Endometriosis-specific genes identified by real-time reverse transcription-polymerase chain reaction expression profiling of endometriosis versus autologous uterine endometrium

PIM2 Promotes the Development of Ovarian Endometriosis by Enhancing Glycolysis and Fibrosis

Endometriosis is a common gynecological disorder characterized by the presence of the endometrial glands and the stroma outside the uterine cavity. The disease affects reproductive function and quality of life in women of reproductive age. Endometriosis is similar to tumors in some characteristics, such as glycolysis. PIM2 can promote the development of tumors, but the mechanism of PIM2 in endometriosis is still unclear. Therefore, our goal is to study the mechanism of PIM2 in endometriosis. Through immunohistochemistry, we found PIM2, HK2, PKM2, SMH (smooth muscle myosin heavy chain), Desmin, and α-SMA (α-smooth muscle actin) were strongly expressed in the ovarian endometriosis. In endometriotic cells, PIM2 enhanced glycolysis and fibrosis via upregulating the expression of PKM2. Moreover, the PIM2 inhibitor SMI-4a inhibited the development of endometriosis. And we established a PIM2 knockout mouse model of endometriosis to demonstrate the role of PIM2 in vivo. In summary, our study indicates that PIM2 promotes the development of endometriosis. PIM2 may serve as a promising therapeutic target for endometriosis.

Global Analysis of Transcription Start Sites and Enhancers in Endometrial Stromal Cells and Differences Associated with Endometriosis

Identifying tissue-specific molecular signatures of active regulatory elements is critical to understanding gene regulatory mechanisms. In this study, transcription start sites (TSS) and enhancers were identified using Cap analysis of gene expression (CAGE) across endometrial stromal cell (ESC) samples obtained from women with (n = 4) and without endometriosis (n = 4). ESC TSSs and enhancers were compared to those reported in other tissue and cell types in FANTOM5 and were integrated with RNA-seq and ATAC-seq data from the same samples for regulatory activity and network analyses. CAGE tag count differences between women with and without endometriosis were statistically tested and tags within close proximity to genetic variants associated with endometriosis risk were identified. Over 90% of tag clusters mapping to promoters were observed in cells and tissues in FANTOM5. However, some potential cell-type-specific promoters and enhancers were also observed. Regions of open chromatin identified using ATAC-seq provided further evidence of the active transcriptional regions identified by CAGE. Despite the small sample number, there was evidence of differences associated with endometriosis at 210 consensus clusters, including IGFBP5, CALD1 and OXTR. ESC TSSs were also located within loci associated with endometriosis risk from genome-wide association studies. This study provides novel evidence of transcriptional differences in endometrial stromal cells associated with endometriosis and provides a valuable cell-type specific resource of active TSSs and enhancers in endometrial stromal cells.

Research advances in endometriosis-related signaling pathways: A review

Endometriosis (EM) is characterized by the existence of endometrial mucosa outside the uterine cavity, which causesinfertility, persistent aches, and a decline in women's quality of life. Both hormone therapies and nonhormone therapies, such as NSAIDs, are ineffective, generic categories of EM drugs. Endometriosis is a benign gynecological condition, yet it shares a number of features with cancer cells, including immune evasion, survival, adhesion, invasion, and angiogenesis. Several endometriosis-related signaling pathways are comprehensively reviewed in this article, including E2, NF-κB, MAPK, ERK, PI3K/Akt/mTOR, YAP, Wnt/β-catenin, Rho/ROCK, TGF-β, VEGF, NO, iron, cytokines and chemokines. To find and develop novel medications for the treatment of EM, it is essential to implicitly determine the molecular pathways that are disordered during EM development. Additionally, research on the shared pathways between EM and tumors can provide hypotheses or suggestions for endometriosis therapeutic targets.

Phosphorylation of PFKFB4 by PIM2 promotes anaerobic glycolysis and cell proliferation in endometriosis

Endometriosis (EM) is one of the vanquished wonted causes of chronic pelvic sting in women and is closely associated with infertility. The long-term, complex, systemic, and post-treatment recurrence of EM wreaks havoc on women's quality of life. Extensive metabolic reprogramming (aerobic glycolysis, glucose overweening intake, and high lactate production) and cancer-like changes have been found in EM, which bears striking similarities to tumorigenesis. The key glycolysis regulator PFKFB4 is overexpressed in EM. However, the mechanism of PFKFB4 in EM remains unknown. We found that PFKFB4 was upregulated and was closely related to the progression of EM. We identified focus PIM2 as a new pioneering adjoin protein of PFKFB4. Vigorous biochemical methods were used to confirm that PIM2 phosphorylated site Thr140 of PFKFB4. PIM2 also could enhance PFKFB4 protein expression through the ubiquitin-proteasome pathway. Moreover, PIM2 expression was really corresponding prevalent with PFKFB4 in endometriosis in vivo. Importantly, phosphorylation of PFKFB4 on Thr140 by PIM2 promoted EM glycolysis and cell growth. Our study demonstrates that PIM2 mediates PFKFB4 Thr140 phosphorylation thus regulating glycolysis and EM progression. We illustrated a new mechanism that PIM2 simulated a central upstream partnership in the regulation of PFKFB4, and reveal a novel means of PIM2-PFKFB4 setting EM growth. Our research provided new theoretical support for further clarifying the reprogramming of EM glucose metabolism, and provided new clues for exploring non-contraceptive treatments for EM.

