Silencing of SRA1 Regulates ER Expression and Attenuates the Growth of Stromal Cells in Ovarian Endometriosis

Therapeutic significance of long noncoding RNAs in estrogen receptor-positive breast cancer

About 70% of cases of breast cancer are compromised by Estrogen-positive breast cancer. Through its regulation of several processes, including cell proliferation, cell cycle progression, and apoptosis, Estrogen signaling plays a pivotal role in the genesis and progression of this particular kind of breast cancer. One of the best treatment strategies for treating Estrogen-positive breast cancer is blocking Estrogen signaling. However, patients' treatment failure is mainly caused by the emergence of resistance and metastases, necessitating the development of novel therapeutic targets. Numerous studies have shown long noncoding RNAs (lncRNAs) to play a role in Estrogen-mediated carcinogenesis. These lncRNAs interact with co-regulators and the Estrogen signaling cascade components, primarily due to Estrogen activation. Vimentin and E-cadherin are examples of epithelial-to-mesenchymal transition markers, and they regulate genes involved in cell cycle progression, such as Cyclins, to affect the growth, proliferation, and metastasis of Estrogen-positive breast cancer. Furthermore, a few of these lncRNAs contribute to developing resistance to chemotherapy, making them more desirable targets for enhancing results. Thus, to shed light on the creation of fresh approaches for treating this cancer, this review attempts to compile recently conducted studies on the relationship between lncRNAs and the advancement of Estrogen-positive breast cancer.

Downregulation of lncRNA LINC01465 predicts ovarian endometriosis and its prognosis

The well-known impact of ovarian endometriosis on female quality of life and the established role of lncRNA LINC01465 in ovarian cancer pathogenesis have been extensively documented; however, the relationship between LINC01465 and ovarian endometriosis is still not clear. This study seeks to explore the potential involvement of LINC01465 in the disease. The study analyzed a sample of 80 endometriosis patients and 80 healthy women. The expression of LINC01465 was measured in ectopic and eutopic endometrial tissues through RT-qPCR. The diagnostic potential of serum LINC01465 levels was evaluated using ROC curve analysis, and the patients were followed up for 3 years after treatment to monitor recurrence. The results revealed that the expression of LINC01465 was significantly lower in ectopic endometrial tissues in comparison to paired eutopic tissues for most of the patients. No correlation was found between the patient's age or lifestyle and serum LINC01465 levels. After treatment, the serum LINC01465 level increased, and patients who experienced recurrence had significantly lower levels compared to those who did not. In conclusion, the study findings suggest that the downregulation of LINC01465 plays a role in the pathogenesis of ovarian endometriosis and may serve as a diagnostic and prognostic biomarker for the disease.

Exosomal microRNAs and long noncoding RNAs: as novel biomarkers for endometriosis

Endometriosis is a gynecological inflammatory disorder characterized by the development of endometrial-like cells outside the uterine cavity. This disease is associated with a wide range of clinical presentations, such as debilitating pelvic pain and infertility issues. Endometriosis diagnosis is not easily discovered by ultrasound or clinical examination. Indeed, difficulties in noninvasive endometriosis diagnosis delay the confirmation and management of the disorder, increase symptoms, and place a significant medical and financial burden on patients. So, identifying specific and sensitive biomarkers for this disease should therefore be a top goal. Exosomes are extracellular vesicles secreted by most cell types. They transport between cells' bioactive molecules such as noncoding RNAs and proteins. MicroRNAs and long noncoding RNAs which are key molecules transferred by exosomes have recently been identified to have a significant role in endometriosis by modulating different proteins and their related genes. As a result, the current review focuses on exosomal micro-and-long noncoding RNAs that are involved in endometriosis disease. Furthermore, major molecular mechanisms linking corresponding RNA molecules to endometriosis development will be briefly discussed to better clarify the potential functions of exosomal noncoding RNAs in the therapy and diagnosis of endometriosis.

