Endometriosis: pathogenesis and treatment

A systematic review on endometriosis during pregnancy: diagnosis, misdiagnosis, complications and outcomes

BACKGROUND

Traditionally, pregnancy was considered to have a positive effect on endometriosis and its painful symptoms due not only to blockage of ovulation preventing bleeding of endometriotic tissue but also to different metabolic, hormonal, immune and angiogenesis changes related to pregnancy. However, a growing literature is emerging on the role of endometriosis in affecting the development of pregnancy and its outcomes and also on the impact of pregnancy on endometriosis. The present article aims to underline the difficulty in diagnosing endometriotic lesions during pregnancy and discuss the options for the treatment of decidualized endometriosis in relation to imaging and symptomatology; to describe all the possible acute complications of pregnancy caused by pre-existing endometriosis and evaluate potential treatments of these complications; to assess whether endometriosis affects pregnancy outcome and hypothesize mechanisms to explain the underlying relationships.

METHODS

This systematic review is based on material searched and obtained via Pubmed and Medline between January 1950 and March 2015. Peer-reviewed, English-language journal articles examining the impact of endometriosis on pregnancy and vice versa were included in this article.

RESULTS

Changes of the endometriotic lesions may occur during pregnancy caused by the modifications of the hormonal milieu, posing a clinical dilemma due to their atypical appearance. The management of these events is actually challenging as only few cases have been described and the review of available literature evidenced a lack of formal estimates of their incidence. Acute complications of endometriosis during pregnancy, such as spontaneous hemoperitoneum, bowel and ovarian complications, represent rare but life-threatening conditions that require, in most of the cases, surgical operations to be managed. Due to the unpredictability of these complications, no specific recommendation for additional interventions to the routinely monitoring of pregnancy of women with known history of endometriosis is advisable. Even if the results of the published studies are controversial, some evidence is suggestive of an association of endometriosis with spontaneous miscarriage, preterm birth and small for gestational age babies. A correlation of endometriosis with placenta previa (odds ratio from 1.67 to 15.1 according to various studies) has been demonstrated, possibly linked to the abnormal frequency and amplitude of uterine contractions observed in women affected. Finally, there is no evidence that prophylactic surgery would prevent the negative impact of endometriosis itself on pregnancy outcome.

CONCLUSIONS

Complications of endometriosis during pregnancy are rare and there is no evidence that the disease has a major detrimental effect on pregnancy outcome. Therefore, pregnant women with endometriosis can be reassured on the course of their pregnancies although the physicians should be aware of the potential increased risk of placenta previa. Current evidence does not support any modification of conventional monitoring of pregnancy in patients with endometriosis.

The oil-resin of the tropical rainforest tree Copaifera langsdorffii reduces cell viability, changes cell morphology and induces cell death in human endometriotic stromal cultures

OBJECTIVES

The hormonal treatment for endometriosis frequently fails to completely eradicate endometriotic implants. A new therapeutic treatment is needed. This study investigates the in-vitro effect of Copaifera langsdorffii oil-resin on human eutopic and ectopic endometrium stromal cell cultures (EuESCs and EctESCs).

METHODS

A nanocomposite system containing the copaiba oil-resin (NanoCOR) was developed and acute toxicity test was performed. Endometrial stromal cells (ESCs) from non-endometriotics controls (CESCs), EuESCs and EctESCs were isolated and treated with different concentrations of NanoCOR, at different time intervals to evaluate its effect on cell morphology, proliferation, viability, necrosis and apoptosis induction.

KEY FINDINGS

When treated with 50 μg/ml of NanoCOR, the morphology of EctESCs changed, as the actin microfilaments were disorganized, disassembled or disrupted. Moreover, at 24 h of treatment with NanoCOR, the EctESCs viability was inhibited, and a significant number of these cells underwent apoptosis. In EuESCs, these effects were observed only at 48 h. Finally, the treatment of EctESCs with NanoCOR increased the lactate dehydrogenase release into the extracellular medium more than in EuESCs.

CONCLUSIONS

Our data indicate that NanoCOR has a greater impact on the behaviour of human endometriotic stromal cells than on the eutopic endometrium stromal cells, supporting the idea that NanoCOR should be further investigated as a novel and valuable alternative to treat endometriosis.

