Downregulation of lncrna uca1 as a diagnostic and prognostic biomarker for ovarian endometriosis

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.

A comprehensive overview of exosome lncRNAs: emerging biomarkers and potential therapeutics in endometriosis

Endometriosis is a gynecological condition that significantly impacting women's daily lives. In recent years, the incidence of endometriosis has been rising yearly and is now an essential contributor to female infertility. Exosomes are extracellular vesicles (EVs) that carry long noncoding RNA (lncRNA) and shield lncRNA from the outside environment thanks to their vesicle-like structure. The role of exosome-derived lncRNAs in endometriosis is also receiving more study as high-throughput sequencing technology develops. Several lncRNAs with variable expression may be crucial to the emergence and growth of endometriosis. The early diagnosis of endometriosis will be considerably improved by further high specificity and sensitivity Exosome lncRNA screening. Exosomes assist lncRNAs in carrying out their roles, offering a new target for creating endometriosis-specific medications. In order to serve as a reference for clinical research on the pathogenesis, diagnosis, and treatment options of endometriosis, this paper covers the role of exosome lncRNAs in endometriosis and related molecular mechanisms.

Cross-Talk between N6-Methyladenosine and Their Related RNAs Defined a Signature and Confirmed m6A Regulators for Diagnosis of Endometriosis

An RNA modification known as N6-methyladenosine (m6A) interacts with a range of coding and non-coding RNAs. The majority of the research has focused on identifying m6A regulators that are differentially expressed in endometriosis, but it has ignored their mechanisms that are derived from the alterations of modifications among RNAs, affecting the disease progression primarily. Here, we aimed to investigate the potential roles of m6A regulators in the diagnostic potency, immune microenvironment, and clinicopathological features of endometriosis through interacting genes. A GEO cohort was incorporated into this study. Variance expression profiling was executed via the "limma" R package. Pearson analysis was performed to investigate the correlations among 767 interacting lncRNAs, 374 interacting mRNAs, and 23 m6A regulators. K-means clustering analysis, based on patterns of mRNA modifications, was applied to perform clinical feature analysis. Infiltrating immune cells and stromal cells were calculated using the Cibersort method. An m6A-related risk model was created and supported by an independent risk assay. LASSO regression analysis and Cox analyses were implemented to determine the diagnostic genes. The diagnostic targets of endometriosis were verified using PCR and the WB method. Results: A thorough investigation of the m6A modification patterns in the GEO database was carried out, based on mRNAs and lncRNAs related to these m6A regulators. Two molecular subtypes were identified using unsupervised clustering analysis, resulting in further complex infiltration levels of immune microenvironment cells in diversified endometriosis pathology types. We identified two m6A regulators, namely METTL3 and YTHDF2, as diagnostic targets of endometriosis following the usage of overlapping genes to construct a diagnostic m6A signature of endometriosis through multivariate logistic regression, and we validated it using independent GSE86534 and GSE105764 cohorts. Finally, we found that m6A alterations might be one of the important reasons for the progression of endometriosis, especially with significant downregulation of the expressions of METTL3 and YTHDF2. Finally, m6A modification patterns have significant effects on the diversity and complexity of the progression and immune microenvironment, and might be key diagnostic markers for endometriosis.

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.

The Critical Roles of Circular RNAs in Basic Research and Clinical Application of Female Reproductive-Related Diseases

Circular RNAs (circRNAs), produced by precursor mRNAs, are a type of covalently closed circular molecule without 5' caps and 3' polyadenylated tails. Recently, advances in high-throughput sequencing, transcriptomics and bioinformatics, have revealed that circRNAs with specific traits in tissue or cells play emerging roles in both physiological and panthological contexts instead of as simple by-products of transcription. However, bringing circRNAs to the forefront of clinical practice is still a long way off. In this review, we highlight the progress in the formation and function of circRNAs, and how circRNAs work in female reproductive-related diseases, such as recurrent spontaneous abortion, preeclampsia, and endometriosis. We also discussed the clinical potential of circRNAs as biomarkers, and therapeutic agents in female reproductive diseases as well as research controversies, technical issues, and biological knowledge gaps that need to be addressed. This review may instruct future basic research and clinical applications on circRNAs, especially in female reproduction.