Insight into the Potential Mechanisms of Endocrine Disruption by Dietary Phytoestrogens in the Context of the Etiopathogenesis of Endometriosis

Phytoestrogens (PEs) are estrogen-like nonsteroidal compounds derived from plants (e.g., nuts, seeds, fruits, and vegetables) and fungi that are structurally similar to 17β-estradiol. PEs bind to all types of estrogen receptors, including ERα and ERβ receptors, nuclear receptors, and a membrane-bound estrogen receptor known as the G protein-coupled estrogen receptor (GPER). As endocrine-disrupting chemicals (EDCs) with pro- or antiestrogenic properties, PEs can potentially disrupt the hormonal regulation of homeostasis, resulting in developmental and reproductive abnormalities. However, a lack of PEs in the diet does not result in the development of deficiency symptoms. To properly assess the benefits and risks associated with the use of a PE-rich diet, it is necessary to distinguish between endocrine disruption (endocrine-mediated adverse effects) and nonspecific effects on the endocrine system. Endometriosis is an estrogen-dependent disease of unknown etiopathogenesis, in which tissue similar to the lining of the uterus (the endometrium) grows outside of the uterus with subsequent complications being manifested as a result of local inflammatory reactions. Endometriosis affects 10-15% of women of reproductive age and is associated with chronic pelvic pain, dysmenorrhea, dyspareunia, and infertility. In this review, the endocrine-disruptive actions of PEs are reviewed in the context of endometriosis to determine whether a PE-rich diet has a positive or negative effect on the risk and course of endometriosis.

Aberrant epigenetic regulation of estrogen and progesterone signaling at the level of endometrial/endometriotic tissue in the pathomechanism of endometriosis

Endometriosis is a term referring to a condition whereby the endometrial tissue is found outside the uterine cavity. This progressive and debilitating condition affects up to 15% of women of reproductive age. Due to the fact that endometriosis cells may express estrogen receptors (ERα, Erβ, GPER) and progesterone (P4) receptors (PR-A, PR-B), their growth, cyclic proliferation, and breakdown are similar to the processes occurring in the endometrium. The underlying etiology and pathogenesis of endometriosis are still not fully explained. The retrograde transport of viable menstrual endometrial cells with the retained ability to attach within the pelvic cavity, proliferate, differentiate and invade into the surrounding tissue explains the most widely accepted implantation theory. Endometrial stromal cells (EnSCs) with clonogenic potential constitute the most abundant population of cells within endometrium that resemble the properties of mesenchymal stem cells (MSCs). Accordingly, formation of the endometriotic foci in endometriosis may be due to a kind of EnSCs dysfunction. Increasing evidence indicates the underestimated role of epigenetic mechanisms in the pathogenesis of endometriosis. Hormone-mediated epigenetic modifications of the genome in EnSCs or even MSCs were attributed an important role in the etiopathogenesis of endometriosis. The roles of excess estrogen exposure and P4 resistance were also found to be crucial in the development of epigenetic homeostasis failure. Therefore, the aim of this review was to consolidate the current knowledge regarding the epigenetic background of EnSCs and MSCs and the changed properties due to estrogen/P4 imbalances in the context of the etiopathogenesis of endometriosis.

Epigenetics, endometriosis and sex steroid receptors: An update on the epigenetic regulatory mechanisms of estrogen and progesterone receptors in patients with endometriosis

Endometriosis is a benign gynecological disease affecting ∼10% of reproductive-aged women and is defined as the presence of endometrial glands and stroma outside the uterine cavity. Endometriosis can cause a variety of health problems, from pelvic discomfort to catamenial pneumothorax, but it's mainly linked with severe and chronic pelvic pain, dysmenorrhea, and deep dyspareunia, as well as reproductive issues. The pathogenesis of endometriosis involves an endocrine dysfunction, with estrogen dependency and progesterone resistance, and inflammatory mechanism activation, together with impaired cell proliferation and neuroangiogenesis. The present chapter aims to discuss the main epigenetic mechanisms related to estrogen receptors (ERs) and progesterone receptors (PRs) in patients with endometriosis. There are numerous epigenetic mechanisms participating in endometriosis, regulating the expression of the genes encoding these receptors both indirectly, through the regulation of transcription factors, and directly, through DNA methylation, histone modifications, micro RNAs and long noncoding RNAs. This represents an open field of investigation, which may lead to important clinical implications such as the development of epigenetic drugs for the treatment of endometriosis and the identification of specific and early biomarkers for the disease.

