Expression and clinical significance of estrogen-regulated long non-coding RNAs in estrogen receptor α-positive ovarian cancer progression

Estrogen Biosynthesis and Signal Transduction in Ovarian Disease

Estrogen mainly binds to estrogen receptors (ERs) to regulate menstrual cycles and reproduction. The expression of ERalpha (ERα), ERbeta (ERβ), and G-protein-coupled estrogen receptor (GPER) mRNA could be detected in ovary, suggesting that they play an important role in estrogen signal transduction in ovary. And many studies have revealed that abnormal expression of estrogen and its receptors is closely related to ovarian disease or malignant tumors. With the continuous development and research of animal models, tissue-specific roles of both ERα and ERβ have been demonstrated in animals, which enable people to have a deeper understanding of the potential role of ER in regulating female reproductive diseases. Nevertheless, our current understanding of ERs expression and function in ovarian disease is, however, incomplete. To elucidate the biological mechanism behind ERs in the ovary, this review will focus on the role of ERα and ERβ in polycystic ovary syndrome (PCOS), ovarian cancer and premature ovarian failure (POF) and discuss the major challenges of existing therapies to provide a reference for the treatment of estrogen target tissue ovarian diseases.

Role of estrogen receptors in health and disease

Estrogen receptors (ERs) regulate multiple complex physiological processes in humans. Abnormal ER signaling may result in various disorders, including reproductive system-related disorders (endometriosis, and breast, ovarian, and prostate cancer), bone-related abnormalities, lung cancer, cardiovascular disease, gastrointestinal disease, urogenital tract disease, neurodegenerative disorders, and cutaneous melanoma. ER alpha (ERα), ER beta (ERβ), and novel G-protein-coupled estrogen receptor 1 (GPER1) have been identified as the most prominent ERs. This review provides an overview of ERα, ERβ, and GPER1, as well as their functions in health and disease. Furthermore, the potential clinical applications and challenges are discussed.

The Central Roles of Noncoding RNA in Estrogen-Dependent Female Reproductive System Tumors

The pathogenesis of ovarian and endometrial cancers is closely associated with estrogen-related pathways. These estrogen-dependent tumors seriously threaten the health and quality of life in women. Noncoding RNAs (ncRNAs) are defined as RNAs that do not encode proteins, including microRNAs (miRNAs) and long noncoding RNAs (lncRNAs), both of which have been reported in estrogen-dependent female reproductive system tumors. This review systematically summarizes the role of ncRNAs in estrogen-dependent tumors and common patterns of regulatory mechanisms to explore their future research directions in tumor diagnosis, treatment, and prognosis. This may provide new ideas for the potential application of ncRNAs in estrogen-dependent female reproductive system tumors.

Long non-coding RNA LINC00504 regulates the Warburg effect in ovarian cancer through inhibition of miR-1244

Ovarian cancer (OC) is the most lethal gynecologic malignancy and long non-coding RNAs (lncRNAs) have been acknowledged as important regulators in human OC. This study aimed to investigate the function and underlying mechanisms of LINC00504 in OC. The expression levels of LINC00504 in human OC tissues and cell lines were investigated by qRT-PCR analysis. The OC cell proliferation, and apoptosis were evaluated by MTT assay, colony-formation assay, Caspase-3 activity assay, and nucleosome ELISA assay, respectively. The metabolic shift in OC cells was examined by aerobic glycolysis analysis. Dual-luciferase activity reporter assay and mRNA-miRNA pull-down assay were conducted to validate the interaction between LINC00504 and miR-1244. LINC00504 was upregulated in OC cell lines and specimens. Knockdown of LINC00504 inhibited cell proliferation, enhanced apoptosis, decreased glycolysis-related gene (PKM2, HK2, and PDK1) expression, and altered aerobic glycolysis in OC cells and vice versa. LINC00504 downregulated miR-1244 expression levels by acting as an endogenous sponge of miR-1244. Inhibition of miR-1244 diminished the effects of LINC00504 on OC cells. Our study shows that LINC00504 promotes OC cell progression and stimulates aerobic glycolysis by interacting with miR-1244, which indicates that LINC00504 might act as a promising therapeutic target for OC treatment.

Microarray Profiling and Coexpression Network Analysis of Long Noncoding RNAs in Adipose Tissue of Obesity-T2DM Mouse

OBJECTIVE

The aim of this study was to understand more about long noncoding RNAs (lncRNAs) as potential prediction biomarkers or therapeutic targets for obesity and type 2 diabetes mellitus (T2DM). This study aimed to find more lncRNA candidates related to obesity and T2DM.