Single-cell analysis of menstrual endometrial tissues defines phenotypes associated with endometriosis

BACKGROUND

Endometriosis is a common, complex disorder which is underrecognized and subject to prolonged delays in diagnosis. It is accompanied by significant changes in the eutopic endometrial lining.

METHODS

We have undertaken the first single-cell RNA-sequencing (scRNA-Seq) comparison of endometrial tissues in freshly collected menstrual effluent (ME) from 33 subjects, including confirmed endometriosis patients (cases) and controls as well as symptomatic subjects (who have chronic symptoms suggestive of endometriosis but have not been diagnosed).

RESULTS

We identify a unique subcluster of proliferating uterine natural killer (uNK) cells in ME-tissues from controls that is almost absent from endometriosis cases, along with a striking reduction of total uNK cells in the ME of cases (p < 10^-16). In addition, an IGFBP1+ decidualized subset of endometrial stromal cells are abundant in the shed endometrium of controls when compared to cases (p < 10^-16) confirming findings of compromised decidualization of cultured stromal cells from cases. By contrast, endometrial stromal cells from cases are enriched in cells expressing pro-inflammatory and senescent phenotypes. An enrichment of B cells in the cases (p = 5.8 × 10^-6) raises the possibility that some may have chronic endometritis, a disorder which predisposes to endometriosis.

CONCLUSIONS

We propose that characterization of endometrial tissues in ME will provide an effective screening tool for identifying endometriosis in patients with chronic symptoms suggestive of this disorder. This constitutes a major advance, since delayed diagnosis for many years is a major clinical problem in the evaluation of these patients. Comprehensive analysis of ME is expected to lead to new diagnostic and therapeutic approaches to endometriosis and other associated reproductive disorders such as female infertility.

Upregulated Fibulin-1 Increased Endometrial Stromal Cell Viability and Migration by Repressing EFEMP1-Dependent Ferroptosis in Endometriosis

Endometriosis (EMS) is a prevalent disease in women characterized by the presence of endometrial stroma and glands outside the uterus. Recent studies have showed that EMS is correlated with the resistance of endometrial stromal cells (ESCs) to ferroptosis, an iron-dependent nonapoptotic cell death. Fibulin-1 (FBLN1) is a newly identified target regulated by progesterone in the process of ESC decidualization. However, the role of FBLN1 in regulating ESC ferroptosis and EMS remains unclear. In the present study, the gene expression profiles of GSE58178, GSE23339, and GSE25628 were downloaded from the Gene Expression Omnibus (GEO) database, and the commonly differential genes were identified using Venn diagram analysis. The role of FBLN1 in ESC viability and migration was evaluated using Cell Counting Kit-8, transwell, and western blot analysis. We found that the FBLN1 expression was increased significantly in eutopic and ectopic endometrial tissues of patients with EMS compared with normal endometrium. FBLN1 overexpression in normal ESCs (NESCs) promoted cell viability and migration, whereas FBLN1 inhibition in ectopic ESCs (EESCs) decreased cell viability and migration. Furthermore, FBLN1 inhibition facilitated EESC death by triggering ferroptosis, as evidenced by increased Fe2+, lipid ROS, and malondialdehyde (MDA) level and decreased glutathione peroxidase 4 (GPX4) expression and glutathione (GSH) level. Mechanistically, FBLN1 interacted with EGF-containing fibulin-like extracellular matrix protein 1 (EFEMP1) and increased the protein stability of EFEMP1. More importantly, EFEMP1 silencing repressed the effect of FBLN1 on regulating EESC ferroptosis, death, and migration. Taken together, these results verify the role of the FBLN1/EFEMP1/ferroptosis pathway in the pathogenesis of EMS, and silencing of FBLN1/EFEMP1 might be an effective approach to treat EMS.

Effect of Levetiracetam on Cognitive Function and Clonic Seizure Frequency in Children with Epilepsy

Background:

This study aimed to explore the clinical effect of levetiracetam in the treatment of children with epilepsy.

Methods:

136 children with epilepsy were selected from January 2017 to December 2017. According to the random number table method, they were divided into the experimental group and the conventional group, with 68 cases in each group. The conventional group was treated with valproate, while the experimental group was treated with levetiracetam. The effective rate, the cognitive function and the frequency of clonic seizures in the two groups were compared.

Results:

There was no significant difference in the total effective rate between the two groups (P>0.05). There was no significant difference in attention, executive ability, abstract and orientation scores between the two groups before treatment (P>0.05). After treatment, the focus of attention (106.54±6.56), executive ability (105.76±6.77), abstract and directional score (106.65±6.57) were significantly higher than that of the conventional group. The difference in the two groups was statistically significant (P<0.05). After 3 months of treatment, the frequency of myoclonic seizures (9.22±0.95) and the frequency of tonic-clonic seizures (11.68±1.36) were found to be significantly lower than those of the conventional group, and the difference between the two groups was statistically significant (P<0.05).