Elagolix, a novel, orally bioavailable GnRH antagonist under investigation for the treatment of endometriosis-related pain

Suppression of estrogen production and reduction of menstrual blood flow are the mainstays of medical treatment of endometriosis-related pain and have been traditionally achieved by methods such as combined hormonal contraception, progestins and GnRH analogs, all with comparable efficacies, though different side-effect profiles. Elagolix is the frontrunner among an emerging class of GnRH antagonists, which unlike their peptide predecessors has a nonpeptide structure resulting in its oral bioavailability. Phase I and II clinical trials have demonstrated safety of elagolix and its efficacy in partial and reversible suppression of ovarian estrogen production resulting in improvements in endometriosis-related pain. Phase III clinical trials are currently underway and elagolix may become a valuable addition to the armamentarium of pharmacological agents to treat endometriosis-related pain.

Magnetic resonance imaging evidence for perineural spread of endometriosis to the lumbosacral plexus: report of 2 cases

Sciatic nerve endometriosis (EM) is a rare presentation of retroperitoneal EM. The authors present 2 cases of catamenial sciatica diagnosed as sciatic nerve EM. They propose that both cases can be explained by perineural spread of EM from the uterus to the sacral plexus along the pelvic autonomie nerves and then further distally to the sciatic nerve or proximally to the spinal nerves. This explanation is supported by MRI evidence in both cases. As a proof of concept, the authors retrieved and analyzed the original MRI studies of a case reported in the literature and found a similar pattern of spread. They believe that the imaging evidence of their institutional cases together with the outside case is a very compelling indication for perineural spread as a mechanism of EM of the nerve.

The Risk of Epithelial Ovarian Cancer of Women With Endometriosis May be Varied Greatly if Diagnostic Criteria Are Different: A Nationwide Population-Based Cohort Study

This article aims to test the hypothesis that the risk of epithelial ovarian cancer (EOC) in women with endometriosis might be changed by enrolling different population. A nationwide 14-year historic cohort study using the National Health Insurance Research Database (NHIRD) of Taiwan and the Registry for Catastrophic Illness Patients was conducted. A total of 239,385 women aged between 20 and 51 years, with at least 1 gynecologic visit after 2000, were analyzed. Cases included women with a diagnosed endometriosis, which was established along a spectrum from at least 1 medical record of endometriosis (recalled endometriosis) to tissue-proved ovarian endometriosis (n = X). Controls included women without any diagnosis of endometriosis (n = 239,385 - X). We used Cox regression, and computed hazard ratios (HRs) with 95% confidence intervals (95% CI) to determine the risk of EOC in patients. The EOC incidence rates (IRs, per 10,000 person-years) of women with endometriosis ranged from 1.90 in women with recalled endometriosis to 18.70 in women with tissue-proved ovarian endometrioma, compared with those women without any diagnosis of endometriosis (0.77-0.89), contributing to crude HRs ranging from 2.59 (95% CI, 2.09-3.21; P < 0.001) to 24.04 (95% CI, 17.48-33.05; P < 0.001). After adjustment for pelvic inflammatory disease, infertility, Charlson co-morbidity index, and age, adjusted HRs were ranged from the lowest of 1.90 (95% CI, 1.51-2.37; P < 0.001) in recalled endometriosis to the highest of 18.57 (95% CI, 13.37-25.79; P < 0.001) in tissue-proved ovarian endometrioma, which was inversely related to the prevalence rate of endometriosis (from the highest of 30.80% in recalled endometriosis to the lowest of 1.54% in tissue-proved ovarian endometrioma). The risk of EOC in women with endometriosis varied greatly by different criteria used. Women with endometriosis might have a more apparently higher risk than those reported by systematic review and meta-analysis.

Endometriosis and ovarian cancer: potential benefits and harms of screening and risk-reducing surgery

Although endometriosis is well recognized as a benign gynecologic condition, its association with ovarian cancer (OVCA) has frequently been reported. Review articles on this topic are voluminous, yet there seems to be no consensus as to whether endometriosis is truly a precursor of OVCA and whether any screening or risk-reducing surgery should be instituted, on the basis of our current knowledge. In this review, published data are compiled and critically appraised. Through this critical appraisal, it seems clear that the strongest evidence seems to come from prevalence data. This type of data also suggests a reduced risk of certain histotypes (mainly type II) of OVCA in women with endometriosis. This may explain the rather moderate increase in risk as shown in epidemiologic studies. Even with this moderate increase in OVCA risk, caution should be exercised because of apparent bias in favor of publication of positive results, extensive heterogeneities among prevalence estimates, and inverse relationship between estimates and sizes of the studies. Many molecular studies are conflicting, and earlier studies showing molecular aberrations involved in genomic instability and mutation that enable malignant transformation are not replicated in later studies. Given the low incidence of OVCA and the rather moderate increase in risk of mostly type I tumors, screening seems to be ill-advised, and risk-reducing surgery such as salpingectomy with or without oophorectomy does not seem to yield any substantial benefit to women with endometriosis.

