Francisco J. Esteban

A GENOMIC DIAGNOSTIC TOOL FOR HUMAN ENDOMETRIAL RECEPTIVITY BASED ON THE TRANSCRIPTOMIC SIGNATURE

OBJECTIVEnTo create a genomic tool composed of a customized microarray and a bioinformatic predictor for endometrial dating and to detect pathologies of endometrial origin. To define the transcriptomic signature of human endometrial receptivity.nnnDESIGNnTwo cohorts of endometrial samples along the menstrual cycle were used: one to select the genes to be included in the customized microarray (endometrial receptivity array [ERA]), and the other to be analyzed by ERA to train the predictor for endometrial dating and to define the transcriptomic signature. A third cohort including pathological endometrial samples was used to train the predictor for pathological classification.nnnSETTINGnHealthy oocyte donors and patients.nnnPATIENT(S)nHealthy fertile women (88) and women with implantation failure (5) or hydrosalpinx (2).nnnINTERVENTION(S)nHuman endometrial biopsies.nnnMAIN OUTCOME MEASURE(S)nThe gene expression of endometrial biopsies.nnnRESULT(S)nThe ERA included 238 selected genes. The transcriptomic signature was defined by 134 genes. The predictor showed a specificity of 0.8857 and sensitivity of 0.99758 for endometrial dating, and a specificity of 0.1571 and a sensitivity of 0.995 for the pathological classification.nnnCONCLUSION(S)nThis diagnostic tool can be used clinically in reproductive medicine and gynecology. The transcriptomic signature is a potential endometrial receptivity biomarkers cluster.

Human Endometrial Side Population Cells Exhibit Genotypic, Phenotypic and Functional Features of Somatic Stem Cells

During reproductive life, the human endometrium undergoes around 480 cycles of growth, breakdown and regeneration should pregnancy not be achieved. This outstanding regenerative capacity is the basis for womens cycling and its dysfunction may be involved in the etiology of pathological disorders. Therefore, the human endometrial tissue must rely on a remarkable endometrial somatic stem cells (SSC) population. Here we explore the hypothesis that human endometrial side population (SP) cells correspond to somatic stem cells. We isolated, identified and characterized the SP corresponding to the stromal and epithelial compartments using endometrial SP genes signature, immunophenotyping and characteristic telomerase pattern. We analyzed the clonogenic activity of SP cells under hypoxic conditions and the differentiation capacity in vitro to adipogenic and osteogenic lineages. Finally, we demonstrated the functional capability of endometrial SP to develop human endometrium after subcutaneous injection in NOD-SCID mice. Briefly, SP cells of human endometrium from epithelial and stromal compartments display genotypic, phenotypic and functional features of SSC.

Transcriptomic Signature of Trophoblast Differentiation in a Human Embryonic Stem Cell Model

Identification of genes involved in trophoblast differentiation is of great interest in understanding cellular and molecular mechanisms involved in placental development and is relevant clinically to fetal development, fertility, and maternal health. Herein, we investigated differentiation of human embryonic stem cells (hESCs) down the trophoblast lineage by culture with bone morphogenetic protein 4 (BMP4) over a 10-day period. Within 2 days, the stemness markers POU5F1 and NANOG were markedly down-regulated, followed temporally by up-regulation of the CDX2, KRT7, HLA-G, ID2, CGA, and CGB trophoblast markers. To understand, on a global scale, changes in the transcriptome during the differentiation of hESCs down the trophoblast lineage, a large-scale microarray analysis was performed. Through whole-genome analysis, more than 3800 genes displayed statistically significant and 2-fold or greater changes in expression during the time course. Of those genes that showed the largest increases, many were involved in processes associated with trophoblast biology; however, novel genes were also identified. Some of them are hypothesized to be associated mainly with extracellular matrix remodeling (e.g., NID2) and cell migration and invasion (e.g., RAB25). Using Ingenuity pathways analysis software to identify signaling pathways involved in trophoblast differentiation or function, we discovered that many genes are involved in WNT/beta-catenin, ERK/MAPK, NFKB, and calcium signaling pathways, suggesting potential roles for these families in trophoblast development. This work provides an in vitro functional genomic model with which to identify genes involved in trophoblast development.

MicroRNA profiling during mouse ventricular maturation: a role for miR-27 modulating Mef2c expression

AIMSnnon-coding RNA has been recently demonstrated to be a novel mechanism for modulation of gene expression at the post-transcriptional level. The importance of microRNAs in the cardiovascular system is now apparent. Mutations of distinct microRNAs have provided evidence for fundamental roles of microRNAs during cardiovascular development. However, there is limited information about global microRNA profiles during mouse heart development. In this study, we have gained insight from the expression profiles of microRNAs during mouse ventricular development by microarray and qRT-PCR analysis.nnnMETHODS AND RESULTSnour microarray analysis reveals that relatively few microRNAs display either increasing or decreasing expression profiles during ventricular chamber formation. Interestingly, most of the differentially expressed microRNAs display a rather discrete peak of expression at particular developmental stages. Furthermore, we demonstrate that microRNA-27b (miR-27b) displays an overt myocardial expression during heart development and that the transcription factor-encoding gene Mef2c is an miR-27b target.nnnCONCLUSIONnour data present a comprehensive profile of microRNA expression during ventricular maturation, providing an entry point for investigation of the functional roles of the most abundantly and differentially expressed microRNAs during cardiogenesis.

