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Study Question: Can a panel of plasma protein biomarkers be identified to accurately and specifically diagnose endometriosis?, Summary Answer: A novel panel of 10 plasma protein biomarkers was identified and validated, demonstrating strong predictive accuracy for the diagnosis of endometriosis., What Is Known Already: Endometriosis poses intricate medical challenges for affected individuals and their physicians, yet diagnosis currently takes an average of 7 years and normally requires invasive laparoscopy. Consequently, the need for a simple, accurate non-invasive diagnostic tool is paramount., Study Design, Size, Duration: This study compared 805 participants across two independent clinical populations, with the status of all endometriosis and symptomatic control samples confirmed by laparoscopy. A proteomics workflow was used to identify and validate plasma protein biomarkers for the diagnosis of endometriosis., Participants/materials, Setting, Methods: A proteomics discovery experiment identified candidate biomarkers before a targeted mass spectrometry assay was developed and used to compare plasma samples from 464 endometriosis cases, 153 general population controls, and 132 symptomatic controls. Three multivariate models were developed: Model 1 (logistic regression) for endometriosis cases versus general population controls, Model 2 (logistic regression) for rASRM stage II to IV (mild to severe) endometriosis cases versus symptomatic controls, and Model 3 (random forest) for stage IV (severe) endometriosis cases versus symptomatic controls., Main Results and the Role of Chance: A panel of 10 protein biomarkers were identified across the three models which added significant value to clinical factors. Model 3 (severe endometriosis vs symptomatic controls) performed the best with an area under the receiver operating characteristic curve (AUC) of 0.997 (95% CI 0.994-1.000). This model could also accurately distinguish symptomatic controls from early-stage endometriosis when applied to the remaining dataset (AUCs ≥0.85 for stage I to III endometriosis). Model 1 also demonstrated strong predictive performance with an AUC of 0.993 (95% CI 0.988-0.998), while Model 2 achieved an AUC of 0.729 (95% CI 0.676-0.783)., Limitations, Reasons for Caution: The study participants were mostly of European ethnicity and the results may be biased from undiagnosed endometriosis in controls. Further analysis is required to enable the generalizability of the findings to other populations and settings., Wider Implications of the Findings: In combination, these plasma protein biomarkers and resulting diagnostic models represent a potential new tool for the non-invasive diagnosis of endometriosis., Study Funding/competing Interest(s): Subject recruitment at The Royal Women's Hospital, Melbourne, was supported in part by funding from the Australian National Health and Medical Research Council (NHMRC) project grants GNT1105321 and GNT1026033 and Australian Medical Research Future Fund grant no. MRF1199715 (P.A.W.R., S.H.-C., and M.H.). Proteomics International has filed patent WO 2021/184060 A1 that relates to endometriosis biomarkers described in this manuscript; S.B., R.L., and T.C. declare an interest in this patent. J.I., S.B., C.L., D.I., H.L., K.P., M.D., M.M., M.R., P.T., R.L., and T.C. are shareholders in Proteomics International. Otherwise, the authors have no conflicts of interest., Trial Registration Number: N/A., (© The Author(s) 2024. Published by Oxford University Press on behalf of European Society of Human Reproduction and Embryology.)

Endometriosis is a common condition associated with debilitating pelvic pain and infertility. A genome-wide association study meta-analysis, including 60,674 cases and 701,926 controls of European and East Asian descent, identified 42 genome-wide significant loci comprising 49 distinct association signals. Effect sizes were largest for stage 3/4 disease, driven by ovarian endometriosis. Identified signals explained up to 5.01% of disease variance and regulated expression or methylation of genes in endometrium and blood, many of which were associated with pain perception/maintenance (SRP14/BMF, GDAP1, MLLT10, BSN and NGF). We observed significant genetic correlations between endometriosis and 11 pain conditions, including migraine, back and multisite chronic pain (MCP), as well as inflammatory conditions, including asthma and osteoarthritis. Multitrait genetic analyses identified substantial sharing of variants associated with endometriosis and MCP/migraine. Targeted investigations of genetically regulated mechanisms shared between endometriosis and other pain conditions are needed to aid the development of new treatments and facilitate early symptomatic intervention., (© 2023. The Author(s), under exclusive licence to Springer Nature America, Inc.)