METHODS

In this study, a high-fat diet (HFD)-induced obesity-T2DM mouse model was used, and a mRNA and lncRNA expression map was drawn up in adipose tissue by microarray technology. Then Gene Ontology analysis and Kyoto Encyclopedia of Genes and Genomes pathway analysis were performed and revealed that the most associated genes and pathways were metabolism-related ones. The candidate lncRNA expression was further validated in adipose tissue from HFD-induced mice by quantitative real-time polymerase chain reaction analysis.

RESULTS

Transcriptome analyses were performed to show expression profiles of mRNAs and lncRNAs in epididymal adipose tissue in the obesity-T2DM mice. A total of 124 lncRNAs and 1,606 mRNAs were differentially expressed between the chow and HFD groups. Then, an mRNA-lncRNA coexpression network was constructed. Based on a series of analyses, 15 candidate lncRNAs were screened, and their expression was further validated by quantitative real-time polymerase chain reaction analysis.

CONCLUSIONS

The results reveal significant differences between the transcriptomes of the HFD and control groups in adipose tissue that provide clues to the molecular mechanisms of diet-induced metabolic disorders as well as biomarkers of risk for these disorders.

Estrogen-Receptor Expression and Function in Female Reproductive Disease

Estrogen receptors (ER) include ER alpha, ER beta and new membrane receptor G protein-coupled receptor 30 (GPR30). Estrogen receptors are key receptors to maintain ovarian granulosa cell differentiation, follicle and oocyte growth and development, and ovulation function. The abnormal functions of estrogen, its receptors, and estradiol synthesis-related enzymes are closely related to clinical reproductive endocrine diseases, such as polycystic ovary syndrome (PCOS) and endometriosis (EMS). At present, hormone therapy is the main treatment for ovarian-related diseases, and a stable hormone environment is established by regulating ovarian function. In recent years, some estrogen-related drugs have made great progress, such as clomiphene, which is a nonsteroidal antiestrogen drug in clinical application. This article elaborates on the regulatory role of estrogen and its nuclear receptors and membrane receptors in oocyte development, especially female reproductive diseases related to the abnormal expression of estrogen and its receptors. We also highlighted the latest advances of treatment strategy for these diseases and the application of related targeted small molecule drugs in clinical research and treatment, so as to provide reference for the treatment of female reproductive diseases.

LncRNA ADAMTS9-AS2 inhibits cell proliferation and decreases chemoresistance in clear cell renal cell carcinoma via the miR-27a-3p/FOXO1 axis

Accumulating evidence reveals the principal role of long noncoding RNAs in the progression of clear cell renal cell carcinoma (ccRCC). However, little is known about the underlying mechanism of ADAM metallopeptidase with thrombospondin type 1 motif, 9 antisense RNA 2 (ADAMTS9-AS2) in ccRCC. Here, bioinformatics analyses verified ADAMTS9-AS2 is a long noncoding RNA and its high expression was associated with better prognosis of ccRCC. ADAMTS9-AS2 was clearly downregulated in ccRCC clinical samples and cell lines. Clinical data showed low-expressed ADAMTS9-AS2 was correlated with worse overall survival in ccRCC patients. Next, miR-27a-3p was identified as an inhibitory target of ADAMTS9-AS2 by dual-luciferase reporter and RNA immunoprecipitation assays. Both overexpressed ADAMTS9-AS2 and underexpressed miR-27a-3p in ccRCC cell lines led to the inhibition of cell proliferation and the reduction of chemoresistance. Additionally, Forkhead Box Protein O1 (FOXO1) was confirmed as the inhibitory target of miR-27a-3p. Induced by ADAMTS9-AS2 overexpression, cell proliferation and chemoresistance exhibited an obvious reduction, FOXO1 expression showed an evident increase, but all were reversed after miR-27a-3p was simultaneously overexpressed. Collectively, these results suggest ADAMTS9-AS2 inhibits the progression and impairs the chemoresistance of ccRCC via miR-27a-3p-mediated regulation of FOXO1 and may serve as a prognostic biomarker and therapeutic target for ccRCC.