Analysis of Long Non-Coding RNA (lncRNA) UCA1, MALAT1, TC0101441, and H19 Expression in Endometriosis

Endometriosis is a disease of complex etiology. Hormonal, immunological, and environmental factors are involved in its formation. In recent years, special attention has been paid to genetic mechanisms that can have a significant impact on the increased incidence of endometriosis. The study aimed to analyze the expression of four long non-coding RNA (lncRNA) genes, UCA1, MALAT1, TC0101441, and H19, in the context of the risk of developing endometriosis. The material for genetic testing for the expression of lncRNA genes were tissue slices embedded in paraffin blocks from patients with endometriosis (n = 100) and the control group (n = 100). Gene expression was determined by the RT-PCR technique. The expression of the H19 gene in endometriosis patients was statistically significantly lower than in the control group. A statistically significant association was found between H19 gene expression in relation to The Revised American Society for Reproductive Medicine classification of endometriosis (rASRM) in the group of patients with endometriosis. Research suggests that H19 expression plays an important role in the pathogenesis of endometriosis.

Expression of lncRNA NEAT1 in endometriosis and its biological functions in ectopic endometrial cells as mediated via miR-124-3p

BACKGROUND

Endometriosis (EM) is a gynecological disease that poses severe health risks to women, although its pathogenesis has yet to be fully elucidated. It has been shown that long non-coding RNAs (lncRNAs) are closely associated with EM initiation and have a role in the development of this disease. Previous studies exploring the expression of the lncRNA nuclear paraspeckle assembly transcript 1 (NEAT1) have shown that this lncRNA functions as a tumor promoter in endometrial cancer. However, its exact mechanism of action in EM remains unclear.

OBJECTIVE

This report was designed to illustrate the potential molecular mechanisms of lncRNA NEAT1 on EM.

METHODS

Endometrial tissues were extracted from EM model rats and patients with EM. Hematoxylin and eosin staining was applied to detect the morphological changes that occurred in rats after construction of the model. Endometrial stromal cells (ESCs) were extracted from either ectopic endometrium (EC) or eutopic endometrium (EU) tissues from patients with EM. LncRNA NEAT1 and miR-124-3p expression in EM tissues and cells were subsequently evaluated by reverse transcription-quantitative (RT-q)PCR analysis. MTT assay, flow cytometric analysis, western blot assay and Transwell assay were then employed to examine the effect of NEAT1 and miR-124-3p on EC-ESC proliferation, apoptosis, migration and invasion, respectively. The targeted relationship between lncRNA NEAT1 and miR-124-3p was subsequently confirmed by dual-luciferase and co-transfection assays.

RESULTS

MiR-124-3p was identified as a target of NEAT1, and could be negatively regulated by NEAT1 in EC-ESCs. The expression level of NEAT1 was evidently increased, whereas that of miR-124-3p was decreased, in the EM in vivo model, EM tissues and EC-ESCs from patients with EM. The loss-of-function assays further established that silencing of NEAT1 could inhibit EC-ESC proliferation, migration, and invasion, but it led to the promotion of apoptosis via targeting miR-124-3p.

CONCLUSIONS

NEAT1 is significantly upregulated in EM, promoting malignant behavior in EM through targeting miR-124-3p expression.

