Biomarkers for the Noninvasive Diagnosis of Endometriosis: State of the Art and Future Perspectives

Transvaginal ultrasound and magnetic resonance imaging in the diagnosis of endometrioma: a systematic review and meta-analysis of diagnostic test accuracy studies

INTRODUCTION

The diagnosis of endometriomas in patients with endometriosis is of primary importance because it influences the management and prognosis of infertility and pain. Imaging techniques are evolving constantly. This study aimed to systematically assess the diagnostic accuracy of transvaginal ultrasound (TVUS) and magnetic resonance imaging (MRI) in detecting endometrioma using the surgical visualisation of lesions with or without histopathological confirmation as reference standards in patients of reproductive age with suspected endometriosis.

METHODS

PubMed, Embase, Web of Science, Cumulative Index to Nursing and Allied Health Literature and ClinicalTrials.gov databases were searched from their inception to 12 October 2022, using a manual search for additional articles. Two authors independently performed title, abstract and full-text screening of the identified records, extracted study details and quantitative data and assessed the quality of the studies using the 'Quality Assessment of Diagnostic Accuracy Study 2' tool. Bivariate random-effects models were used to determine the pooled sensitivity and specificity, compare the two imaging modalities and evaluate the sources of heterogeneity.

RESULTS

Sixteen prospective studies (10 assessing TVUS, 4 assessing MRI and 2 assessing both TVUS and MRI) were included, representing 1976 participants. Pooled TVUS and MRI sensitivities for endometrioma were 0.89 (95% confidence interval 'CI', 0.86-0.92) and 0.94 (95% CI, 0.74-0.99), respectively (indirect comparison p-value of 0.47). Pooled TVUS and MRI specificities for endometrioma were 0.95 (95% CI, 0.92-0.97) and 0.94 (95% CI, 0.89-0.97), respectively (indirect comparison p-value of 0.51). These studies had a high or unclear risk of bias. A direct comparison (all participants undergoing TVUS and MRI) of the modalities was available in only two studies.

CONCLUSION

TVUS and MRI have high accuracy for diagnosing endometriomas; however, high-quality studies comparing the two modalities are lacking.

Cytokine and chemokine profiles in women with endometriosis, polycystic ovary syndrome, and unexplained infertility

Numerous factors (including immunological, congenital, hormonal, and morphological disorders) can lead to infertility. In this regard, 3 specific diseases associated with infertility are discussed in this review study (i.e., polycystic ovary syndrome [PCOS], endometriosis [EMS], and unexplained infertility [UI]). PCOS is a common endocrine disorder characterized by chronic low-grade inflammation, and EMS is a benign disease characterized by the presence of ectopic endometrial tissue. UI refers to couples who are unable to conceive for no known reason. Conception and pregnancy are significantly affected by the immune system; in this regard, chemokines and cytokines play important roles in the regulation of immune responses. Patients with PCOS, EMS, and UI have altered cytokine and chemokine profiles, suggesting that dysregulation of these molecules may contribute to infertility in these conditions. Accordingly, the issue of infertility is addressed in this review study, a condition that affects approximately 16% of couples worldwide.

Research Progress of Caspase in Endometriosis

Endometriosis, a common chronic gynecological disease, refers to the presence and proliferation of endometrial tissue in locations other than the uterine cavity. Approximately 6 to 10% of the population of women of childbearing age are known to have endometriosis; the most common clinical signs are pelvic pain and infertility. Although endometriosis is a benign disease, it exhibits some typical features of malignant tumors, such as proliferation, invasion, metastasis, and recurrence. Endometriosis is considered a chronic, inflammatory, and estrogen-dependent disease, and multiple factors contribute to its occurrence and development. In recent years, increasing attention has been given to the role of apoptosis in the pathogenesis of this disease. Some researchers believe that spontaneous apoptosis of the endometrium is critical in maintaining its normal structure and function, and abnormal apoptosis can promote the occurrence and development of endometriosis. Inflammation is another likely process in the pathogenesis of endometriosis. Inflammation mediates the adhesion, proliferation, differentiation, and invasion of ectopic lesions of endometriosis, primarily by regulating the function of immune cells and increasing the level of proinflammatory cytokines in body fluids. The ultimate initiators of apoptosis and inflammatory cell death (pyroptosis) are the caspase family proteases. In this article, we review the progress in recent years in caspase function as well as the possible role of these enzymes in the pathogenesis of endometriosis, indicating potential treatment strategies.

Multi-omics integration highlights the role of ubiquitination in endometriosis fibrosis

BACKGROUND

Endometriosis, characterized by the presence of active endometrial-like tissues outside the uterus, causes symptoms like dysmenorrhea and infertility due to the fibrosis of endometrial cells, which involves excessive deposition of extracellular matrix (ECM) proteins. Ubiquitination, an important post-transcriptional modification, regulates various biological processes in human diseases. However, its role in the fibrosis process in endometriosis remains unclear.

METHODS

We employed multi-omics approaches on two cohorts of endometriosis patients with 39 samples. GO terms and KEGG pathways enrichment analyses were used to investigate the functional changes involved in endometriosis. Pearson's correlation coefficient analysis was conducted to explore the relationship between global proteome and ubiquitylome in endometriosis. The protein expression levels of ubiquitin-, fibrosis-related proteins, and E3 ubiquitin-protein ligase TRIM33 were validated via Western blot. Transfecting human endometrial stroma cells (hESCs) with TRIM33 small interfering RNA (siRNA) in vitro to explore how TRIM33 affects fibrosis-related proteins.

RESULTS

Integration of proteomics and transcriptomics showed genes with concurrent change of both mRNA and protein level which involved in ECM production in ectopic endometria. Ubiquitylomics distinguished 1647 and 1698 ubiquitinated lysine sites in the ectopic (EC) group compared to the normal (NC) and eutopic (EU) groups, respectively. Further multi-omics integration highlighted the essential role of ubiquitination in key fibrosis regulators in endometriosis. Correlation analysis between proteome and ubiquitylome showed correlation coefficients of 0.32 and 0.36 for ubiquitinated fibrosis proteins in EC/NC and EC/EU groups, respectively, indicating positive regulation of fibrosis-related protein expression by ubiquitination in ectopic lesions. We identified ubiquitination in 41 pivotal proteins within the fibrosis-related pathway of endometriosis. Finally, the elevated expression of TGFBR1/α-SMA/FAP/FN1/Collagen1 proteins in EC tissues were validated across independent samples. More importantly, we demonstrated that both the mRNA and protein levels of TRIM33 were reduced in endometriotic tissues. Knockdown of TRIM33 promoted TGFBR1/p-SMAD2/α-SMA/FN1 protein expressions in hESCs but did not significantly affect Collagen1/FAP levels, suggesting its inhibitory effect on fibrosis in vitro.

CONCLUSIONS

This study, employing multi-omics approaches, provides novel insights into endometriosis ubiquitination profiles and reveals aberrant expression of the E3 ubiquitin ligase TRIM33 in endometriotic tissues, emphasizing their critical involvement in fibrosis pathogenesis and potential therapeutic targets.

Serum Levels of Interleukins in Endometriosis Patients: A Systematic Review and Meta-analysis

OBJECTIVE

The aims of this systematic review and meta-analysis were to produce a comprehensive survey of the serum levels of interleukins (ILs) in untreated people with endometriosis compared with people without endometriosis.

DATA SOURCES

A systematic literature search of English language studies within Cinahl, Medline Complete, PubMed, and Scopus from inception to May 2023 was performed.

METHODS OF STUDY SELECTION

We included studies that compared IL serum levels in people with endometriosis to those without endometriosis. Meta-analysis was performed on IL-1RA, IL-1β, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12, IL-17A, IL-18, IL-23, and IL-37.

TABULATION, INTEGRATION, AND RESULTS

The systematic search retrieved 651 studies, of which 77 underwent a full-text review. A total of 30 studies met inclusion criteria for the meta-analysis. IL-1Ra, IL-6, and IL-37 serum levels were 2.56 (95% CI 2.20-2.92, p <.001), 1.38 (95% CI 0.58-2.17, p <.001), and 1.77 (95% CI 1.33-2.20, p <.001) standard deviations higher in the patients with endometriosis compared with patients without endometriosis while IL-23 serum levels 0.40 (95% CI -0.73 to -0.07, p = .02) standard deviations lower, respectively.

CONCLUSION

There is mounting evidence that ILs, especially IL-6, may be good candidates for unique noninvasive diagnostic tools and/or treatment pathways for endometriosis.

Serum Metabolites as Diagnostic Biomarkers in Patients with Endometriosis

Endometriosis diagnosis is usually delayed. The gold standard for diagnosing endometriosis is laparoscopy, which is invasive and accompanied by several risks. Currently, there are no effective non-invasive biomarkers for diagnosing endometriosis. Here, we investigated whether metabolites whose levels are altered in patients with endometriosis hold potential as diagnostic biomarkers for the disease. This case-control study involved 32 patients with endometriosis and 29 patients with other benign gynecological disease. The diagnosis of all patients was confirmed through postoperative histopathological examination, and the patients were divided into two groups: an endometriosis group (EM) and a control group. Fasting blood was collected and used for non-targeted metabolomic-based detection. The data were processed through principal component analysis, orthogonal partial least squares discriminant analysis, and significance analysis of microarrays. A univariate receiver operating characteristic curve was used to evaluate the diagnostic value of the metabolites. The metabolite profiles of patients with endometriosis were markedly different compared with those of the controls. In addition, several metabolic pathways, including biosynthesis of unsaturated fatty acids, arginine biosynthesis, and glutathione metabolism, were altered. Ornithine and medorinone showed better potential as biomarkers for endometriosis diagnosis than CA125. We analyzed the altered metabolic profiles in patients with endometriosis and found ornithine and medorinone as potential non-invasive biomarkers for endometriosis diagnosis, whereas the combined ornithine-medorinone diagnosis is more valuable. These findings may help advance research on non-invasive diagnostic biomarkers for endometriosis. Further research with an improved study design and a larger cohort should be performed to confirm the diagnostic potential and clinical application of these biomarkers.