The Role of Long Non-Coding RNAs in Endometriosis

Endometriosis is a chronic gynecological disorder affecting the quality of life and fertility of many women around the world. Heterogeneous and non-specific symptoms may lead to a delay in diagnosis, with treatment options limited to surgery and hormonal therapy. Hence, there is a need to better understand the pathogenesis of the disease to improve diagnosis and treatment. Long non-coding RNAs (lncRNAs) have been increasingly shown to be involved in gene regulation but remain relatively under investigated in endometriosis. Mutational and transcriptomic studies have implicated lncRNAs in the pathogenesis of endometriosis. Single-nucleotide polymorphisms (SNPs) in lncRNAs or their regulatory regions have been associated with endometriosis. Genome-wide transcriptomic studies have identified lncRNAs that show deregulated expression in endometriosis, some of which have been subjected to further experiments, which support a role in endometriosis. Mechanistic studies indicate that lncRNAs may regulate genes involved in endometriosis by acting as a molecular sponge for miRNAs, by directly targeting regulatory elements via interactions with chromatin or transcription factors or by affecting signaling pathways. Future studies should concentrate on determining the role of uncharacterized lncRNAs revealed by endometriosis transcriptome studies and the relevance of lncRNAs implicated in the disease by in vitro and animal model studies.

New Therapeutics in Endometriosis: A Review of Hormonal, Non-Hormonal, and Non-Coding RNA Treatments

Endometriosis is defined as endometrial-like tissue outside the uterine cavity. It is a chronic inflammatory estrogen-dependent disease causing pain and infertility in about 10% of women of reproductive age. Treatment nowadays consists of medical and surgical therapies. Medical treatments are based on painkillers and hormonal treatments. To date, none of the medical treatments have been able to cure the disease and symptoms recur as soon as the medication is stopped. The development of new biomedical targets, aiming at the cellular and molecular mechanisms responsible for endometriosis, is needed. This article summarizes the most recent medications under investigation in endometriosis treatment with an emphasis on non-coding RNAs that are emerging as key players in several human diseases, including cancer and endometriosis.

Estrogen- and Progesterone (P4)-Mediated Epigenetic Modifications of Endometrial Stromal Cells (EnSCs) and/or Mesenchymal Stem/Stromal Cells (MSCs) in the Etiopathogenesis of Endometriosis

Endometriosis is a common chronic inflammatory condition in which endometrial tissue appears outside the uterine cavity. Because ectopic endometriosis cells express both estrogen and progesterone (P4) receptors, they grow and undergo cyclic proliferation and breakdown similar to the endometrium. This debilitating gynecological disease affects up to 15% of reproductive aged women. Despite many years of research, the etiopathogenesis of endometrial lesions remains unclear. Retrograde transport of the viable menstrual endometrial cells with retained ability for attachment within the pelvic cavity, proliferation, differentiation and subsequent invasion into the surrounding tissue constitutes the rationale for widely accepted implantation theory. Accordingly, the most abundant cells in the endometrium are endometrial stromal cells (EnSCs). These cells constitute a particular population with clonogenic activity that resembles properties of mesenchymal stem/stromal cells (MSCs). Thus, a significant role of stem cell-based dysfunction in formation of the initial endometrial lesions is suspected. There is increasing evidence that the role of epigenetic mechanisms and processes in endometriosis have been underestimated. The importance of excess estrogen exposure and P4 resistance in epigenetic homeostasis failure in the endometrial/endometriotic tissue are crucial. Epigenetic alterations regarding transcription factors of estrogen and P4 signaling pathways in MSCs are robust in endometriotic tissue. Thus, perspectives for the future may include MSCs and EnSCs as the targets of epigenetic therapies in the prevention and treatment of endometriosis. Here, we reviewed the current known changes in the epigenetic background of EnSCs and MSCs due to estrogen/P4 imbalances in the context of etiopathogenesis of endometriosis. Graphical Abstract.

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.