Conclusion:

Levetiracetam is effective in the treatment of children with epilepsy. It can effectively improve the cognitive function of the patients, reduce the frequency of myoclonic seizures and tonic-clonic seizures, and has a high promotion value.

Curcumin attenuates proangiogenic and proinflammatory factors in human eutopic endometrial stromal cells through the NF-κB signaling pathway

Endometriosis is a chronic gynecological inflammatory disorder in which immune system dysregulation is thought to play a role in its initiation and progression. Due to altered sex steroid receptor concentrations and other signaling defects, eutopic endometriotic tissues have an attenuated response to progesterone. This progesterone-resistance contributes to lesion survival, proliferation, pain, and infertility. The current agency-approved hormonal therapies, including synthetic progestins, GnRH agonists, and danazol are often of limited efficacy and counterproductive to fertility and cause systemic side effects due to suppression of endogenous steroid hormone levels. In the current study, we examined the effects of curcumin (CUR, diferuloylmethane), which has long been used as an anti-inflammatory folk medicine in Asian countries for this condition. The basal levels of proinflammatory and proangiogenic chemokines and cytokines expression were higher in primary cultures of stromal cells derived from eutopic endometrium of endometriosis (EESC) subjects compared with normal endometrial stromal cells (NESC). The treatment of EESC and NESC with CUR significantly and dose-dependently reduced chemokine and cytokine secretion over the time course. Notably, CUR treatment significantly decreased phosphorylation of the IKKα/β, NF-κB, STAT3, and JNK signaling pathways under these experimental conditions. Taken together, our findings suggest that CUR has therapeutic potential to abrogate aberrant activation of chemokines and cytokines, and IKKα/β, NF-κB, STAT3, and JNK signaling pathways to reduce inflammation associated with endometriosis.

New knowledge and insights about the malignant transformation of endometriosis

Endometriosis may be a definitive risk factor for ovarian cancer, the most fatal gynecological cancer. The ability of endometriosis to transform into malignancy, first described by Dr. Sampson in 1925, is considered a rare occurrence, affecting approximately 1% of ovarian endometriomas. Recently we conducted a retrospective study regarding the malignant transformation of endometriosis in Japanese women. Many studies have reported a consistent correlation between endometriosis and ovarian cancer according to histological subtypes. However, the existing epidemiological evidence linking this association is insufficient to define the role of endometriosis as a cause of ovarian cancer and to influence changes to current clinical practice. Prospective cohort studies are therefore needed to clarify this issue. Additionally, the results of many molecular studies are conflicting, and earlier studies showing the molecular aberrations involved in genomic instability and mutation that enable malignant transformation have not been replicated in later studies. Careful long-term observation of a patient with endometrioma is required to detect possible subsequent incidence of malignant transformation. More importantly, a precise strategy should be set up for better prevention, early detection, specific diagnosis and treatment targeting molecular pathogenesis to understand the mechanisms of endometriosis-associated ovarian cancer. Clinicians need to be aware of the increased ovarian cancer risk in women with endometriosis.

Comparative analysis of molecular signatures suggests the use of gabapentin for the management of endometriosis-associated pain

Background

It has been repetitively shown that the transcription factors DLX5 and DLX6 are drastically downregulated in endometriotic lesions when compared with eutopic endometrium. These findings suggest that regulatory cascades involving DLX5/6 might be at the origin of endometriosis symptoms such as chronic pelvic pain (CPP). We have shown that inactivation of Dlx5 and Dlx5/6 in the mouse uterus results in an endometrial phenotype reminiscent of endometriosis.

Methods

We focused on genes that present a similar deregulation in endometriosis and in Dlx5/6-null mice in search of new endometriosis targets.

Results

We confirmed a strong reduction of DLX5 expression in endometriosis implants. We identified a signature of 30 genes similarly deregulated in human endometriosis implants and in Dlx5/6-null mouse uteri, reinforcing the notion that the downregulation of Dlx5/6 is an early event in the progress of endometriosis. CACNA2D3, a component of the α2δ family of voltage-dependent calcium channel complex, was strongly overexpressed both in mutant mouse uteri and in endometriosis implants, were also CACNA2D1 and CACNA2D2, other members of the α2δ family involved in nociception, are upregulated.

Conclusion

Comparative analysis of gene expression signatures from endometriosis and mouse models showed that calcium channel subunits α2δ involved in nociception can be targets for the treatment of endometriosis-associated pain. CACNA2D3 has been associated with pain sensitization and heat nociception in animal models. In patients, CACNA2D3 variants were associated with reduced sensitivity to acute noxious stimuli. As α2δs were targets of gabapentinoid analgesics, the results suggested the use of these drugs for the treatment of endometriosis-associated pain. Indeed, recent small-scale clinical studies have shown that gabapentin could be effective in women with CPP. The findings of this study reinforce the need for a large definitive trial.