Establishment of a diagnostic model of endometriosis based on disulfidptosis-related genes

OBJECTIVES

We aimed to establish a diagnostic model of endometriosis (EM) based on disulfidptosis-related genes (DRGs).

MATERIALS AND METHODS

The mRNA expression data of EM were downloaded from the gene expression omnibus database and subjected to differential analysis, and co-expression analysis was performed based on 10 disulfidptosis genes to acquire DRGs. The differentially expressed DRGs were subjected to biofunctional analysis. Lasso analysis and support vector machine-recursive feature elimination (SVM-RFE) analysis were employed to extract the intersection of feature genes as biomarkers, and the diagnostic values of biomarkers for EM were evaluated based on receiver operating characteristic curves. The correlations between biomarkers and the immune microenvironment were assessed by Pearson analysis of biomarkers and immune cell infiltration levels.

RESULTS

Transforming growth factor β stimulated protein clone 22 domain family member 4 (TSC22D4), and F-box/SPRY domain-containing protein 1 (FBXO45) worked as the diagnostic classifiers in EM, with an obvious decrease in FBXO45 expression and an evident increase in TSC22D4 expression. The areas under the curves of FBXO45 and TSC22D4 were 0.752 and 0.706, respectively, and the area of FBXO45 combined with TSC22D4 reached 0.865, suggesting that TSC22D4 and FBXO45 had high predictive values. The diagnostic markers were closely correlated with immune cell infiltration.

CONCLUSION

The diagnostic markers constructed based on disulfidptosis are good predictors for EM, which have close correlations with EM.

Role of Molecular Biomarkers in Endometriosis-Related Infertility: A Narrative Review of the Literature

Endometriosis is a chronic benign inflammatory disease that affects women of reproductive age. The clinical presentations of endometriosis include dysmenorrhea, dyspareunia, chronic pelvic pain, and infertility. There is a well-established association between endometriosis and infertility. Therefore, there is a need for an early diagnosis of endometriosis-related infertility. In this study, we aim to identify the role of biomarkers as predictive factors of the presence of the disease and its severity and their correlation with the pregnancy outcome. We performed an electronic database search of all published studies in PubMed and EMBASE from January 2018 to May 2023. Numerous innovative biomarkers identified in cases of endometriosis and infertility have been studied over the past years, including micro-RNAs, BCL6 endometrial expression, cytotoxic T-lymphocyte antigen 4, human leukocyte antigen G, programmed cell death protein 1, programmed cell death ligand 1 immune checkpoint molecules, plasma fibronectin-fibrin complexes, homeobox A10 gene, systemic inflammatory response markers, uterine natural killer cells, and the eutopic endometrium proteome. Considerable research has been done to identify diagnostic biomarkers for the early detection and prevention of endometriosis-associated infertility. However, none of these biomarkers displayed enough diagnostic accuracy to be used in daily clinical practice. Future research is valuable to establish them as reliable diagnostic tools.

A Comprehensive Review of the Diagnostic Landscape of Endometriosis: Assessing Tools, Uncovering Strengths, and Acknowledging Limitations

Endometriosis is a prevalent yet often underdiagnosed condition characterized by the presence of endometrial-like tissue outside the uterus, leading to significant morbidity and impaired quality of life. A timely and accurate diagnosis of endometriosis is essential for effective management and improved patient outcomes. This review provides a comprehensive overview of the current diagnostic landscape of endometriosis, including clinical evaluation, imaging modalities, biomarkers, and laparoscopy. The strengths and limitations of each diagnostic approach are critically evaluated, alongside challenges such as delayed diagnosis and misinterpretation of findings. The review emphasizes the importance of multidisciplinary collaboration, standardized diagnostic protocols, and ongoing research to enhance diagnostic accuracy and facilitate early intervention. By addressing these challenges and leveraging emerging technologies, healthcare professionals can improve the diagnosis and management of endometriosis, ultimately enhancing the well-being of affected individuals.

Angiogenesis signaling in endometriosis: Molecules, diagnosis and treatment (Review)

Endometriosis (EM) is one of the most common diseases among women of reproductive age. The etiology and pathogenesis of EM remain unclear and therefore there is a lack of effective treatment measures, which affects physical and mental health, as well as the quality of life of patients with EM. Angiogenesis has become a hotspot for research on the pathogenesis of EM; the role of angiogenesis‑related serological markers and anti‑angiogenic therapy in the diagnosis and treatment of EM is promising for early diagnosis and treatment of EM. Angiogenesis in EM is subject to complex regulation by hormones, immunity and associated cytokines. Therefore, novel targets for angiogenesis therapy are also being discovered and developed. The present review summarized the pathological mechanisms of angiogenesis and the value of relevant markers in pathogenesis and diagnosis of EM, along with the status of research on anti‑angiogenic drugs in the treatment of EM. The role of angiogenesis in EM provides an important reference for treatment and diagnosis, but there is no uniform non‑invasive diagnostic marker and proven strategy for anti‑angiogenesis.

Regulatory mechanism of GPER in the invasion and migration of ectopic endometrial stromal cells in endometriosis

Endometriosis (EMS) is a chronic inflammatory disorder of high incidence that causes serious reproductive consequences. High estrogen production is a consistently observed endocrine feature of EMS. The present study aims to probe the molecular mechanism of G protein-coupled estrogen receptor 1 (GPER) in the invasion and migration of ectopic endometrial stromal cells (Ect-ESCs) and provides a new rationale for EMS treatment. Eutopic and ectopic endometrial tissues were collected from 41 EMS patients, and primary ESCs were separated. GPER, miR-16-5p, and miR-103a-3p levels in cells and tissues were determined by qRT-PCR or Western blot assay. Cell viability, proliferation, invasion, and migration were evaluated by CCK-8, colony formation, and Transwell assays. The upstream miRNAs of GPER were predicted by databases, and dual-luciferase assay was performed to validate the binding of miR-16-5p and miR-103a-3p to GPER 3'UTR. GPER was highly expressed in EMS tissues and Ect-ESCs. Inhibition of GPER mitigated the proliferation, invasion, and migration of Ect-ESCs. GPER was regulated by miR-16-5p and miR-103a-3p. Overexpression of miR-16-5p and miR-103a-3p negatively regulated GPER expression and inhibited the invasion and migration of Ect-ESC. In conclusion, GPER promoted the invasion and migration of Ect-ESCs, which can be reversed by upstream miR-16-5p and miR-103a-3p.

Brain-derived neurotrophic factor (BDNF) as a potential marker of endometriosis: a systematic review and meta-analysis

BACKGROUND

The existing literature on the association between BDNF protein levels and endometriosis presents inconsistent findings. This systematic review and meta-analysis aim to synthesize the available evidence and evaluate the possible relationship between BDNF protein levels and endometriosis.

METHODS

Electronic databases (PubMed, Embase, Scopus, PsycINFO, and Web of Science) were used to conduct a comprehensive literature search from inception to June 2023. The search strategy included relevant keywords and medical subject headings (MeSH) terms related to BDNF, endometriosis, and protein levels. A random-effects model was used for the meta-analysis, and to explore heterogeneity subgroup analyses were performed. funnel plots and statistical tests were used for assessing the publication bias.

RESULTS

A total of 12 studies were included. The pooled standardized mean difference (SMD) of BDNF levels between women with endometriosis and controls was 0.87 (95% confidence interval [CI] 0.34 to 1.39, p = 0.001; I2 = 93%). The results showed that blood levels of BDNF are significantly higher in endometriosis patients (SMD: 1.13 95% CI 0.54 to 1.73, p = 0.0002; I2 = 93%). No significant publication bias was observed based on the results of Egger's regression test ((p = 0.15).

CONCLUSION

This study revealed a significant difference between patients diagnosed with endometriosis and healthy control in the level of BDNF. The results indicate that women with endometriosis have higher levels of BDNF. Further studies are needed to be undertaken to investigate the role of BDNF in endometriosis pathophysiology and the diagnostic value of BDNF in endometriosis.

Chronic Pelvic Puzzle: Navigating Deep Endometriosis with Renal Complications

This case report delves into the intricacies of a challenging clinical scenario involving deep pelvic endometriosis, which manifested with renal complications. Endometriosis, a complex gynecological condition, is explored in this case, highlighting its multifaceted nature. The patient presented with a complex interplay of symptoms, including chronic pelvic pain, urinary tract issues, and severe deep adenomyosis. The diagnostic journey was protracted, emphasizing the need for early recognition and intervention in such cases. A thorough evaluation, including laparoscopic examination and histopathological analysis, revealed the extensive presence of endometriotic lesions in various pelvic and renal structures, ultimately leading to left hydronephrosis. The report underscores the significance of timely diagnosis and surgical intervention to prevent irreversible renal damage. This case provides valuable insights into the management of deep endometriosis with renal involvement and the importance of interdisciplinary collaboration. Understanding the complexities of this condition can aid in improving patient outcomes and enhancing the quality of care provided.

