Endomeetriumi ja endometrioosikollete molekulaarse profiili iseloomustamine

Väitekirja elektrooniline versioon ei sisalda publikatsioone.Endometrioos on tõsine günekoloogiline haigus, mida iseloomustab emaka limaskesta ehk endomeetriumi koe kasvamine kolletena väljaspool emakaõõnt. Vaatamata intensiivsetele uuringutele on siiani ebaselge, miks endometrioosikolded moodustavad ja millised on need molekulaarsed muutused, mis haiguse kujunemisele kaasa aitavad. Endometrioosi tekkemehhanismide väljaselgitamist on oluliselt hõlbustanud mikrokiibi- ja sekveneerimistehnoloogiate kiire areng, mis võimaldavad ülevaatlikult kirjeldada molekulaarseid muutuseid endometrioosikolletes ja endomeetriumis. Varasemad suure läbilaskevõimega tehnoloogiatel põhinevad endometrioosi uuringud on paraku jõudnud vastukäivate tulemusteni, mis viitab suure tõenäosusega erinevustele katsete disainis ja seetõttu on väga oluline juba uuringut planeerides pöörata tähelepanu võimalikele kitsaskohtadele. Antud töö eesmärgiks oli leida endometrioosi kujunemist mõjutavaid geneetilisi, epigeneetilisi ja mikroRNAde tasemete muutuseid nii endometrioosikolletes kui ka endomeetriumis, kasutades selleks hoolikalt valitud katseskeemi ja mikrokiipidel ning süvasekveneerimisel põhinevaid tehnoloogiaid. Töö tulemuste põhjal võime järeldada, et kromosomaalsed ümberkorraldused endometrioosikolletes ja endomeetriumis ning muutused endomeetriumi DNA metülatsioonimustris ei ole endometrioosi kujunemise esmasteks põhjusteks. Leidsime viis endometrioosikolletes kõrgelt ekspresseeritud mikroRNAd, mille taseme määramine võimaldab ilma histoloogiliste uuringuteta koldeid tuvastada. See uuring tõi välja ka uuringudisaini olulisuse, näidates et kollete mikroRNA tasemete määramiseks tuleb arvesse võtta kollet ümbritseva koe normaalset mikroRNA profiili. Samuti näitasime, et menstruaaltükli jooksul toimuvad endomeetriumi DNA metülatsioonimustris olulised muutused, mida tuleb haigusseoseliste markerite otsimisel kindlasti arvestada.Endometriosis is a serious gynaecological disease characterized by the growth of functional endometrial tissue outside the uterus. Despite of extensive research it is still unclear why endometriosis develops and what are the molecular events triggering the implantation of endometrial cells into the wrong location. The fast development of microarray and sequencing-based technologies has opened new possibilities to describe molecular changes in endometriotic lesions and endometria of endometriosis patients. However, previous high-throughput studies in endometriosis have provided conflicting results, most probably due to the differences in study design and therefore, it is extremely important to pay attention to possible shortcomings before planning the study. The aim of our study was to find genetic, epigenetic and microRNA markers in endometriotic lesions and endometrial tissue that contribute to the endometriosis development, by using carefully planned study design and high-throughput analysis methods. Based on the results of our study we propose that chromosomal alterations in endometriotic lesions and endometrium and changes in endometrial DNA methylation are not the key events responsible for disease development. In microRNA study, signature of five upregulated microRNAs in endometriotic lesions that enable correct diagnosis of endometriotic lesions without the need for traditional histological evaluation of tissue biopsy, was found. Also, the results of this study accentuated the relevance of study design and indicated that for identification of lesion specific miRNAs the normal miRNA signature of healthy tissue should be considered. Furthermore, we found that normal epigenetic changes occurring in endometrium across the menstrual cycle phases should be considered when looking for disease-specific DNA methylation markers