Long Noncoding RNA Mediated Regulation in Human Embryogenesis, Pluripotency, and Reproduction

Long noncoding RNAs (lncRNAs), a class of noncoding RNAs with more than 200 bp in length, are produced by pervasive transcription in mammalian genomes and regulate gene expression through various action mechanisms. Accumulating data indicate that lncRNAs mediate essential biological functions in human development, including early embryogenesis, induction of pluripotency, and germ cell development. Comprehensive analysis of sequencing data highlights that lncRNAs are expressed in a stage-specific and human/primate-specific pattern during early human development. They contribute to cell fate determination through interacting with almost all classes of cellular biomolecules, including proteins, DNA, mRNAs, and microRNAs. Furthermore, the expression of a few of lncRNAs is highly associated with the pathogenesis and progression of many reproductive diseases, suggesting that they could serve as candidate biomarkers for diagnosis or novel targets for treatment. Here, we review research on lncRNAs and their roles in embryogenesis, pluripotency, and reproduction. We aim to identify the underlying molecular mechanisms essential for human development and provide novel insight into the causes and treatments of human reproductive diseases.

A diagnostic and prognostic value of blood-based circulating long non-coding RNAs in Thyroid, Pancreatic and Ovarian Cancer

Several studies have demonstrated the potential of circulating long non-coding RNAs (lncRNAs) as promising cancer biomarkers. Herein, we addressed the regulatory role of circulating lncRNAs and their potential value as diagnostic/prognostic markers for thyroid, pancreatic and ovarian cancers. Furthermore, we analyzed and measured the clinical implications and association of lncRNAs with sensitivity, specificity, and area under the ROC curve (AUC). Based on our meta-analysis, we found that GAS8-AS1 could discriminate thyroid cancer from non-cancer and other cancers with higher accuracy (AUC = 0.746; sensitivity = 61.70%, and specificity = 90.00%). Similarly, for ovarian cancer, lncRNA RP5-837J1.2 was found to have ideal diagnostic potential with critical clinical specifications of AUC = 0.996; sensitivity = 97.30% and specificity = 94.60%. Whereas we could not find any lncRNA having high diagnostic/prognostic efficiency in pancreatic cancer. We believe that lncRNAs mentioned above may explore clinical settings for the diagnosis and prognosis of cancer patients.

miRNAs and lncRNAs: Potential Non-Invasive Biomarkers for Endometriosis

Many studies have tried to understand the mechanism of endometriosis and its manner of manifestation. However, the only method of diagnosis considered as the gold standard in endometriosis is an invasive method called exploratory laparoscopy. Hence, there is a need to identify non-invasive or minimally invasive methods to minimize patients' suffering, thus increasing their addressability at the earliest possible staging of the disease, and to diagnose this condition as soon as possible. miRNAs (microRNAs) and lncRNAs (long-noncoding RNAs) are potential non-invasive diagnostic methods for endometriosis. Multiple clinical trials indicate that miRNA can be used as a non-invasive method in the diagnosis and differentiation of endometriosis stages.

Translational Applications of Linear and Circular Long Noncoding RNAs in Endometriosis

Endometriosis is a chronic gynecologic disease that negatively affects the quality of life of many women. Unfortunately, endometriosis does not have a cure. The current medical treatments involve hormonal manipulation with unwanted side effects and high recurrence rates after stopping the medication. Sadly, a definitive diagnosis for endometriosis requires invasive surgical procedures, with the risk of complications, additional surgeries in the future, and a high rate of recurrence. Both improved therapies and noninvasive diagnostic tests are needed. The unique molecular features of endometriosis have been studied at the coding gene level. While the molecular components of endometriosis at the small RNA level have been studied extensively, other noncoding RNAs, such as long intergenic noncoding RNAs and the more recently discovered subset of long noncoding RNAs called circular RNAs, have been studied more limitedly. This review describes the molecular formation of long noncoding and the unique circumstances of the formation of circular long noncoding RNAs, their expression and function in endometriosis, and promising preclinical studies. Continued translational research on long noncoding RNAs, including the more stable circular long noncoding RNAs, may lead to improved therapeutic and diagnostic opportunities.