Endometriosis risk alleles at 1p36.12 act through inverse regulation of CDC42 and LINC00339

Genome-wide association studies (GWAS) have identified markers within the WNT4 region on chromosome 1p36.12 showing consistent and strong association with increasing endometriosis risk. Fine mapping using sequence and imputed genotype data has revealed strong candidates for the causal SNPs within these critical regions; however, the molecular pathogenesis of these SNPs is currently unknown. We used gene expression data collected from whole blood from 862 individuals and endometrial tissue from 136 individuals from independent populations of European descent to examine the mechanism underlying endometriosis susceptibility. Association mapping results from 7,090 individuals (2,594 cases and 4,496 controls) supported rs3820282 as the SNP with the strongest association for endometriosis risk (P = 1.84 × 10−5, OR = 1.244 (1.126-1.375)). SNP rs3820282 is a significant eQTL in whole blood decreasing expression of LINC00339 (also known as HSPC157) and increasing expression of CDC42 (P = 2.0 ×10−54 and 4.5x10−4 respectively). The largest effects were for two LINC00339 probes (P = 2.0 ×10−54; 1.0 × 10−34). The eQTL for LINC00339 was also observed in endometrial tissue (P = 2.4 ×10−8) with the same direction of effect for both whole blood and endometrial tissue. There was no evidence for eQTL effects for WNT4. Chromatin conformation capture provides evidence for risk SNPs interacting with the promoters of both LINC00339 and CDC4 and luciferase reporter assays suggest the risk SNP rs12038474 is located in a transcriptional silencer for CDC42 and the risk allele increases expression of CDC42. However, no effect of rs3820282 was observed in the LINC00339 expression in Ishikawa cells. Taken together, our results suggest that SNPs increasing endometriosis risk in this region act through CDC42, but further functional studies are required to rule out inverse regulation of both LINC00339 and CDC42.

Differential micro ribonucleic acid expression profiling in ovarian endometrioma with leuprolide acetate treatment

AIM

Micro ribonucleic acids (miRNAs) play an important pathological role in endometriosis. Leuprolide acetate, an analog of gonadotropin-releasing hormone, is widely used to treat endometriosis; however, the molecular mechanisms involved in endometriotic tissue regression remain unclear. We performed miRNA expression profiling of clinical ovarian endometrioma to obtain insight into the effects of leuprolide acetate treatment.

METHODS

We obtained clinical samples from nine normal eutopic endometrium, eight ovarian endometriotic, and 12 leuprolide acetate-treated endometriotic tissues. We compared the miRNA expression profiles of the three groups by performing TaqMan Array MicroRNA Card and bioinformatic analysis.

RESULTS

Two miRNAs, miR-939 and miR-154, were upregulated in endometriotic tissue and downregulated in leuprolide acetate-treated endometriotic tissue. Five miRNAs (miR-146a, miR-142-3p, miR-136*, miR-125b-1* and miR-15b*) were unchanged in endometriotic tissue but were upregulated under leuprolide acetate treatment. Ingenuity pathway analysis using predicted target genes for the seven identified miRNAs suggested the involvement of a range of pathways, including axonal guidance, bone morphogenetic protein, phosphatase and tensin homolog and nitric oxide signaling; molecular mechanisms of cancer; and the adipogenesis and signal transducer and activator of transcription 3 (STAT3) pathways.

CONCLUSIONS

To our knowledge, this is the first report profiling the miRNAs of endometrioma under leuprolide acetate treatment. The expression of seven miRNAs was modulated, concomitant with the disease state. This result gives new insight into the effects of leuprolide acetate treatment. Further investigation using quantitative reverse transcriptase-polymerase chain reaction and immunohistochemistry will allow us to validate the results of this study and to explore new therapeutic targets and biomarkers of endometriosis.

Dlx5 and Dlx6 control uterine adenogenesis during post-natal maturation: possible consequences for endometriosis

Dlx5 and Dlx6 are two closely associated homeobox genes which code for transcription factors involved in the control of steroidogenesis and reproduction. Inactivation of Dlx5/6 in the mouse results in a Leydig cell defect in the male and in ovarian insufficiency in the female. DLX5/6 are also strongly expressed by the human endometrium but their function in the uterus is unknown. The involvement of DLX5/6 in human uterine pathology is suggested by their strong downregulation in endometriotic lesions and upregulation in endometrioïd adenocarcinomas. We first show that Dlx5/6 expression begins in Müllerian ducts epithelia and persists then in the uterine luminal and glandular epithelia throughout post-natal maturation and in the adult. We then use a new mouse model in which Dlx5 and Dlx6 can be simultaneously inactivated in the endometrium using a Pgr(cre/+) allele. Post-natal inactivation of Dlx5/6 in the uterus results in sterility without any obvious ovarian involvement. The uteri of Pgr(cre/+); Dlx5/6(flox/flox) mice present very few uterine glands and numerous abnormally large and branched invaginations of the uterine lumen. In Dlx5/6 mutant uteri, the expression of genes involved in gland formation (Foxa2) and in epithelial remodelling during implantation (Msx1) is significantly reduced. Furthermore, we show that DLX5 is highly expressed in human endometrial glandular epithelium and that its expression is affected in endometriosis. We conclude that Dlx5 and Dlx6 expression determines uterine architecture and adenogenesis and is needed for implantation. Given their importance for female reproduction, DLX5 and DLX6 must be regarded as interesting targets for future clinical research.