Medical treatment for adenomyosis and/or adenomyoma

Uterine adenomyosis and/or adenomyoma is characterized by the presence of heterotopic endometrial glands and stroma within the myometrium, >2.5 mm in depth in the myometrium or more than one microscopic field at 10 times magnification from the endometrium-myometrium junction, and a variable degree of adjacent myometrial hyperplasia, causing globular and cystic enlargement of the myometrium, with some cysts filled with extravasated, hemolyzed red blood cells, and siderophages. Hysterectomy is a "gold standard" and definitive therapy for uterine adenomyosis, and many cases of adenomyosis have been diagnosed by pathological review retrospectively. As such, the diagnosis of adenomyosis is difficult, and this subsequently results in difficulty in the management of these patients, especially those who are symptomatic but have a strong desire to preserve their uterus. In our previous review, we found that the use of uterine-sparing surgery in the management of uterine adenomyosis and/or adenomyoma is still controversial, although some data support its feasibility. Conservative treatment is still needed in the group of patients that requires preservation of fertility and improvement of quality of life. However, studies focusing on the topic of medical treatment for adenomyosis are rare. In this article, current knowledge regarding the use of medical therapy for uterine adenomyosis, partly based on the understanding of endometriosis, is reviewed.

The involvement of osteopontin and matrix metalloproteinase- 9 in the migration of endometrial epithelial cells in patients with endometriosis

BACKGROUND

Endometriosis, which shares certain characteristics with cancers, may cause abnormal expression of proteins involved in cell migration. Endometrial epithelial cells (EECs) are believed to play an important role in endometriotic migration. The aim of this study was to investigate the relationship between the expression of osteopontin (OPN) and matrix metalloproteinase-9 (MMP-9) in endometriotic migration.

METHODS

We performed primary culture of EECs and investigated the expression of OPN and MMP-9 in EECs regulated by 17beta-estradiol (E2). OPN-specific siRNA interference was used to down-regulate OPN and to explore the corresponding change in MMP-9 expression. Real-time RT-PCR, western blot analysis and flow cytometry were used to determine the expression levels of OPN and MMP-9. Gelatin zymography was performed to observe the enzymatic activity of MMP-9 in conditioned media. Transwell and wound scratch assays were performed to investigate the migration ability of EECs.

RESULTS

The expression levels of OPN and MMP-9 in normal EECs (NEECs) were inferior to those in EECs from patients with endometriosis (EEECs). The expression levels of OPN and MMP-9 from stage III/IV EEECs and secretory-phase EECs were higher than those of stage I/II EEECs or proliferative-phase EECs. The expression levels of OPN and MMP-9 in EEECs were increased by E2 treatment and remarkably decreased by siRNA interference. Active MMP-9 expression increased with E2 treatment and decreased with siRNA treatment in EEECs compared with the same treatments in NEECs. The migratory abilities of EEECs were enhanced after cells were treated with E2; in contrast, these abilities were reduced by siRNA interference. In NEECs, active MMP-9 and cellular migration abilities were only minimally influenced by E2 and siRNA treatment.

CONCLUSIONS

The present study suggests that the up-regulation of MMP-9 via activation of OPN induced by estrogen may correlate with the migration of endometrial epithelial cells in patients with endometriosis.

Nuclear magnetic resonance metabolomic profiling of urine provides a noninvasive alternative to the identification of biomarkers associated with endometriosis

OBJECTIVE

To investigate whether urine metabolomic profile can be used to identify biomarkers associated to endometriosis.

DESIGN

Prospective study. For each subject, a urine sample was collected after overnight fasting and before surgery.

SETTING

University medical center.

PATIENT(S)

The clinical cohort included 45 endometriosis patients, diagnosed at early (n = 6) and advanced (n = 39) stages of the disease, and 36 healthy women. All women underwent diagnostic laparoscopy to visually confirm the presence or absence of endometriotic lesions.

INTERVENTION(S)

Metabolomic profiling of urine samples based on (1)H-nuclear magnetic resonance (NMR) spectroscopy in combination with statistical approaches.

MAIN OUTCOME MEASURE(S)

Comparative identification of metabolites present in urine from endometriosis patients and healthy women.