Small RNA sequencing reveals distinct nuclear microRNAs in pig granulosa cells during ovarian follicle growth

Nuclear small RNAs have emerged as an important subset of non-coding RNA species that are capable of regulating gene expression. A type of small RNA, microRNA (miRNA) have been shown to regulate development of the ovarian follicle via canonical targeting and translational repression. Little has been done to study these molecules at a subcellular level. Using cell fractionation and high throughput sequencing, we surveyed cytoplasmic and nuclear small RNA found in the granulosa cells of the pig ovarian antral preovulatory follicle. Bioinformatics analysis revealed a diverse network of small RNA that differ in their subcellular distribution and implied function. We identified predicted genomic DNA binding sites for nucleus-enriched miRNAs that may potentially be involved in transcriptional regulation. The small nucleolar RNA (snoRNA) SNORA73, known to be involved in steroid synthesis, was also found to be highly enriched in the cytoplasm, suggesting a role for snoRNA species in ovarian function. Taken together, these data provide an important resource to study the small RNAome in ovarian follicles and how they may impact fertility.

Emerging Roles of Long Non-coding RNAs in Uterine Leiomyoma Pathogenesis: a Review

Uterine leiomyoma (UL), as the most prevalent type of women's health disorders, is a benign tumor that originates from the smooth muscle cell layer of the uterus. A great number of associated complications are observed including infertility, miscarriage, bleeding, pain, dysmenorrhea, menorrhagia, and dyspareunia. Although the etiology of UL is largely undefined, environmental and genetic factors are witnessed to engage in the UL development. As long non-coding RNAs (lncRNAs) are involved in various types of cellular functions, in recent years, a great deal of attention has been drawn to them and their possible roles in UL pathogenesis. Moreover, they have illustrated their potential to be promising candidates for UL treatment. In this review paper, firstly, an overview of UL pathogenesis is presented. Then, the regulation of lncRNAs in UL and their possible mechanisms in cancer development are reviewed. Eventually, therapeutic approaches targeting lncRNAs in various cancers and UL are explored.

Kiwi Root Extract Inhibits the Development of Endometriosis in Mice by Downregulating Inflammatory Factors

Purpose

To determine whether the kiwi root extract inhibits the development of endometriosis in mice by suppressing inflammatory factors.

Materials and Methods

The mouse model of endometriosis was induced by surgery after which the mice were continuously injected with the drug for 14 days. On the 14^th day, the mice were sacrificed, and the peritoneal fluid was obtained for enzyme-linked immunosorbent assay. Endometrial ectopic tissue was weighed and analyzed by tissue immunochemistry, RT-PCR, western blotting, and gelatin zymography experiment.

Results

Kiwi root extract significantly reduced endometriotic lesion volume and downregulated the proinflammatory cytokines IL-6, IL-8, IL-1β, and TNF-α, as well as the angiogenic factor VEGF-A. It also inhibited the mRNA and protein expression of COX-1 and COX-2, IL-6, TGF-β1, EP₂ receptor, and ER-β in endometriotic lesions but did not affect the expression of MMP-9 and MMP-2.

Conclusions

Kiwi root extract could significantly inhibit the growth of surgery-induced endometriosis in mice. Our results suggest that the kiwi root extract may inhibit the development and progression of ectopic endometrium through disruption of neovascularization and reducing inflammation, which may be beneficial in treating this common gynecological disease.

Steroid receptor RNA activator inhibits the migration, invasion and stemness characteristics of renal cell carcinoma cells

Renal cell carcinoma (RCC) has a high mortality rate among urological malignancies, and its underlying mechanisms remain unclear. Steroid receptor RNA coactivator (SRA) belongs to the long non-coding RNAs (lncRNAs) and has been demonstrated to be closely related to various types of cancer. In the present study, the decreased expression level of SRA was first confirmed in RCC tissues and cell lines by RT-qPCR. Using knockdown or overexpression systems, it was then found that SRA inhibited the proliferation of RCC cell lines and promoted their apoptosis. In addition, SRA suppressed the migration and invasion, and altered EMT-related markers in RCC cells. More importantly, it was demonstrated that SRA reduced percentage of CD44⁺/CD24⁻ cells and the sphere-forming efficiency. SRA also attenuated the expression levels of CD44, SOX-2, ABCG2 and OCT-4, which are all associated with cancer cell stemness characteristics. Although SRA increased the phosphorylation of extracellular-regulated protein kinase (ERK), the ERK1/2 pathway could not further interfere with the alteration of EMT-related markers mediated by SRA. Notably, the ERK inhibitor, PD98059, abolished ERK1/2 phosphorylation, whereas it did not exert any marked effects on cell proliferation and EMT-related markers mediated by SRA. Taken together, the findings of the present study indicate that SRA is an important molecule that inhibits the migration, invasion and stem cell characteristics of RCC cells; the ERK signaling pathway may not be involved in this process.

