Circulating microRNAs as Non-Invasive Biomarkers in Endometriosis Diagnosis-A Systematic Review.

The aim of this systematic review is to assess the power of circulating miRNAs as biomarkers as a diagnostic tool in endometriosis. In endometriosis-suspected women with uncertain imaging, the only way to confirm or exclude endometriosis with certainty is currently laparoscopy. This creates a need for non-invasive diagnostics. We searched the literature through the PubMed database using the Mesh terms 'endometriosis' and 'miRNAs'. Some, but limited, overlap was found between the 32 articles included, with a total of 20 miRNAs reported as dysregulated in endometriosis in two or more studies. MiR-17-5p was reported as dysregulated in six studies, followed by miR-451a and let-7b-5p in four studies and miR-20a-5p, miR-143-3p, miR-199a-5p and miR-3613-5p in three studies. Furthermore, a possible impact of the menstrual phase on miRNA expression was noted in five studies, while no influence of hormonal intake was observed in any included study. The modest reproducibility between studies may be attributable to biological variability as well as to the lack of universal protocols, resulting in pre- and analytical variability. Despite the identification of several suitable candidate biomarkers among the miRNAs, the need for high-quality studies with larger and well-defined population cohorts and the use of standardized protocols lingers.

Systematic reviews on platelet transfusions: Is there unnecessary duplication of effort? A scoping review.

BACKGROUND AND OBJECTIVES: Platelet transfusions are used across multiple patient populations to prevent and correct bleeding. This scoping review aimed to map the currently available systematic reviews (SRs) and evidence-based guidelines in the field of platelet transfusion. MATERIALS AND METHODS: A systematic literature search was conducted in seven databases for SRs on effectiveness (including dose and timing, transfusion trigger and ratio to other blood products), production modalities and decision support related to platelet transfusion. The following data were charted: methodological features of the SR, population, concept and context features, outcomes reported, study design and number of studies included. Results were synthesized in interactive evidence maps. RESULTS: We identified 110 SRs. The majority focused on clinical effectiveness, including prophylactic or therapeutic transfusions compared to no platelet transfusion (34 SRs), prophylactic compared to therapeutic-only transfusion (8 SRs), dose, timing (11 SRs) and threshold for platelet transfusion (15 SRs) and the ratio of platelet transfusion to other blood products in massive transfusion (14 SRs). Furthermore, we included 34 SRs on decision support, of which 26 evaluated viscoelastic testing. Finally, we identified 22 SRs on platelet production modalities, including derivation (4 SRs), pathogen inactivation (6 SRs), leucodepletion (4 SRs) and ABO/human leucocyte antigen matching (5 SRs). The SRs were mapped according to concept and clinical context. CONCLUSION: An interactive evidence map of SRs and evidence-based guidelines in the field of platelet transfusion has been developed and identified multiple reviews. This work serves as a tool for researchers looking for evidence gaps, thereby both supporting research and avoiding unnecessary duplication.

Impact of disasters on blood donation rates and blood safety: A systematic review and meta-analysis.

BACKGROUND AND OBJECTIVES: Timely and adequate access to safe blood forms an integral part of universal health coverage, but it may be compromised by natural or man-made disasters. This systematic review provides an overview of the best available scientific evidence on the impact of disasters on blood donation rates and safety outcomes. MATERIALS AND METHODS: Five databases (The Cochrane Library, MEDLINE, Embase, Web of Science and CINAHL) were searched until 27 March 2020 for (un)controlled studies investigating the impact of disasters on blood donation rates and/or safety. Risk of bias and overall certainty of the evidence were assessed using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach. RESULTS: Eighteen observational studies were identified, providing very low certainty of evidence (due to high risk of bias, inconsistency and/or imprecision) on the impact of natural (12 studies) and man-made/technological (6 studies) disasters. The available evidence did not enable us to form any generalizable conclusions on the impact on blood donation rates. Meta-analyses could not detect any statistically significant changes in transfusion-transmissible infection (TTI) rates [hepatitis B virus (HBV), hepatitis C virus (HCV), human immunodeficiency virus (HIV)-1/2, human T-lymphotropic virus I and II (HTLV-I/II) and syphilis] in donated blood after a disaster, either in first-time or repeat donors, although the evidence is very uncertain. CONCLUSION: The very low certainty of evidence synthetized in this systematic review indicates that it is very uncertain whether there is an association between disaster occurrence and changes in TTI rates in donated blood. The currently available evidence did not allow us to draw generalizable conclusions on the impact of disasters on blood donation rates.