RESULT(S)

The urine metabolomic profile of endometriosis patients exhibited higher concentrations of N(1)-methyl-4-pyridone-5-carboxamide, guanidinosuccinate, creatinine, taurine, valine, and 2-hydroxyisovalerate and decreased concentrations of lysine compared with healthy women. Most of these metabolites are involved in inflammation and oxidative stress processes. These pathophysiologic events had been previously described to be present in ectopic endometrial proliferation foci.

CONCLUSION(S)

Overall, the results demonstrate the potential of (1)H-NMR-based metabolomics, a rapid and noninvasive approach, to identify metabolic changes associated to endometriosis in urine samples. This information could be useful to get a better understanding of the pathogenesis of endometriosis, thus providing support to the noninvasive diagnosis of this pathology.

IL-17A Contributes to the Pathogenesis of Endometriosis by Triggering Proinflammatory Cytokines and Angiogenic Growth Factors

Endometriosis is a chronic, inflammatory disease characterized by the growth of endometrial tissue in aberrant locations outside the uterus. Neoangiogenesis or establishment of new blood supply is one of the fundamental requirements of endometriotic lesion survival in the peritoneal cavity. IL-17A is emerging as a potent angiogenic and proinflammatory cytokine involved in the pathophysiology of several chronic inflammatory diseases such as rheumatoid arthritis and psoriasis. However, sparse information is available in the context of endometriosis. In this study, we demonstrate the potential importance of IL-17A in the pathogenesis and pathophysiology of endometriosis. The data show a differential expression of IL-17A in human ectopic endometriotic lesions and matched eutopic endometrium from women with endometriosis. Importantly, surgical removal of lesions resulted in significantly reduced plasma IL-17A concentrations. Immunohistochemistry revealed localization of IL-17A primarily in the stroma of matched ectopic and eutopic tissue samples. In vitro stimulation of endometrial epithelial carcinoma cells, Ishikawa cells, and HUVECs with IL-17A revealed significant increase in angiogenic (vascular endothelial growth factor and IL-8), proinflammatory (IL-6 and IL-1β), and chemotactic cytokines (G-CSF, CXCL12, CXCL1, and CX3CL1). Furthermore, IL-17A promoted tubulogenesis of HUVECs plated on Matrigel in a dose-dependent manner. Thus, we provide the first evidence, to our knowledge, that endometriotic lesions produce IL-17A and that the removal of the lesion via laparoscopic surgery leads to the significant reduction in the systemic levels of IL-17A. Taken together, our data show a likely important role of IL-17A in promoting angiogenesis and proinflammatory environment in the peritoneal cavity for the establishment and maintenance of endometriosis lesions.

Enhanced epithelial to mesenchymal transition (EMT) and upregulated MYC in ectopic lesions contribute independently to endometriosis

BACKGROUND

Epithelial to mesenchymal transition (EMT) is a process in which epithelial cells lose polarity and cell-to-cell contacts and acquire the migratory and invasive abilities of mesenchymal cells. These abilities are thought to be prerequisites for the establishment of endometriotic lesions. A hallmark of EMT is the functional loss of E-cadherin (CDH1) expression in epithelial cells. TWIST1, a transcription factor that represses E-cadherin transcription, is among the EMT inducers. SNAIL, a zinc-finger transcription factor, and its close relative SLUG have similar properties to TWIST1 and are thus also EMT inducers. MYC, which is upregulated by estrogens in the uterus by an estrogen response cis-acting element (ERE) in its promoter, is associated with proliferation in endometriosis. The role of EMT and proliferation in the pathogenesis of endometriosis was evaluated by analyzing TWIST1, CDH1 and MYC expression.

METHODS

CDH1, TWIST1, SNAIL and SLUG mRNA expression was analyzed by qRT-PCR from 47 controls and 74 patients with endometriosis. Approximately 42 ectopic and 62 eutopic endometrial tissues, of which 30 were matched samples, were collected during the same surgical procedure. We evaluated TWIST1 and MYC protein expression by immunohistochemistry (IHC) in the epithelial and stromal tissue of 69 eutopic and 90 ectopic endometrium samples, of which 49 matched samples were analyzed from the same patient. Concordant expression of TWIST1/SNAIL/SLUG and CDH1 but also of TWIST1 and MYC was analyzed.

RESULTS

We found that TWIST1, SNAIL and SLUG are overexpressed (p < 0.001, p = 0.016 and p < 0.001) in endometriosis, while CDH1 expression was concordantly reduced in these samples (p < 0.001). Similar to TWIST1, the epithelial expression of MYC was also significantly enhanced in ectopic endometrium compared to eutopic tissues (p = 0.008). We found exclusive expression of either TWIST1 or MYC in the same samples (p = 0.003).