Otsides nõela heinakuhjast – endometrioosi biomarkerid

Endometrioosi diagnoosimiseks puuduvad siiani mitteinvasiivsed ja minimaalselt invasiivsed biomarkerid ning haiguse diagnoos põhineb peamiselt laparoskoopilisel operatsioonil ja endometrioosikollete histoloogilisel uuringul. Kuigi endometrioosi biomarkereid on vereplasmast ja -seerumist, uriinist, menstruaalverest, emakaõõne aspiraadist ja ka endomeetriumi koest aktiivselt otsitud, on leitud markerite usaldusväärsus endometrioosi diagnoosimisel jäänud siiski tagasihoidlikuks. Ülevaates on tehtud kokkuvõte endometrioosi biomarkerite otsingute hetkeseisust ja leitud markerite kasutatavusest kliinilises praktikas. Eesti Arst 2017; 96(6):335–34

Mehe geneetiline viljatus

Geneetilise põhjusega viljatus diagnoositakse 10–15%-l viljatutest meestest. Sagedasemateks teadaolevateks geneetilisteks põhjusteks on autosoomsete ja sugukromosoomide arvu, struktuuri ja ümberpaiknemise anomaaliad. Lisaks on tuvastatud suur hulk reproduktiivsüsteemiga seotud geene ja neis esinevaid geenivariatsioone, mille roll meeste viljatuse patogeneesis ei ole üheselt selge. Senised meeste viljatuse ja geenivariatsioonide vahelised uuringud on olulisi seoseid leidnud vaid vähestel juhtudel. Siiski on geneetilised uuringud kiiresti ja pidevalt arenev valdkond. Saadud teadmised peaksid tooma kliinilisse meditsiini uusi geneetilisi markereid, mis võimaldaksid senisest edukamalt diagnoosida meeste geneetilist viljatust. Artiklis on antud lühiülevaade meeste viljatuse geneetilistest põhjustest ning tutvustatud mõningaid võimalikke mehe viljakust mõjutavaid geene ning geeni polümorfi sme. Eesti Arst 2008; 87(9):628−63

Differentially-Expressed miRNAs in Ectopic Stromal Cells Contribute to Endometriosis Development : The Plausible Role of miR-139-5p and miR-375

microRNA (miRNA) expression level alterations between endometrial tissue and endometriotic lesions indicate their involvement in endometriosis pathogenesis. However, as both endometrium and endometriotic lesions consist of different cell types in various proportions, it is not clear which cells contribute to variability in miRNA levels and the overall knowledge about cell-type specific miRNA expression in ectopic cells is scarce. Therefore, we utilized fluorescence-activated cell sorting to isolate endometrial stromal cells from paired endometrial and endometrioma biopsies and combined it with high-throughput sequencing to determine miRNA alterations in endometriotic stroma. The analysis revealed 149 abnormally expressed miRNAs in endometriotic lesions, including extensive upregulation of miR-139-5p and downregulation of miR-375 compared to eutopic cells. miRNA transfection experiments in the endometrial stromal cell line ST-T1b showed that the overexpression of miR-139-5p resulted in the downregulation of homeobox A9 (HOXA9) and HOXA10 expression, whereas the endothelin 1 (EDN1) gene was regulated by miR-375. The results of this study provide further insights into the complex molecular mechanisms involved in endometriosis pathogenesis and demonstrate the necessity for cell-type-specific analysis of ectopic tissues to understand the interactions between different cell populations in disease onset and progression.Peer reviewe

High-throughput mRNA sequencing of stromal cells from endometriomas and endometrium