Machine learning algorithms for a novel cuproptosis-related gene signature of diagnostic and immune infiltration in endometriosis

Endometriosis (EMT) is an aggressive disease of the reproductive system, also called "benign cancer". However, effective treatments for EMT are still lacking in clinical practice. Interestingly, immune infiltration is significantly involved in EMT pathogenesis. Currently, no studies have shown the involvement of cuproptosis-related genes (CRGs) in regulating immune infiltration in EMT. This study identified three CRGs such as GLS, NFE2L2, and PDHA1, associated with EMT using machine learning algorithms. These three CRGs were upregulated in the endometrium of patients with moderate/severe EMT and downregulated in patients with infertility. Single sample genomic enrichment analysis (ssGSEA) revealed that these CRGs were closely correlated with autoimmune diseases such as systemic lupus erythematosus. Furthermore, these CRGs were correlated with immune cells such as eosinophils, natural killer cells, and macrophages. Therefore, profiling patients based on these genes aid in a more accurate diagnosis of EMT progression. The mRNA and protein expression levels of GLS, NFE2L2 and PDHA1 were validated by qRT-PCR and WB studies in EMT samples. These findings provide a new idea for the pathology and treatment of endometriosis, suggesting that CRGs such as GLS, NFE2L2 and PDHA1 may play a key role in the occurrence and development of endometriosis.

Evaluation of new biomarkers in stage III and IV endometriosis

OBJECTIVE

To investigate the efficacy of new endometriosis biomarkers in diagnosis and treatment.

METHODS

Thirty women with Stage III-IV endometriosis who were given an indication for surgery and 49 control patients were compared. Preoperative and postoperative serum levels of Annexin A5 (ANXA5), soluble intercellular adhesion molecule-1 (sICAM-1), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), soluble vascular cell adhesion molecule-1 (sVCAM-1), vascular endothelial growth factors (VEGF) and Ca-125 measurements were compared.

RESULTS

AUCs of ANXA5, sICAM-1, IL-6, TNF-α, VCAM-1, VEGF biomarkers were not found to be significant in diagnosing endometriosis when evaluated alone (p > 0.05). Only the AUC of the Ca-125 biomarker values were found to be significant with 73% sensitivity and 98% specificity (p < 0.001). However, when Ca-125 and ANXA5 were evaluated together, it was concluded that the diagnosis of endometriosis could be made with 73% sensitivity and 100% specificity.

CONCLUSION

When Ca-125 and ANXA5 are evaluated together, it seems to be more valuable than Ca-125 alone in diagnosing endometriosis.

MicroRNAs in Endometriosis: Insights into Inflammation and Progesterone Resistance

Endometriosis, a non-malignant gynecological disorder influenced by estrogen, involves the growth of endometrial tissue outside the uterus. Its development includes processes such as inflammation, progesterone resistance, angiogenesis, and cell proliferation. Epigenetic factors, particularly the dysregulation of microRNAs (miRNAs), have emerged as key factors in these mechanisms in endometriosis. This review aims to unveil the intricate molecular processes that control inflammation, progesterone resistance, and miRNA functions in endometriosis. In addition, it provides a comprehensive overview of the current understanding regarding the involvement of miRNAs in the inflammatory aspects of this condition. This synthesis encompasses research investigating the molecular underpinnings of inflammation, along with the biogenesis and roles of miRNAs in endometriosis. Furthermore, it examines human studies and functional analyses to establish the intricate connection between miRNAs, inflammation, and progesterone resistance in the context of endometriosis. The results highlight the significant impact of dysregulated miRNAs on the inflammatory pathways and hormonal imbalances characteristic of endometriosis. Consequently, miRNAs hold promise as potential non-invasive biomarkers and targeted therapeutic agents aimed at addressing inflammation and enhancing the response to progesterone treatment in individuals with endometriosis.

'It just stops me from living': A qualitative study of losses experienced by women with self-reported endometriosis

AIMS

To understand the experience of loss in Australian women with endometriosis.

DESIGN

A total of 532 participants completed an online survey containing three open-ended questions relating to pelvic pain and activity loss due to endometriosis. Participants were Australian women aged between 18 and 50 years (M = 30.8, SD = 7.1) with a self-reported diagnosis of endometriosis. An inductive, qualitative approach, with template analysis was used to identify and organize themes. A pragmatic feminist perspective was used to interpret the findings.

RESULTS

Three main themes were identified: the loss of liberty: 'I'm trapped in the house'; the loss of bodily autonomy: 'I can barely move/breathe/talk' and loss of connection: 'It stops me from being social'. Pain emerged as the greatest concern for participants, preventing them from the physical functioning required to participate in many of life's activities.

CONCLUSIONS

The losses women with endometriosis experience are wide-reaching, restricting control and choice across multiple life domains. Losses were often unacknowledged by loved ones and healthcare providers, further impacting the physical, emotional and mental health of participants.

PATIENT OR PUBLIC CONTRIBUTION

People with endometriosis were involved in the design of the study, including identifying topics of interest.

Serum HSF1 is upregulated in endometriosis patients and serves as a potential diagnostic biomarker

Endometriosis (EMS) is a prevalent gynecological condition lacking reliable diagnostic biomarkers. This prospective study aimed to analyze the potential of serum heat shock transcription factor 1 (HSF1) as a diagnostic marker for EMS. Clinical features of 92 EMS patients and 52 controls were recorded, revealing significant differences in dysmenorrhea, dyspareunia, pelvic pain, nulliparity, and CA125 levels. Serum HSF1 was upregulated in EMS patients, with higher levels in American Society for Reproductive Medicine (ASRM) III/IV than ASRM I/II. Receiver operating characteristic curve analysis demonstrated good diagnostic function for serum HSF1 (AUC: 0.857, sensitivity: 91.30%, specificity: 63.46%). Serum HSF1, dysmenorrhea, dyspareunia, and nulliparity were independent risk factors for EMS, while dysmenorrhea and serum HSF1 were independent risk factors for EMS severity. Additionally, the GSE25628 dataset was downloaded from the GEO database for differential analysis of gene expression. The HSF1 downstream target genes PTGES3, HSP90AA1, and HSPB1 showed significant differential expression in EMS, suggesting their involvement in the regulatory mechanism of HSF1 in EMS.

Expression of HOXA10 Gene in Women with Endometriosis: A Systematic Review

The homeobox A10 (HOXA10) gene is known to be related to endometriosis; however, due to a lack of knowledge/evidence in the pathogenesis of endometriosis, the mechanisms that link HOXA10 to endometriosis still need to be clarified. This review addresses the difference in the expression of the HOXA10 gene in endometriotic women versus non-endometriotic women across populations by country and discusses its influences on women's fertility. An organized search of electronic databases was conducted in Scopus, ScienceDirect, PubMed, and Web of Science. The keywords used were (HOXA10 OR "homeobox A10" OR PL OR HOX1 OR HOX1H OR HOX1.8) AND ("gene expression") AND (endometriosis). The initial search resulted in 623 articles, 10 of which were included in this review. All ten papers included in this study were rated fair in terms of the quality of the studies conducted. The expression of the HOXA10 gene was found to be downregulated in most studies. However, one study provided evidence of the downregulation and upregulation of HOXA10 gene expression due to the localization of endometriotic lesions. Measuring the expression of the HOXA10 gene in women is clinically essential to predicting endometriosis, endometrial receptivity, and the development of pinopodes in the endometrium during the luteal phase.

Use of the Free Endometriosis Risk Advisor App as a Non-Invasive Screening Test for Endometriosis in Patients with Chronic Pelvic Pain and/or Unexplained Infertility

Endometriosis is a prevalent condition that affects millions of individuals globally, leading to various symptoms and significant disruptions to their quality of life. However, the diagnosis of endometriosis often encounters delays, emphasizing the pressing need for non-invasive screening. This retrospective cross-sectional study aimed to evaluate the utility of the Endometriosis Risk Advisor (EndoRA) mobile application in screening for endometriosis in patients with chronic pelvic pain and/or unexplained infertility. The study consisted of 293 patients who met specific criteria: they were English-speaking individuals with chronic pelvic pain and/or unexplained infertility, owned smartphones, and had no prior diagnosis of endometriosis. The results demonstrated that the EndoRA score exhibited a high sensitivity of 93.1% but a low specificity of 5.9% in detecting endometriosis. The positive predictive value was 94.1%, while the negative predictive value was 5.0%. Although the study had limitations and potential selection bias, its findings suggest that EndoRA can serve as a valuable screening tool for high-risk individuals, enabling them to identify themselves as being at an increased risk for endometriosis. EndoRA's non-invasive nature, free access, and easy accessibility have the potential to streamline evaluation and treatment processes, thereby empowering individuals to seek timely care and ultimately improving patient outcomes and overall well-being.

TGFBI as a candidate biomarker for non-invasive diagnosis of early-stage endometriosis

STUDY QUESTION

Can cartilage oligomeric matrix protein (COMP) and transforming growth factor-β-induced protein ig-h3 (TGFBI) alone or in combination with cancer antigen 125 (CA-125) be considered as potential blood biomarkers of endometriosis?