Day care as a strategy for drowning prevention in children under 6 years of age in low- and middle-income countries.

BACKGROUND: Drowning is responsible for an estimated 320,000 deaths a year, and over 90% of drowning mortality occurs in low- to middle-income countries (LMICs), with peak drowning rates among children aged 1 to 4 years. In this age group, mortality due to drowning is particularly common in rural settings and about 75% of drowning accidents happen in natural bodies of water close to the home. Providing adequate child supervision can protect children from drowning, and organized formal day care programs could offer a way to achieve this. OBJECTIVES: Primary objective • To assess the effects of day care programs for children under 6 years of age on drowning-related mortality or morbidity, or on total drowning accidents (fatal and non-fatal), in LMICs, compared to no day care programs or other drowning prevention interventions Secondary objectives • To assess the effects of day care programs in LMICs for children under 6 years of age on unsafe water exposure • To assess safety within these programs (e.g. transmission of infection within day care, physical or sexual abuse of children within day care) • To assess the incidence of unintentional injury within these programs • To describe the cost-effectiveness of such programs, in relation to averted drowning-related mortality or morbidity SEARCH METHODS: On November 23, 2019, and for an update on August 18, 2020, we searched MEDLINE (PubMed), Embase, CENTRAL, ERIC, and CINAHL, as well as two trial registries. On December 16, 2019, and for an update on February 9, 2021, we searched 12 other resources, including websites of organizations that develop programs targeted to children. SELECTION CRITERIA: We included randomized, quasi-randomized, and non-randomized controlled studies (with explicitly listed specific study design features) that implemented formal day care programs as a single program or combined with additional out-of-day care components (such as educational activities aimed at preventing injury or drowning or early childhood development activities) for children of preschool age (below 6 years of age) in LMICs for comparison with no such programs or with other drowning prevention interventions. Studies had to report at least one outcome related to drowning or injury prevention for the children enrolled. DATA COLLECTION AND ANALYSIS: Two review authors independently performed study selection and data extraction, as well as risk of bias and GRADE assessment. MAIN RESULTS: Two non-randomized observational studies, conducted in rural Bangladesh, involving a total of 252,631 participants, met the inclusion criteria for this review. One of these studies compared a formal day care program combined with parent education, playpens provided to parents, and community-based activities as additional out-of-day care components versus no such program. Overall we assessed this study to be at moderate risk of bias (moderate risk of bias due to confounding, low risk of bias for other domains). This study showed that implementation of a formal day care program combined with parent education, provision of playpens to parents, and community-based activities, in a rural area with a high drowning incidence, likely reduces the risk of death from drowning over the study period of 4 years and 8 months compared to no day care program (hazard ratio 0.18, 95% confidence interval [CI] 0.06 to 0.58; 1 study, 136,577 participants; moderate-certainty evidence). Drowning morbidity (non-fatal drowning resulting in complications), total drowning (fatal and non-fatal), unsafe water exposure, and program safety (e.g. transmission of infection within day care, physical or sexual abuse of children within day care) were not reported, nor was the incidence of other unintentional injuries. Cost-effectiveness was reported as 812 USD (95% CI 589 to 1777) per disability-adjusted life-year averted as a consequence of drowning (moderate-certainty evidence). The second study compared day care programs with or without playpens provided to parents as an additional component versus only playpens provided to parents as an alternative drowning prevention intervention. Overall we assessed the study to be at critical risk of bias because we judged bias due to confounding to be at critical risk. As the certainty of evidence was very low, we are uncertain about the effects on drowning mortality rate of implementing a day care program compared to providing playpens (rate ratio 0.25, 95% CI 0.15 to 0.41; 1 study; 76,575 participants; very low-certainty evidence). Likewise, we are uncertain about the effects of a day care program with playpens provided as an additional component versus playpens provided alone (rate ratio 0.06, 95% CI 0.02 to 0.12; 1 study, 45,460 participants; very low-certainty evidence). The other outcomes of interest - drowning morbidity, total drowning, unsafe water exposure, program safety, incidence of other unintentional injuries, and cost-effectiveness - were not reported. AUTHORS' CONCLUSIONS: This review provides evidence suggesting that a day care program with additional out-of-day care components such as community-based education, parent education, and playpens provided to parents likely reduces the drowning mortality risk in regions with a high burden of drowning compared to no intervention.