Estrogen receptor β upregulated by lncRNA-H19 to promote cancer stem-like properties in papillary thyroid carcinoma

Estrogen receptor β (ERβ) plays critical roles in thyroid cancer progression. However, its role in thyroid cancer stem cell maintenance remains elusive. Here, we report that ERβ is overexpressed in papillary thyroid cancer stem cells (PTCSCs), whereas ablation of ERβ decreases stemness-related factors expression, diminishes ALDH⁺ cell populations, and suppresses sphere formation ability and tumor growth. Screening estrogen-responsive lncRNAs in PTC spheroid cells, we find that lncRNA-H19 is highly expressed in PTCSCs and PTC tissue specimens, which is correlated with poor overall survival. Mechanistically, estradiol (E2) significantly promotes H19 transcription via ERβ and elevates H19 expression. Silencing of H19 inhibits E2-induced sphere formation ability. Furthermore, H19 acting as a competitive endogenous RNA sequesters miRNA-3126-5p to reciprocally release ERβ expression. ERβ depletion reverses H19-induced stem-like properties upon E2 treatment. Appropriately, ERβ is upregulated in PTC tissue specimens. Notably, aspirin attenuates E2-induced cancer stem-like traits through decreasing both H19 and ERβ expression. Collectively, our findings reveal that ERβ-H19 positive feedback loop has a compelling role in PTCSC maintenance under E2 treatment and provides a potential therapeutic targeting strategy for PTC.

Altered long noncoding RNAs and survival outcomes in ovarian cancer: A systematic review and meta-analysis (PRISMA Compliant)

BACKGROUND

Previous studies investigating the association between altered long noncoding RNAs (lncRNAs) and survival outcomes in ovarian cancer have obtained controversial results. To comprehensively evaluate the association, we conducted a systematic review and meta-analysis of the studies published on the subject.

METHODS

We performed a systematic search using the databases of the Cochrane Central Register of Controlled Trials, PubMed, and Embase to find all relevant articles from inception to May 7, 2017. Studies that evaluated the association between 1 specific lncRNA and survival outcomes in ovarian cancer were included. Pooled hazard ratios (HRs) and 95% confidence intervals (95% CIs) for overall survival, progression-free survival, and disease-free survival were calculated with a fixed-effects or random-effects model.

RESULTS

A total of 15 studies involving 1333 patients with ovarian cancer were included in this meta-analysis. Altered lncRNAs were associated with decreased overall survival (HR: 2.29, 95% CI: 1.92-2.75) without heterogeneity (I = 0.0%) in ovarian cancer. Altered lncRNAs were also associated with decreased progression-free survival (HR: 2.77, 95% CI: 1.00-7.62, I = 76.6%) and disease-free survival (HR: 2.59, 95% CI: 0.89-7.57, I = 62.9%) in ovarian cancer.

CONCLUSION

Our results supported the strong prognostic value of altered lncRNAs in ovarian cancer. Further large-scale studies should be carried out to verify the clinical applications of altered lncRNAs in the prognosis assessment of ovarian cancer.

Emerging roles of long non-coding RNAs in the toxicology of environmental chemicals

Environmental chemicals (ECs) are drawing great attention to their effects on health and their toxicological mechanisms are being investigated. Long non-coding RNA (lncRNA) is a class of RNA with more than 200 nucleotides and does not have protein coding potential. Recently, it is emerging as a star molecule that participates in a wide range of physiological and pathological processes. It has been reported to be abnormally expressed in diseases. As an epigenetic factor, lncRNAs play an important role in the response of organisms to environmental stress. Their roles in the toxicity of ECs are being identified. Altered expression profiles of lncRNAs have been explored after exposure to ECs. Various kinds of ECs are reported to disturb the expression of lncRNAs in vitro and in vivo. Then, dysregulated lncRNAs can affect the expression of target genes directly or indirectly via regulating the level of microRNAs. The network among lncRNAs, microRNAs and mRNAs can initiate or impede specific signaling pathway and lead to adverse outcome upon exposure to ECs. Recovery of the lncRNAs level by overexpression or knockdown technology diminished the effect induced by ECs. In the review, biological roles of lncRNAs are depicted. The lncRNAs involved in the toxicology are summarized. Types of ECs that have been reported to affect the expression of lncRNAs are categorized. The interaction between various types of ECs and lncRNAs is discussed.