SUMMARY ANSWER

The results of this study indicate that COMP has no diagnostic value. TGFBI has potential as a non-invasive biomarker of the early stages of endometriosis, while TGFBI together with CA-125 has similar diagnostic characteristics as CA-125 alone for all stages of endometriosis.

WHAT IS KNOWN ALREADY

Endometriosis is a common, chronic gynecological disease that significantly affects patient quality of life by causing pain and infertility. The gold standard for diagnosis is visual inspection of pelvic organs by laparoscopy, therefore there is an urgent need for discovery of non-invasive biomarkers for endometriosis to reduce diagnostic delays and allow earlier treatment of patients. The potential biomarkers for endometriosis evaluated in this study (COMP and TGFBI) were previously identified by our proteomic analysis of peritoneal fluid samples.

STUDY DESIGN, SIZE, DURATION

This is a case-control study divided into a discovery (n = 56 patients) and a validation phase (n = 237 patients). All patients were treated between 2008 and 2019 in a tertiary medical center.

PARTICIPANTS/MATERIALS, SETTING, METHOD

Patients were stratified based on the laparoscopic findings. The discovery phase included 32 endometriosis patients (cases) and 24 patients with confirmed absence of endometriosis (controls). The validation phase included 166 endometriosis and 71 control patients. Concentrations of COMP and TGFBI were measured by ELISA in plasma samples, whereas concentration of CA-125 was measured using a clinically validated assay for serum samples. Statistical and receiver operating characteristic (ROC) curve analyses were performed. The classification models were built using the linear support vector machine (SVM) method with the SVM built-in feature ranking method.

MAIN RESULTS AND THE ROLE OF CHANCE

The discovery phase revealed significantly increased concentration of TGFBI, but not COMP, in plasma samples of patients with endometriosis compared to controls. In this smaller cohort, univariate ROC analysis showed fair diagnostic potential of TGFBI, with an AUC value of 0.77, sensitivity of 58%, and specificity of 84%. The classification model built using linear SVM and combining TGFBI and CA-125 showed an AUC value of 0.91, sensitivity of 88% and specificity of 75% in distinguishing patients with endometriosis from controls. The validation phase results revealed similar diagnostic characteristics of the SVM model combining TGFBI and CA-125, with an AUC value of 0.83, sensitivity of 83% and specificity of 67% and CA-125 alone with AUC value of 0.83, sensitivity of 73% and specificity of 80%. TGFBI exhibited good diagnostic potential for early-stage endometriosis (revised American Society for Reproductive Medicine stage I-II), with an AUC value of 0.74, sensitivity of 61% and specificity of 83% compared to CA-125, which had an AUC value of 0.63, sensitivity of 60% and specificity of 67%. An SVM model combining TGFBI and CA-125 showed a high AUC value of 0.94 and sensitivity of 95% for diagnosing moderate-to-severe endometriosis.

LIMITATIONS, REASONS FOR CAUTION

The diagnostic models were built and validated from a single endometriosis center, and thus further validation and technical verification in a multicenter study with a larger cohort is needed. Additional limitation was lack of histological confirmation of disease for some patients in the validation phase.

WIDER IMPLICATIONS OF THE FINDINGS

This study revealed for the first time increased concentration of TGFBI in plasma samples of patients with endometriosis, particularly those with minimal-to-mild endometriosis, compared to controls. This is the first step in considering TGFBI as a potential non-invasive biomarker for the early stages of endometriosis. It also opens a path for new basic research to investigate the importance of TGFBI in the pathophysiology of endometriosis. Further studies are needed to confirm the diagnostic potential of a model based on TGFBI and CA-125 for the non-invasive diagnosis of endometriosis.

STUDY FUNDING/COMPETING INTEREST(S)

The preparation of this manuscript was supported by grant J3-1755 from the Slovenian Research Agency to T.L.R and EU H2020-MSCA-RISE project TRENDO (grant 101008193). All authors declare that they have no conflicts of interest.

TRIAL REGISTRATION NUMBER

NCT0459154.

Current endometriosis care and opportunities for improvement

Endometriosis is a chronic disease associated with debilitating pain that affects many people assigned female at birth, from menarche through menopause, not just causing pain and infertility, but also negatively impacting quality of life, participation in daily activities, productivity and income. It is associated with increased incidence of obstetric and neonatal complications, depression, other chronic diseases, and substantial healthcare costs. Despite the profound negative impact of endometriosis on quality of life, current treatment options remain sub-optimal and many patients express dissatisfaction with current care. The prevailing acute-care, single-provider model in which the provider works in relative isolation and thus with limited therapeutic strategies readily available, proves inadequate for treating endometriosis. Patients would benefit from earlier diagnosis and referral to a center capable of providing a comprehensive and multi-modal management plan that utilizes a chronic care model. Often this can only be achieved through multidisciplinary teams of providers with expertise in endometriosis. Researchers need to agree on standardized core outcome measures, relevant to patients with endometriosis and the healthcare system as a whole. Only through increased education and recognition of endometriosis as a chronic disease can we achieve better treatment outcomes.

How Do Microorganisms Influence the Development of Endometriosis? Participation of Genital, Intestinal and Oral Microbiota in Metabolic Regulation and Immunopathogenesis of Endometriosis

Microorganisms inhabiting the human body play an extremely key role in its proper functioning, as well as in the development of the immune system, which, by maintaining the immune balance, allows you to enjoy health. Dysbiosis of the intestinal microbiota, or in the oral cavity or reproductive tract, understood as a change in the number and diversity of all microorganisms inhabiting them, may correlate with the development of many diseases, including endometriosis, as researchers have emphasized. Endometriosis is an inflammatory, estrogen-dependent gynecological condition defined by the growth of endometrial cells outside the uterine cavity. Deregulation of immune homeostasis resulting from microbiological disorders may generate chronic inflammation, thus creating an environment conducive to the increased adhesion and angiogenesis involved in the development of endometriosis. In addition, research in recent years has implicated bacterial contamination and immune activation, reduced gastrointestinal function by cytokines, altered estrogen metabolism and signaling, and abnormal progenitor and stem cell homeostasis, in the pathogenesis of endometriosis. The aim of this review was to present the influence of intestinal, oral and genital microbiota dysbiosis in the metabolic regulation and immunopathogenesis of endometriosis.

Endometriosis Treatment: Role of Natural Polyphenols as Anti-Inflammatory Agents

Endometriosis is an estrogen-dependent common chronic inflammatory disease defined by the presence of extrauterine endometrial tissue that promotes pelvic pain and fertility impairment. Its etiology is complex and multifactorial, and several not completely understood theories have been proposed to describe its pathogenesis. Indeed, this disease affects women's quality of life and their reproductive system. Conventional therapies for endometriosis treatment primarily focus on surgical resection, lowering systemic levels of estrogen, and treatment with non-steroidal anti-inflammatory drugs to counteract the inflammatory response. However, although these strategies have shown to be effective, they also show considerable side effects. Therefore, there is a growing interest in the use of herbal medicine for the treatment of endometriosis; however, to date, only very limited literature is present on this topic. Polyphenols display important anti-endometriotic properties; in particular, they are potent phytoestrogens that in parallel modulates estrogen activity and exerts anti-inflammatory activity. The aim of this review is to provide an overview on anti-inflammatory activity of polyphenols in the treatment of endometriosis.

Diagnosis and management of small bowel obstruction in the ileum caused by endometriosis: A case report

Small bowel obstruction is a rare complication of endometriosis, a condition defined by the presence of endometrial tissue outside of the uterine cavity. The rectosigmoid junction is the most common site for intestinal endometriosis. However, small bowel involvement, particularly of the ileum, is less common, and is a much rarer location for endometriosis causing bowel obstruction. A 37-year-old woman with a medical history of endometriosis requiring multiple abdominal surgeries presented with signs and symptoms of small bowel obstruction. Computerized tomography indicated a transition point at the terminal ileum. Conservative treatment did not alleviate her symptoms, and so a right hemicolectomy was performed to relieve her obstruction. Endometriosis of the ileum was discovered on intraoperative pathology. The diagnosis of endometriosis and treatment options, especially as they relate to imaging techniques, are currently limited. There is a need for an improvement in the diagnosis of endometriosis. Advanced imaging techniques may lead to a more patient-centered approach to treatment in cases of small bowel obstruction. Prior to obstruction, serial imaging might catch the proliferation of endometrial tissue into the bowel. Conservative treatment might be tailored to endometriosis to help relieve obstruction and in surgical management resection margins might be adjusted to help preserve the bowel. This would improve patient quality of life by improving treatment.

A Case Report on Endometriosis: "A Tip of Iceberg" Disease Identified and Managed Better With Imaging

Endometriosis has been more common in recent decades as a result of improved diagnosis supported by enhanced clinical concepts and greater imaging tools. A multidisciplinary care strategy that extends beyond the cellular level is required for this complicated pathophysiological condition to enable patients to live disease-free lives. This case study features a young woman who was diagnosed with endometriosis and was anxious about future fertility. The condition eventually led to a series of events that defined the intricacy of the sickness involved and the accompanying complications that were better detected, and so, therapy was comparatively simplified by imaging, which helped manage the ailment and its issues. The related complications are well established; however, with the impending use of 3D imaging technology, the disease, its extent, and associated complications can be managed in a well-planned manner.