The aetiology of endometriosis is still unclear and to find mechanisms behind the disease development, it is important to study each cell type from endometrium and ectopic lesions independently. The objective of this study was to uncover complete mRNA profiles in uncultured stromal cells from paired samples of endometriomas and eutopic endometrium. High-throughput mRNA sequencing revealed over 1300 dysregulated genes in stromal cells from ectopic lesions, including several novel genes in the context of endometriosis. Functional annotation analysis of differentially expressed genes highlighted pathways related to cell adhesion, extracellular matrix–receptor interaction and complement and coagulation cascade. Most importantly, we found a simultaneous upregulation of complement system components and inhibitors, indicating major imbalances in complement regulation in ectopic stromal cells. We also performed in vitro experiments to evaluate the effect of endometriosis patients’ peritoneal fluid (PF) on complement system gene expression levels, but no significant impact of PF on C3, CD55 and CFH levels was observed. In conclusion, the use of isolated stromal cells enables to determine gene expression levels without the background interference of other cell types. In the future, a new standard design studying all cell types from endometriotic lesions separately should be applied to reveal novel mechanisms behind endometriosis pathogenesis

Endometrioos – anamneesist diagnoosini

Uuringu eesmärk. Töö eesmärgiks oli anda ülevaade aastatel 2005–2008 endometrioosile viitavate kaebustega naistearsti vastuvõtule pöördunud ning diagnostilise laparoskoopia/laparotoomia läbinud patsientide küsitluslehtede andmetest ning leida võimalikke endometrioosiga seotud kaebuseid ja riskitegureid. Metoodika. Retrospektiivne uuring, mille valimi moodustasid TÜ Kliinikumi naistekliinikus laparoskoopia/laparotoomia läbinud 170 naist, kellest 118-l (69,4%) diagnoositi endometrioos ja 52-l (30,6%) haigust ei tuvastatud. Patsiendid, kellel operatsiooni käigus endometrioosi ei tuvastatud, moodustasid edasistes analüüsides kontrollrühma. Tulemused ja järeldused. Uuringus osalenud endometrioosi ja kontrollrühma naiste üld- ja reproduktiivanamneesis olulisi erinevusi ei leitud, kuid endometrioosiga patsiendid kaebasid mõnevõrra sagedamini kogu menstruatsiooni kestel esinevaid alakõhuvalusid ning menstruatsiooniaegset valulikkust või veritsust defekatsioonil. Kontrollrühma naised olid sagedamini suitsetajad (32,7% vs 17,8%, p = 0,02) ning olid rohkem põdenud sugulisel teel levivaid haigusi (48,1% vs 25,4%, p = 0,01). Võrreldes endometrioosi mõõduka-raske vormiga esines minimaalse-kerge vormi korral sagedamini viljatust (vastavalt 34,7% ja 76,8%; p vs 27,5%; p = 0,02). Kokkuvõttes leidsime, et kogutud anamneesi ja kaebuste alusel on raske ennustada endometrioosi esinemist ja raskusastet. Diagnoos kinnitatakse vaid laparoskoopilise ja histoloogilise leiu põhjal. Endometrioosi kergemad vormid on aga seotud naise reproduktiivfunktsiooni häiretega – viljatuse ja spontaanabortidega. Eesti Arst 2011; 90(7):321–32

Aberrant expression of genes associated with stemness and cancer in endometria and endometrioma in a subset of women with endometriosis