Long non-coding RNAs in ovarian cancer

Long non-coding RNAs (lncRNAs) refer to functional cellular RNAs molecules longer than 200 nucleotides in length. Unlike microRNAs, which have been widely studied, little is known about the enigmatic role of lncRNAs. However, lncRNAs have motivated extensively attention in the past few years and are emerging as potentially important regulators in pathological processes, including in cancer. We now understand that lncRNAs play role in cancer through their interactions with DNA, protein, and RNA in many instances. Moreover, accumulating evidence has recognized that large classes of lncRNAs are functional for ovarian cancer. Nevertheless, the biological phenomena and molecular mechanisms of lncRNAs in ovarian cancer remain to be better identified. In this review, we outline the dysregulated expression of lncRNAs and their potential clinical implications in ovarian cancer, with a particular emphasis on discussing the well characterized mechanisms underlying lncRNAs in ovarian cancer.

Genome-wide screening differential long non-coding RNAs expression profiles discloses its roles involved in OHSS development

OBJECTIVE

To screen differentially expressed lncRNAs involved in OHSS. OHSS is defined as ovarian hyperstimulation syndrome. It is characterized as enlarged ovary and increased vascular permeability.

DESIGN

Case-control study.

SETTING

University-affiliated hospital.

PATIENT(S)

Patients with OHSS high risk (n = 30) and low risk (n = 30) were included in this study.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

LncRNAs from women with OHSS high risk and low risk were used for high-throughput sequencing profiling. The eight most differentially expressed lncRNAs in granulosa cells were validated by semi-quantitative reverse transcription-polymerase chain reaction analysis.

RESULT(S)

A total of 23,815 lncRNAs were detected and 482 were differentially expressed (fold-change ≥2; p < 0.05, FDR value < 0.001), of which 205 were upregulated and 277 were downregulated. Lnc-SEC16B.1-6, lnc-SNURF-13, lnc-LGR6-6, and lnc-H2AFY2-2 were up-regulated, while lnc-BRD2-2, lnc-HSPA6-2, and lnc-CLIC6-5 were downregulated significantly in granulosa cells. These results were confirmed by qRT-PCR. KEGG pathways and Gene Ontology enrichment analysis revealed that several biological processes were significantly associated. Meanwhile, the lncRNA/miRNA interaction network was established according to ceRNA network model.

CONCLUSION(S)

Comprehensive expression screening identified eight novel lncRNAs associated with risk factors of OHSS process. Although it is unclear how these altered lncRNAs regulate the process of OHSS, our findings suggest these lncRNAs may be novel players in OHSS development.

Role of lncRNAs in ovarian cancer: defining new biomarkers for therapeutic purposes

Long noncoding RNAs (lncRNAs) are a class of noncoding RNA, involved in regulation of diverse physiological and pathological processes. Ovarian cancer is the leading cause of death among all gynecological malignancies in the world and its underlying mechanism is still unclear. LncRNAs exhibit multiple biological functions in various stages of ovarian cancer development. We will discuss and summarize the new and important lncRNAs and their involvement in disease, which might represent promising therapeutic targets. Therapeutic intervention based on silencing or functional inhibition of target lncRNAs will be beneficial for ovarian cancer patients.

Endometriosis Malignant Transformation: Epigenetics as a Probable Mechanism in Ovarian Tumorigenesis

Endometriosis, defined as the presence of ectopic endometrial glands and stroma outside the uterine cavity, is a chronic, hormone-dependent gynecologic disease affecting millions of women across the world, with symptoms including chronic pelvic pain, dysmenorrhea, dyspareunia, dysuria, and subfertility. In addition, there is well-established evidence that, although endometriosis is considered benign, it is associated with an increased risk of malignant transformation, with the involvement of various mechanisms of development. More and more evidence reveals an important contribution of epigenetic modification not only in endometriosis but also in mechanisms of endometriosis malignant transformation, including DNA methylation and demethylation, histone modifications, and miRNA aberrant expressions. In this present review, we mainly summarize the research progress about the current knowledge regarding the epigenetic modifications of the relations between endometriosis malignant transformation and ovarian cancer in an effort to identify some risk factors probably associated with ectopic endometrium transformation.

Differential microRNA expression profiling in primary tumors and matched liver metastasis of patients with colorectal cancer

Background

Liver metastasis is common in patients with colorectal cancer (CRC), and is correlated with poor outcome. MicroRNAs (miRNAs) are small non-coding RNAs involved in cancer development and progression, but their role in CRC liver metastasis has not been extensively investigated.