Endometriosis and the Temporomandibular Joint-Preliminary Observations

(1) Background: The complete picture of the disease is not fully recognized and extends far beyond the pelvis. The disease's impacts lead to systemic inflammation, in turn resulting in sensitization to pain. The aim of this study was to check whether statistical correlations exist in women with endometriosis with regard to their experience of pain: headache, pelvic pain, temporomandibular joint pain, along with teeth clenching and the treatment of the disease. We constructed contingency tables, followed by Pearson's chi-square test and Cramer's V coefficient values. (2) Methods: A survey was conducted among 128 women aged 33.43 ± 5.79 with a diagnosis of endometriosis (disease duration 6.40 ± 5.88 years). (3) Results: There was a correlation between the occurrence of pain on the right and left sides of the pelvis and pain on the right and left sides of the temporomandibular joint, p-value = 0.0397, V = 0.2350, and between the presence of pelvic pain and the treatment of endometriosis, p-value = 0.0104, V = 0.3709, and between the presence of pain outside the pelvis and the treatment of endometriosis, p-value = 0.0311, V = 0.4549. There was a highly significant correlation between teeth clenching and temporomandibular joint pain, p-value = 0.0005, V = 0.3695. (4) Conclusions: The study revealed a correlation between pelvic endometriosis symptoms and symptoms in the temporomandibular joint.

The DNA demethylation-regulated SFRP2 dictates the progression of endometriosis via activation of the Wnt/β-catenin signaling pathway

Background

Endometriosis cause decreases in life quality and pelvic pain in reproductive-age women. Methylation abnormalities played a functional role in the progression of endometriosis, this study aimed to explore the mechanisms mediated by abnormal methylation in the development of EMS.

Materials and methods

Next-generation sequencing dataset and methylation profiling dataset were used to screen out the key gene SFRP2. Western bolt, Real-time PCR, Aza-2?deoxycytidine treatment, luciferase reporter assay, Methylation-specific PCR , Bisulfite sequencing PCR and lentivirus infection were carried out to detect the methylation status and signaling pathway with the primary epithelial cells. Transwell assay and wound scratch assay were implemented to observe the differences of migration ability with the intervening with the expression of SFRP2.

Results

To define the role of the DNA methylation-regulated genes in the pathogenesis of EMS, we performed both DNA methylomic and expression analyses of ectopic endometrium and ectopic endometrium epithelial cells(EEECs) and found that SFRP2 is demethylated/upregulated in ectopic endometrium and EEECs. The expression of lentivirus carrying SFRP2 cDNA up-regulates the activity of Wnt signaling and the protein expression of ?-catenin in EEECs. SFRP2 impact on the invasion and migration of ectopic endometrium by modulating the activities of the Wnt/?-catenin signaling pathway. The invasion and migration ability of EEECs were significantly strengthened after demethylation treatment including 5-Aza and the knockdown of DNMT1.

Conclusion

In summary, the increased SFRP2 expression-induced Wnt/?-catenin signaling due to the demethylation of the SFRP2 promoter plays an important role in the pathogenesis of EMS, suggesting that SFRP2 might be a therapeutic target for EMS treatment.

Phage vs. Phage: Direct Selections of Sandwich Binding Pairs

The sandwich format immunoassay is generally more sensitive and specific than more common assay formats, including direct, indirect, or competitive. A sandwich assay, however, requires two receptors to bind non-competitively to the target analyte. Typically, pairs of antibodies (Abs) or antibody fragments (Fabs) that are capable of forming a sandwiching with the target are identified through a slow, guess-and-check method with panels of candidate binding partners. Additionally, sandwich assays that are reliant on commercial antibodies can suffer from changes to reagent quality outside the researchers' control. This report presents a reimagined and simplified phage display selection protocol that directly identifies sandwich binding peptides and Fabs. The approach yielded two sandwich pairs, one peptide-peptide and one Fab-peptide sandwich for the cancer and Parkinson's disease biomarker DJ-1. Requiring just a few weeks to identify, the sandwich pairs delivered apparent affinity that is comparable to other commercial peptide and antibody sandwiches. The results reported here could expand the availability of sandwich binding partners for a wide range of clinical biomarker assays.

Proteins in urine - Possible biomarkers of endometriosis

In the pathogenesis of endometriosis, a number of pathological reactions occur. Proteins secreted in the urine are thought to interact with each other and stimulate the pathological processes in endometriosis. Identifying one or more proteins that are specific enough and could serve as biomarkers for endometriosis is both a challenge and a necessity that would facilitate diagnosis. The urine of patients treated in a tertiary university hospital between July 1, 2020 and June 30, 2021 was analyzed. The studied group consists of patients who were treated surgically for endometriosis and in whom the diagnosis was confirmed by pathohistological analysis. The control group consists of patients who were operated for functional ovarian cysts. Urinary proteins were analyzed by chromatography and mass spectrometry (LC-MS/MS). We identified 17 proteins in urine whose concentrations were statistically significantly different in the group with endometriosis (N = 16) compared with the control groups (N = 16). The detected proteins were classified into groups according to their function in invasion, migration and proliferation, proteolysis, immune system, cell adhesion and vascular system. For all mentioned proteins the difference in concentration is statistically significant p < 0.005. Proteins are secreted in the urine of patients with endometriosis that may be involved in the pathogenesis of the disease and are possible biomarkers for endometriosis.

Oxidative Stress as a Potential Underlying Cause of Minimal and Mild Endometriosis-Related Infertility

Oxidative stress (OS) plays an important role in a variety of physiological and pathological processes of the female reproductive system. In recent years the relationship between OS and endometriosis has been of particular interest, and a theory has been suggested that OS may be a cause of endometriosis development. While the link between endometriosis and infertility is well established, minimal or mild stages of endometriosis are not considered to cause infertility. Increasing evidence of OS as a leading agent in the development of endometriosis has brought up a theory of minimal/mild endometriosis itself being one of the manifestations of high OS rather than a separate disease which directly causes infertility. Moreover, further development of the disease is thought to contribute to an increased production of reactive oxygen species (ROS) thus leading to the progression of endometriosis itself as well as to other pathological processes in the female reproductive system. Therefore, in case of minimal or mild endometriosis, the less invasive treatment could be offered in order to stop the ongoing cycle of endometriosis-reinforced excess ROS production and to reduce their harmful effects. In this article the existing connection between OS, endometriosis, and infertility is explored.

Autoantibody screening of plasma and peritoneal fluid of patients with endometriosis

STUDY QUESTION

Are there specific autoantibody profiles in patients with endometriosis that are different from those in controls?

SUMMARY ANSWER

This study did not reveal a significantly higher prevalence of autoantibodies in the studied groups of patients.

WHAT IS KNOWN ALREADY

Various inflammatory factors are postulated to be involved in the pathomechanisms of endometriosis, and a potential link exists with autoimmune diseases, which may also play an important role. As the diagnosis of endometriosis remains invasive, it can only be confirmed using laparoscopy with histopathological examination of tissues. Numerous studies have focused on identifying useful biomarkers to confirm the disease, but without unequivocal effects. Autoantibodies are promising molecules that serve as potential prognostic factors.

STUDY DESIGN, SIZE, DURATION

A multicentre, cross-sectional study was conducted over 18 months (between 2018 and 2019), at eight Departments of Obstetrics and Gynaecology in several cities across Poland on 137 patients undergoing laparoscopic examination for the diagnosis of endometriosis.

PARTICIPANTS/MATERIALS, SETTINGS, METHODS

During laparoscopy, we obtained plasma samples from 137 patients and peritoneal fluid (PF) samples from 98 patients. Patients with autoimmune diseases were excluded from the study. Autoantibody profiling was performed using HuProt v3.1 human proteome microarrays.

MAIN RESULTS AND THE ROLE OF CHANCE

We observed no significant differences in the expression of autoantibodies in the plasma or PF between the endometriosis and control groups. The study revealed that in the PF of women with Stage II endometriosis, compared with other stages, there were significantly higher reactivity signals for ANAPC15 and GABPB1 (adj. P < 0.016 and adj. P < 0.026, respectively; logFC > 1 in both cases). Comparison of the luteal and follicular phases in endometriosis patients revealed that levels of NEIL1 (adj. P < 0.029), MAGEB4 (adj. P < 0.029), and TNIP2 (adj. P < 0.042) autoantibody signals were significantly higher in the luteal phase than in the follicular phase in PF samples of patients with endometriosis. No differences were observed between the two phases of the cycle in plasma or between women with endometriosis and controls. Clustering of PF and plasma samples did not reveal unique autoantibody profiles for endometriosis; however, comparison of PF and plasma in the same patient showed a high degree of concordance.

LIMITATIONS, REASONS FOR CAUTION

Although this study was performed using the highest-throughput protein array available, it does not cover the entire human proteome and cannot be used to study potentially promising post-translational modifications. Autoantibody levels depend on numerous factors, such as infections; therefore the autoantibody tests should be repeated for more objective results.

WIDER IMPLICATIONS OF THE FINDINGS

Although endometriosis has been linked to different autoimmune diseases, it is unlikely that autoimmune responses mediated by specific autoantibodies play a pivotal role in the pathogenesis of this inflammatory disease. Our study shows that in searching for biomarkers of endometriosis, it may be more efficient to use higher-throughput proteomic microarrays, which may allow the detection of potentially new biomarkers. Only research on such a scale, and possibly with different technologies, can help discover biomarkers that will change the method of endometriosis diagnosis.