CONCLUSIONS

Epithelial TWIST1 is overexpressed in endometriosis and may contribute to the formation of endometriotic lesions by inducing epithelial to mesenchymal transition, as CDH1 was reduced in ectopic lesions. We found exclusive expression of either TWIST1 or MYC in the same samples, indicating that EMT and proliferation contribute independently of each other to the formation of endometriotic lesions.

The co-expression of GPER and Gankyrin in ovarian endometriosis and its correlation with the rASRM stages

OBJECTIVE

The aim of this study was to examine the expression of G protein-coupled estrogen receptor (GPER) and Gankyrin in ovarian endometriosis, analyze their clinicopathological significance, and investigate their correlation.

METHODS

Quantitative real-time polymerase chain reaction and Western blot were performed to testify mRNA and protein expression of GPER and Gankyrin in ovarian endometriosis. Immunohistochemical staining (streptavidin-peroxidase method) was conducted to determine the expression and distribution of GPER and Gankyrin protein in matched ectopic and eutopic endometrium of endometriosis and normal endometrium. We also investigated their associations with rASRM stages and the correlation between the two proteins.

RESULTS

GPER and Gankyrin were found overexpressed in ectopic endometrium of endometriosis compared with either its eutopic counterpart or endometrium from normal patients. The immunohistochemical analysis also revealed that higher expression was observed in eutopic endometrium with or without endometriosis during proliferative phase in comparison to secretory phase. These two proteins were positively correlated with the stages of endometriosis. Moreover, a significant positive correlation was found between GPER and Gankyrin both in ectopic and eutopic endometrium of the ovarian endometriosis.

CONCLUSION

GPER and Gankyrin might be implicated in the hormonal regulation of endometriosis and be associated with the severity of endometriosis. In addition, GPER and Gankyrin were found to be positively correlated, which could possibly serve as novel therapeutic targets for this disease.

Pathogenetic Mechanisms of Deep Infiltrating Endometriosis

Endometriosis is a benign gynecologic disease, affecting women of reproductive age associated with chronic pelvic pain, dysmenorrhea, dyspareunia and infertility. Ovarian endometrioma (OMA), superficial peritoneal endometriosis (SPE), and deep infiltrating endometriosis (DIE) are, till now, recognized as major phenotypes. The discussion is to know whether they share the same pathogenetic mechanisms. Till today, DIE is recognized as the most severe clinical form of endometriosis and has a complex clinical management. The DIE lesions have been considered in the present article, without distinguishing between the anterior (bladder) or the posterior (vagina, uterosacral ligaments, rectum, and ureter) compartment. The present knowledge indicates that hormonal function (estrogen and progesterone receptors) and immunological factors, such as peritoneal macrophages, natural killer cells, and lymphocytes, are critically altered in DIE. The aggressive behavior of DIE may be explained by the highly decreased apoptosis (nuclear factor kappa-light-chain-enhancer of activated B cells [NF-kB], B-cell lymphoma 2 [Blc-2], and anti-Mullerian hormone) and by the increased proliferation activity related to oxidative stress (NF-kB, reactive oxygen species, extracellular regulated kinase (ERK), advanced oxidation protein product). Invasive mechanisms are more expressed (matrix metalloproteinases and activins) in DIE in comparison to the OMA and SPE. Correlated with the increased invasiveness are the data on very high expression of neuroangiogenesis (nerve growth factor, vascular endothelial growth factor, and intercellular adhesion molecule) genes in DIE. Therefore, at the present time, several of the DIE pathogenetic features result specific in comparison to other endometriosis phenotypes, pleading for the existence of a specific entity. These evidence of specific pathogenetic features of DIE may explain the more severe symptomatology related to this form of endometriosis and suggest possible future target medical treatments.