Results

Thirteen miRNAs were deregulated in pCRCs compared to their matched liver metastases. Seventeen miRNAs were chosen for validation, which confirmed significantly reduced expression of miR-99b-5p, miR-377 and miR-200c and increased expression of miR-196b-5p in the tissue of liver metastasis. Furthermore, miR-200c and miR-196b-5p were positively correlated with shorter overall survival in pCRC patients with liver metastasis.

Materials and Methods

Firstly, affymetrix microarrays involving 1036 miRNAs were performed in two pairs of primary CRCs (pCRCs) and their matched liver metastases. Secondly, validation of the results was carried out on an independent cohort of 48 pairs of pCRCs and matched liver metastases using quantitative real-time polymerase chain reaction assay.

Conclusions

We discovered a pCRC liver metastasis-specific miRNA panel including miR-377, miR-99b-5p, miR-200c and miR-196b-5p through intensive validation. These miRNAs may function as prognostic factors in patients with metastatic CRC.

Comprehensive analysis of lncRNA expression profiles reveals a novel lncRNA signature to discriminate nonequivalent outcomes in patients with ovarian cancer

There is growing evidence of dysregulated long non-coding RNAs (lncRNAs) serving as potential biomarkers for cancer prognosis. However, systematic efforts of searching for an expression-based lncRNA signature for prognosis prediction in ovarian cancer (OvCa) have not been made yet. Here, we performed comprehensive analysis for lncRNA expression profiles and clinical data of 544 OvCa patients from The Cancer Genome Atlas (TCGA), and identified an eight-lncRNA signature with ability to classify patients of the training cohort into high-risk group showing poor outcome and low-risk group showing significantly improved outcome, which was further validated in the validation cohort and entire TCGA cohort. Multivariate Cox regression analysis and stratified analysis demonstrated that the prognostic value of this signature was independent of other clinicopathological factors. Associating the outcome prediction with BRCA1 and/or BRCA2 mutation revealed a superior prognosis performance both in BRCA1/2-mutated and BRCA1/2 wild-type tumors. Finally, a significantly correlation was found between the lncRNA signature and the complete response rate of chemotherapy, suggesting that this eight-lncRNA signature may be a measure to predict chemotherapy response and identify platinum-resistant patients who might benefit from other more efficacious therapies. With further prospective validation, this eight-lncRNA signature may have important implications for outcome prediction and therapy decisions.

'Lnc'-ing Wnt in female reproductive cancers: therapeutic potential of long non-coding RNAs in Wnt signalling

Recent discoveries in the non-coding genome have challenged the original central dogma of molecular biology, as non-coding RNAs and related processes have been found to be important in regulating gene expression. MicroRNAs and long non-coding RNAs (lncRNAs) are among those that have gained attention recently in human diseases, including cancer, with the involvement of many more non-coding RNAs (ncRNAs) waiting to be discovered. ncRNAs are a group of ribonucleic acids transcribed from regions of the human genome, which do not become translated into proteins, despite having essential roles in cellular physiology. Deregulation of ncRNA expression and function has been observed in cancer pathogenesis. Recently, the roles of a group of ncRNA known as lncRNA have gained attention in cancer, with increasing reports of their oncogenic involvement. Female reproductive cancers remain a leading cause of death in the female population, accounting for almost a third of all female cancer deaths in 2016. The Wnt signalling pathway is one of the most important oncogenic signalling pathways which is hyperactivated in cancers, including female reproductive cancers. The extension of ncRNA research into their mechanistic roles in human cancers has also led to novel reported roles of ncRNAs in the Wnt pathway and Wnt-mediated oncogenesis. This review aims to provide a critical summary of the respective roles and cellular functions of Wnt-associated lncRNAs in female reproductive cancers and explores the potential of circulating cell-free lncRNAs as diagnostic markers and lncRNAs as therapeutic targets.

LINKED ARTICLES

This article is part of a themed section on WNT Signalling: Mechanisms and Therapeutic Opportunities. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v174.24/issuetoc.

Genome-wide study of ER-regulated lncRNAs shows AP000439.3 may function as a key regulator of cell cycle in breast cancer

Estrogen receptor (ER) plays important roles in cell growth, development and tumorigenesis. Although ER-regulated genes have been extensively investigated, little is known about roles of ER-regulated lncRNAs in breast cancer. Here, we conducted genome-wide study of ER-regulated lncRNAs by using RNA-seq, ChIP-seq and TCGA data. A total of identified 114 ER-regulated lncRNAs were identified, many of them were overexpressed in ER+ breast cancer and co-expressed with some key regulators. Silencing one of most prominent lncRNA, AP000439.3, resulted in inhibition of cell cycle progression and proliferation. Further study revealed AP000439.3 can regulate expression of CCND1 through enhancing estrogen receptor induction of CCND1. This finding revealed lncRNAs may serve as important effectors of ER in regulation of gene expression and cell phenotype in breast cancer.