STUDY FUNDING/COMPETING INTEREST(S)

This study was funded by a grant from the Polish Ministry of Health (grant no. 6/6/4/1/NPZ/2017/1210/1352). It was also funded by the Estonian Research Council (grant PRG1076) and the Horizon 2020 Innovation Grant (ERIN; grant no. EU952516), Enterprise Estonia (grant no. EU48695), and MSCA-RISE-2020 project TRENDO (grant no. 101008193). The authors declare that there is no conflict of interest.

TRIAL REGISTRATION NUMBER

N/A.

Current Role of Modern Chromatography with Mass Spectrometry and Nuclear Magnetic Resonance Spectroscopy in the Investigation of Biomarkers of Endometriosis

Endometriosis has a wide range of clinical manifestations, and the disease course is unpredictable, making the diagnosis a challenging task. Despite significant advances in the pathophysiology of endometriosis and various proposed theories, the exact etiology is not fully understood and is still unknown. The most commonly used biomarker of endometriosis is CA-125, however, it is nonspecific and is applied for cancers diagnosis. Therefore, the development of reliable noninvasive diagnostic tests for the early diagnosis of endometriosis remains one of the top priorities. Omics technologies are very promising approaches for constructing diagnostic models and biomarker discovery. Their use can greatly facilitate the study of such a complex disease as endometriosis. Nowadays, powerful analytical platforms commonly used in omics, such as gas and liquid chromatography with mass spectrometry and nuclear magnetic resonance (NMR) spectroscopy, have proven to be a promising tools for biomarker discovery. The aim of this review is to summarize the various features of the analytical approaches, practical challenges and features of gas and liquid chromatography with MS and NMR spectroscopy (including sample processing protocols, technological advancements, and methodology) used for profiling of metabolites, lipids, peptides and proteins in physiological fluids and tissues from patients with endometriosis. In addition, this report devotes special attention to the issue of how comprehensive analyses of these profiles can effectively contribute to the study of endometriosis. The search query included reports published between 2012 and 2022 years in PubMed, Web-of-Science, SCOPUS, Science Direct.

Non-invasive diagnosis of endometriosis: Immunologic and genetic markers

Endometriosis, a benign gynecologic and chronic inflammatory disease, is defined by the presence of endometrial tissue outside the uterus characterized mainly by pelvic pain and infertility. Because endometriosis affects approximately 10% of females, it represents a significant socioeconomic burden worldwide having tremendous impact on daily quality of life. Accurate and prompt diagnosis is crucial for the management of this debilitating disorder. Unfortunately, diagnosis is typically delayed to lack of specific symptoms and readily accessible biomarkers. Although histopathologic examination remains the current gold standard, this approach is highly invasive and not applicable for early screening. Recent work has focused on the identification of reliable biomarkers including immunologic, ie, immune cells, antibodies and cytokines, as well as genetic and biochemical markers, ie, microRNAs, lncRNAs, circulating and mitochondrial nucleic acids, along with some hormones, glycoproteins and signaling molecules. Confirmatory research studies are, however, needed to more fully establish these markers in the diagnosis, progression and staging of these endometrial lesions.

miR-424-5p combined with miR-17-5p has high diagnostic efficacy for endometriosis

PURPOSE

Endometriosis (EMT) is a chronic benign disease with high prevalence. This study investigated the diagnostic value of serum miR-17-5p, miR-424-5p, and their combined expressions for EMT.

METHODS

Total 80 EMT patients of reproductive age who underwent laparoscopy or laparotomy and were confirmed by pathological examination were included as the study subjects, and another 80 healthy women of reproductive age receiving gynecological examination and ultrasonography with no pelvic abnormalities were selected as the control group. The whole blood samples of enrolled subjects were collected and clinical characteristics were recorded. The miR-17-5p, miR-424-5p, VEGFA, IL-4, and IL-6 levels in the serum were measured. ROC curve was used to evaluate the diagnostic efficacy of miR-17-5p and miR-424-5p expressions for EMT. Pearson correlation was performed to analyze the correlation of miR-17-5p and miR-424-5p with clinical indexes in EMT patients.

RESULTS

miR-17-5p and miR-424-5p were downregulated in EMT patients. For diagnosing EMT, the AUC of miR-17-5p was 0.865 and cutoff value was 0.890 (91.3% sensitivity and 85% specificity), the AUC of miR-424-5p was 0.737, and cutoff value was 0.915 (98.8% sensitivity and 61.2% specificity), and the AUC of miR-424-5p combined with miR-17-5p was 0.938 and cutoff value was 2.205 (93.8% sensitivity and 88.7% specificity), with the diagnostic efficacy higher than miR-424-5p or miR-17-5p alone. miR-17-5p and miR-424-5p expressions were negatively correlated with dysmenorrhea, infertility, pelvic pain, and rASRM stage, but not with age, BMI, menstrual disorder, and nulliparity. VEGFA, IL-4, IL-6, and CA-125 were increased in EMT patients and were inversely associated with miR-17-5p and miR-424-5p.

CONCLUSION

miR-424-5p combined with miR-17-5p has high diagnostic efficacy for EMT.

Combined proteomics and transcriptomics identifies serpin family C member 1 associated protein as a biomarker of endometriosis

OBJECTIVE

To explore potential biomarkers indicating endometriosis (EM).

MATERIALS AND METHODS

A proteomics method and combined quantitative transcriptomics were adopted to highlight markers in the EM. Venn analysis was used to integrate the ribonucleic acid sequencing (RNA-seq) and protein profiles. Promising candidate markers were tested by enzyme-related immunosorbent assay.

RESULTS

A sum of 979 mRNAs and 39 proteins were tested to be significantly differentially expression in the standard cluster compared with the EM cluster. Venn analysis showed a filtered signature of only two down-regulated molecules in the EM group, i.e. fetuin B (FETUB) and serpin family C member 1 (SERPINC1); the latter showed a big variance between the control category and the EM set in the authentication test.

CONCLUSION

SERPINC1 may be a useful possible biomarker for the analysis of EM.

Bioinformatics identification and validation of biomarkers and infiltrating immune cells in endometriosis

Background

Endometriosis (EM) is a common gynecological disorder that often leads to irregular menstruation and infertility. The pathogenesis of EM remains unclear and delays in diagnosis are common. Thus, it is urgent to explore potential biomarkers and underlying molecular mechanisms for EM diagnosis and therapies.

Methods

Three EM-related datasets (GSE11691, GSE25628, and GSE86534) were downloaded from the Gene Expression Omnibus (GEO) which were integrated into a combined dataset after removing batch effect. Differentially expressed immune cell-related genes were obtained by CIBERSORT, WGCNA, and the identification of differentially expressed genes. Random forest model (RF), support vector machine model (SVM), and generalized linear model (GLM) were then constructed and the biomarkers for EM were determined. A nomogram evaluating the risk of disease was constructed and the validity was assessed by the calibration curve, DCA curve, and clinical impact curve. Single-gene Gene Set Enrichment Analysis (GSEA)was performed to explore the molecular mechanisms of biomarkers. The ceRNA regulatory network of biomarkers was created by Cytoscape and potential target drugs were obtained in the DGIdb database (Drug-Gene Interaction database).The expression levels of biomarkers from clinical samples was quantified by RT-qPCR.

Results

The ratio of eight immune cells was significantly different between the eutopic and ectopic endometrium samples. A total of eight differentially expressed immune cell-related genes were investigated. The SVM model was a relatively suitable model for the prediction of EM and five genes (CXCL12, PDGFRL, AGTR1, PTGER3, and S1PR1) were selected from the model as biomarkers. The calibration curve, DCA curve, and clinical impact curve indicated that the nomogram based on the five biomarkers had a robust ability to predict disease. Single gene GSEA result suggested that all five biomarkers were involved in labyrinthine layer morphogenesis and transmembrane transport-related biological processes in EM. A ceRNA regulatory network containing 184 nodes and 251 edges was constructed. Seven drugs targeting CXCL12, 49 drugs targeting AGTR1, 16 drugs targeting PTGER3, and 21 drugs targeting S1PR1 were extracted as potential drugs for EM therapy. Finally, the expression of PDGFRL and S1PR1 in clinical samples was validated by RT-qPCR, which was consistent with the result of public database.

Conclusions

In summary, we identified five biomarkers (CXCL12, PDGFRL, AGTR1, PTGER3, and S1PR1) and constructed diagnostic model, furthermore predicted the potential therapeutic drugs for EM. Collectively, these findings provide new insights into EM diagnosis and treatment.

The gut microbiota and endometriosis: From pathogenesis to diagnosis and treatment

Endometriosis is a common gynecological disease, that often leads to pain and infertility. At present, the specific pathogenesis of endometriosis has not been clarified, but it may be closely related to an imbalance of sex hormones in the body, ectopic hyperplasia stimulated by immune inflammation, and invasion and escape based on tumor characteristics. Gut microbiota is associated with many inflammatory diseases. With the further study of the gut microbiota, people are paying increasing attention to its relationship with endometriosis. Studies have shown that there is an association between the gut microbiota and endometriosis. The specific ways and mechanisms by which the gut microbiota participates in endometriosis may involve estrogen, immune inflammation, and tumor characteristics, among others. Therefore, in the future, regulating gut microbiota disorders in various ways can help in the treatment of endometriosis patients. This study reviewed the research on the gut microbiota and endometriosis in order to provide ideas for clinical diagnosis and treatment.