Leptin promotes human endometriotic cell migration and invasion by up-regulating MMP-2 through the JAK2/STAT3 signaling pathway

Despite evidence that leptin may play a role in the pathogenesis of endometriosis, the specific function of leptin in the migration and invasion of endometriotic cells is not well characterized. In this study, we investigated the effect of leptin on the migration, invasion and matrix metalloproteinase (MMP) expression levels of human endometriotic cells. We found that leptin stimulated the migration and invasion of endometriotic cells (11Z, 12Z and 22B) in a dose-dependent manner. Leptin receptor (ObR) siRNA significantly inhibited the migration and invasion induced by leptin in 11Z and 12Z cells. Leptin-induced migration and invasion were significantly attenuated by pretreatment with SB-3CT, a specific gelatinase (MMP-2 and MMP-9) inhibitor. In addition, leptin-induced increases in the mRNA and protein expression and enzyme activity of MMP-2 in 11Z and 12Z cells. Selectively inhibiting MMP-2 using siRNA and an inhibitor (GM6003), impaired the ability of leptin to stimulate the migration and invasion of endometriotic cells, suggesting that MMP-2 plays an essential role in leptin-induced migration and invasion. Janus Kinase 2/Signal Transducer and Activator of Transcription 3 (JAK2/STAT3) inhibitor (AG490) significantly inhibited the migration, invasion and MMP-2 expression induced by leptin in endometriotic cells. Furthermore, the Extracellular signal-Regulated Kinase inhibitor PD98059 neutralized the migration and invasion promoting effects of leptin. Taken together, these results suggest that leptin may contribute to the migration and invasion abilities of endometriotic cells via the up-regulation of MMP-2 through an ObR-dependent JAK2/STAT3 signaling pathway.

Should we abstain from treating women with endometriosis using menopausal hormone therapy, for fear of an increased ovarian cancer risk?

Women suffering from endometriosis often have an early menopause, resulting in severe menopausal symptoms and an increased risk of osteoporosis. They are therefore candidates for menopausal hormone therapy (MHT). Unfortunately, MHT may increase the risk of endometriosis recurrence. Moreover, endometriosis patients are at increased risk of ovarian cancer, which may be further enhanced by MHT use. It is unknown, however, whether MHT more frequently increases type I (low-grade serous tumors), which seem to be increased when endometriosis is present, or type II (the more aggressive high-grade serous) tumors. We propose the following decision-making algorithm for endometriosis patients considering MHT. Those who have been treated with bilateral salpingo-oophorectomy, and in whom there is no residual endometriotic disease, can probably be treated using MHT without risk of endometriosis recurrence or fear of ovarian cancer. For women with significant, residual endometriosis lesions, the benefit may outweigh the risks, when menopause is reached before the age of 45 years or when severe symptoms are present.

The Impact of Endometriosis across the Lifespan of Women: Foreseeable Research and Therapeutic Prospects

In addition to estrogen dependence, endometriosis is characterized by chronic pelvic inflammation. The impact of the chronic pelvic inflammatory state on other organ systems and women's health is unclear. Endometriosis associated chronic inflammation and potential adverse health effects across the lifespan render it imperative for renewed research vigor into the identification of novel biomarkers of disease and therapeutic options. Herein we propose a number of opportunities for research and development of new therapeutics to address the unmet needs in the treatment of endometriosis per se and its ancillary risks for other diseases in women across the lifespan.

Fertility preservation in women with endometriosis: for all, for some, for none?

The increasing confidence with the techniques of oocyte and ovarian cortex freezing has prompted their potential use for patient categories other than those at risk of early menopause due to cancer treatments. Women affected by every iatrogenic or pathologic condition known to compromise ovarian function severely have been considered as potential candidates for fertility preservation. Among them, women with endometriosis may represent a particularly suitable group since they are at increased risk of premature ovarian exhaustion and about half of them will experience infertility. Based on the currently available notions on the intricate relationships between endometriosis, infertility and damage to the ovarian reserve, we speculate that fertility preservation may be of interest for women with endometriosis, in particular for those with bilateral unoperated endometriomas and for those who previously had excision of unilateral endometriomas and require surgery for a contralateral recurrence. Young age at diagnosis may be an independent but pivotal additional factor to be taken into consideration in the balance of the pros and cons of fertility preservation. On the other hand, we argue against the introduction of fertility preservation for endometriosis in routine clinical practice. To date, only few cases have been reported and there are insufficient data for robust cost-utility analyses. It is noteworthy that endometriosis is a relatively common disease and systematically including affected women in a fertility preservation program would have profound clinical, logistic and financial effects. More clinical data and in-depth economic analysis are imperative prior to recommending its routine use.