Exploring the Potential Key IncRNAs with Endometriosis by Construction of a ceRNA Network

Purpose

The etiology and pathophysiology of endometriosis remain unclear. Current research indicates long noncoding RNA (lncRNA) may play an important role in the pathogenesis and development of endometriosis. However, the molecular mechanism of lncRNA in endometriosis is far from clear.

Patients and Methods

The lncRNA and mRNA expression of 8 patients with ovarian endometriosis were determined by high-throughput RNA sequencing (8 ectopic endometria samples vs 8 eutopic endometria samples), and miRNA expression profiles were obtained from our previous study. Then a lncRNA-associated competing endogenous RNA (ceRNA) network was constructed by combining the regulatory interaction and negative co-expression interaction between the differentially expressed lncRNAs/mRNAs and miRNAs by different rules.

Results

The constructed lncRNA-related ceRNA network was composed of two separate networks, network 1 including 14,137 dysregulated lncRNA–mRNA interactions, referring to 242 lncRNAs, 55 miRNAs and 1600 mRNAs, network 2 including 4459 dysregulated lncRNA–mRNA interactions, referring to 111 lncRNAs, 39 miRNAs and 1151 mRNAs. The top six hub lncRNAs (LINC01140, MSC-AS1, HAGLR, CKMT2-AS1, JAKMIP2-AS1, AL365361.1) in the significant ternary relationship of mRNA–miRNA–lncRNA in network 1, and the top six hub lncRNAs (PAX8-AS1, MIR17HC, PART1, HOXA-AS3, PLAC4, LINC00511) in the significant ternary relationship of mRNA–miRNA–lncRNA in network 2 were selected. Functional enrichment analysis of these lncRNA-related mRNAs indicated that the lncRNAs in network 1 mainly take part in positive regulation of phagocytosis, myeloid leukocyte activation, and tissue remodeling, while the lncRNAs in network 2 mainly take part in negative regulation of cell proliferation, blood vessel development and regulation of epithelial cell differentiation, which is consistent with the results obtained from the different rules to construct the networks.

Conclusion

lncRNA-related ceRNA network analysis recognized key lncRNAs related to the development of endometriosis.

LncRNA AFAP1-AS1 regulates proliferation and apoptosis of endometriosis through activating STAT3/TGF-β/Smad signaling via miR-424-5p

AIM

Endometriosis is a common gynecological disorder characterized by chronic pelvic pain and infertility, which negatively affects women's health worldwide. AFAP1-AS1 has been implicated in endometriosis lesions recently, but its mechanism of endometriosis progression remains unclear.

METHODS

Endometrial stromal cells (ESCs) were used to identify the role of AFAP1-AS1 in endometriosis. The migratory capability was determined by transwell. Gene and protein expressions were identified by quantitative real-time polymerase chain reaction (qRT-PCR) and Western blotting. Cell viability and apoptosis were detected by MTT assays and flow cytometry, respectively. Luciferase report assays were used to identify the interaction of AFAP1-AS1, miR-424-5p and signal transducer and activator of transcription 3 (STAT3).

RESULTS

AFAP1-AS1 knockdown or miR-424-5p overexpression inhibited proliferation and migration, and promoted apoptosis in ESCs. In addition, knockdown of AFAP1-AS1 repressed the expression of ki-67 and Bcl-2, and promoted the levels of cleaved caspase-3 and Bax. Furthermore, knockdown of AFAP1-AS1 inhibited the conversion of E-cadherin to N-cadherin and the expression of Snail. Moreover, AFAP1-AS1 activated the STAT3/transforming growth factor-β1 (TGF-β1)/Smad2 axis via directly targeting miR-424-5p. The regulatory effect of AFAP1-AS1 silencing in ESC migration, proliferation, and apoptosis was reversed by miR-424-5p inhibition or STAT3 overexpression.

CONCLUSIONS

AFAP1-AS1 silencing could inhibit cell proliferation and promote apoptosis by regulating STAT3/TGF-β/Smad signaling pathway via targeting miR-424-5p in ESCs. AFAP1-AS1 may be a potential therapeutic target of controlling the progression of endometriosis.