2020 International Consensus on First Aid Science With Treatment Recommendations.

This is the summary publication of the International Liaison Committee on Resuscitation's 2020 International Consensus on First Aid Science With Treatment Recommendations. It addresses the most recent published evidence reviewed by the First Aid Task Force science experts. This summary addresses the topics of first aid methods of glucose administration for hypoglycemia; techniques for cooling of exertional hyperthermia and heatstroke; recognition of acute stroke; the use of supplementary oxygen in acute stroke; early or first aid use of aspirin for chest pain; control of life- threatening bleeding through the use of tourniquets, haemostatic dressings, direct pressure, or pressure devices; the use of a compression wrap for closed extremity joint injuries; and temporary storage of an avulsed tooth. Additional summaries of scoping reviews are presented for the use of a recovery position, recognition of a concussion, and 6 other first aid topics. The First Aid Task Force has assessed, discussed, and debated the certainty of evidence on the basis of Grading of Recommendations, Assessment, Development, and Evaluation criteria and present their consensus treatment recommendations with evidence-to-decision highlights and identified priority knowledge gaps for future research. The 2020 International Consensus on Cardiopulmonary Resuscitation (CPR) and Emergency Cardiovascular Care (ECC) Science With Treatment Recommendations (CoSTR) is the fourth in a series of annual summary publications from the International Liaison Committee on Resuscitation (ILCOR). This 2020 CoSTR for first aid includes new topics addressed by systematic reviews performed within the past 12 months. It also includes updates of the first aid treatment recommendations published from 2010 through 2019 that are based on additional evidence evaluations and updates. As a result, this 2020 CoSTR for first aid represents the most comprehensive update since 2010.

Storage of an avulsed tooth prior to replantation: A systematic review and meta-analysis.

BACKGROUND/AIM: It is crucial to store an avulsed tooth appropriately to preserve the viability of the periodontal ligament cells prior to replantation. The aim of this systematic review was to identify the best available evidence for the effectiveness of any technique available to laypeople for storing an avulsed tooth compared with storage in milk or saliva. METHODS: The following databases were searched (September 2019): Cochrane Library, MEDLINE, and Embase. Two reviewers independently considered trial eligibility, then extracted and analyzed data, and assessed the risk of bias. The certainty of the body of evidence was appraised according to the GRADE methodology. RESULTS: Out of 4118 references, 33 studies were included and reported 23 comparisons of which 10 were synthesized in a meta-analysis. The limited evidence available favors storing an avulsed tooth in Hank's balanced salt solution (pooled SMD 2.47, 95% CI [1.59;3.34], P < .00001), propolis solution (pooled SMD 1.73, 95% CI [1.12;2.33], P < .00001), oral rehydration salts (pooled SMD 4.16, 95% CI [2.10;6.23], P < .0001), rice water, and cling film compared with storage in milk. The cell viability rate was significantly lower in teeth stored in saline solutions (pooled SMD -4.35, 95% CI [-7.55;-1.14], P = .008), tap water, buttermilk, castor oil, GC Tooth Mousse, and turmeric extract than those stored in milk. There is insufficient evidence to recommend for or against temporary storage of an avulsed tooth in saliva compared with alternative solutions. The certainty of evidence was considered low to very low due to limitations in study design, indirect study populations and outcome measures, and imprecision. CONCLUSION: Although milk was shown to extend the periodontal ligament cell viability before replantation compared with saline or tap water, the following media have also demonstrated efficacy at preserving the cell viability: Hank's balanced salt solution, propolis, oral rehydration salts, rice water, and cling film.

The Use of Antibody Arrays in the Discovery of New Plasma Biomarkers for Endometriosis.

