miR-196b targets c-myc and Bcl-2 expression, inhibits proliferation and induces apoptosis in endometriotic stromal cells

miR-503, a microRNA epigenetically repressed in endometriosis, induces apoptosis and cell-cycle arrest and inhibits cell proliferation, angiogenesis, and contractility of human ovarian endometriotic stromal cells

STUDY QUESTION

Is the micro-RNA (miRNA) miR-503, downregulated in endometriotic cyst stromal cells (ECSCs) and does this affect the cell cycle, cell proliferation, angiogenesis and contractility of these cells? SUMMARY ANSWER: miR-503 expression is downregulated in ECSCs by DNA hypermethylation and this contributes to their proliferation, resistance to apoptosis, extracellular matrix (ECM) contractility and angiogenesis through effects on cyclin D1, B-cell lymphoma/leukemia (Bcl)-2, Ras homology A  and vascular endothelial growth factor A (VEGF-A).

WHAT IS KNOWN ALREADY

A variety of miRNAs are demonstrated to involve in the pathogenesis of endometriosis. miR-503 is a miRNA with tumor-suppressor functions, whose expression is suppressed in ECSCs.

STUDY DESIGN, SIZE, DURATION

We isolated ECSCs and normal endometrial stromal cells (NESCs) from ovarian endometriotic tissues (n = 32) and eutopic endometrial tissues without endometriosis (n = 8), respectively.

PARTICIPANTS/MATERIALS, SETTING, METHODS

We investigated the functions of miR-503 by using miR-503-transfected ECSCs and the DNA methylation status of miR-503 gene in ECSCs and NESCs by combined bisulfite restriction analysis.

MAIN RESULTS AND THE ROLE OF CHANCE

In ECSCs, miR-503 is downregulated by the DNA hypermethylation of its gene. The transfection of miR-503 into ECSCs resulted in the inhibition of cell proliferation and induction of cell-cycle arrest at G0/G1 phase through the suppression of cyclin D1, the induction of apoptosis through Bcl-2 suppression, the inhibition of VEGF-A production and the attenuation of ECM contractility via the suppression of Rho/Rho-associated coiled-coil-forming protein kinase-pathways.

LARGE SCALE DATA

NA.

LIMITATIONS, REASONS FOR CAUTION

The present experiments were carried out only with the stromal component of endometriosis and eutopic endometrium. The experiments with the eutopic endometrial stromal cells from women with endometriosis are not performed.

WIDER IMPLICATIONS OF THE FINDINGS

Our findings indicate that epigenetically repressed miR-503 in ECSCs is involved in the acquisition of endometriosis-specific cellular functions.

STUDY FUNDING/COMPETING INTERESTS

This work was supported in part by Grants-in-Aid for Scientific Research from the Japan Society for the Promotion of Science (no. 13237327 to K.N., no. 26861335 to K.K. and no. 23592407 to H.N.) and the Kanzawa Medical Research Foundation (to K.K.). There are no conflicts of interest to declare.

Aberrant DNA hypomethylation of miR-196b contributes to migration and invasion of oral cancer

MicroRNAs (miRs) are a class of small endogenous non-coding RNAs of ~21-24 nucleotides in length. Previous studies have indicated that miR-196b has either an oncogenic or tumor-suppressive function in various types of cancer. However, the biological role of miR-196b in oral squamous cell carcinoma (OSCC) remains unclear. In the present study, the expression levels of miR-196b were examined in oral cancer tissues and corresponding adjacent normal tissues from 69 OSCC patients using stem-loop reverse transcription-quantitative polymerase chain reaction. The results indicated that miR-196b was significantly overexpressed in OSCC tissues compared with the corresponding adjacent normal tissue samples (64 of 69, 92.7%, P<0.001). Analysis of the methylation status of the miR-196b gene indicated more frequent hypomethylation of the CpG islands located upstream of the miR-196b gene in the OSCC tissues than in the adjacent normal tissues (32 of 69, 46.3%), and the methylation status of miR-196b correlated inversely with its expression levels. Furthermore, the unmethylated status of the miR-196b promoter correlated with poor disease-specific survival in OSCC patients (P=0.035). Functional analysis revealed that ectopic miR-196b expression promoted oral cancer cell migration and invasion abilities, and that silencing of miR-196b could abrogate in vitro migration and invasion of oral cancer cells. Collectively, the present findings indicate that the epigenetic regulation of miR-196b expression plays a crucial role in modulating cell migration and invasion during OSCC progression, and thus may serve as a potential prognosis marker or therapeutic target for OSCC.