The Targeted Delivery of Interleukin 4 Inhibits Development of Endometriotic Lesions in a Mouse Model

Endometriosis is caused by the displacement of endometrium outside the uterus contributing heavily to infertility and debilitating pelvic pain. Ectopic adhesion and growth are believed to occur under the influence of a favorable hormonal environment and immunological factors. The objective of this study is to analyze the effect of a targeted therapy with an antibody-based pharmacodelivery of interleukin 4 (F8-IL4) in a mouse model of experimentally induced endometriosis. Endometriosis-like lesions were induced in Balb/c mice. The animals were treated intravenously with F8-IL4 or with untargeted IL4 (KSF-IL4). Twelve days after disease induction, the lesions were isolated. A significant reduction in the number of total lesions/mouse and in the total volume of lesions/mouse was observed in mice treated with F8-IL4 compared to controls (P = .029 and P = .006, respectively), while no difference was found between KSF-IL4-treated mice and their controls. Gene expression was evaluated by quantitative real-time polymerase chain reaction. Expression of genes involved in cell adhesion, extracellular matrix invasion, and neovascularization was significantly downregulated in F8-IL4-treated mice compared to their controls (integrin β1: P = .02; metalloproteinase [MMP] 3: P = .02; MMP9: P = .04; vascular endothelial growth factor: P = .04). Gene expression of inflammatory cytokines (tumor necrosis factor α, IL1β, IL1α, and IL6) did not vary in the ectopic lesions isolated from F8-IL4-treated mice compared to their controls. Immunohistochemistry demonstrated a significantly reduced expression of E-cadherin and β-catenin in the lesions of mice treated with F8-IL4. Our results show that the antibody-mediated targeted delivery of IL4 inhibits the development of endometriosis in a syngeneic mouse model by likely impairing adhesion, invasion, and vascularization of the ectopic endometrium.

Initiation of GnRH agonist treatment on 3-5 days postoperatively in endometriosis patients: a randomized controlled trial

Seventy patients with stage III or IV endometriosis were randomly assigned to 2 groups after conservative surgery. Group O (n = 35) received 3 cycles of a 28-day gonadotropin-releasing hormone agonist (GnRH-a) treatment (goserelin, 3.6 mg) starting 3-5 days postoperatively. Group M (n = 35) received the same treatment starting on days 1-5 of menstruation. Groups were further subdivided according to add-back treatment. Pre- and posttreated levels of estradiol (E2 ), follicle stimulating hormone (FSH), and luteinizing hormone (LH) and visual analog scale (VAS), Kupperman menopausal index (KMI), and bone mineral density (BMD) scores were recorded. The incidence of uterine bleeding was assessed. In both groups, serum levels of E2 , FSH, and LH and VAS scores decreased significantly after treatment. Spotting was the most frequent bleeding pattern. During cycle 1, the bleeding time in group M was much longer that than that in group O (P =.001), and the bleeding rate in group M was significantly higher than that in group O (P =.024, RR = 1.185). In patients with stage III or IV endometriosis, the efficacy of GnRH-a initiated 3-5 days postoperatively was equivalent to that of GnRH-a initiated on days 1-5 of menstruation. Female patients who initiated GnRH-a treatment 3-5 days postoperatively experienced less uterine bleeding during the first cycle of treatment.

The endometriotic tissue lining the internal surface of endometrioma: hormonal, genetic, epigenetic status, and gene expression profile

Ovarian endometriomas are found in a consistent proportion of patients with endometriosis and are associated with a more severe form of the disease. The endometriotic tissue lining the inside of the endometrioma has been extensively studied over the years mostly for the need to compare the molecular and cellular characteristics of eutopic and ectopic endometria. Several aspects of hormonal regulation, response to local inflammation, carcinogenesis, and modifications of the local environment have been investigated in order to characterize also the processes associated with peritoneal endometriosis. In this review, we have summarized the current knowledge of pathophysiology of endometrioma, with a particular focus on the cellular components lining the internal surface of the cyst in order to provide a comprehensive overview of the hormonal, genetic, epigenetic, and gene expression profiles of this essential part of the cyst.

Exploring the Relationship between Endometriomas and Infertility

Several clinical and epidemiological studies demonstrated an association between endometriosis and infertility. A role in the genesis of infertility may be played by endometriomas, which may interfere with ovulation or damage ovarian tissue. Unlike peritoneal implants, the availability of an accurate noninvasive sonographic diagnosis facilitates the investigation of endometrioma associated infertility. The laparoscopic excision of an endometrioma relieves the ovary from the damage caused by the cyst itself, which may be progressive over time, but at the same time is associated with a detrimental effect on ovarian reserve and with high rates of postoperative endometrioma recurrence. Therefore, the management of endometrioma-related infertility should not be based upon surgery alone, but upon a combination of surgery, with a refinement of the operating technique, long-term oral contraceptive, in vitro fertilization and oocyte cryopreservation.