A noninvasive diagnostic test for endometriosis is needed to shorten the current diagnostic delay of 8-11 years. The goal of this study was to discover new biomarkers for endometriosis using an antibody array approach. A total of 103 plasma samples from patients with laparoscopically confirmed presence (n = 68) or absence (n = 35) of endometriosis were selected. Samples were pooled according to disease status, cycle phase, disease stage, and phenotype. Pooled samples were screened for possible biomarkers using the L-series 1000 and Quantibody 660 arrays from RayBiotech. Technical verification of ten markers was done using a custom-made multiplex immunoassay identifying ten proteins (10-plex) and later by single ELISA. Due to the limited reproducibility of the L-series 1000 immunoassay, the biomarker screening was performed using the Quantibody 660, a sandwich-based multiplex immunoassay, which showed that 280 proteins were upregulated, and 29 proteins downregulated in the endometriosis pool versus the control pool. In order to assess the reproducibility of these results, ten preselected proteins were analyzed using a custom 10-plex. Four proteins (CD48, DNAM-1, IL-31, and XIAP) were confirmed to be differentially expressed when comparing the endometriosis and control pool. However, only IL-31 showed a univariate statistical difference between endometriosis and control groups in individual samples that were part of the initial pools. In conclusion, discovery and verification of potential markers proved challenging using multiplex immunoassay methods, mainly due to issues with reproducibility. Only IL-31 showed potential as possible biomarker for endometriosis.

Technical Verification and Assessment of Independent Validation of Biomarker Models for Endometriosis.

There is a great need for a noninvasive diagnosis for endometriosis. Several biomarkers and biomarker panels have been proposed. Biomarker models consisting of CA-125, VEGF, Annexin V, and glycodelin/sICAM-1 were previously developed by our group. The objective of our current study was to assess the impact of technical and biological variability on the performance of those previously developed prediction models in a technical verification and a validation setting. The technical verification cohort consisted of peripheral blood plasma samples from a subset of the patients included in the original study of Vodolazkaia et al. (99 women with and 37 women without endometriosis). The validation study was done in plasma samples of an independent patient cohort (170 women with and 86 women without endometriosis). Single immunoassays were used for CA-125, VEGF-A, sICAM-1, Annexin V, and glycodelin. Statistical analyses were done using univariate and multivariate (logistic regression) approaches. The previously reported prediction models for endometriosis had a low performance in both the technical verification and validation setting. New prediction models were developed, which included CA-125, Annexin V, and sICAM-1, but CA-125 was the only marker that was retained in the models across the technical verification and validation study. Overall, successful validation of a biomarker model depends on several factors such as patient selection, collection methods, assay selection/handling, stability of the marker, and statistical analysis and interpretation. There is a need for standardized studies in large, well-defined patient cohorts with robust assay methodologies.

Lack of an Association between a Polymorphism in the KRAS 3' Untranslated Region (rs61764370) and Endometriosis in a Large European Case-Control Study.

BACKGROUND: Endometriosis is a common disorder that affects 6-10% of reproductive age women. In a previous study, we demonstrated that a polymorphism in let-7 microRNA-binding site in the 3' untranslated region of the KRAS gene was found in 31% of subjects with endometriosis resistant to medical therapy. This polymorphism was now tested in a large, case-control study. METHODS: Peripheral blood or peritoneal biopsies from 2,077 European subjects with or without endometriosis and known infertility were tested for the presence of the variant allele using polymerase chain reaction. RESULTS: Histologically proven endometriosis was found in 1,140 subjects, while 937 subjects were disease free. Variant allele carrier rates in subjects with and without endometriosis were 15.7 and 15.1%, respectively. No association between the variant KRAS allele and stage of the disease, age at surgery, body mass index, or type of infertility was identified. CONCLUSION: A germ-line single-nucleotide polymorphism in the let-7 microRNA-binding site of the KRAS gene was not associated with sporadic endometriosis in an infertile Caucasian population in this large case-control study. However, it remains possible that this gene variant may be a marker of treatment resistance. Further studies on the role of this polymorphism in endometriosis are needed.

Endometriosis biomarkers: Will codevelopment in academia-industry partnerships result in new and robust noninvasive diagnostic tests?

Endometriosis is an important gynecological disease, affecting 10% of reproductive age women, and associated with pain, infertility, reduced quality of life, and high health economic cost. Except for ultrasound detection of ovarian endometriotic cysts, the gold standard for diagnosis is laparoscopy, leading to diagnostic delays of 5-10 years. Accurate noninvasive biomarkers are needed, especially for symptomatic women with a normal gynecological ultrasound, to triage them towards medical or surgical treatment and to monitor their treatment outcome. Such biomarkers are not available today, largely because the research focus has been on discovery, not on reproducibility and validation. Academia/industry partnerships can move this field forward by validation of promising markers, consensus on endometriosis phenotypes/controls and desirable accuracy (sensitivity/specificity). Such partnerships should increase the quality and reproducibility of target discovery work and foster global consensus on the use of relevant preclinical/animal models, if they are managed with complete (financial) transparency and with the aim to translate innovation into products benefiting patients. It is essential that mutual objectives are clarified between industry and academia partners including intellectual property policy, critical decision points, funding agreements, milestones and timelines, with a clear strategy for project termination/change of strategy, a restriction on publications till new discoveries have been patented, considering that a minority of novel findings can be translated into new therapeutic targets, diagnostics, or marketed products.