Targeting steroid receptor RNA activator (SRA), a long non-coding RNA, enhances melanogenesis through activation of TRP1 and inhibition of p38 phosphorylation

Abnormal skin melanin homeostasis results in refractory pigmentary diseases. Melanogenesis is influenced by gene regulation, ultraviolet radiation, and host epigenetic responses. Steroid receptor RNA activator (SRA), a long noncoding RNA, is known to regulate steroidogenesis and tumorigenesis. However, how SRA contributes to melanogenesis remains unknown. Using RNA interference against SRA in B16 and A375 melanoma cells, we observed increased pigmentation and increased expression of TRP1 and TRP2 at transcriptional and translational levels only in B16 cells. The constitutive phosphorylation of p38 in B16-shCtrl cells was inhibited in cells with knocked down SRAi. Moreover, the melanin content of control B16 cells was increased by SB202190, a p38 inhibitor. Furthermore, reduced p38 phosphorylation, enhanced TRP1 expression, and hypermelanosis were observed in A375 cells with RNA interference. These results indicate that SRA-p38-TRP1 axis has a regulatory role in melanin homeostasis and that SRA might be a potential therapeutic target for treating pigmentary diseases.

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.

Perspectives on the Role of Non-Coding RNAs in the Regulation of Expression and Function of the Estrogen Receptor

Estrogen receptors (ERs) comprise several nuclear and membrane-bound receptors with different tissue-specific functions. ERα and ERβ are two nuclear members of this family, whereas G protein-coupled estrogen receptor (GPER), ER-X, and Gq-coupled membrane estrogen receptor (Gq-mER) are membrane-bound G protein-coupled proteins. ERα participates in the development and function of several body organs such as the reproductive system, brain, heart and musculoskeletal systems. ERβ has a highly tissue-specific expression pattern, particularly in the female reproductive system, and exerts tumor-suppressive roles in some tissues. Recent studies have revealed functional links between both nuclear and membrane-bound ERs and non-coding RNAs. Several oncogenic lncRNAs and miRNAs have been shown to exert their effects through the modulation of the expression of ERs. Moreover, treatment with estradiol has been shown to alter the malignant behavior of cancer cells through functional axes composed of non-coding RNAs and ERs. The interaction between ERs and non-coding RNAs has functional relevance in several human pathologies associated with estrogen regulation, such as cancers, intervertebral disc degeneration, coronary heart disease and diabetes. In the current review, we summarize scientific literature on the role of miRNAs and lncRNAs on ER-associated signaling and related disorders.

Epigenetics of Estrogen and Progesterone Receptors in Endometriosis

Endometriosis is an estrogen-dependent inflammatory gynecological disease. Increased estrogen activity and progesterone resistance are the main hormonal substrate of this disease and are associated with inflammatory response and debilitating symptoms, including pain and infertility. Estrogens and progesterone act via their specific nuclear receptors. The regulation of receptor expression by epigenetics maybe a critical factor for endometriosis. The present review aims to discuss the epigenetic mechanisms related to the expression of estrogen receptors (ERs) and progesterone receptors (PRs) in patients with endometriosis, including two classic epigenetic mechanisms: DNA methylation and histone modification, and, other non-classic mechanisms: miRNAs and lncRNA. Several in vitro and in vivo studies support the key role of epigenetics in the regulation of the expression of ERs and PRs, which may provide new molecules and targets for the diagnosis and treatment of endometriosis.

LncRNA-SRA1 Suppresses Osteosarcoma Cell Proliferation While Promoting Cell Apoptosis

Objective:

Osteosarcoma is a common malignant bone tumor that is frequently found in the long bones of children and adolescents. The aim of this study is to examine long noncoding RNA-steroid receptor RNA activator 1 expression in osteosarcoma to explore the biological function of long noncoding RNA steroid receptor RNA activator 1 on proliferation, migration, and invasion along with apoptosis and its regulatory mechanism, which would facilitate the early diagnosis and targeted therapy of osteosarcoma.