Activated Hippo/Yes-Associated Protein Pathway Promotes Cell Proliferation and Anti-apoptosis in Endometrial Stromal Cells of Endometriosis

CONTEXT

The imbalance in cell proliferation and apoptosis is considered an important role in the pathogenesis of endometriosis, but the exact mechanisms remains unclear. A newly established signaling pathway–Hippo/Yes-associated protein (YAP) pathway plays a critical role in the proliferation and apoptosis processes. However, studies focusing on Hippo/YAP pathway and endometriosis are lacking.

OBJECTIVE

The objective was to explore the function of the Hippo/YAP pathway in endometriosis.

SETTING AND DESIGN

The expression of YAP was first investigated in endometrium of women with or without endometriosis. The role of YAP in cell proliferation and apoptosis is identified by transfection of endometrial stromal cells (ESCs) in vitro, subsequent Verteporfin treatments in eutopic ESCs in vitro, and endometriosis animal model of nude mice in vivo.

RESULTS

Our results revealed that increased expression of YAP and decreased expression of p-YAP in ectopic and eutopic endometrium compared with normal endometrium. YAP knockdown in eutopic ESCs decreased cell proliferation and enhanced cell apoptosis companied with decreased expression of TEAD1, CTGF, and B-cell lymphoma/leukemia (BCL)-2; whereas overexpression of YAP resulted in increased proliferation and decreased apoptosis of normal ESCs with increased expression of TEAD1, CTGF, and BCL-2. By chromatin immunoprecipitation qPCR CTGF and BCL-2 were identified as directly downstream target genes of YAP-TEAD1 active complex. Eutopic ESCs treated with Verteporfin revealed decreased proliferation and enhanced apoptosis whereas in endometriosis animal models of nude mice treated with Verteporfin, the size of endometriotic lesions was significantly reduced.

CONCLUSIONS

Our study suggests that the Hippo/YAP-signaling pathway plays a critical role in the pathogenesis of endometriosis and should present a novel therapeutic method against endometriosis.

Non-coding RNAs in Uterine Development, Function and Disease

The major function of the uterus is to accept and provide a suitable environment for an embryo, ultimately leading the birth of offspring and successful propagation of the species. For this occur, there must be precise coordination of hormonal signalling within both the endometrial and myometrial components of this organ. Non-coding RNAs, specifically, microRNAs (miRNAs) have been shown to be essential for normal uterine development and function. Within this organ, miRNAs are proposed to fine-tune the actions of the female steroid hormones estradiol and progesterone. Not surprising, mis-expression of miRNAs has been documented in diseases of the endometrium and myometrium such as endometriosis and leiomyomas, respectively. In this chapter, I will review the current understanding on the role, regulation and function of non-coding RNAs focusing on miRNAs in both the normal physiology of the endometrium and myometrium as well as in pathologies of these tissues, namely endometriosis and leiomyomas.

Na/K-ATPase signaling regulates collagen synthesis through microRNA-29b-3p in cardiac fibroblasts

Chronic kidney disease (CKD) is accompanied by cardiac fibrosis, hypertrophy, and dysfunction, which are commonly referred to as uremic cardiomyopathy. Our previous studies found that Na/K-ATPase ligands or 5/6th partial nephrectomy (PNx) induces cardiac fibrosis in rats and mice. The current study used in vitro and in vivo models to explore novel roles for microRNA in this mechanism of cardiac fibrosis formation. To accomplish this, we performed microRNA profiling with RT-qPCR based arrays on cardiac tissue from rats subjected to marinobufagenin (MBG) infusion or PNx. The analysis showed that a series of fibrosis-related microRNAs were dysregulated. Among the dysregulated microRNAs, microRNA (miR)-29b-3p, which directly targets mRNA of collagen, was consistently reduced in both PNx and MBG-infused animals. In vitro experiments demonstrated that treatment of primary cultures of adult rat cardiac fibroblasts with Na/K-ATPase ligands induced significant increases in the fibrosis marker, collagen protein, and mRNA expression compared with controls, whereas miR-29b-3p expression decreased >50%. Transfection of miR-29b-3p mimics into cardiac fibroblasts inhibited cardiotonic steroids-induced collagen synthesis. Moreover, a specific Na/K-ATPase signaling antagonist, pNaKtide, prevented ouabain-induced increases in collagen synthesis and decreases in miR-29b-3p expression in these cells. In conclusion, these data are the first to indicate that signaling through Na/K-ATPase regulates miRNAs and specifically, miR-29b-3p expression both in vivo and in vitro. Additionally, these data indicate that miR-29b-3p expression plays an important role in the formation of cardiac fibrosis in CKD.