The value of long noncoding RNAs for predicting the recurrence of endometriosis: A protocol for meta-analysis and bioinformatics analysis

BACKGROUND

As a gynecological disease, endometriosis (EM) seriously endangers the health of women at the age of childbearing and is closely related to long noncoding RNAs (lncRNAs). Current studies have discovered that there are differential expressions of many kinds of lncRNAs in EM. However, whether lncRNAs can be applied as a new marker for the prediction of the recurrence of EM is still controversial. In this study, meta-analysis and bioinformatics analysis were carried out to explore the value of lncRNAs as a predictor of the recurrence of EM and to analyze its biological role.

METHODS

PubMed, Embase, and Web of Science databases were searched through computer and the articles published from the self-built database to April 2021 were collected. According to the inclusion and exclusion criteria, the literature was screened, and the quality of the inclusion study was evaluated. Stata 16.0 software was used for meta-analysis. The co-expression genes related to lncRNAs were screened by online tool Co-LncRNA. Then David for Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analysis were conducted. A competitive endogenous RNA network that may exist in lncRNAs through Starbase was built.

RESULTS

The results of this meta-analysis would be submitted to peer-reviewed journals for publication.

CONCLUSION

This meta-analysis could provide high-quality evidence support for lncRNAs, so as to predict the recurrence of EM. At the same time, we use bioinformatics technology to predict and analyze its biological effects, which provides a theoretical basis for further experimental verification.

ETHICS AND DISSEMINATION

The private information from individuals will not be published. This systematic review also should not damage participants' rights. Ethical approval is not available. The results may be published in a peer-reviewed journal or disseminated in relevant conferences.

OSF REGISTRATION NUMBER

DOI 10.17605/OSF.IO/MF3QJ.

Long non-coding RNAs in endometrial physiology and pathophysiology

The endometrium is an essential component of the female uterus which provides the environment for pregnancy establishment and maintenance. Abnormalities of the endometrium not only lead to difficulties in establishing and maintaining pregnancy but also play a causative role in diseases of endometrial origin including endometriosis and endometrial cancer. Non-coding RNAs are proposed to play a role in regulating the genome in both normal endometrial physiology and pathophysiology. In this review, we first provide a general overview of non-coding RNAs and reproductive physiology of the endometrium. We then discuss the role on non-coding RNAs in normal endometrial physiology and pathophysiology of endometrial infertility. We then conclude with non-coding RNAs in the pathophysiology of endometriosis and endometrial cancer.

Role of lncRNA FTX in invasion, metastasis, and epithelial-mesenchymal transition of endometrial stromal cells caused by endometriosis by regulating the PI3K/Akt signaling pathway

Background

Studies have considered long non-coding RNA 5 prime to Xist (lncRNA FTX) a key lncRNA for normal uterine development, but it has not been reported whether lncRNA FTX is involved in regulating the development of endometriosis (EMs). The aim of the present study was to explore the effect and mechanism of long non-coding RNA 5 prime to Xist (lncRNA FTX) on the invasion, metastasis, and epithelial-mesenchymal transition (EMT) of endometrial stromal cells (ESCs) caused by EMs.

Methods

Ectopic or normal endometrial tissues were collected from 38 patients with EMs, who were diagnosed and operated on at Beijing Tongren Hospital from June 2018 to December 2019, and 20 healthy volunteers with normal endometria. The expression of lncRNA FTX in both groups was detected by quantitative reverse transcription polymerase chain reaction. Ectopic endometrial stromal cells (EESC) and ESC from patients with EMs and healthy volunteers were separated and cultured, and the expression of lncRNA FTX in the cells was detected. The expression of lncRNA FTX in EESC was overexpressed or interfered. Proliferation, invasion, and migration was detected by Cell Counting Kit-8, transwell assay, and scratch assay. Apoptosis and cell cycle were detected by flow cytometry. EMT-related protein and PI3K/Akt signaling pathway-related protein expressions were detected by Western blot.