Methods:

First, microarray analysis was applied to determine the expression of long noncoding RNAs in osteosarcoma tissues and paired normal tissues. Then, quantitative real-time polymerase chain reaction was utilized to validate microarray findings. Next, osteosarcoma cancerous cell lines SJSA-1 and U2OS were transfected with pcDNA3.1-SRA1 or pCMV-sh-SRA1 to increase or decrease steroid receptor RNA activator 1 expression levels, and microRNA-208a inhibitors, mimic to investigate the effects of microRNA-208a on osteosarcoma as well as the regulatory relation between long noncoding RNA steroid receptor RNA activator 1 and microRNA-208a. Cell proliferation was evaluated through Cell Counting Kit-8 and colony formation assays. Flow cytometry analysis was conducted to evaluate the apoptosis ratio. The migration and invasion abilities were measured using wound-healing and transwell assays.

Results:

Long noncoding RNA-steroid receptor RNA activator 1 expression was downregulated in osteosarcoma tissues and cells compared with that in corresponding normal tissues, whereas microRNA-208a expression was upregulated in osteosarcoma tissues. Moreover, the restoration of long noncoding RNA steroid receptor RNA activator 1 inhibited cell proliferation, and upregulation of long noncoding RNA steroid receptor RNA activator 1 restrained cell migration and invasion but boosted the apoptosis rate in osteosarcoma cells. In addition, long noncoding RNA steroid receptor RNA activator 1 targeting microRNA-208a was involved in the progression of osteosarcoma. Furthermore, upregulating microRNA-208a exerted similar roles of silencing long noncoding RNA steroid receptor RNA activator 1 in cell apoptosis, proliferation, migration, and invasion, which were reversed by enhancing the expression of long noncoding RNA steroid receptor RNA activator 1.

Conclusions:

In our study, long noncoding RNA steroid receptor RNA activator 1 played an antitumor role in osteosarcoma as it reduced cell migration, invasion, and proliferation, but facilitated cell apoptosis via sponging microRNA-208a, which could be regarded as a potential therapeutic target of osteosarcoma treatment.

LncRNA H19 over-expression inhibited Th17 cell differentiation to relieve endometriosis through miR-342-3p/IER3 pathway

Objective

To investigate the mechanism of LncRNA H19 in Th17 cell differentiation and endometrial stromal cells (ESCs) proliferation in endometriosis (EMS).

Methods

LncRNA H19, miR-342-3p and IER3 expressions were detected by qRT-PCR and western blot. The percentage of Th17 cells/CD4+ T cells was detected by flow cytometry. IL-17 level was measured by ELISA. The interaction of miR-342-3p and IER3 was confirmed by Luciferase reporter assay.

Results

LncRNA H19 and IER3 expressions were down-regulated in mononuclear cells from peritoneal fluid (PFMCs) of patients with EMS or under Th17 differentiation conditions, whereas miR-342-3p expression was up-regulated and the percentage of Th17 cells was increased in PFMCs of patients with EMS or under Th17 differentiation conditions. Over-expression of LncRNA H19 decreased IL-17 level and the percentage of Th17 cells/CD4+ T cells. Besides, we confirmed that miR-342-3p could target to IER3 and negatively regulate IER3 expression. LncRNA H19 over-expression suppressed Th17 differentiation and ESC proliferation through regulating miR-342-3p/IER3. In vivo experiments showed LncRNA H19 over-expression suppressed the growth of Th17 cell differentiation-induced endometriosis-like lesions.

Conclusion

LncRNA H19 was down-regulated in PFMC of patients with EMS or under Th17 polarizing conditions, and LncRNA H19 over-expression suppressed Th17 cell differentiation and ESCs proliferation through miR-342-3p/IER3 pathway.

LncRNA SRA1 may play a role in the uterine leiomyoma tumor growth regarding the MED12 mutation pattern

Background

Uterine leiomyomas (ULMs) are benign uterine tumors that are estrogen-dependent. Recent studies suggest that the abnormal expression of the steroid receptor RNA activator 1 (SRA1) long non-coding RNA (lncRNA) might participate in the mechanisms of tumorigenesis of some hormone-dependent tumors including breast cancer. SRA1 is known to enhance the transcriptional activity of steroid receptors and also promotes steroidogenesis. The level of steroid hormones, such as estrogen and the progesterone, and their receptors play an important role in the development and growth of leiomyoma. The aim of the present study was to determine the expression level of lncRNA SRA1 in ULM tissues considering the MED12 mutation pattern.