Homeobox A9 directly targeted by miR-196b regulates aggressiveness through nuclear Factor-kappa B activity in non-small cell lung cancer cells

MicroRNAs (miRNAs) are recognized as crucial posttranscriptional regulators of gene expression, and play critical roles as oncogenes or tumor suppressors in various cancers. Here, we show that miR-196b is upregulated in mesenchymal-like-state non-small cell lung cancer (NSCLC) cells and lung cancer tissues. Moreover, miR-196b upregulation stimulates cell invasion and a change in cell morphology to a spindle shape via loss of cell-to-cell contacts. We identified homeobox A9 (HOXA9) as a target gene of miR-196b by using public databases such as TargetScan, miRDB, and microRNA.org. HOXA9 expression is inversely correlated with miR-196b levels in clinical NSCLC samples as compared to that in corresponding control samples, and with the migration and invasion of NSCLC cells. Ectopic expression of HOXA9 resulted in a suppression of miR-196b-induced cell invasion, and HOXA9 reexpression increased E-cadherin expression. Furthermore, HOXA9 potently attenuated the expression of snail family zinc finger 2 (SNAI2/SLUG) and matrix metallopeptidase 9 (MMP9) by controlling the binding of nuclear factor-kappa B to the promoter of SLUG and MMP9 genes, respectively. Therefore, we suggest that HOXA9 plays a central role in controlling the aggressive behavior of lung cancer cells and that miR-196b can serve as a potential target for developing anticancer agents. © 2015 Wiley Periodicals, Inc.

Oxidative stress response and Nrf2 signaling in aging

Increasing oxidative stress, a major characteristic of aging, has been implicated in a variety of age-related pathologies. In aging, oxidant production from several sources is increased, whereas antioxidant enzymes, the primary lines of defense, are decreased. Repair systems, including the proteasomal degradation of damaged proteins, also decline. Importantly, the adaptive response to oxidative stress declines with aging. Nrf2/EpRE signaling regulates the basal and inducible expression of many antioxidant enzymes and the proteasome. Nrf2/EpRE activity is regulated at several levels, including transcription, posttranslation, and interactions with other proteins. This review summarizes current studies on age-related impairment of Nrf2/EpRE function and discusses the changes in Nrf2 regulatory mechanisms with aging.

A current view of the role of epigenetic changes in the aetiopathogenesis of endometriosis

The purpose of the study was to examine the role of epigenetic changes in the aetiopathogenesis of endometriosis. The analysis and review of the relevant current literature in English language related to the role of epigenetic changes in the aetiopathogenesis of endometriosis. Epigenetic changes are common denominators for hormonal, immunological and inflammatory aberrations which play a key role in the aetiopathogenesis of endometriosis. Many internal and external factors may cause the different running of the epigenetic mechanism. As yet fully unknown genetic factors may increase the sensitivity of the epigenetic mechanism to various internal and external factors. The breakdown of epigenetic regulation is the main factor initiating the pathogenetic mechanisms for endometriosis formation.

Extremely Low-Frequency Electromagnetic Fields Affect the miRNA-Mediated Regulation of Signaling Pathways in the GC-2 Cell Line

Extremely low-frequency electromagnetic fields (ELF-EMFs) can affect male reproductive function, but the underlying mechanism of this effect remains unknown. miRNA-mediated regulation has been implicated as an important epigenetic mechanism for regulatory pathways. Herein, we profiled miRNA expression in response to ELF-EMFs in vitro. Mouse spermatocyte-derived GC–2 cells were intermittently exposed to a 50 Hz ELF-EMF for 72 h (5 min on/10 min off) at magnetic field intensities of 1 mT, 2 mT and 3 mT. Cell viability was assessed using the CCK–8 assay. Apoptosis and the cell cycle were analyzed with flow cytometry. miRNA expression was profiled using Affymetrix Mouse Genechip miRNA 3.0 arrays. Our data showed that the growth, apoptosis or cell cycle arrest of GC–2 cells exposed to the 50 Hz ELF-EMF did not significantly change. However, we identified a total of 55 miRNAs whose expression significantly changed compared with the sham group, including 19 differentially expressed miRNAs (7 miRNAs were upregulated, and 12 were downregulated) in the 1 mT exposure group and 36 (9 miRNAs were upregulated, and 27 were downregulated) in the 3 mT exposure group. The changes in the expression of 15 selected miRNAs measured by real-time PCR were consistent with the microarray results. A network analysis was used to predict core miRNAs and target genes, including miR-30e-5p, miR-210-5p, miR-196b-5p, miR-504-3p, miR-669c-5p and miR-455-3p. We found that these miRNAs were differentially expressed in response to different magnetic field intensities of ELF-EMFs. GO term and KEGG pathway annotation based on the miRNA expression profiling results showed that miRNAs may regulate circadian rhythms, cytokine-cytokine receptor interactions and the p53 signaling pathway. These results suggested that miRNAs could serve as potential biomarkers, and the miRNA-mediated regulation of signaling pathways might play significant roles in the biological effects of ELF-EMFs.