Pathophysiological Functions of Rnd3/RhoE

Rnd3, also known as RhoE, belongs to the Rnd subclass of the Rho family of small guanosine triphosphate (GTP)-binding proteins. Rnd proteins are unique due to their inability to switch from a GTP-bound to GDP-bound conformation. Even though studies of the biological function of Rnd3 are far from being concluded, information is available regarding its expression pattern, cellular localization, and its activity, which can be altered depending on the conditions. The compiled data from these studies implies that Rnd3 may not be a traditional small GTPase. The basic role of Rnd3 is to report as an endogenous antagonist of RhoA signaling-mediated actin cytoskeleton dynamics, which specifically contributes to cell migration and neuron polarity. In addition, Rnd3 also plays a critical role in arresting cell cycle distribution, inhibiting cell growth, and inducing apoptosis and differentiation. Increasing data have shown that aberrant Rnd3 expression may be the leading cause of some systemic diseases; particularly highlighted in apoptotic cardiomyopathy, developmental arrhythmogenesis and heart failure, hydrocephalus, as well as tumor metastasis and chemotherapy resistance. Therefore, a better understanding of the function of Rnd3 under different physiological and pathological conditions, through the use of suitable models, would provide a novel insight into the origin and treatment of multiple human diseases.

Differential mRNA expression profiling in ovarian endometriotic tissue with versus without leuprolide acetate treatment

AIM

Leuprolide acetate, an analog of gonadotropin-releasing hormone (GnRH), regresses endometriotic tissue and reduces pain, resulting in clinical improvement upon treatment. The molecular mechanisms involved in the regression of endometriotic tissue, however, remain to be elucidated. In this study, we performed genome-wide gene expression profiling of clinical specimens of ovarian endometrioma to obtain insight into the effects of leuprolide acetate treatment.

METHODS

We obtained clinical samples from nine normal eutopic endometrium tissues, eight ovarian endometriotic tissues, and 12 leuprolide acetate-treated endometriotic tissues. We compared the gene expression profiles of the three groups using Affymetrix GeneChip Human genome arrays and bioinformatic analysis, including molecular concept analysis.

RESULTS

Leuprolide acetate-treated endometriotic tissue showed downregulated genes associated with the biological functions of steroid hormone regulation, cell proliferation, inflammation, and intracellular signaling. These genes included PTGDS, GRP, APLP2, PLTP, and FGFRL1. In contrast, genes upregulated by leuprolide acetate treatment were associated with cell growth inhibition and apoptosis. These genes included CARD11 and USP18.

CONCLUSIONS

These preliminary results based on GeneChip analysis suggest that leuprolide acetate treatment induces a modulation of gene expression that allows for cooperative alterations in disease state. This study gives new insight into the effects of leuprolide acetate treatment. Further investigations with quantitative reverse transcription-polymerase chain reaction and immunohistochemistry are needed to validate this study and to explore new therapeutic targets and biomarkers of endometriosis.

Towards an understanding of the molecular mechanism of endometriosis: unbalancing epithelial-stromal genetic conflict

OBJECTIVES

Despite the high incidence of endometriosis, the etiology is poorly understood. Much work has been carried out to elucidate the genetic basis of endometriosis owing to the advent of genomic analysis and new network-based analysis methods.

METHODS

This article reviews the English literature for (epi)genome-wide profiling and association studies on the pathogenesis and pathophysiology of endometriosis.

RESULTS

The characteristic 82 up- and 45 down-regulated unique genes in endometriosis included genes encoding cell cycle, growth factors, signal transduction, transcription factors, hormones, cytokines, chemokines and (pro)inflammation, proteases, cell adhesion and motility, stress response and detoxification, immune response, metabolism and others. There appear to be at least two types of genes: some genes (n = 50) may evolve mainly for the benefit of the endometrial growth, and the other genes (n = 55) evolve as a protective mechanism for the endometrial decidualization. The present review has shed new light on the overlapping genetic signatures between endometriosis development and decidualization process.

CONCLUSION

In conclusion, insufficient decidualization due to unbalancing epithelial-stromal genetic conflict may result in future endometriosis.

Biomarkers of endometriosis

BACKGROUND

Diagnosis of endometriosis is surgical through laparoscopy, which is invasive, costly and associated with potential complications.

OBJECTIVES

A non-invasive test for diagnosis of endometriosis will focus the use of laparoscopy on women who are highly suspected of having endometriosis. This review includes studies about different biomarkers for endometriosis and their potential for the non-surgical diagnosis of this disease.

METHODS

This review covers studies that investigated different biomarkers in blood or endometrium. Studies that identified definite cutoff points and evaluated the diagnostic performance of the biomarker as a blood test for endometriosis are focused on.

RESULTS/CONCLUSIONS

Some of the markers investigated showed a good specificity, none of them showed a high sensitivity. More multi-center studies involving larger numbers of patients are required to identify the most useful biomarker.