Methods

Mutation screening was performed for MED12 exons 1 and 2 and the intronic flanking regions using Sanger sequencing in 60 ULM tissues. Quantitative real-time polymerase chain reaction (qRT-PCRs) was performed in order to estimate the expression of lncRNA SRA1 in leiomyoma samples with and without MED12 gene mutations. The expression results were analyzed by using LinReg and REST software.

Results

Mutations were detected in exon 2 of the MED12 in 28 (46.67%) ULM samples; including, 21 (75%) missense mutations and 7 (25%) in-frame deletions. No mutation was detected in the MED12 exon 1. LncRNA SRA1 was over-expressed in ULM samples without MED12 mutation compared with ULM samples harboring MED12 mutation (Expression ratio=2.5, P-value=0.004).

Conclusion

Present results suggest that lncRNA SRA1 may explain the phenotypic difference observed in the tumor size of ULM samples considering MED12 mutation pattern. Therefore, it serves as a good therapeutic target and provides new insight into understanding the disease molecular mechanism.

Progress in understanding the relationship between long noncoding RNA and endometriosis

Endometriosis is a common gynecological disease. However, the etiology of endometriosis is still unclear, and current theories cannot fully elaborate its specific pathogenesis. Recently, some research has suggested that the occurrence and development of endometriosis may be related to genetics. Long-chain non-coding RNA (lncRNAs) is a kind of non-protein-coding RNA molecule with a length of 200-100,000 bp. With complex biological functions, lncRNAs play an important role in the normal development of individuals and the progression of various diseases, and lncRNAs have become an important field of medical research in recent years. This paper mainly illustrates the research progress on lncRNAs as they relate to endometriosis. We also provide some ideas for exploring the pathogenesis of endometriosis.

Villainous role of estrogen in macrophage-nerve interaction in endometriosis

Endometriosis is a complex and heterogeneous disorder with unknown etiology. Dysregulation of macrophages and innervation are important factors influencing the pathogenesis of endometriosis-associated pain. It is known to be an estrogen-dependent disease, estrogen can promote secretion of chemokines from peripheral nerves, enhancing the recruitment and polarization of macrophages in endometriotic tissue. Macrophages have a role in the expression of multiple nerve growth factors (NGF), which mediates the imbalance of neurogenesis in an estrogen-dependent manner. Under the influence of estrogen, co-existence of macrophages and nerves induces an innovative neuro-immune communication. Persistent stimulation by inflammatory cytokines from macrophages on nociceptors of peripheral nerves aggravates neuroinflammation through the release of inflammatory neurotransmitters. This neuro-immune interaction regulated by estrogen sensitizes peripheral nerves, leading to neuropathic pain in endometriosis. The aim of this review is to highlight the significance of estrogen in the interaction between macrophages and nerve fibers, and to suggest a potentially valuable therapeutic target for endometriosis-associated pain.

New Insights Into the Long Non-coding RNA SRA: Physiological Functions and Mechanisms of Action

Long non-coding RNAs (lncRNA) are emerging as new genetic/epigenetic regulators that can impact almost all physiological functions. Here, we focus on the long non-coding steroid receptor RNA activator (SRA), including new insights into its effects on gene expression, the cell cycle, and differentiation; how these relate to physiology and disease; and the mechanisms underlying these effects. We discuss how SRA acts as an RNA coactivator in nuclear receptor signaling; its effects on steroidogenesis, adipogenesis, and myocyte differentiation; the impact on breast and prostate cancer tumorigenesis; and, finally, its ability to modulate hepatic steatosis through several signaling pathways. Genome-wide analysis reveals that SRA regulates hundreds of target genes in adipocytes and breast cancer cells and binds to thousands of genomic sites in human pluripotent stem cells. Recent studies indicate that SRA acts as a molecular scaffold and forms networks with numerous coregulators and chromatin-modifying regulators in both activating and repressive complexes. We discuss how modifications to SRA's unique stem-loop secondary structure are important for SRA function, and highlight the various SRA isoforms and mutations that have clinical implications. Finally, we discuss the future directions for better understanding the molecular mechanisms of SRA action and how this might lead to new diagnostic and therapeutic approaches.