Transcriptome analysis reveals dysregulated long non-coding RNAs and mRNAs associated with extrahepatic cholangiocarcinoma progression

The incidence of extrahepatic cholangiocarcinoma (ECC) is the highest of all the cholangiocarcinoma cases. However, the molecular mechanism of ECC genesis and progression remains unclear. Long non-coding RNAs (lncRNAs) have been revealed to perform critical regulatory roles in cancer biology. In order to understand lncRNA expression patterns and their potential function in ECC, a transcriptome analysis of lncRNA and mRNA expression was performed in ECC and paired adjacent non-cancerous tissues using Agilent human lncRNA + mRNA arrayV4.0 (4×180 K format). It was identified that 268 lncRNAs and 459 mRNAs were differentially expressed in ECC. Among these, 78 lncRNAs and 66 mRNAs were upregulated >2-fold compared with adjacent non-cancerous tissues, and 190 lncRNAs and 393 mRNAs were downregulated in the ECC samples. Differences in lncRNA expression between ECC and paired adjacent non-cancerous tissues were confirmed using reverse transcription-quantitative polymerase chain reactionas proof of principle. Functional analysis of co-expressed mRNAs with lncRNAs indicated that these dysregulated lncRNAsmay be involved in known ECC-associated biological processes and pathways. The present findings indicated that mRNAs and lncRNAs perform important roles in the development and progression of ECC. The present findings may lay the foundation for future efforts to understand the role of lncRNAs and develop novel biomarkers in ECC.

Prognostic value of abnormally expressed lncRNAs in ovarian carcinoma: a systematic review and meta-analysis

Ovarian cancer (OC) is the most deadly gynecological cancer and it is urgently needed to find a new marker for the progress of OC. Many long noncoding RNAs (lncRNAs) have been reported to be aberrantly expressed in ovarian carcinoma, and may serve as prognostic markers. Therefore, we conducted this meta-analysis to gain a better understanding of the prognostic value of lncRNAs in patients with varian carcinoma. We systematically searched PubMed, EMBASE, and Web of Science. A total of 13 eligible studies, including 10 on clinicopathological features, 13 on prognosis were identified. Pooled hazard ratios (HRs) or odds ratios (OR) and 95% confidence intervals (95% CIs) were calculated using random- or fixed-effects models. Our results revealed that the increased expressions of 8 lncRNAs were associated with poor prognosis and the decreased expressions of 5 lncRNAs were related to poor prognosis in ovarian carcinoma. High HOTAIR expression was associated with shorter overall survival in ovarian cancer (pooled HR: 2.05, 95% CI: 1.51-2.77, P < 0.001). In conclusion, our meta-analysis suggested that LncRNAs could function as potential prognostic markers for ovarian cancer patients and high expression HOTAIR was associated with shorter overall survival in ovarian cancer.

Potential Use of Antiapoptotic Proteins and Noncoding RNAs for Efficient In Vitro Follicular Maturation and Ovarian Bioengineering

In vitro culture of ovarian follicles is a promising bioengineering technique for preserving fecundity in reproductive-aged female by providing fertilizable oocytes. Successful clinical application should be preceded by developing the protocols that can efficiently overcome follicular cell apoptosis since the apoptosis is a critical phenomenon in in vivo folliculogenesis and in in vitro follicular maturation. Numerous prosurvival and antiapoptotic molecules, including follicular developmental regulators, have been reported to be involved in the intraovarian apoptosis. The authors searched literature and analyzed the current knowledge of these proteins and noncoding RNAs, and their antiapoptotic roles in the dynamics of follicular development in vivo and in vitro. Two-dimensional (2D) culture method has widely been used, however, with recent emergence of various biomaterials, three-dimensional (3D) culture is also considered a proper environment for maintenance of solid structure of ovarian follicles. The identification of candidate paracrine and endocrine intracellular effectors that are responsible for the coordination occurring between oocyte, granulosa, and theca cells during follicular development was explored in this review, to assess the possibility of their use as antiapoptotic factors in establishing more efficacious 2D or 3D in vitro follicular microenvironment. The retrieved information will provide an inventory and the insight for defining more sophisticated culture conditions that are essential for functional artificial ovarian bioengineering.