The Protein Kinase A Pathway-Regulated Transcriptome of Endometrial Stromal Fibroblasts Reveals Compromised Differentiation and Persistent Proliferative Potential in Endometriosis

Intrinsic abnormalities in transplanted eutopic endometrium are believed to contribute to the pathogenesis of pelvic endometriosis. Herein we investigated transcriptomic differences in human endometrial stromal fibroblasts (hESFs) from women with (hESF(endo)) vs. without (hESF(nonendo)) endometriosis, in response to activation of the protein kinase A (PKA) pathway with 8-bromoadenosine-cAMP (8-Br-cAMP). hESF(nonendo) (n = 4) and hESF(endo) (n = 4) were isolated from eutopic endometrium and treated +/- 0.5 mm 8-Br-cAMP for 96 h. Purified total RNA was subjected to microarray analysis using the whole-genome Gene 1.0 ST Affymetrix platform. A total of 691 genes were regulated in cAMP-treated hESF(nonendo) vs. 158 genes in hESF(endo), suggesting a blunted response to cAMP/PKA pathway activation in women with disease. Real-time PCR and ELISA validated the decreased expression of decidualization markers in hESF(endo) compared with hESF(nonendo). In the absence of disease, 8-Br-cAMP down-regulated progression through the cell cycle via a decrease in cyclin D1, cyclin-dependent kinase 6, and cell division cycle 2 and an increase in cyclin-dependent kinase inhibitor 1A. However, cell cycle components in hESF(endo) were not responsive to 8-Br-cAMP, resulting in persistence of a proliferative phenotype. hESF(endo) treated with 8-Br-cAMP exhibited altered expression of immune response, extracellular matrix, cytoskeleton, and apoptosis genes. Changes in phosphodiesterase expression and activity were not different among experimental groups. These data support that eutopic hESF(endo) with increased proliferative potential can seed the pelvic cavity via retrograde menstruation and promote establishment, survival, and proliferation of endometriosis lesions, independent of hydrolysis of cAMP and likely due to an inherent abnormality in the PKA pathway.

Unique Transcriptome, Pathways, and Networks in the Human Endometrial Fibroblast Response to Progesterone in Endometriosis

Eutopic endometrium in endometriosis has molecular evidence of resistance to progesterone (P4) and activation of the PKA pathway in the stromal compartment. To investigate global and temporal responses of eutopic endometrium to P4, we compared early (6-h), intermediate (48-h), and late (14-Day) transcriptomes, signaling pathways, and networks of human endometrial stromal fibroblasts (hESF) from women with endometriosis (hESFendo) with hESF from women without endometriosis (hESFnonendo). Endometrial biopsy samples were obtained from subjects with and without mild peritoneal endometriosis (n = 4 per group), and hESF were isolated and treated with P4 (1 μM) plus estradiol (E2) (10 nM), E2 alone (10 nM), or vehicle for up to 14 days. Total RNA was subjected to microarray analysis using a Gene 1.0 ST (Affymetrix) platform and analyzed by using bioinformatic algorithms, and data were validated by quantitative real-time PCR and ELISA. Results revealed unique kinetic expression of specific genes and unique pathways, distinct biological and molecular processes, and signaling pathways and networks during the early, intermediate, and late responses to P4 in both hESFnonendo and hESFendo, although a blunted response to P4 was observed in the latter. The normal response of hESF to P4 involves a tightly regulated kinetic cascade involving key components in the P4 receptor and MAPK signaling pathways that results in inhibition of E2-mediated proliferation and eventual differentiation to the decidual phenotype, but this was not established in the hESFendo early response to P4. The abnormal response of this cell type to P4 may contribute to compromised embryonic implantation and infertility in women with endometriosis.

Fractal-dimension analysis detects cerebral changes in preterm infants with and without intrauterine growth restriction

In the search for a useful parameter to detect and quantify subtle brain abnormalities in infants with intrauterine growth restriction (IUGR), we hypothesised that the analysis of the structural complexity of grey matter (GM) and white matter (WM) using the fractal dimension (FD), a measurement of the topological complexity of an object, could be established as a useful tool for quantitative studies of infant brain morphology. We studied a sample of 18 singleton IUGR premature infants, (12.72 months corrected age (CA), range: 12 months-14 months), 15 preterm infants matched one-to-one for gestational age (GA) at delivery (12.6 months; range: 12 months-14 months), and 15 neonates born at term (12.4 months; range: 11 months-14 months). The neurodevelopmental outcome was assessed in all subjects at 18 months CA according to the Bayley Scale for Infant and Toddler Development - Third edition (BSID-III). For MRI acquisition and processing, the infants were scanned at 12 months CA, in a TIM TRIO 3T scanner, sleeping naturally. Images were pre-processed using the SPM5 toolbox, the GM and WM segmented under the VBM5 toolbox, and the box-counting method was applied for FD calculation of normal and skeletonized segmented images. The results showed a significant decrease of the FD of the brain GM and WM in the IUGR group when compared to the preterm or at-term controls. We also identified a significant linear tendency of both GM and WM FD from IUGR to preterm and term groups. Finally, multiple linear analyses between the FD of the GM or WM and the neurodevelopmental scales showed a significant regression of the language and motor scales with the FD of the GM. In conclusion, a decreased FD of the GM and WM in IUGR infants could be a sensitive indicator for the investigation of structural brain abnormalities in the IUGR population at 12 months of age, which can also be related to functional disorders.