Endometriotic lesions are composed in part of endometrial-like stromal cells, however, there is a shortage of immortalized human endometrial stromal cultures available for research. As genetic factors play a role in endometriosis risk, it is important that genotype is also incorporated into analysis of pathological mechanisms. Human telomerase reverse transcriptase (hTERT) immortalization (using Lenti-hTERT-green fluorescent protein virus) took place following genotype selection; 13 patients homozygous for either the risk or non-risk 'other' allele for one or more important endometriosis risk single nucleotide polymorphism on chromosome 1p36.12 (rs3820282, rs56318008, rs55938609, rs12037376, rs7521902 or rs12061255). Short tandem repeat DNA profiling validated that donor tissue matched that of the immortalized cell lines and confirmed that cultures were genetically novel. Expression of morphological markers (vimentin and cytokeratin) and key genes of interest (telomerase, estrogen and progesterone receptors and LINC00339) were examined and functional assays for cell proliferation, steroid hormone and inflammatory responses were performed for 7/13 cultures. All endometrial stromal cell lines maintained their fibroblast-like morphology (vimentin-positive) and homozygous endometriosis-risk genotype following introduction of hTERT. Furthermore, the new stromal cultures demonstrated positive and diverse responses to hormones (proliferation and decidualisation changes) and inflammation (dose-dependent response), while maintaining hormone receptor expression. In conclusion, we successfully developed a range of human endometrial stromal cell lines that carry important endometriosis-risk alleles. The wider implications of this approach go beyond advancing endometriosis research; these cell lines will be valuable tools for multiple endometrial pathologies offering a level of genetic and phenotypic diversity not previously available., (© The Author(s) 2019. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Background: Common complications of pregnancy arise in part from dysfunctional placental development, and include gestational diabetes mellitus (GDM), intrauterine growth restriction (IUGR) and preeclampsia (PE). Peroxisome proliferator-activated receptors (PPARs), and their partner retinoid X receptor a (RXRalpha), mediate trophoblast differentiation and thus may offer insight into the pathophysiology of these diseases., Methods: Human placentae were obtained from women at term with GDM and were compared to uncomplicated term placentae. Placentae from women who delivered preterm with IUGR, PE or co-existing PE and IUGR were compared to matched controls. Quantitative RT-PCR and Western blotting were used to examine mRNA and protein expression of PPARalpha, PPARdelta, PPARgamma and RXRalpha. DNA binding activity of PPAR isoforms were measured in nuclear protein extracts., Results: GDM was associated with significantly lower placental PPARgamma mRNA and protein, PPARalpha protein and RXRalpha protein expression, while PPAR DNA binding activity remained unchanged. Placentae from women with PE did not demonstrate any changes in mRNA or protein expression or PPAR DNA binding activity, while IUGR/PE placenta showed significant increases in PPARalpha protein, PPARgamma mRNA and protein and RXRalpha mRNA and protein expression. Significantly elevated protein expression of PPARalpha and RXRalpha were associated with IUGR placentae. IUGR and IUGR/PE placentae had significantly higher PPARgamma DNA binding activity compared to controls., Conclusions: The data presented herein suggest that PPARs may be involved in the pathophysiology of GDM, PE and IUGR., (Crown Copyright 2009. Published by Elsevier Ltd. All rights reserved.)

Peroxisome proliferator-activated receptors (PPARs) and their transcriptional partner retinoid X receptor (RXR) are involved in transcriptionally regulating the events that contribute to the control of parturition in humans. Definitive data, however, are lacking with respect to PPAR and RXR expression and activation during term labour in human gestational tissues. The aim of this study, therefore, was to identify tissue and labour-associated changes of PPAR isoforms (alpha, delta and gamma) and RXRalpha in placenta, amnion and choriodecidua. Gestational tissues from term non-labouring women were used for immunohistochemistry localisation and confirmation studies of PPAR isoforms (alpha, delta and gamma) and RXRalpha. Human gestational tissues were then collected from term women not-in-labour (NIL) (elective Caesarean section), in-labour (IL) (emergency Caesarean section) and post-labour (PL) (normal vaginal delivery). Quantitative RT-PCR (qRT-PCR) and Western blotting were employed to study mRNA and protein expression profiles respectively. Significantly higher mRNA expression was observed in placental tissues taken from women in labour (PPARdelta, PPARgamma and RXRalpha). Elevated PPARdelta and RXRalpha mRNA expression in fetal membranes was also associated with being in labour. In contrast, PPARgamma mRNA in the amnion was decreased with term PL compared to NIL. In placenta, PPARalpha, PPARdelta and PPARgamma protein expression was significantly increased in the IL group compared to the NIL or PL group. There was no significant difference in PPAR or RXRalpha protein expression in both amnion and choriodecidua between the three labour groups. PPAR (alpha and gamma) transcription factor DNA binding activity was found to decline IL compared to NIL and PL in the placenta. PPARdelta DNA binding activity also decreased in the choriodecidua IL compared to PL. In amnion, PPARalpha DNA binding activity was found to be higher IL compared to NIL. In conclusion, term human labour is associated with changes in expression and activity of PPAR isoforms and its transcription partner, RXRalpha. This data is consistent with the hypothesis that PPAR:RXR are involved in regulating of the processes of human term parturition.

To generate new insights into the process of fetal membrane rupture, we have developed a technique whereby fetal membranes overlying the cervix (i.e. supracervical site, SCS) are tagged in women undergoing term elective Caesarean section. The specific aim is to determine the effect of supracervical apposition on the release of inflammatory mediators and NF-kappaB signalling in pre-labour fetal membranes. Fetal membranes were collected from both the SCS and from a distal site (DS). The level of NF-kappaB proteins and its transcriptional co-activator protein CBP and p300 was determined by Western blotting and/or immunohistochemistry (IHC), and cytokine and prostaglandin release was quantified by enzyme immunoassay. Tissues obtained before labour at term possess an area of the fetal membranes (i.e. supracervical site) that exhibit decreased release of IL-1beta, IL-6, IL-8, TNF-alpha and PGE(2). IHC revealed that NF-kappaB signalling proteins, CBP and p300 were significantly increased in SC fetal membranes compared to distal membranes. In summary, data from this study confirm that supracervical fetal membranes display altered structural and biochemical characteristics.