The lncRNA landscape of breast cancer reveals a role for DSCAM-AS1 in breast cancer progression

Molecular classification of cancers into subtypes has resulted in an advance in our understanding of tumour biology and treatment response across multiple tumour types. However, to date, cancer profiling has largely focused on protein-coding genes, which comprise <1% of the genome. Here we leverage a compendium of 58,648 long noncoding RNAs (lncRNAs) to subtype 947 breast cancer samples. We show that lncRNA-based profiling categorizes breast tumours by their known molecular subtypes in breast cancer. We identify a cohort of breast cancer-associated and oestrogen-regulated lncRNAs, and investigate the role of the top prioritized oestrogen receptor (ER)-regulated lncRNA, DSCAM-AS1. We demonstrate that DSCAM-AS1 mediates tumour progression and tamoxifen resistance and identify hnRNPL as an interacting protein involved in the mechanism of DSCAM-AS1 action. By highlighting the role of DSCAM-AS1 in breast cancer biology and treatment resistance, this study provides insight into the potential clinical implications of lncRNAs in breast cancer.

LncRNAs have been associated with cancer. Here, the authors carry out a systematic review of lncRNAs in breast cancer and show that DSCAM-AS1 is highly expressed in oestrogen receptor positive tumours and enhances cancer through an interaction with hnRNPL; and is also associated with tamoxifen resistance.

The Role of Long Non-Coding RNAs in Ovarian Cancer

Background:

Mesenchymal stem cells (MSCs) are important candidates for MSC-based cellular therapy. Current paradigm states that MSCs support local progenitor cells in damaged tissue through paracrine signaling. Therefore, the study of paracrine effects and secretome of MSCs could lead to the appreciation of mechanisms and molecules associated with the therapeutic effects of these cells. This study analyzed anti-inflammatory and immune-modulatory effects of MSC secretomes derived from embryonic stem cells (ESCs) and bone marrow cells after hypoxia and normoxia preconditioning.

Methods:

ESCs differentiated into MSCs and characterized by flow cytometry as well as by differentiation into adipocytes and osteoblasts. The experimental groups were consisted of individual groups of ESC-MSCs and BM-MSCs (bone marrow-derived mesenchymal stromal cells), which were preconditioned with either hypoxia or normoxia for 24, 48 and 72 h. After collecting the cell-free medium from each treatment, secretomes were concentrated by centrifugal filters. Using a peripheral blood mononuclear cell (PBMC) assay and ELISA, IL-10 concentration in PBMCs was evaluated after their incubation with different secretomes from preconditioned and non-preconditioned MSCs.

Results:

A significant difference was observed between ESC-MSC normoxia and ESC-MSC hypoxia in IL-10 concentration, and normoxia secretomes increased IL-10 secretion from PBMCs. Moreover, the strongest IL-10 secretion from PBMCs could be detected after the stimulation by ESC-MSC conditioned secretomes, but not BM-MSC conditioned medium.

Conclusions:

Human hypoxia preconditioned ESC-MSC secretome indicated stronger immune-modulatory effects compared to BM-MSC conditioned medium. It could be suggested that induced MSCs confer less immune-modulatory effects but produce more inflammatory molecules such as tumor necrosis factor α, which needs further investigation.

Aberrant expression of long noncoding RNAs in cumulus cells isolated from PCOS patients

PURPOSE

To describe the long noncoding RNA (lncRNA) profiles in cumulus cells isolated from polycystic ovary syndrome (PCOS) patients by employing a microarray and in-depth bioinformatics analysis. This information will help us understand the occurrence and development of PCOS.

METHODS

In this study, we used a microarray to describe lncRNA profiles in cumulus cells isolated from ten patients (five PCOS and five normal women). Several differentially expressed lncRNAs were chosen to validate the microarray results by quantitative RT-PCR (qRT-PCR). Then, the differentially expressed lncRNAs were classified into three subgroups (HOX loci lncRNA, enhancer-like lncRNA, and lincRNA) to deduce their potential features. Furthermore, a lncRNA/mRNA co-expression network was constructed by using the Cytoscape software (V2.8.3, http://www.cytoscape.org/ ).