STUDY QUESTION Is there molecular evidence for a link between endometriosis and endometriosis-associated ovarian cancers (EAOC)? STUDY ANSWER We identified aberrant gene expression signatures associated with malignant transformation in a small subgroup of women with ovarian endometriosis. WHAT IS KNOWN ALREADY Epidemiological studies have shown an increased risk of EAOC in women with ovarian endometriosis. However, the cellular and molecular changes leading to EAOC are largely unexplored. STUDY DESIGN, SIZE, DURATION CD73+CD90+CD105+ multipotent stem cells/progenitors (SC cohort) were isolated from endometrium (n = 18) and endometrioma (n = 11) of endometriosis patients as well as from the endometrium of healthy women (n = 14). Extensive phenotypic and functional analyses were performed in vitro on expanded multipotent stem cells/progenitors to confirm their altered characteristics. Aberrant gene signatures were also validated in paired-endometrium and -endometrioma tissue samples from another cohort (Tissue cohort, n = 19) of endometriosis patients. PARTICIPANTS/MATERIALS, SETTINGS, METHODS Paired-endometrial and -endometriotic biopsies were obtained from women with endometriosis (ASRM stage III–IV) undergoing laparoscopic surgery. Control endometria were obtained from healthy volunteers. Isolated CD73+CD90+CD105+ SC were evaluated for the presence of known endometrial surface markers, colony forming efficiency, multi-lineage differentiation, cell cycle distribution and 3D-spheroid formation capacity. Targeted RT-PCR arrays, along with hierarchical and multivariate clustering tools, were used to determine both intergroup and intragroup gene expression variability for stem cell and cancer-associated markers, in both SC+ and tissue cohorts. MAIN RESULTS AND THE ROLE OF CHANCE Isolated and expanded SC+ from both control and patient groups showed significantly higher surface expression of W5C5+, clonal expansion and 3D-spheroid formation capacity (P < 0.05) compared with SC−. The SC+ cells also undergo mesenchymal lineage differentiation, unlike SC−. Gene expression from paired-endometriosis samples showed significant downregulation of PTEN, ARID1A and TNFα (P < 0.05) in endometrioma compared with paired-endometrium SC+ samples. Hierarchical and multivariate clustering from both SC+ and tissue cohorts together identified 4 out of 30 endometrioma samples with aberrant expression of stem cell and cancer-associated genes, such as KIT, HIF2α and E-cadherin, altered expression ratio of ER-β/ER-α and downregulation of tumour suppressor genes (PTEN and ARID1A). Thus, we speculate that above changes may be potentially relevant to the development of EAOC. LARGE-SCALE DATA N/A. LIMITATIONS, REASON FOR CAUTION As the reported frequency of EAOC is very low, we did not have access to those samples in our study. Moreover, by adopting a targeted gene array approach, we might have missed several other potentially-relevant genes associated with EAOC pathogenesis. The above panel of markers should be further validated in archived tissue samples from women with endometriosis who later in life developed EAOC. WIDER IMPLICATIONS OF THE FINDINGS Knowledge gained from this study, with further confirmation on EAOC cases, may help in developing screening methods to identify women with increased risk of EAOC. STUDY FUNDING/COMPETING INTEREST(S) The study is funded by the Swedish Research Council (2012-2844), a joint grant from Stockholm County and Karolinska Institutet (ALF), RGD network at Karolinska Institutet, Karolinska Institutet for doctoral education (KID), Estonian Ministry of Education and Research (IUT34-16), Enterprise Estonia (EU48695), Horizon 2020 innovation program (WIDENLIFE, 692065), European Union’s FP7 Marie Curie Industry-Academia Partnerships and Pathways funding (IAPP, SARM, EU324509) and MSCA-RISE-2015 project MOMENDO (691058). All authors have no competing interest

Meta-signature of human endometrial receptivity : a meta-analysis and validation study of transcriptomic biomarkers

Previous transcriptome studies of the human endometrium have revealed hundreds of simultaneously up-and down-regulated genes that are involved in endometrial receptivity. However, the overlap between the studies is relatively small, and we are still searching for potential diagnostic biomarkers. Here we perform a meta-analysis of endometrial-receptivity associated genes on 164 endometrial samples (76 from 'pre-receptive' and 88 from mid-secretory, 'receptive' phase endometria) using a robust rank aggregation (RRA) method, followed by enrichment analysis, and regulatory microRNA prediction. We identify a meta-signature of endometrial receptivity involving 57 mRNA genes as putative receptivity markers, where 39 of these we confirm experimentally using RNA-sequencing method in two separate datasets. The meta-signature genes highlight the importance of immune responses, the complement cascade pathway and the involvement of exosomes in mid-secretory endometrial functions. Bioinformatic prediction identifies 348 microRNAs that could regulate 30 endometrial-receptivity associated genes, and we confirm experimentally the decreased expression of 19 microRNAs with 11 corresponding up-regulated meta-signature genes in our validation experiments. The 57 identified meta-signature genes and involved pathways, together with their regulatory microRNAs could serve as promising and sought-after biomarkers of endometrial receptivity, fertility and infertility.Peer reviewe