MiR-183 Regulates ITGB1P Expression and Promotes Invasion of Endometrial Stromal Cells

We applied in the previous study miRNA microarray screening analysis to identify several differentially expressed miRNAs, including miR-183 in normal, eutopic, and ectopic endometrium. Knockdown of miR-183 expression induced the invasiveness and inhibition of apoptosis in endometrial stromal cells. The current study aims to identify the miR-183 targets with relevance to cell functions in endometrial stromal cells, to verify the interaction of miR-183 with its target genes, and to confirm the role of miR-183 in the process of endometriosis. Using microarray analysis, we identified 27 differentially expressed genes (19 were upregulated and 8 downregulated), from which we selected 4 downregulated genes (ITGB1, AMIGO2, VAV3, and PSEN2) based on GO databases for functional analysis and significant pathway analysis. Western blotting analyses showed that integrin β1 (ITGB1), but not AMIGO2, was affected by miR-183 overexpression, whereas no protein expression of VAV3 and PSEN2 was detected. Luciferase reporter assay verified that ITGB1 is a target gene of miR-183. Moreover, we found that ITGB1 is overexpressed in the endometrium of endometriosis patients. Furthermore, overexpression of ITGB1 rescued the repressive effects of miR-183 on the invasiveness of endometrial stromal cells. These findings, together with the fact that ITGB1 is a critical factor for cell adhesion and invasiveness, suggest that miR-183 may be involved in the development of endometriosis by regulating ITGB1 in endometrial stromal cells.

miRNA-196b inhibits cell proliferation and induces apoptosis in HepG2 cells by targeting IGF2BP1

Background

Tumor hypoxia is one of the features of tumor microenvironment that contributes to chemoresistance. miRNAs have recently been shown to play important roles in tumorigenesis and drug resistance. Moreover, hypoxia also regulates the expression of a series of miRNAs. However, the interaction between chemoresistance, hypoxia and miRNAs has not been explored yet. The aim of this study is to understand the mechanisms activated/inhibited by miRNAs under hypoxia that induce resistance to chemotherapy-induced apoptosis.

Methods

TaqMan low-density array was used to identify changes in miRNA expression when cells were exposed to etoposide under hypoxia or normoxia. The effects of miR-196b overexpression on apoptosis and cell proliferation were studied in HepG2 cells. miR-196b target mRNAs were identified by proteomic analysis, luciferase activity assay, RT-qPCR and western blot analysis.

Results

Results showed that hypoxia down-regulated miR-196b expression that was induced by etoposide. miR-196b overexpression increased the etoposide-induced apoptosis and reversed the protection of cell death observed under hypoxia. By a proteomic approach combined with bioinformatics analyses, we identified IGF2BP1 as a potential target of miR-196b. Indeed, miR-196b overexpression decreased IGF2BP1 RNA expression and protein level. The IGF2BP1 down-regulation by either miR-196b or IGF2BP1 siRNA led to an increase in apoptosis and a decrease in cell viability and proliferation in normal culture conditions. However, IGF2BP1 silencing did not modify the chemoresistance induced by hypoxia, probably because it is not the only target of miR-196b involved in the regulation of apoptosis.

Conclusions

In conclusion, for the first time, we identified IGF2BP1 as a direct and functional target of miR-196b and showed that miR-196b overexpression reverses the chemoresistance induced by hypoxia. These results emphasize that the chemoresistance induced by hypoxia is a complex mechanism.

Electronic supplementary material

The online version of this article (doi:10.1186/s12943-015-0349-6) contains supplementary material, which is available to authorized users.

Enhanced miR-210 expression promotes the pathogenesis of endometriosis through activation of signal transducer and activator of transcription 3

STUDY QUESTION

What are the roles of the microRNA miR-210-an miRNA that is up-regulated in endometriotic cyst stromal cells (ECSCs)-in the pathogenesis of endometriosis?