Genome-wide association study link novel loci to endometriosis

Endometriosis is a common gynecological condition with complex etiology defined by the presence of endometrial glands and stroma outside the womb. Endometriosis is a common cause of both cyclic and chronic pelvic pain, reduced fertility, and reduced quality-of-life. Diagnosis and treatment of endometriosis is, on average, delayed by 7–10 years from the onset of symptoms. Absence of a timely and non-invasive diagnostic tool is presently the greatest barrier to the identification and treatment of endometriosis. Twin and family studies have documented an increased relative risk in families. To identify genetic factors that contribute to endometriosis we conducted a two-stage genome-wide association study (GWAS) of a European cohort including 2,019 surgically confirmed endometriosis cases and 14,471 controls. Three of the SNPs we identify associated at P<5×10⁻⁸ in our combined analysis belong to two loci: LINC00339-WNT4 on 1p36.12 (rs2235529; P = 8.65×10⁻⁹, OR = 1.29, CI = 1.18–1.40) and RND3-RBM43 on 2q23.3 (rs1519761; P = 4.70×10⁻⁸, OR = 1.20, Cl = 1.13–1.29, and rs6757804; P = 4.05×10⁻⁸, OR = 1.20, Cl = 1.13–1.29). Using an adjusted Bonferoni significance threshold of 4.51×10⁻⁷ we identify two additional loci in our meta-analysis that associate with endometriosis:, RNF144B-ID4 on 6p22.3 (rs6907340; P = 2.19×10⁻⁷, OR = 1.20, Cl = 1.12–1.28), and HNRNPA3P1-LOC100130539 on 10q11.21 (rs10508881; P = 4.08×10⁻⁷, OR = 1.19, Cl = 1.11–1.27). Consistent with previously suggested associations to WNT4 our study implicate a 150 kb region around WNT4 that also include LINC00339 and CDC42. A univariate analysis of documented infertility, age at menarche, and family history did not show allelic association with these SNP markers. Clinical data from patients in our study reveal an average delay in diagnosis of 8.4 years and confirm a strong correlation between endometriosis severity and infertility (n = 1182, P<0.001, OR = 2.18). This GWAS of endometriosis was conducted with high diagnostic certainty in cases, and with stringent handling of population substructure. Our findings broaden the understanding of the genetic factors that play a role in endometriosis.

Novel estrogen-related genes and potential biomarkers of ovarian endometriosis identified by differential expression analysis

In the search for novel biomarkers of endometriosis, we selected 152 genes from the GeneLogic database based on results of genome-wide expression analysis of ovarian endometriosis, plus 20 genes related to estrogen metabolism and action. We then performed low-density array analysis of these 172 genes on 11 ovarian endometriosis samples and 9 control endometrium samples. Principal component analysis of the gene expression levels showed clear separation between the endometriosis and control groups. We identified 78 genes as differentially expressed. Based on Ingenuity pathway analysis, these differentially expressed genes were arranged into groups according to biological function. These analyses revealed that 32 differentially expressed genes are estrogen related, 23 of which have not been reported previously in connection with endometriosis. Functional annotation showed that 25 and 22 genes are associated with the biological terms "secreted" and "extracellular region", respectively. Differential expression of 4 out of 5 genes related to estrogen metabolism and action (ESR1, ESR2, PGR and BGN) was also confirmed by immunohistochemistry. Our study thus reveals differential expression of several genes that have not previously been associated with endometriosis and that encode potential novel biomarkers and drug targets.

Cloning and characterization of a venom allergen-like protein gene cluster from the pinewood nematode Bursaphelenchus xylophilus

Pinewood nematode (PWN) is the causal agent of the pine wilt disease. Previous studies have suggested that secretions from the esophageal glands of PWN play an important role in pathogenicity. A cluster of three venom allergen-like protein genes and one pseudogene, Bx-vap-1, Bx-vap-2, Bx-vap-3 and Bx-vap-P, were identified within a 3.7-kb region. Additionally, three putative modification, transport and regulatory protein genes were also detected in the same flanking region of the Bx-vap gene cluster. Genes vap-1, -2 and -3 are functional and encode three major allelic variants of PWN venom allergen-like proteins. But Bx-vap-P is an untranscribed pseudogene. Genes vap-1, -2 and -3 produce predicted products of 204, 206 and 203 amino acid residues, respectively, including the putative signal peptide sequence at the amino termini. In situ mRNA hybridization analysis showed that the transcripts of genes vap-1, -2 and -3 accumulated exclusively within the esophageal gland cells of Bursaphelenchus xylophilus.

The role of the Hoxa10/HOXA10 gene in the etiology of endometriosis and its related infertility: a review

PURPOSE

endometriosis and its associated infertility have been the object of continuous research for over a century. To understand the molecular mechanisms underlying the disease, it has become necessary to determine the aspects of its etiology that are not explained by the retrograde menstruation theory. This could in turn elucidate how various clinical and surgical treatments might affect the evolution and remission of the disease.

METHODS

this review is focused on the most recent clinical and laboratory findings regarding the association of HOXA10 with endometriosis and infertility.