RESULTS

We observed that 623 lncRNAs and 260 messenger RNAs (mRNAs) were significantly up- or down-regulated (≥2-fold change), and these differences could be used to discriminate cumulus cells of PCOS from those of normal patients. Five differentially expressed lncRNAs (XLOC_011402, ENST00000454271, ENST00000433673, ENST00000450294, and ENST00000432431) were selected to validate the microarray results using quantitative RT-PCR (qRT-PCR). The qRT-PCR results were consistent with the microarray data. Further analysis indicated that many differentially expressed lncRNAs were transcribed from chromosome 2 and may act as enhancers to regulate their neighboring protein-coding genes. Forty-three lncRNAs and 29 mRNAs were used to construct the coding-non-coding gene co-expression network. Most pairs positively correlated, and one mRNA correlated with one or more lncRNAs.

CONCLUSIONS

Our study is the first to determine genome-wide lncRNA expression patterns in cumulus cells isolated from PCOS patients by microarray. The results show that clusters of lncRNAs were aberrantly expressed in cumulus cells of PCOS patients compared with those of normal women, which revealed that lncRNAs differentially expressed in PCOS and normal women may contribute to the occurrence of PCOS and affect oocyte development.

Downregulation of long noncoding RNA NONHSAT037832 in papillary thyroid carcinoma and its clinical significance

Long noncoding RNA (lncRNA) is a kind of RNA that is longer than 200 nucleotides with limited or no protein-coding potential. Studies have proved that lncRNAs play important regulatory roles in gene expression and contribute to oncogenesis and cancer metastasis. However, the expression level of lncRNAs and their clinicopathologic significance in papillary thyroid carcinoma (PTC) have not been well studied. In this study, we investigated the expression level of a novel lncRNA NONHSAT037832 in PTC and paired noncancerous thyroid tissues as well as some cell lines by quantitative real-time polymerase chain reaction. The association between the expression level of NONHSAT037832 and clinicopathologic characteristics of patients with PTC was further analyzed. Three receiver operating characteristic curves (ROCs) were established to evaluate the diagnostic value of NONHSAT037832. The results suggested that the expression level of NONHSAT037832 was significantly decreased in PTC compared with paired noncancerous tissues (P < 0.01). And, NONHSAT037832 was also significantly downregulated in two PTC cell lines (K1 and IHH-4) compared to normal thyroid follicular epithelial cell line Nthy-ori 3-1 (P < 0.01). Downregulated NONHSAT037832 was significantly associated with lymph node metastasis (P = 0.015) and tumor size (P = 0.032). The ROCs revealed that NONHSAT037832 had a high diagnostic value for differentiating between PTC and noncancerous diseases as well as identifying PTC with lymph node metastasis and larger tumors (≥3 cm). The area under curve was up to 0.897 (95%CI = 0.852-0.942, P = 0.000), 0.641 (95%CI = 0.519-0.762, P = 0.033), and 0.702 (95%CI = 0.567-0.827, P = 0.008), respectively. This study indicated that NONHSAT037832 might serve as a potential biomarker of PTC.

Estrogen receptor alpha and beta in health and disease

Estrogen receptors alpha (ERα) and beta (ERβ) are transcription factors that are involved in the regulation of many complex physiological processes in humans. Abnormal ER signaling leads to development of a variety of diseases, such as cancer, metabolic and cardiovascular disease, neurodegeneration, inflammation, and osteoporosis. This review provides an overview and update on ERα and ERβ in health and disease with focus on their role in cancer and metabolic disease and in the context of recent years' success in providing genome wide data on ER function. Furthermore, potential clinical applications and challenges are also discussed.

Sex, epilepsy, and epigenetics

Epilepsy refers to a heterogeneous group of disorders that are associated with a wide range of pathogenic mechanisms, seizure manifestations, comorbidity profiles, and therapeutic responses. These characteristics are all influenced quite significantly by sex. As with other conditions exhibiting such patterns, sex differences in epilepsy are thought to arise-at the most fundamental level-from the "organizational" and "activational" effects of sex hormones as well as from the direct actions of the sex chromosomes. However, our understanding of the specific molecular, cellular, and network level processes responsible for mediating sex differences in epilepsy remains limited. Because increasing evidence suggests that epigenetic mechanisms are involved both in epilepsy and in brain sexual dimorphism, we make the case here that analyzing epigenetic regulation will provide novel insights into the basis for sex differences in epilepsy.