Colocalization of senescent biomarkers in deep, superficial, and ovarian endometriotic lesions: a pilot study

Endometriosis is a prevalent gynecological condition with deleterious effects on women's quality of life in terms of physical, emotional, and social compromise. It is an inflammatory disease characterized by the presence of endometrial-like tissue outside the uterus, and its presentation varies from superficial peritoneal lesions to deep infiltrative endometriosis and ovarian endometrioma. In our previous study, endometriotic lesions were implicated in cellular senescence as their inflammatory pattern could potentially compromise surrounding tissue integrity, thereby inducing a senescent state in cells. P16^Ink4a and lamin b1 are biomarkers used to assess cellular senescence. Indirect immunofluorescence staining is a broad technique used to assess cellular structure and behavior driven by protein-protein interactions that provide valuable information about cell functioning. The etiopathogeny of endometriosis is not completely understood and diagnostic approaches still rely on invasive methods; therefore, it is important to use validated methods to increase our understanding of the disease and the development of novel diagnostic tools. However, indirect immunofluorescence protocols are often tissue specific and, if neglected, can lead to misinterpretation of results. Moreover, no valid endometriotic tissue-specific colocalization immunofluorescence protocols have been established. Thus, we have validated a well-funded and suitable protocol to allow precise evaluation of the three presentations of endometriosis lesions using indirect immunofluorescence aiming to support further investigations in endometriosis lesions.

Endometriosis biomarkers of the disease: an update

PURPOSE OF REVIEW

Endometriosis is a complex benign gynaecologic condition with heterogenous presentations and a large impact on the global healthcare system and on the quality of life for millions of women. Currently, the gold standard for diagnosis involves direct visualization of lesions during surgery confirmed by histopathological diagnosis, resulting in an average delay in its initial diagnosis of 8-10 years. Therefore, the search for noninvasive diagnostic testing options has been subject to a large body of research.

RECENT FINDINGS

Multiple potential biomarkers have been explored for noninvasive testing for endometriosis, including glycoproteins, inflammatory cytokines, immunological molecules, angiogenesis markers, hormones, micro RNAs (miRNAs), proteomics, metabolomics, genomics and the microbiome.

SUMMARY

Although there are challenges to consider, areas for real promise and advancement in the noninvasive diagnosis of endometriosis are currently being explored with real promise in the area of miRNAs, proteomics, metabolomics, genomics and the microbiome.

Revisiting the Risk Factors for Endometriosis: A Machine Learning Approach

Endometriosis is a condition characterized by implants of endometrial tissues into extrauterine sites, mostly within the pelvic peritoneum. The prevalence of endometriosis is under-diagnosed and is estimated to account for 5-10% of all women of reproductive age. The goal of this study was to develop a model for endometriosis based on the UK-biobank (UKB) and re-assess the contribution of known risk factors to endometriosis. We partitioned the data into those diagnosed with endometriosis (5924; ICD-10: N80) and a control group (142,723). We included over 1000 variables from the UKB covering personal information about female health, lifestyle, self-reported data, genetic variants, and medical history prior to endometriosis diagnosis. We applied machine learning algorithms to train an endometriosis prediction model. The optimal prediction was achieved with the gradient boosting algorithms of CatBoost for the data-combined model with an area under the ROC curve (ROC-AUC) of 0.81. The same results were obtained for women from a mixed ethnicity population of the UKB (7112; ICD-10: N80). We discovered that, prior to being diagnosed with endometriosis, affected women had significantly more ICD-10 diagnoses than the average unaffected woman. We used SHAP, an explainable AI tool, to estimate the marginal impact of a feature, given all other features. The informative features ranked by SHAP values included irritable bowel syndrome (IBS) and the length of the menstrual cycle. We conclude that the rich population-based retrospective data from the UKB are valuable for developing unified machine learning endometriosis models despite the limitations of missing data, noisy medical input, and participant age. The informative features of the model may improve clinical utility for endometriosis diagnosis.

Endometriosis and Subfertility: A Literature Review

Introduction: Endometriosis is a condition that mainly concerns women of reproductive age, which causes several problems, including subfertility. The phenotypic presentation of endometriosis is defined by a complex interplay between genetic profile, immunological and mechanical factors. In this literature review we examine the causality between endometriosis and subfertility, outlining possible mechanisms involved in the pathogenesis. Aim: The purpose of this study was to conduct a literature review in order to identify the correlation between endometriosis and subfertility through possible mechanisms involved in the pathogenesis of endometriosis-associated subfertility and treatment. Methods:A search in Medline/PubMed was done, using the terms "endometriosis" and "subfertility", to identify the most relevant studies that were published during the last six years. Results:Pathogenesis of endometriosis-associated subfertility is not clear yet, although some data indicate that there are several factors that could affect a patient's fertility. Involved mechanisms include mechanical obstruction such as ovarian tubal dysfunction and the abnormal peritoneal microenvironment, genetic, and epigenetic mechanisms, and immunological traits. It is fundamental to better understand these mechanisms in order to improve the therapeutic approach. Conclusions:The clinical management of endometiosis-related subfertility has to be improved. It is important to consider a change in the classification of endometriosis and, more importantly, an effort to avoid surgical procedures. There is a crucial need for effective protocols and novel targets for specific diagnosis and treatment. Consequently, the importance of understanding pathogenesis and genetic mechanisms is underlined. Future researchers should focus on novel non-invasive treatment methods that target specific pathogenic pathways.

Infertile women with endometriosis possess differences in cytokine levels in various tissues

OBJECTIVE

(1) To characterize the cytokine expression profiles of endometriosis related infertile women in comparison to fertile women with endometriosis; (2) to investigate the correlation of the cytokine levels from different tissues.

METHODS

100 stage IV endometriosis patients were recruited and grouped by infertility status (n = 50, separately). Concentrations of TNF-α, TGF-β1, IL-10, and IL-17A from the serum, peritoneal fluid (PF), eutopic, and ectopic endometrium samples were measured.

RESULTS

(1) In the infertile group, the concentrations of IL-10 within serum, PF and eutopic endometrium were all significantly higher (p = .022 and <.01, .013, respectively), the levels of TGF-β1 in serum and eutopic endometrium samples were both higher (p = .025 and p < .01), the levels of IL-17A in the PF, eutopic, and ectopic endometrium were all lower (p < .01, all). (2) Significant positive correlation was observed between IL-17A from PF and the ectopic endometrium (p = .014), IL-17A from PF and eutopic endometrium (p < .01). The PF IL-10 levels positively correlated with those in the serum (p = .007).

CONCLUSIONS

This is the first study comparing the levels of cytokines within four different tissues of endometriosis women with or without infertility. The study revealed that endometriosis-related infertile women possess significant differences in cytokine levels in comparison to fertile women with endometriosis. The levels of inflammatory factors from different tissues had certain positive correlations. Infertility may indicate the progress of the disease.

Antibody Arrays Identified Cycle-Dependent Plasma Biomarker Candidates of Peritoneal Endometriosis

Endometriosis is an estrogen-dependent inflammatory disease affecting women in their reproductive age. Due to non-specific symptoms, women with endometriosis are often misdiagnosed or are accurately diagnosed only after several years. Diagnosis of peritoneal endometriosis is especially challenging and relies only on laparoscopic surgery. To date, different molecules have been proposed as potential non-invasive biomarkers of endometriosis; however, none have been confirmed as clinically useful. Therefore, this study aimed to discover novel plasma biomarker candidates for peritoneal endometriosis using an antibody array platform. This study included patients with endometriosis-like symptoms characterized by the absence (controls) or presence of peritoneal endometriosis (cases) after laparoscopic surgery and histological evaluation. Patients were further divided into secretory and proliferative groups, according to the phase of their menstrual cycle. Their plasma samples were collected and analyzed on an antibody array platform targeting more than 1350 proteins with over 1820 antibodies. In the proliferative group, the analysis revealed three differential proteins between cases and controls: ITB3, ITA2B2, and ACVL-1. In the secretory group, none of the examined proteins reached the log-fold change (logFC) and significance thresholds simultaneously. The potential of the identified differential proteins as plasma biomarker candidates for peritoneal endometriosis should be evaluated on a larger cohort, and their role in endometriosis should be investigated in further studies.

BRAK and APRIL as novel biomarkers for ovarian tumors

Aims: To evaluate BRAK and APRIL in serum samples from healthy patients and an ovarian tumor group and analyze their effective value as biomarkers. Materials & methods: BRAK and APRIL were measured in 197 serum samples including 34 healthy controls, 48 patients with benign ovarian cysts and 115 patients with ovarian cancer, and the best statistical cutoff values were calculated. Then, the sensitivity, specificity, accuracy, positive predictive value and negative predictive value for selected cutoff points were assessed. Results: The healthy control group had statistically significant higher BRAK and lower APRIL than the ovarian tumor group. BRAK was excellent for differentiating healthy patients from patients with ovarian tumors, showing area under the receiver operating characteristic curve 0.983, 98.16% sensitivity and 100% specificity. When BRAK was combined with APRIL and CA-125, it also played a role in distinguishing benign cysts from malignancies with area under the curve 0.864, 81.74% sensitivity and 79.17% specificity. Conclusions: BRAK and APRIL are good candidates for ovarian tumor biomarkers.