Results

LncRNA FTX was underexpressed in endometrial tissues and EESC from patients with EMs. The overexpression of lncRNA FTX could significantly inhibit the proliferation, invasion, and migration of EESC, but promoted apoptosis and cell cycle arrest in the G0/G1 phase. The overexpression of lncRNA FTX significantly increased the expression of EMT-related protein, E-cadherin, and decreased the protein expression of vimentin, N-cadherin, and zinc finger E-box binding homeobox 1. In addition, the overexpression of lncRNA FTX could decrease the expression of p-PI3K/PI3K and p-Akt/Akt. Interfering with the expression of lncRNA FTX had the opposite result.

Conclusions

The overexpression of lncRNA FTX could decrease the invasion, metastasis, and EMT of ESC caused by EMs by inhibiting the activity of the PI3K/Akt signaling pathway.

LncRNA MALAT1 inhibits apoptosis of endometrial stromal cells through miR-126-5p-CREB1 axis by activating PI3K-AKT pathway

Endometriosis is a common, chronic and painful disease in women, whose pathogenesis remains not entirely clear. Long non-coding RNA (lncRNA) MALAT1 participates in the development of endometriosis. This study further investigated the regulation of MALAT1-miR-126-5p-CREB1 axis in the pathological process of endometriosis. MALAT1, miR-126-5p, and CREB1 levels in human endometrial stromal cells (HESCs) were detected by quantitative reverse transcription polymerase chain reaction (RT-qPCR). Protein levels were determined by Western blotting. Cell viability and apoptosis was assessed by MTT assay and annexin V-FITC staining, respectively. The interactivity between miR-126-5p and MALAT1 (or CREB1) was assessed by dual luciferase reporter system. Knockdown of MALAT1 or CREB1 restrained proliferation and induced apoptosis as confirmed by upregulating cleaved caspase-3 and Bax, and down-regulating Bcl-2 in HESCs, while inhibition of miR-126-5p presented the opposite results. Moreover, silencing of MALAT1 triggered apoptosis of HESCs via targeting miR-126-5p. In addition, miR-126-5p directly regulated CREB1 expression via binding to its 3' non-coding region. Finally, miR-126-5p inhibitor-mediated apoptosis inhibition was restrained by CREB1 silencing via inactivation of PI3K-AKT pathway in HESCs. Taken together, our study firstly demonstrates that MALAT1 regulates apoptosis of HESCs through miR-126-5p/CREB1 axis mediated PI3K/AKT pathway. Our findings explained the pathogenesis of endometriosis and offered promising therapeutic option for endometriosis.

Role of Non-coding RNAs in the Pathogenesis of Endometriosis

Endometriosis is a disorder characterized by the presence of endometrial glands and stroma like lesions outside of the uterus. Although several hypothesis have tried to explain the underlying cause of endometriosis, yet the main cause remained obscure. Recent studies have shown contribution of non-coding RNAs in the pathogenesis of endometriosis. Two classes of these transcripts namely long non-coding RNAs (lncRNAs) and microRNAs (miRNAs) have mostly attracted attention of researchers. Several studies have reported aberrant expression of these transcripts in affected tissues from patients as well as animal models. Modulation of important signaling pathways such as PI3K/AKT, P38-MAPK, ERK1/2-MAPK and Wnt-β catenin by miRNAs and lncRNAs have potentiated these molecules as biomarkers or therapeutic agents in endometriosis. Single nucleotide polymorphisms with miR-126, miR-143 and miR-146b have been associated with risk of endometriosis. Moreover, miRNAs and lncRNAs control inflammatory responses, cell proliferation, angiogenesis and tissue remodeling, thus understanding the role of these transcripts in endometriosis is a possible way to develop novel diagnostic tests and therapeutic targets for this disorder.

