lineages and their endometrial origin. Coculture of eEC with eSF resulted in altered cell-specific gene expression and cytokine secretion. CONCLUSION(S) This coculture model provides evidence that interactions between endometrial functionally polarized epithelium and stromal fibroblasts affect cell-specific gene expression and cytokine secretion underscoring their relevance when modeling endometrium in vitro.

Global Transcriptome Abnormalities of the Eutopic Endometrium From Women With Adenomyosis

Objective: Adenomyosis is a clinical disorder defined by the presence of endometrial glands and stroma within the myometrium, the pathogenesis of which is poorly understood. We postulate that dysregulation of genes and pathways in eutopic endometrium may predispose to ectopic implantation. No study, to our knowledge, has examined the global transcriptome of isolated eutopic endometrium from women with clinically significant adenomyosis. Design: Laboratory-based study with full institutional review board approval and consents. Material and Methods: Endometrial sampling was performed on hysterectomy specimens (proliferative phase) from symptomatic women with pathologically confirmed diffuse adenomyosis (n = 3). Controls (n = 5) were normo-ovulatory patients without adenomyosis. All patients were free from leiomyoma, endometriosis, and hormonal exposures. Isolated purified total RNA was subjected to microarray analysis using the Gene 1.0 ST Affymetrix platform. Data were analyzed with GeneSpring and Ingenuity Pathway analysis. Validation of several genes was undertaken by quantitative real-time reverse transcriptase polymerase chain reaction. Results: Comparison of transcriptomes of proliferative endometrium from women with and without adenomyosis revealed 140 upregulated and 884 downregulated genes in samples from women with adenomyosis compared to controls. Highly differentially expressed genes include those involved in regulation of apoptosis, steroid hormone responsiveness, and proteins involved in extracellular matrix remodeling as well as microRNAs of unknown significance. Affected canonical pathways included eukaryotic initiation factor 2 signaling, oxidative phosphorylation, mitochondrial dysfunction, estrogen receptor signaling, and mammalian target of rapamycin signaling. Conclusion: The eutopic endometrium in patients with adenomyosis has fundamental abnormalities that may predispose to invasion and survival beyond the myometrial interface.

Cryopreservation and recovery of human endometrial epithelial cells with high viability, purity, and functional fidelity

OBJECTIVE To develop a protocol for cryopreservation and recovery of human endometrial epithelial cells (eECs) retaining molecular and functional characteristics of endometrial epithelium in vivo. DESIGN In vitro study using human endometrial cells. SETTING University research laboratory. PATIENT(S) Endometrial biopsies were obtained from premenopausal women undergoing benign gynecologic procedures. INTERVENTION(S) Primary eECs were cryopreserved in 1% fetal bovine serum/10% dimethylsulfoxide in Defined Keratinocyte Serum-Free Medium (KSFM). Recovered cells were observed for endometrial stromal fibroblast (eSF) contamination and subsequently evaluated for morphology, gene expression, and functional characteristics of freshly cultured eECs and in vivo endometrial epithelium. MAIN OUTCOME MEASURE(S) Analysis of eEC morphology and the absence of eSF contamination; evaluation of epithelial-specific gene and protein expression; assessment of epithelial polarity. RESULT(S) Endometrial epithelial cells recovered after cryopreservation (n = 5) displayed epithelial morphology and expressed E-cadherin (CDH1), occludin (OCLN), claudin1 (CLDN1), and keratin18 (KRT18). Compared with eSF, recovered eECs displayed increased (P<.05) expression of epithelial-specific genes AREG, CDH1, DEFB4A, MMP7, and WNT7A, while exhibiting low-to-undetectable (P<.05) stromal-specific genes COL6A3, HOXA11, MMP2, PDGFRB, and WNT5A. Recovered eECs secreted levels of cytokines and growth factors similarly to freshly cultured eECs. Recovered eECs could form a polarized monolayer with high transepithelial electrical resistance (TER) and impermeability to small molecules, and expressed apical/basolateral localization of CDH1 and apical localization of OCLN. CONCLUSION(S) We have developed a protocol for cryopreservation of eECs in which recovered cells after thawing demonstrate morphologic, transcriptomic, and functional characteristics of human endometrial epithelium in vivo.