Telomerase Reverse Transcriptase Expression in Mouse Endometrium During Reepithelialization and Regeneration in a Menses-Like Model.

The regenerative capacity of the endometrium has been attributed to resident stem/progenitor cells. A number of stem/progenitor markers have been reported for human endometrial stem/progenitor cells; however, the lack of convenient markers in the mouse has made experimental investigation into endometrial regeneration difficult. We recently identified endometrial epithelial, endothelial, and immune cells, which express a reporter for the stem/progenitor marker, mouse telomerase reverse transcriptase (mTert). In this study, we investigate the expression pattern of a green fluorescent protein (GFP) reporter for mTert promoter activity (mTert-GFP) in endometrial regeneration following a menses-like event. mTert-GFP expression marks subepithelial populations of T cells and mature macrophages and may play a role in immune cell regulated repair. Clusters of mTert-GFP-positive epithelial cells were identified close to areas of reepithelialization and possibly highlight a role for mTert in the repair and regeneration of the endometrial epithelium.

Functional Expression of TRP Ion Channels in Endometrial Stromal Cells of Endometriosis Patients.

Endometriosis is a common gynecological disease that is characterized by the presence of functional endometrial-like lesions in the abdominal cavity. Aside from epithelial cells, these lesions consist of stromal cells that have the capacity to migrate, adhere, proliferate, and induce neuro- and lymphangiogenesis, which allows them to survive at ectopic locations. However, the exact underlying mechanisms that regulate these changes are yet to be elucidated. The common ground of these processes, however, is the second messenger, calcium. In this regard, members of the superfamily of transient receptor potential (TRP) ion channels, which are known to be calcium-permeable and expressed in the endometrium, have emerged as key regulators. Here, we assessed the molecular and functional expression of TRP channels in stromal cells isolated from the eutopic endometrium of endometriosis patients and controls. Using RT-qPCR, high mRNA levels of TRPV2, TRPV4, TRPM4, TRPM7, TRPC1, TRPC3, TRPC4, and TRPC6 were observed in the whole endometrium throughout the menstrual cycle. Additionally, and in line with previous reports of control patients, TRPV2, TRPV4, TRPC1/4, and TRPC6 were present in human endometrial stromal cells (hESC) from endometriosis patients both at the molecular and functional level. Moreover, proliferation and migration assays illustrated that these parameters were not affected in stromal cells from endometriosis patients. Furthermore, comparison between eutopic and ectopic endometrial samples revealed that the RNA expression pattern of TRP channels did not differ significantly. Collectively, although a functional expression of specific ion channels in hESCs was found, their expression did not correlate with endometriosis.

Noninvasive diagnosis of endometriosis: Review of current peripheral blood and endometrial biomarkers.

A noninvasive biomarker-based test could help shorten the diagnostic delay for endometriosis. The most investigated biomarker sources are peripheral blood and endometrium. Discovery of endometriosis biomarkers is often hypothesis-driven, i.e. when one or a few biomarkers are investigated based on their role in the disease pathogenesis. Alternatively, a hypothesis-generating approach has been followed using the "omics" technologies. A variety of biomarkers for endometriosis have been investigated, but no biomarker has been validated for clinical use. Many challenges lie ahead in the endometriosis biomarker field. In the future, harmonized collection and reporting methods should allow large-scale international collaboration for highly powered studies.

Endometrial stem/progenitor cells and their role in the pathogenesis of endometriosis.

Human endometrium regenerates on a cyclical basis each month, likely mediated by endometrial stem/progenitor cells. Several types of stem/progenitor cells have been identified: CD140b+CD146+ or SUSD2+ endometrial mesenchymal stem cells (eMSCs), N-cadherin+ endometrial epithelial progenitor cells (eEPs), and side population (SP) cells, a heterogeneous population predominantly comprising endothelial cells. eMSCs reside in a perivascular niche and likely mediate angiogenesis and stromal regeneration. Human eEPs are located in the bases of glands in the basalis and are likely more primitive than SSEA-1+ basalis epithelial cells. Endometrial stem/progenitor cells may contribute to the pathogenesis of endometriosis by their retrograde shedding into the pelvic cavity, either after menarche or as a result of neonatal uterine bleeding. eMSCs may have a role in the generation of progesterone-resistant phenotype of endometrial stromal fibroblasts (eSFs) in endometriosis. In future clinical practice, endometrial stem/progenitor cells may be used to establish diagnosis of endometriosis or as therapeutic targets.