RESULT

the homebox (Hox/HOX) proteins are highly conserved transcription factors that determine segmental body identities in multiple species, including humans. Hoxa10/HOXA10 is directly involved in the embryogenesis of the uterus and embryo implantation via regulation of downstream genes. Cyclical endometrial expression of Hoxa10/HOXA10, with a peak of expression occurring during the window of implantation, is observed in the adult in response to estrogen and progesterone. Women with endometriosis do not demonstrate the expected mid-luteal rise of HOXA10 expression, which might partially explain the infertility observed in many of these patients. Recent studies also demonstrated HOXA10 expression in endometriotic foci outside the Müllerian tract.

CONCLUSIONS

multiple lines of evidence suggest that the actions of the homeobox A10 (Hoxa10/HOXA10) gene could account for some aspects of endometriosis.

Deregulation of LOXL1 and HTRA1 gene expression in endometriosis

Endometriosis is a gynecologic disease characterized by the presence of endometrial tissue outside the uterine cavity. Although 15% of the female population in reproductive age is affected by endometriosis, its pathogenesis remains unclear. According to the most accepted pathogenesis hypothesis, endometrial fragments from the menstrual phase are transported through the uterine tubes to the peritoneal cavity, where they undergo implantation and growth, invading adjacent tissues. However, the establishment of the disease requires that endometrial cells present molecular characteristics favoring the onset and progression of ectopic implantation. In this investigation, we analyzed the differential gene expression profiles of peritoneal and ovarian endometriotic lesions compared to the endometrial tissue of nonaffected women using rapid subtraction hybridization (RaSH). In our study, this method was applied to samples of endometriotic lesions from affected women and to biopsies of endometrium of healthy women without endometriosis, where we could identify 126 deregulated genes. To evaluate the expression of genes found by RaSH method, we measured LOXL1, HTRA1, and SPARC genes by real-time polymerase chain reaction. Significant different expression was obtained for HTRA1 and LOXL1, upregulated in the ectopic endometrium, suggesting that these genes are involved in the physiopathology of endometriosis and may favor the viability of endometrial cells at ectopic sites.

Differential expression of microRNAs between eutopic and ectopic endometrium in ovarian endometriosis

Endometriosis, defined as the presence of endometrial tissue outside the uterus, is a common gynecological disease with poorly understood pathogenesis. MicroRNAs are members of a class of small noncoding RNA molecules that have a critical role in posttranscriptional regulation of gene expression by repression of target mRNAs translation. We assessed differentially expressed microRNAs in ectopic endometrium compared with eutopic endometrium in 3 patients through microarray analysis. We identified 50 microRNAs differentially expressed and the differential expression of five microRNAs was validated by real-time RT-PCR in other 13 patients. We identified in silico their predicted targets, several of which match the genes that have been identified to be differentially expressed in ectopic versus eutopic endometrium in studies of gene expression. A functional analysis of the predicted targets indicates that several of these are involved in molecular pathways implicated in endometriosis, thus strengthening the hypothesis of the role of microRNAs in this pathology.

Differentially expressed genes in eutopic and ectopic endometrium of women with endometriosis

OBJECTIVE

To elucidate the potential mechanisms involved in the physiopathology of endometriosis. We analyzed the differential gene expression profiles of eutopic and ectopic tissues from women with endometriosis.

DESIGN

Prospective laboratory study.

SETTING

University hospital.

PATIENT(S)

Seventeen patients in whom endometriosis was diagnosed and 11 healthy fertile women.

INTERVENTION(S)

Endometrial biopsy specimens from the endometrium of healthy women without endometriosis and from the eutopic and ectopic endometrium tissues of patients with endometriosis were obtained in the early proliferative phase of the menstrual cycle.

MAIN OUTCOME MEASURE(S)

Six paired samples of eutopic and ectopic tissue were analyzed by subtractive hybridization. To evaluate the expression of genes found by rapid subtraction hybridization methods, we measured CTGF, SPARC, MYC, MMP, and IGFBP1 genes by real-time polymerase chain reaction in all samples.

RESULT(S)

This study identified 291 deregulated genes in the endometriotic lesions. Significant expression differences were obtained for SPARC, MYC, and IGFBP1 in the peritoneal lesions and for MMP3 in the ovarian endometriomas. Additionally, significant differences were obtained for SPARC and IGFBP1 between the peritoneal and ovarian lesions. No significant differences were found for the studied genes between the control and the eutopic endometrium.

CONCLUSION(S)

This study identified 291 genes with differential expression in endometriotic lesions. The deregulation of the SPARC, MYC, MMP3, and IGFBPI genes may be responsible for the loss of cellular homeostasis in endometriotic lesions.

Hormone therapy for endometriosis and surgical menopause

BACKGROUND

Endometriosis is characterized by the presence of ectopic endometrial tissue that might lead to many distressing and debilitating symptoms. Despite available studies supporting standard hormone therapy for women with endometriosis and post-surgical menopause, there is still a concern that estrogens may induce a recurrence of the disease and its symptoms.

OBJECTIVES

This review aimed to look at pain and disease recurrence in women with endometriosis who used hormone therapy for post-surgical menopause.

SEARCH STRATEGY

We searched the Cochrane Menstrual Disorders and Subfertility Group Specialized Register (March 2008), Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2008, Issue 3), MEDLINE (1966 to March 2008), EMBASE (1980 to March 2008), and references lists of articles. Relevant journals and conference proceedings were handsearched.