SUMMARY ANSWER

Up-regulated miR-210 expression in ECSCs is involved in their proliferation, resistance to apoptosis and angiogenesis through signal transducer and activator of transcription (STAT) 3.

WHAT IS KNOWN ALREADY

In the pathogenesis of endometriosis, a number of roles for microRNAs (miRNAs) are becoming apparent.

STUDY DESIGN, SIZE, DURATION

ECSCs and normal endometrial stromal cells (NESCs) were isolated from ovarian endometriotic tissues (patients aged 24-40 years undergoing salpingo-oophorectomy or evisceration for the treatment of ovarian endometriotic cysts, n = 10) and the eutopic endometrial tissues without endometriosis (premenopausal patients aged 35-45 years undergoing hysterectomies for subserousal leiomyoma, n = 13), respectively.

PARTICIPANTS/MATERIALS, SETTING, METHODS

We used a global gene expression microarray technique to identify downstream targets of miR-210, and we assessed the functions of miR-210 in the pathogenesis of endometriosis by using the miR-210-transfected NESCs.

MAIN RESULTS AND THE ROLE OF CHANCE

Gene expression microarray analysis revealed that one of the key target molecules of miR-210 is STAT3. In the NESCs, in comparison to the control, miR-210 transfection resulted in the induction of cell proliferation (P < 0.0005), the production of vascular endothelial cell growth factor (VEGF) (P < 0.0005) and the inhibition of apoptosis (P < 0.05) through STAT3 activation [increased levels of mRNA (P < 0.0005), and protein (P < 0.005)]. In the ECSCs, inhibitors of STAT3 inhibited the cell proliferation and VEGF production (P < 0.05), and induced the apoptosis of these cells (P < 0.05).

LIMITATIONS, REASONS FOR CAUTION

The roles of aberrant miR-210 expression were investigated only in the stromal component of ectopic and eutopic endometrium. Control endometrial tissues were obtained from premenopausal patients who had subserosal leiomyoma and NESC gene expression patterns may be altered in these women. Furthermore, the effects of STAT3 inhibitors were evaluated only in ECSCs and not in NESCs.

WIDER IMPLICATIONS OF THE FINDINGS

The present findings indicate that miR-210 induces NESCs to differentiate into the endometriotic phenotype and we speculate that up-regulated miR-210 expression in ECSCs is involved in the creation of the endometriosis-specific cellular dysfunctions through epigenetic mechanisms. The data indicate that STAT3 inhibitors may be promising candidates for the treatment of endometriosis.

STUDY FUNDING/COMPETING INTERESTS

This work was supported in part by Grants-in-Aid for Scientific Research from the Japan Society for the Promotion of Science (no. 13237327 to K.N., no. 25861500 to Y.K. and no. 23592407 to H.N.). There are no conflicts of interest to declare.

Wisteria floribunda agglutinin-binding glycan expression is decreased in endometriomata

BACKGROUND

Glycosylation is one of the most common post-translational modifications of eukaryotic proteins and is known to undergo dynamic changes in a wide range of biological processes. To date, however, the glycan expression profiles in endometriosis are largely unknown. The objective of the study was to identify the panel of glycans that were aberrantly expressed in endometriosis, a hormone-dependent disease.

METHODS

The glycan expression profiles in primary cultured human endometriotic cyst stromal cells (ECSCs) and normal endometrial stromal cells (NESCs) were determined by lectin microarray analysis. Distribution of Wisteria floribunda agglutinin (WFA)-binding glycans in ovarian endometriotic cysts and eutopic proliferative phase endometrium were assessed by lectin histochemistry. The expressions of N-acetylgalactosaminyl transferases that synthesize WFA-binding glycans were evaluated in ECSCs and NESCs.

RESULTS

We found that the levels of WFA-binding glycans were decreased in ECSCs. Lectin histochemistry revealed that WFA-binding glycans were decreased only in the stromal components of the ovarian endometriotic cysts, but not in the epithelial components, compared to the eutopic proliferative phase endometrium. The expressions of N-acetylgalactosaminyl transferases that synthesize WFA-binding glycans were downregulated in ECSCs.

CONCLUSIONS

Utilizing lectin microarray analysis and lectin histochemistry, we found that WFA-binding glycans were decreased in endometriosis. The synthetic enzymes of WFA-binding glycans were significantly downregulated in ECSCs. It is suggested that reduced expression of N-glycans with WFA-binding properties on ECSCs is a novel characteristics of endometriosis.