Elevated Circulatory Proline to Glutamine Ratio (PQR) in Endometriosis and Its Potential as a Diagnostic Biomarker

Endometriosis (EM) is a hormone-dependent gynecological disease associated with chronic pelvic pain and altered immuno-inflammatory processes. It shares some cancer-like characteristics such as increased proline biosynthesis and activated glutaminolysis. Both proline and glutamine are interconvertible metabolically, and studies have shown their roles in cancer cell metabolic reprogramming, redox homeostasis, occurrence/development of endometrial carcinoma, and its further progression toward the malignant state. So based on this, we hypothesized that the circulatory proline to glutamine ratio (PQR) would be altered in EM and may serve as an indicative biomarker to improve the clinical diagnosis of EM. In present study, the circulatory-PQR levels were estimated for 39 EM patients and 48 age matched healthy female subjects using 800 MHz NMR spectroscopy. Among 39 EM patients, 15 were in the clinical stages I to II and referred to here as moderate EM (MEM) patients and 24 were in the clinical stages III to IV and referred here as severe EM (SEM) patients. The circulatory-PQR levels were significantly increased in EM patients (0.99 ± 0.13 μM in MEM; 1.39 ± 0.22 μM in SEM) compared to normal control (NC) subjects (0.52 ± 0.05 μM in NC). Further, the circulatory PQR levels exhibit the highest diagnostic potential with area under receiver operating characteristic (AUROC) curve values equal to 0.87 ± 0.04 [95%CI = 0.79-0.96] for MEM and 0.89 ± 0.04 [95% CI = 0.82-0.96] for SEM. These results suggested that circulatory-PQR has significant potential to serve as a noninvasive biomarker for diagnostic/prognostic screening of EM and further underscored the importance of these two nonessential amino acids (proline and glutamine) in cancer metabolism.

MicroRNome analysis generates a blood-based signature for endometriosis

Endometriosis, characterized by endometrial-like tissue outside the uterus, is thought to affect 2–10% of women of reproductive age: representing about 190 million women worldwide. Numerous studies have evaluated the diagnostic value of blood biomarkers but with disappointing results. Thus, the gold standard for diagnosing endometriosis remains laparoscopy. We performed a prospective trial, the ENDO-miRNA study, using both Artificial Intelligence (AI) and Machine Learning (ML), to analyze the current human miRNome to differentiate between patients with and without endometriosis, and to develop a blood-based microRNA (miRNA) diagnostic signature for endometriosis. Here, we present the first blood-based diagnostic signature obtained from a combination of two robust and disruptive technologies merging the intrinsic quality of miRNAs to condense the endometriosis phenotype (and its heterogeneity) with the modeling power of AI. The most accurate signature provides a sensitivity, specificity, and Area Under the Curve (AUC) of 96.8%, 100%, and 98.4%, respectively, and is sufficiently robust and reproducible to replace the gold standard of diagnostic surgery. Such a diagnostic approach for this debilitating disorder could impact recommendations from national and international learned societies.

Differential Expression and Bioinformatics Analysis of tRF/tiRNA in Endometriosis Patients

Background. Endometriosis (EMs) is a benign chronic condition that tends to recur in women of childbearing age, with an incidence of approximately 10%. It is a multifactorial disease for which the pathogenesis is currently unclear. This study is aimed at investigating the expression and clinical significance of tRNA-derived small RNA (tsRNA), a novel noncoding small RNA with potential regulatory functions, in endometriosis. Methods. The tRF/tiRNA expression profiles in endometrial tissues from three pairs of endometriosis patients and controls were detected by tRF&tiRNA PCR microarray technology and then verified by quantitative real-time polymerase chain reaction (qPCR). The target genes and target sites of TRF396, tiRNA-5030-GlnTTG-3, TRF308, and TRF320 were predicted by miRanda, and the network diagram of their interaction with miRNA was drawn. The impact of tRNA-derived fragments on the pathogenesis of endometriosis was analyzed using the Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG). Results. Two upregulated and 19 downregulated tRNA-derived fragments were identified. The qRT-PCR results of 2 upregulated and 2 downregulated RNA-derived fragments were consistent with the RNA Seq data. The OR2B4 gene related to TRF396, the DGAT1 gene related to tiRNA-5030-GlnTTG-3, the KLF16 gene of TRF308, and the RNF213 gene of TRF320 had significant correlations. Gene Ontology and pathway analysis showed that the target genes of TRF396 and tiRNA-5030-GlnTTG-3 were mainly involved in the intrinsic components of the membrane and the overall composition of the membrane in cell components; molecular functions mainly involve olfactory conduction and G protein-coupled receptor activity. In the biological process, it was mainly involved in the detection of sensory stimuli. The target genes of TRF308 and TRF320 were mainly involved in the intracellular part; molecular functions are mainly related to DNA binding transcription factor activity and protein binding and mainly related to biological regulation of biological processes. Pathway analysis showed that the RAP1 signaling pathway and the AXON GUIDANCE signaling pathway may participate in the progression of endometriosis. Conclusion. The differential expression of tRF/tiRNA in endometriosis may be related to the pathogenesis of endometriosis. Furthermore, tRF/tiRNA may be a biomarker for the diagnosis and treatment of EMs in the future.

Endometriosis and adverse pregnancy outcome

INTRODUCTION

Endometriosis is a gynecologic disease affecting approximately 10% of reproductive age women, around 21-47% of women presenting subfertility and 71-87% of women with chronic pelvic pain. Main symptoms are chronic pelvic pain, dysmenorrhea, dyspareunia and infertility that seem to be well controlled by oral contraceptive pill, progestogens, GnRh antagonists. The aim of this review was to illustrate the modern diagnosis of endometriosis during pregnancy, to evaluate the evolution of endometriotic lesions during pregnancy and the incidence of adverse outcomes.

EVIDENCE ACQUISITION

Published literature was retrieved through searches of the database PubMed (National Center for Biotechnology Information, US National Library of Medicine, Bethesda, MD, USA). We searched for all original articles published in English through April 2020 and decided to extract every notable information for potential inclusion in this review. The search included the following MeSH search terms, alone or in combination: "endometriosis" combined with "endometrioma," "biomarkers," "complications," "bowel," "urinary tract," "uterine rupture," "spontaneous hemoperitoneum in pregnancy" and more "adverse pregnancy outcome," "preterm birth," "miscarriage," "abruption placentae," "placenta previa," "hypertensive disorder," "preeclampsia," "fetal grow restriction," "small for gestation age," "cesarean delivery."

EVIDENCE SYNTHESIS

Pregnancy in women with endometriosis does not always lead to disappearance of symptoms and decrease in the size of endometriotic lesions, but it may be possible to observe a malignant transformation of ovarian endometriotic lesions. Onset of complications may be caused by many factors: chronic inflammation, adhesions, progesterone resistance and a dysregulation of genes involved in the embryo implantation. As results, the pregnancy can be more difficult because of endometriosis related complications (spontaneous hemoperitoneum [SH], bowel complications, etc.) or adverse outcomes like preterm birth, FGR, hypertensive disorders, obstetrics hemorrhages (placenta previa, abruptio placenta), miscarriage or cesarean section. Due to insufficient knowledge about its pathogenesis, currently literature data are contradictory and do not show a strong correlation between endometriosis and these complications except for miscarriage and cesarean delivery.

CONCLUSIONS

Future research should focus on the potential biological pathways underlying these relationships in order to inform patients planning a birth about possible complications during pregnancy.

Salivary MicroRNA Signature for Diagnosis of Endometriosis

BACKGROUND

Endometriosis diagnosis constitutes a considerable economic burden for the healthcare system with diagnostic tools often inconclusive with insufficient accuracy. We sought to analyze the human miRNAome to define a saliva-based diagnostic miRNA signature for endometriosis.

METHODS

We performed a prospective ENDO-miRNA study involving 200 saliva samples obtained from 200 women with chronic pelvic pain suggestive of endometriosis collected between January and June 2021. The study consisted of two parts: (i) identification of a biomarker based on genome-wide miRNA expression profiling by small RNA sequencing using next-generation sequencing (NGS) and (ii) development of a saliva-based miRNA diagnostic signature according to expression and accuracy profiling using a Random Forest algorithm.

RESULTS

Among the 200 patients, 76.5% (n = 153) were diagnosed with endometriosis and 23.5% (n = 47) without (controls). Small RNA-seq of 200 saliva samples yielded ~4642 M raw sequencing reads (from ~13.7 M to ~39.3 M reads/sample). Quantification of the filtered reads and identification of known miRNAs yielded ~190 M sequences that were mapped to 2561 known miRNAs. Of the 2561 known miRNAs, the feature selection with Random Forest algorithm generated after internally cross validation a saliva signature of endometriosis composed of 109 miRNAs. The respective sensitivity, specificity, and AUC for the diagnostic miRNA signature were 96.7%, 100%, and 98.3%.

CONCLUSIONS

The ENDO-miRNA study is the first prospective study to report a saliva-based diagnostic miRNA signature for endometriosis. This could contribute to improving early diagnosis by means of a non-invasive tool easily available in any healthcare system.