Long noncoding RNAs in endometriosis: Biological functions, expressions, and mechanisms

Endometriosis refers to a benign chronic gynecological disorder, and is defined as the ectopic growth of endometrium in pelvic cavity. Endometriosis affects about 10% of reproductive-aged women. Unfortunately, the pathogenesis of endometriosis remains obscure, and the disease witnesses a lack of effective therapy approaches. Therefore, more research needs to be performed to throw light on endometriosis, its pathogenesis, and therapy. Long noncoding RNAs (lncRNAs), which are defined as functional cellular RNA longer than 200 nucleotides, have been implicated in many chronic disorders. It has been suggested that lncRNAs are closely related to the endometriosis process. Nevertheless, the molecular mechanisms by which lncRNAs associate with endometriosis should be elucidated more detailed. In our brief review, we first exhibit the aberrant lncRNAs expression in endometriosis. Then, we talk about the molecular mechanisms underlying lncRNAs in endometriosis. Finally, we also present the potential of lncRNAs as biomarkers for endometriosis.

Challenges in uncovering non-invasive biomarkers of endometriosis

Endometriosis affects up to 10% of women of childbearing age, causing symptoms that can include chronic pelvic pain and reduced fertility. The symptoms are not specific to the disease and can be confused with other gynecological conditions or normal menstruation. Currently, the disease can be only definitively diagnosed by laparoscopy, as no clinically accepted biomarker exists. Biomarker discovery can either follow a hypothesis-driven approach selecting targets to be tested based on current knowledge of the disease, or take an unbiased high-throughput screening “omics” approach, such as transcriptomics or proteomics, to identify markers that are unique or elevated in accessible bodily fluids of patients with the disease. Numerous studies have been conducted using these approaches to try and identify endometriosis biomarkers, but variabilities in study design, cohort selection, and analysis, together with the fact that most studies were small-scale, have made independent validation of biomarker candidates difficult. Therefore, efforts are underway to standardize cohort selection, patient data, and sample collection to allow better cross-study comparisons. Large scale multi-center studies using this standardized approach are necessary to validate existing endometriosis biomarker candidates and uncover potential new markers. Given the complexity and heterogeneity of the disease, it is likely that a panel of biomarkers will be necessary to diagnose and categorize endometriosis.

Circulating non-coding RNAs as non-invasive diagnostic markers of endometriosis: a comprehensive meta-analysis

BACKGROUND

Circulating non-coding RNAs have great potential for diagnosing endometriosis as non-invasive markers. We have assessed the potential accuracy and utility for diagnosis of endometriosis.

METHODS

We searched many bases to identify the included literature, which included English bases, such as, Pubmed, Embase, Web of Science, Cochrane library and Chinese bases, for instance, CNKI, Wang Fang, VIP, DuXiu, ChaoXing. We also calculated the general sensitivity and specificity, negative likelihood ratio, positive likelihood ratio, diagnostic odds ratio, ROC curve plotting and so on with Stata 15. I² could test the heterogeneity of the meta-analysis, the funnel plot valuated whether meta-analysis had a publication bias. Regression analysis could explore heterogeneity in studies.

RESULT

Comprehensive reading and integrating extracted data, we included 11 published papers. The total number of people included in the case group was 453, and the control group was 362. We, respectively, calculated the general sensitivity and general specificity which were 0.81 (95% CI 0.76-0.85) and 0.77 (95% CI 0.71-0.82) by bivariate analysis. The area under the ROC curve was 0.86 (95% CI 0.83-0.89). There was significant heterogeneity in studies which is I² = 89.62% (95% CI 87.41%-91.83%). In addition, the results of meta-regression and subgroup analysis showed that the heterogeneity might come from gold standard, evaluation standard, experimental group size, experimental sample and race CONCLUSION: The circulating non-coding RNAs have great ability of diagnosing endometriosis as non-invasive markers which were performed robustly and accurately.