Embryonic miRNA profiles of normal and ectopic pregnancies

Our objective was to investigate the miRNA profile of embryonic tissues in ectopic pregnancies (EPs) and controlled abortions (voluntary termination of pregnancy; VTOP). Twenty-three patients suffering from tubal EP and twenty-nine patients with a normal ongoing pregnancy scheduled for a VTOP were recruited. Embryonic tissue samples were analyzed by miRNA microarray and further validated by real time PCR. Microarray studies showed that four miRNAs were differentially downregulated (hsa-mir-196b, hsa-mir-30a, hsa-mir-873, and hsa-mir-337-3p) and three upregulated (hsa-mir-1288, hsa-mir-451, and hsa-mir-223) in EP compared to control tissue samples. Hsa-miR-196, hsa-miR-223, and hsa-miR-451 were further validated by real time PCR in a wider population of EP and control samples. We also performed a computational analysis to identify the gene targets and pathways which might be modulated by these three differentially expressed miRNAs. The most significant pathways found were the mucin type O-glycan biosynthesis and the ECM-receptor-interaction pathways. We also checked that the dysregulation of these three miRNAs was able to alter the expression of the gene targets in the embryonic tissues included in these pathways such as GALNT13 and ITGA2 genes. In conclusion, analysis of miRNAs in ectopic and eutopic embryonic tissues shows different expression patterns that could modify pathways which are critical for correct implantation, providing new insights into the understanding of ectopic implantation in humans.

MicroRNA-155 and microRNA-196b: promising biomarkers in hepatitis C virus infection?

MicroRNAs (miRNAs) are a class of small, evolutionarily conserved, noncoding RNA that regulate several important cellular processes. The versatility of these molecules allowed the accurate predictions that they would also affect the replication and life cycle of HCV. In this review, emphasis has been given to two selected miRNAs: miR-155 and miR-196b. Recent data indicate that miR-155 is overexpressed in HCV-infected patients, inducing an inflammatory state, and promoting virus replication and persistence even after the completion of antiviral treatment. It is also associated with the increased proliferation and inhibited apoptosis of hepatocytes, which promotes the growth of liver tumors. In contrast, miR-196b is reported as a factor inhibiting HCV replication with cytoprotective, anti-inflammatory, and antioxidant properties. Growing evidence suggests that these molecules could be used as potential prognostic and predictive factors and their antagonists or mimics as a promising therapeutic approach in HCV-infected patients.

Identification of serum microRNA biomarkers for tuberculosis using RNA-seq

Tuberculosis (TB) remains a significant human health issue. More effective biomarkers for use in tuberculosis prevention, diagnosis, and treatment, including markers that can discriminate between healthy individuals and those with latent infection, are urgently needed. To identify a set of such markers, we used Solexa sequencing to examine microRNA expression in the serum of patients with active disease, healthy individuals with latent TB, and those with or without prior BCG inoculation. We identified 24 microRNAs that are up-regulated (2.85–1285.93 fold) and 6 microRNAs that are down-regulated (0.003–0.11 fold) (P<0.05) in patients with active TB relative to the three groups of healthy controls. In addition, 75 microRNAs were up-regulated (2.05–2454.58 fold) and 11 were down-regulated (0.001–0.42 fold) (P<0.05) in latent-TB infected individuals relative to BCG- inoculated individuals. Of interest, 134 microRNAs were differentially-expressed in BCG-inoculated relative to un-inoculated individuals (18 up-regulated 2.9–499.29 fold, 116 down-regulated 0.0002–0.5 fold), providing insights into the effects of BCG inoculation at the microRNA level. Target prediction of differentially-expressed microRNAs by microRNA-Gene Network analysis and analysis of pathways affected suggest that regulation of the host immune system by microRNAs is likely to be one of the main factors in the pathogenesis of tuberculosis. qRT-PCR validation indicated that hsa-miR-196b and hsa-miR-376c have potential as markers for active TB disease. The microRNA differential-expression profiles generated in this study provide a good foundation for the development of markers for TB diagnosis, and for investigations on the role of microRNAs in BCG-inoculated and latent-infected individuals.

Overexpression of lysine-specific demethylase 1 in ovarian endometriomas and its inhibition reduces cellular proliferation, cell cycle progression, and invasiveness

OBJECTIVE

To investigate whether lysine-specific demethylase 1 (LSD1) is aberrantly expressed in endometriomas and whether treatment with tranylcypromine, an LSD1 inhibitor, has any effect on cell viability, cell cycle, and invasiveness.