Upregulation of S100A6 in patients with endometriosis and its role in ectopic endometrial stromal cells

S100 calcium-binding protein A6 (S100A6) is up-regulated in many malignancies and overexpression of S100A6 has been identified associated with proliferation, migration and invasion phenotype in several cancer cells. In the present study, we explored whether S100A6 plays a role in the development of endometriosis. Significantly higher levels of mRNA and protein expression of S100A6 were observed in ectopic endometrial tissues compared to eutopic and normal endometrial tissues. Silencing of S100A6 in ectopic endometrial stromal cells (ESCs) significantly inhibited cell viability, migration and invasion. Moreover, knockdown of S100A6 suppressed p38/MAPK activity in ectopic ESCs, which can be partially attenuated by CacyBP/SIP phosphorylation inhibitor. In conclusion, our results suggest that the abnormal expression of S100A6 may contribute to the pathogenesis of endometriosis and the S100A6/CacyBP/p38 signaling may provide as a promising treatment target.

miR-200c suppresses endometriosis by targeting MALAT1 in vitro and in vivo

BACKGROUND

Endometriosis is a common, benign, and estrogen-dependent disease characterized by pelvic pain and infertility. To date, the pathogenesis of endometriosis remains unclear. Recent studies have demonstrated that noncoding RNAs, including microRNAs and long noncoding RNAs, play important roles in the development of endometriosis.

METHODS

Expression profiling of miRNAs in endometrial tissue was characterized using microarrays. The most differentially expressed miRNAs were confirmed using quantitative reverse transcriptase-polymerase chain reaction analysis in additional ectopic endometrial (n = 27) and normal endometrial (n = 12) tissues. For in-vitro functional studies, 5-ethynyl-2'-deoxyuridine incorporation assay, Transwell assay, and dual-luciferase reporter assay were used to measure the proliferation, migration, and luciferase activity of miR-200c and the predicted targets of miR-200c in primary endometrial stromal cells (HESCs) derived from human endometrial biopsies, respectively. For in-vivo therapeutic interventions, polymeric nanoparticles of polyethylenimine-polyethylene glycol-arginine-glycine-aspartic acid were used for delivery of miR-200c mimic and inhibitor to determine the therapeutic effect of miR-200c in a rat model of endometriosis.

RESULTS

Exogenous overexpression of miR-200c inhibited the proliferation and migration of HESCs, which were mainly regulated by metastasis-associated lung adenocarcinoma transcript 1 (MALAT1). In contrast, inhibition of miR-200c promoted the proliferation and migration of HESCs, while the simultaneous silencing of MALAT1 expression exerted the opposite effects. We demonstrated that expression of MALAT1 in ectopic endometrial specimens was negatively correlated with that of miR-200c and that MALAT1 knockdown increased the level of miR-200c in HESCs. Moreover, the transfection of endometrial stromal cells with the miR-200c mimic or MALAT1 siRNAs decreased the protein levels of mesenchymal markers ZEB1, ZEB2, and N-cadherin and increased the protein levels of the epithelial marker E-cadherin. Furthermore, using a rat endometriosis model, we showed that local delivery of the miR-200c mimic significantly inhibited the growth of ectopic endometriotic lesions.

CONCLUSIONS

The MALAT1/miR-200c sponge may be a potential therapeutic target for endometriosis.

Biological functions and role of CCN1/Cyr61 in embryogenesis and tumorigenesis in the female reproductive system (Review)

Cysteine-rich angiogenic inducer 61 (CCN1/Cyr61) is a prompt response transcription product activated by growth factors. As a member of the CCN family, it mediates cell survival, proliferation, differentiation, migration, adhesion and synthesis of the extracellular matrix by binding directly to the integrins and heparin sulfate proteoglycans or activating multiple signaling transduction pathways. It has previously been demonstrated that CCN1/Cyr61 exhibits an important role in the female reproductive system during embryogenesis and tumorigenesis. However, the functions of CCN1/Cyr61 in the female reproductive system have not been systematically investigated, therefore, the primary aim of the present review is to introduce the role and function of CCN1/Cyr61 in the female reproductive system. The current review presents the molecular structure and biological function of CCN1/Cyr61 and provides detailed data on its expression pattern and contribution to the female reproductive system, including the role in embryogenesis and tumorigenesis.