Optimization of Endometrial Decidualization in the Menstruating Mouse Model for Preclinical Endometriosis Research.

BACKGROUND: To induce endometrial decidualization in rodents, an intrauterine oil stimulus can be delivered via the nontraumatic vagina or via the traumatic laparotomy. However, there is considerable variation in amount of decidualization using these inducing methods. Therefore, we studied which oil delivery route could achieve the highest rate of endometrial decidualization along the full length of both uterine horns. METHODS: To induce decidualization, ovariectomized C57Bl/6J mice were injected with estrogen (100 ng/day; 3 days). A progesterone pellet (5 mg) was implanted subcutaneously, followed by estrogen injections (5 ng/day; 3 days). Oil (20 µL/horn) was injected in the uterus via laparotomy, laparoscopy, or vagina. Four days later, the pellet was removed, followed by hysterectomy after 4 to 6 hours. Endometrial decidualization was evaluated macroscopically and microscopically using hematoxylin and eosin and desmin staining. Furthermore, uterine weight and hormone levels were measured. RESULTS: The proportion of animals with macroscopic bicornuate decidualization was higher after laparoscopic (83%) and laparotomic (89%) injection than after sham injection (11%). Furthermore, macroscopic bicornuate decidualization was significantly higher after laparotomic injection (89%) compared to the vaginal injection (38%). Uterine weight and endometrial surface area were significantly higher in both laparotomy and laparoscopy groups compared to the sham group, while the relative desmin-positive endometrial surface area was only significantly different between the laparotomy and the sham animals. CONCLUSION: Methods using laparoscopic and laparotomic intrauterine oil injection resulted in a higher amount of decidualized endometrium compared to sham injection, although further optimization is needed to reach full bicornuate decidualization.

Of Mice and Women: A Laparoscopic Mouse Model for Endometriosis.

STUDY OBJECTIVE: To demonstrate how a novel laparoscopic approach allows the development of a mouse model for endometriosis after seeding menstrual endometrium from donor mice into the abdominal cavity of syngeneic recipient mice. DESIGN: A step-by-step video description of the techniques used to adapt the estrous cycle of mice towards a menstrual cycle and to subsequently induce endometriosis via laparoscopic seeding of menstrual endometrium. SETTING: University research institute. ETHICS: All animal experiments were ethically approved by KU Leuven, Belgium (ethical approval number: P031/2013). INTERVENTIONS, MEASUREMENTS, AND MAIN RESULTS: Oophorectomized female C57BL/6JRj mice received a series of estrogen injections. Next, a progesterone pellet was administered, together with a second series of estrogen injections. In addition, decidualization of the endometrium was induced with an intrauterine sesame oil stimulus. Four days later the progesterone pellet was removed and menstruation started [1]. Five hours after the progesterone pellet was removal the uterus was harvested, and the menstrual endometrium was dissected and seeded into the abdominal cavity of syngeneic recipient mice to induce endometriosis [2] using a laparoscopic approach [3]. Uterus and lesions were removed from the recipient mice 1 week after induction, and tissues were immunohistochemically stained for H&E, vimentin, and cytokeratin. CONCLUSION: In this video we show a novel methodology to induce endometriosis in mice using laparoscopic inoculation of syngeneic menstrual endometrium, mimicking Sampson's theory of retrograde menstruation [4]. Compared with currently available rodent models, our model offers a less invasive and more physiologic way for fundamental and preclinical endometriosis research, with a high endometriosis incidence and lesion take rate.

Evaluation of Total, Active, and Specific Myeloperoxidase Levels in Women with and without Endometriosis.