DESIGN

Laboratory study using human tissues.

SETTING

Academic hospital.

PATIENT(S)

Forty-two ectopic endometrial tissue samples, their homologue eutopic endometrial tissue samples, and 70 control endometrial tissue samples.

INTERVENTION(S)

Immunohistochemistry analysis of LSD1 of all human tissue samples, and Western blot analysis, quantitative real-time reverse-transcription polymerase chain reaction analysis, cell viability assay, cell cycle analysis, and invasion assay of eutopic and ectopic endometriotic stromal cells and normal endometrial stromal cells.

MAIN OUTCOME MEASURE(S)

Immunostaining levels of LSD1, gene and protein expression levels, cell viability, cell cycles, and invasiveness.

RESULT(S)

The expression of the LSD1 gene and protein in endometriosis was elevated. Treatment of endometriotic stromal cells with tranylcypromine statistically significantly reduced the cellular proliferation, cell cycle progression, and invasiveness.

CONCLUSION(S)

Because DNA and histones are intimately intertwined and work in concert in transcription regulation, conceivably histone demethylation activity of LSD1 could be wide ranging. The inhibition of LSD1 activity by tranylcypromine and the resultant inhibition of proliferation, cell cycle progression, and invasiveness suggest that LSD1 may be a candidate therapeutic target for endometriosis.

The return of the nucleus: transcriptional and epigenetic control of autophagy

Autophagy is a conserved process by which cytoplasmic components are degraded by the lysosome. It is commonly seen as a cytoplasmic event and, until now, nuclear events were not considered of primary importance for this process. However, recent studies have unveiled a transcriptional and epigenetic network that regulates autophagy. The identification of tightly controlled transcription factors (such as TFEB and ZKSCAN3), microRNAs and histone marks (especially acetylated Lys16 of histone 4 (H4K16ac) and dimethylated H3K9 (H3K9me2)) associated with the autophagic process offers an attractive conceptual framework to understand the short-term transcriptional response and potential long-term responses to autophagy.

DNA methyltransferases and TETs in the regulation of differentiation and invasiveness of extra-villous trophoblasts

Specialized cell types of trophoblast cells form the placenta in which each cell type has particular properties of proliferation and invasion. The placenta sustains the growth of the fetus throughout pregnancy and any aberrant trophoblast differentiation or invasion potentially affects the future health of the child and adult. Recently, the field of epigenetics has been applied to understand differentiation of trophoblast lineages and embryonic stem cells (ESC), from fertilization of the oocyte onward. Each trophoblast cell-type has a distinctive epigenetic profile and we will concentrate on the epigenetic mechanism of DNA methyltransferases and TETs that regulate DNA methylation. Environmental factors affecting the mother potentially regulate the DNA methyltransferases in trophoblasts, and so do steroid hormones, cell cycle regulators, such as p53, and cytokines, especially interlukin-1β. There are interesting questions of why trophoblast genomes are globally hypomethylated yet specific genes can be suppressed by hypermethylation (in general, tumor suppressor genes, such as E-cadherin) and how invasive cell-types are liable to have condensed chromatin, as in metastatic cancer cells. Future work will attempt to understand the interactive nature of all epigenetic mechanisms together and their effect on the complex biological system of trophoblast differentiation and invasion in normal as well as pathological conditions.

Reduced circulating miR-196b levels is associated with preeclampsia

MicroRNAs (miRs) are small noncoding RNAs, highly stable in plasma, that regulate gene expression by base-pairing to the 3'-untranslated region of target mRNAs. We compared the expression of 3 circulating miRs (miR-125b, miR-146a, and miR-196b), which is related to the control of cell proliferation, differentiation, and apoptosis in preeclamptic (n=19) and healthy pregnant women (n=14). We found that women with preeclampsia (PE) presented lower expression of miR-196b (-2.9-fold change). The other miRs were at similar levels. This study is the first to demonstrate this difference, and highlights new opportunities for investigation into the role of miRs in PE.