Embryologic outcome and secretome profile of implanted blastocysts obtained after coculture in human endometrial epithelial cells versus the sequential system.

OBJECTIVEnTo compare embryologic and clinical outcomes in terms of preimplantation development, implantation, pregnancy rates, and secretome profile of implanted blastocysts from the preimplantation genetic diagnosis program grown in sequential versus endometrial epithelial cell (EEC) coculture system.nnnDESIGNnRetrospective clinical study and prospective experimental study.nnnSETTINGnIn vitro fertilization clinical unit and university research laboratory.nnnINTERVENTION(S)nBlastomere biopsy, embryo culture, blastocyst transfer, and protein analysis of the media conditioned from implanted embryos obtained from coculture and sequential systems.nnnMAIN OUTCOME MEASURE(S)nClinical study: blastocyst, implantation, and gestation rates in own and donated oocytes. Experimental study: differential protein analysis of implanted embryos grown in coculture system versus sequential system.nnnRESULT(S)nOf the 12,377 embryos analyzed, the blastocyst rates were 56.0% versus 45.9% in the coculture versus the sequential system, respectively, with own oocytes. With ovum donation, the rates were 70.5% versus 56.4%, respectively. Reproductive outcomes in terms of pregnancy rates (39.1% vs. 27.5%) and implantation rates (33.3% vs. 20.9%,) were statistically higher in EEC coculture versus sequential media. Furthermore, the protein profile of the EEC coculture versus the sequential system was obtained. Interleukin-6 (IL-6) was the most secreted protein by the EEC culture. Further ELISA experiments showed that the IL-6 present in the sequential medium diminished in implanted blastocysts.nnnCONCLUSION(S)nThe coculture system favors blastocyst development and implantation rates, given the contribution of the factors secreted by endometrial epithelial cells, such as IL-6.

The Bone Marrow-Derived Human Mesenchymal Stem Cell: Potential Progenitor of the Endometrial Stromal Fibroblast

The cellular sources that contribute to the renewal of human endometrium are largely unknown. It has been suggested that endometrial stem cells originate from bone marrow-derived mesenchymal stem cells (MSC), with subsequent development into endometrial stromal fibroblasts (hESF). We hypothesized that if bone marrow-derived MSC contribute to endometrial regeneration and are progenitors of hESF, their treatment with agents known to regulate hESF differentiation could promote their differentiation down the stromal fibroblast lineage. To this end, we treated bone marrow-derived MSC with estradiol and progesterone, bone morphogenetic protein 2 (BMP2), and activators of the protein kinase A (PKA) pathway and investigated specific markers of hESF differentiation (decidualization). Furthermore, we investigated the transcriptome of these cells in response to cAMP and compared this to the transcriptome of hESF decidualized in response to activation of the PKA pathway. The data support the idea that MSC can be differentiated down the hESF pathway, as evidenced by changes in cell shape and common expression of decidual markers and other genes important in hESF differentiation and function, and that bone marrow-derived MSC may be a source of endometrial stem/progenitor cells. In addition, we identified MSC-specific markers that distinguish them from other fibroblasts and, in particular, from hESF, which is of biologic relevance and practical value to the field of endometrial stem cell research.

Effect of ICSI on gene expression and development of mouse preimplantation embryos

BACKGROUNDnIn vitro culture (IVC) and IVF of preimplantation mouse embryos are associated with changes in gene expression. It is however not known whether ICSI has additional effects on the transcriptome of mouse blastocysts.nnnMETHODSnWe compared gene expression and development of mouse blastocysts produced by ICSI and cultured in Whittens medium (ICSI(WM)) or KSOM medium with amino acids (ICSI(KSOMaa)) with control blastocysts flushed out of the uterus on post coital Day 3.5 (in vivo). In addition, we compared gene expression in embryos generated by IVF or ICSI using WM. Global pattern of gene expression was assessed using the Affymetrix 430 2.0 chip.nnnRESULTSnBlastocysts from ICSI fertilization have a reduction in the number of trophoblastic and inner cell mass cells compared with embryos generated in vivo. Approximately 1000 genes are differentially expressed between ICSI blastocyst and in vivo blastocysts; proliferation, apoptosis and morphogenetic pathways are the most common pathways altered after IVC. Unexpectedly, expression of only 41 genes was significantly different between embryo cultured in suboptimal conditions (WM) or optimal conditions (KSOM(aa)).nnnCONCLUSIONSnOur results suggest that fertilization by ICSI may play a more important role in shaping the transcriptome of the developing mouse embryo than the culture media used.