Human endometrial cell-type-specific RNA sequencing provides new insights into the embryo-endometrium interplay

STUDY QUESTION: Which genes regulate receptivity in the epithelial and stromal cellular compartments of the human endometrium, and which molecules are interacting in the implantation process between the blastocyst and the endometrial cells?SUMMARY ANSWER: A set of receptivity-specific genes in the endometrial epithelial and stromal cells was identified, and the role of galectins (LGALS1 and LGALS3), integrin beta 1 (ITGB1), basigin (BSG) and osteopontin (SPP1) in embryo-endometrium dialogue among many other protein-protein interactions were highlighted.WHAT IS KNOWN ALREADY: The molecular dialogue taking place between the human embryo and the endometrium is poorly understood due to ethical and technical reasons, leaving human embryo implantation mostly uncharted.STUDY DESIGN, SIZE, DURATION: Paired pre-receptive and receptive phase endometrial tissue samples from 16 healthy women were used for RNA sequencing. Trophectoderm RNA sequences were from blastocysts.PARTICIPANTS/MATERIALS, SETTING, METHODS: Cell-type-specific RNA-seq analysis of freshly isolated endometrial epithelial and stromal cells using fluorescence-activated cell sorting (FACS) from 16 paired pre-receptive and receptive tissue samples was performed. Endometrial transcriptome data were further combined in silico with trophectodermal gene expression data from 466 single cells originating from 17 blastocysts to characterize the first steps of embryo implantation. We constructed a protein-protein interaction network between endometrial epithelial and embryonal trophectodermal cells, and between endometrial stromal and trophectodermal cells, thereby focusing on the very first phases of embryo implantation, and highlighting the molecules likely to be involved in the embryo apposition, attachment and invasion.MAIN RESULTS AND THE ROLE OF CHANCE: In total, 499 epithelial and 581 stromal genes were up-regulated in the receptive phase endometria when compared to pre-receptive samples. The constructed protein-protein interactions identified a complex network of 558 prioritized protein-protein interactions between trophectodermal, epithelial and stromal cells, which were grouped into clusters based on the function of the involved molecules. The role of galectins (LGALS1 and LGALS3), integrin beta 1 (ITGB1), basigin (BSG) and osteopontin (SPP1) in the embryo implantation process were highlighted.LARGE SCALE DATA: RNA-seq data are available at www.ncbi.nlm.nih.gov/geo under accession number GSE97929.LIMITATIONS, REASONS FOR CAUTION: Providing a static snap-shot of a dynamic process and the nature of prediction analysis is limited to the known interactions available in databases. Furthermore, the cell sorting technique used separated enriched epithelial cells and stromal cells but did not separate luminal from glandular epithelium. Also, the use of biopsies taken from non-pregnant women and using spare IVF embryos (due to ethical considerations) might miss some of the critical interactions characteristic of natural conception only.WIDER IMPLICATIONS OF THE FINDINGS: The findings of our study provide new insights into the molecular embryo-endometrium interplay in the first steps of implantation process in humans. Knowledge about the endometrial cell-type-specific molecules that co-ordinate successful implantation is vital for understanding human reproduction and the underlying causes of implantation failure and infertility. Our study results provide a useful resource for future reproductive research, allowing the exploration of unknown mechanisms of implantation. We envision that those studies will help to improve the understanding of the complex embryo implantation process, and hopefully generate new prognostic and diagnostic biomarkers and therapeutic approaches to target both infertility and fertility, in the form of new contraceptives.Peer reviewe

A molecular tool for menstrual cycle phase dating of endometrial samples in endometriosis transcriptome studies

Correction: Volume: 101 Issue: 4 Pages: 868-868 DOI: 10.1093/biolre/ioz092Non peer reviewe