Genetic, epigenetic and stem cell alterations in endometriosis: new insights and potential therapeutic perspectives

Human endometrium is a highly dynamic tissue, undergoing periodic growth and regression at each menstrual cycle. Endometriosis is a frequent chronic pathological status characterized by endometrial tissue with an ectopic localization, causing pelvic pain and infertility and a variable clinical presentation. In addition, there is well-established evidence that, although endometriosis is considered benign, it is associated with an increased risk of malignant transformation in approximately 1.0% of affected women, with the involvement of multiple pathways of development. Increasing evidence supports a key contribution of different stem/progenitor cell populations not only in the cyclic regeneration of eutopic endometrium, but also in the pathogenesis of at least some types of endometriosis. Evidence has arisen from experiments in animal models of disease through different kinds of assays (including clonogenicity, the label-retaining cell approach, the analysis of undifferentiation markers), as well as from descriptive studies on ectopic and eutopic tissue samples harvested from affected women. Changes in stem cell populations in endometriotic lesions are associated with genetic and epigenetic alterations, including imbalance of miRNA expression, histone and DNA modifications and chromosomal aberrations. The present short review mainly summarizes the latest observations contributing to the current knowledge regarding the presence and the potential contribution of stem/progenitor cells in eutopic endometrium and the aetiology of endometriosis, together with a report of the most recently identified genetic and epigenetic alterations in endometriosis. We also describe the potential advantages of single cell molecular profiling in endometrium and in endometriotic lesions. All these data can have clinical implications and provide a basis for new potential therapeutic applications.

Death receptor 6 is epigenetically silenced by histone deacetylation in endometriosis and promotes the pathogenesis of endometriosis

PROBLEM

The purpose of this study is to evaluate the involvement of death receptor (DR) 6 in the pathogenesis of endometriosis.

METHODS OF STUDY

Endometriotic cyst stromal cells (ECSCs) and normal endometrial stromal cells (NESCs) were isolated from ovarian endometriotic tissues and the eutopic endometrial tissues, respectively. The effect of valproic acid (VPA) on the DR6 expression in ECSCs was examined. The roles of DR6 in NESC proliferation and apoptosis were investigated with DR6 siRNA transfection. The distribution of DR6 protein in ovarian endometriotic tissues and normal proliferative-phase endometrium was examined by immunohistochemistry. The expression of DR6 mRNA and protein in ECSCs and NESCs was also examined.

RESULTS

Death receptor 6 expression was attenuated in ECSCs and in endometriotic tissues, and its expression was upregulated by VPA stimulation. VPA treatment resulted in an accumulation of acetylated histone H4 in the promoter region of the DR6 gene. DR6 knockdown directed the stimulation of cell proliferation and the resistance to apoptosis in NESCs.

CONCLUSION

The present findings suggested that DR6 is involved in the pathogenesis of endometriosis by creating the proliferative and anti-apoptotic characteristics of endometriosis. The results also suggest that histone deacetylase inhibitors are promising agents for the treatment of endometriosis.

Tissue and circulating microRNA influence reproductive function in endometrial disease

microRNA (miRNA) have emerged as important epigenetic modulators of gene expression in diverse pathological and physiological processes. In the endometrium, miRNA appear to have a role in the dynamic changes associated with the menstrual cycle, in implantation and in the pathophysiology associated with reproductive disorders such as recurrent miscarriage and endometriosis. This review explores the role of miRNA in endometrial physiology and endometrial disorders of reproduction and also raises the prospect that circulating miRNA may modulate endometrial function or reflect disordered endometrial activity. The clinical potential to use miRNA in diagnostic tests of endometrial function or in the treatment of endometrial disorders will also be discussed.

Low expression of miR-196b enhances the expression of BCR-ABL1 and HOXA9 oncogenes in chronic myeloid leukemogenesis

MicroRNAs (miRNAs) can function as tumor suppressors or oncogene promoters during tumor development. In this study, low levels of expression of miR-196b were detected in patients with chronic myeloid leukemia. Bisulfite genomic sequencing PCR and methylation-specific PCR were used to examine the methylation status of the CpG islands in the miR-196b promoter in K562 cells, patients with leukemia and healthy individuals. The CpG islands showed more methylation in patients with chronic myeloid leukemia compared with healthy individuals (P<0.05), which indicated that low expression of miR-196b may be associated with an increase in the methylation of CpG islands. The dual-luciferase reporter assay system demonstrated that BCR-ABL1 and HOXA9 are the target genes of miR-196b, which was consistent with predictions from bioinformatics software analyses. Further examination of cell function indicated that miR-196b acts to reduce BCR-ABL1 and HOXA9 protein levels, decrease cell proliferation rate and retard the cell cycle. A low level of expression of miR-196b can cause up-regulation of BCR-ABL1 and HOXA9 expression, which leads to the development of chronic myeloid leukemia. MiR-196b may represent an effective target for chronic myeloid leukemia therapy.