SELECTION CRITERIA

Randomized controlled trials studying hormone therapy for women with endometriosis in post-surgical menopause.

DATA COLLECTION AND ANALYSIS

Review authors assessed the eligibility of trials and their quality.

MAIN RESULTS

Two studies fulfilled our inclusion criteria. One trial compared the nonstop transdermal application of 17beta-estradiol (0.05 mg/day) combined with cyclic medroxy progesterone acetate (10 mg per day) for 12 days per month in women with a conserved uterus with nonstop tibolone (2.5 mg/day). The second trial used sequential administration of estrogens and progesterone with two 22 cm(2) patches applied weekly to produce a controlled release of 0.05 mg/day. Micronized progesterone was administered orally (200 mg/day) for 14 days with a 16-day interval free of treatment. Pain and dyspareunia The first trial reported recurrence of pain in the estrogen and progesterone arm in 4/10 of women compared with 1/11 in the tibilone arm. In the latter, 4/115 women reported recurrence of pain in the treatment group compared with 0/57 patients in the no-treatment arm. Neither finding was statistically different.Confirmed recurrence or exacerbation of endometriosis This outcome was not reported in the first trial. The second found that 2/115 of the treatment group developed recurrence of endometriosis with no recurrence reported in the no-treatment group. This was not statistically significant. No woman was re-operated on in the no-treatment group compared with 2/115 in the treatment group.

AUTHORS' CONCLUSIONS

Hormone replacement therapy for women with endometriosis in post-surgical menopause could result in pain and disease recurrence. However, the evidence in the literature is not strong enough to suggest depriving severely symptomatic patients from this treatment. There is a need for more randomised controlled studies.

Neuroendocrine-immune disequilibrium and endometriosis: an interdisciplinary approach

Endometriosis, a chronic disease characterized by endometrial tissue located outside the uterine cavity, affects one fourth of young women and is associated with chronic pelvic pain and infertility. However, an in-depth understanding of the pathophysiology and effective treatment strategies of endometriosis is still largely elusive. Inadequate immune and neuroendocrine responses are significantly involved in the pathophysiology of endometriosis, and key findings are summarized in the present review. We discuss here the role of different immune mechanisms particularly adhesion molecules, proteinglycan interactions, and pro-angiogenic mediators in the development and progression of the disease. Finally, we introduce the concept of endometrial dissemination as result of a neuroendocrine-immune disequilibrium in response to high levels of perceived stress caused by cardinal clinical symptoms of endometriosis.

Comparison of c-DNA microarray analysis of gene expression between eutopic endometrium and ectopic endometrium (endometriosis)

PROBLEM

As recent studies have suggested abnormalities in the regulation of specific genes in the development of endometriosis, we investigated differentially expressed genes in endometriosis compared to endometrium.

METHOD OF STUDY

Gene expression profiles using the Atlas microarray were performed in endometriotic tissue and endometrium. Nine of the 13 genes of endometriotic tissue showed an up-regulation in relation to endometrium and four of the 13 genes a down-regulation.

RESULTS

Of the 1176 genes on the Atlas Human 1,2 array, only 13 differentially expressed identical genes were detected after repeating the gene analysis three times.

CONCLUSION

According to our c-DNA analysis some differentially expressed genes may be involved in the pathogenesis of endometriosis. An imbalance in the genes responsible for the reproductive process may lead to a decrease in embryo implantation in patients with endometriosis.

X chromosome gene expression in human tissues: male and female comparisons

About 25% of X-linked genes may escape inactivation at least to some degree. However, in vitro results from somatic cell hybrids may not reflect what happens in vivo. Therefore, we analyzed the female/male (F/M) gene fold expression ratio for 299 X-linked and 7795 autosomal genes from 11 different tissues from an existing in vivo microarray database. On average 5.1 and 4.9% of genes showed higher expression in females compared with 7.4 and 7.9% in males, respectively, for X-linked and autosomal genes. A trend was found for F/M gene fold ratios greater than 1.5 for several X-linked genes indicating overexpression in females among multiple tissues. Nine X-linked genes showed overexpression in females in at least 3 of the 11 studied tissues. Of the 9 genes, 6 were located on the short arm and 3 on the long arm of the X chromosome. Six of the 9 genes have previously been reported to escape X inactivation. However, in general, no consistent pattern was seen for the expression of X-linked genes between in vitro and in vivo systems. This study indicates that factors other than the X-inactivation process may impact on the expression of X-linked genes resulting in an overall similar gender expression for both X-linked and autosomal genes.

Cellular transcriptomics -- the next phase of endocrine expression profiling

Transcriptome analysis, or global gene expression profiling, has become a commonly used and valuable tool in both basic and clinical endocrine research. Novel endocrine regulators have 'surfaced' and greater consideration is now given to understanding function at the level of gene networks. Recent developments have shown that the transcriptome is considerably larger and more divergently expressed than was previously thought. Endocrine cells express a great variety of coding and noncoding RNAs in a highly cell-specific manner. If further value is to be taken from this research area, then steps towards defined cellular transcriptomics must be taken. New sampling techniques that utilize novel genetic models are a key first step.