Myeloperoxidase (MPO) is a proinflammatory enzyme and a marker for neutrophil activation and oxidative stress. Since oxidative stress and inflammation are linked to the pathogenesis of endometriosis, we hypothesized that the total, active, and specific (active/total) MPO levels were significantly different in plasma of women with and without endometriosis. Samples were selected from our biobank from women with endometriosis (n = 212) and controls without endometriosis (n = 121) across the menstrual cycle. Total MPO plasma levels were measured by immunoassay and MPO activity by enzymatic assay. Total and active MPO levels did not differ significantly among endometriosis cases and controls, whereas the specific MPO activity was significantly lower in women with endometriosis than that in controls (p = 0.0159). After the subdivision of control patients into women with a normal pelvis and women with other benign gynecological disorders, a significant difference was observed only between women with endometriosis and women with other benign gynecological disorders (p = 0.0266). In conclusion, systemic MPO levels may not be suited as a single biomarker for endometriosis. Our data support the involvement of MPO in other gynecological disorders but do not provide any evidence for an association with endometriosis.

Analysis of potential protein-modifying variants in 9000 endometriosis patients and 150000 controls of European ancestry.

Genome-wide association (GWA) studies have identified 19 independent common risk loci for endometriosis. Most of the GWA variants are non-coding and the genes responsible for the association signals have not been identified. Herein, we aimed to assess the potential role of protein-modifying variants in endometriosis using exome-array genotyping in 7164 cases and 21005 controls, and a replication set of 1840 cases and 129016 controls of European ancestry. Results in the discovery sample identified significant evidence for association with coding variants in single-variant (rs1801232-CUBN) and gene-level (CIITA and PARP4) meta-analyses, but these did not survive replication. In the combined analysis, there was genome-wide significant evidence for rs13394619 (P = 2.3 × 10-9) in GREB1 at 2p25.1 - a locus previously identified in a GWA meta-analysis of European and Japanese samples. Despite sufficient power, our results did not identify any protein-modifying variants (MAF > 0.01) with moderate or large effect sizes in endometriosis, although these variants may exist in non-European populations or in high-risk families. The results suggest continued discovery efforts should focus on genotyping large numbers of surgically-confirmed endometriosis cases and controls, and/or sequencing high-risk families to identify novel rare variants to provide greater insights into the molecular pathogenesis of the disease.

Meta-analysis identifies five novel loci associated with endometriosis highlighting key genes involved in hormone metabolism.

Endometriosis is a heritable hormone-dependent gynecological disorder, associated with severe pelvic pain and reduced fertility; however, its molecular mechanisms remain largely unknown. Here we perform a meta-analysis of 11 genome-wide association case-control data sets, totalling 17,045 endometriosis cases and 191,596 controls. In addition to replicating previously reported loci, we identify five novel loci significantly associated with endometriosis risk (P<5 × 10-8), implicating genes involved in sex steroid hormone pathways (FN1, CCDC170, ESR1, SYNE1 and FSHB). Conditional analysis identified five secondary association signals, including two at the ESR1 locus, resulting in 19 independent single nucleotide polymorphisms (SNPs) robustly associated with endometriosis, which together explain up to 5.19% of variance in endometriosis. These results highlight novel variants in or near specific genes with important roles in sex steroid hormone signalling and function, and offer unique opportunities for more targeted functional research efforts.

Endometriosis is associated with aberrant metabolite profiles in plasma.

OBJECTIVE: To identify metabolites that are associated with and predict the presence of endometriosis. DESIGN: Metabolomics study using state-of-the-art mass spectrometry approaches. SETTING: University hospital and universities. PATIENT(S): Twenty-five women with laparoscopically confirmed endometriosis (cases) and 19 women with laparoscopically documented absence of endometriosis (controls). None of the women included in this study had received oral contraception or GnRH agonists for a minimum of 1 month before blood collection. INTERVENTION(S): Plasma collection. MAIN OUTCOME MEASURE(S): Metabolite profiles were generated and interrogated using multiple mass spectrometry methods, that is, high performance liquid chromatography coupled with negative mode electrospray ionization tandem mass spectrometry, UPLC-MS/MS, and ultra performance liquid chromatography-electroSpray ionization-quadrupole time-of-flight (UPLC-ESI-Q-TOF). Metabolite groups investigated included phospholipids, glycerophospholipids, ether-phospholipids, cholesterol-esters, triacylglycerol, sphingolipids, free fatty acids, steroids, eicosanoids, and acylcarnitines. RESULT(S): A panel of acylcarnitines predicted the presence of endometriosis with 88.9% specificity and 81.5% sensitivity in human plasma, with a positive predictive value of 75%. However, due to data limitations the outcome of the receiver operating characteristic curve analysis was not significant. CONCLUSION(S): A diagnostic model based on acylcarnitines has the potential to predict the presence and stage of endometriosis.