Diagnostic potential of peritoneal fluid biomarkers of endometriosis

Endometriosis is defined as the presence of endometrial glands and stroma outside the uterus, in different parts of the peritoneal cavity. It affects up to 10% of reproductive-age women and up to 50% of women with infertility. Surgical diagnosis of endometriosis is still the gold standard, with no diagnostic biomarkers available. Medical therapies target the symptoms and not the disease itself, and surgical treatment cannot prevent recurrence. As peritoneal fluid reflects the altered peritoneal microenvironment of endometriosis patients, it can provide a wealth of information on pathophysiological processes and potential biomarkers. This report reviews the molecular biomarkers identified in peritoneal fluid over the last 5 years and discusses their potential applications for diagnosis, prognosis and drug therapy.

Replication and meta-analysis of previous genome-wide association studies confirm vezatin as the locus with the strongest evidence for association with endometriosis

STUDY QUESTION

Is it possible to replicate the genetic association of single nucleotide polymorphisms (SNPs) rs13394619, rs4141819, rs7739264, rs17694933 and rs10859871 in five genetic loci previously identified as associated with endometriosis in an Italian Caucasian population?

SUMMARY ANSWER

SNP rs10859871 near the vezatin (VEZT) gene was found to be significantly associated with endometriosis in general while SNPs rs17694933 and rs4141819 were associated with Stage III/IV and ovarian disease, respectively.

WHAT IS KNOWN ALREADY

Endometriosis represents a complex disease in which the phenotypic manifestations are influenced by both genetic and environmental factors. Recent genome-wide association studies (GWASs) have allowed to identify some SNPs associated with the predisposition to the disease. A meta-analysis published in 2014 combined results from GWAS and replication studies showing that of the nine loci found to be associated with the disease in at least one of the studies, six (rs7521902, rs1270667, rs13394619, rs7739264, rs1537377 and rs10859871) remained genome-wide significant while two others (rs1250248 and rs4141819) showed borderline genome-wide significant association with more severe disease.

STUDY DESIGN, SIZE, DURATION

Allele frequencies of selected SNPs (rs13394619, rs4141819, rs7739264, rs17694933 and rs10859871) were investigated in 305 women with laparoscopically proven endometriosis, 285 laparoscopic controls and 2425 healthy, blood donor controls from the general population. A meta-analysis with previous data was also conducted.

PARTICIPANTS/MATERIALS, SETTING, METHODS

A total of 590 women who underwent endoscopic surgery were enrolled in the study and a blood sample was collected. After DNA extraction, genotype was obtained using Taq-Man pre-designed assay. Genotype data from healthy blood donor women were obtained from an existing genotype bank.

MAIN RESULTS AND THE ROLE OF CHANCE

A statistically significant association with endometriosis was found for SNP rs10859871, close to the VEZT gene, compared with both general population [odds ratio (OR) = 1.43, 95% confidence interval (CI): 1.20-1.71, P = 6.9 × 10(-5)] and laparoscopic controls (OR = 1.58, 95% CI: 1.24-2.02, P = 2.1 × 10(-4)). Meta-analysis with previous data confirmed the rs10859871 SNP as that with the strongest evidence for association with endometriosis (OR = 1.19, 95% CI: 1.15-1.24, P = 7.9 × 10(-20)). A further meta-analysis conducted using data from Stage III-IV endometriosis resulted in stronger genome-wide significant effect sizes for four out of the five SNPs tested.

LIMITATIONS, REASONS FOR CAUTION

The inability to confirm all previous demonstrated associations considering all stages of endometriosis may be due to a lack of statistical power and differences in the definition of cases included.

WIDER IMPLICATIONS OF THE FINDINGS

The associations with the SNPs identified so far have been obtained with a relatively small sample size supporting a limited heterogeneity across the various datasets. This represents an important advance in the identification of genetic markers of this disease.

STUDY FINDING/COMPETING INTERESTS

No funding to declare. The authors have no competing financial interests in relation to the content of this research paper.

How to Manage Bowel Endometriosis: The ETIC Approach

A panel of experts in the field of endometriosis expressed their opinions on management options in a 35-year-old patient desiring pregnancy with a history of previous surgery for endometrioma and bowel obstruction symptoms. Many questions that this paradigmatic patient may pose to the clinician are addressed, and various clinical scenarios are discussed. A decision algorithm derived from this discussion is proposed as well.

Possible Role of α1-Antitrypsin in Endometriosis-Like Grafts From a Mouse Model of Endometriosis

Previous study indicated that bleeding into the peritoneum may accelerate inflammatory response in endometriosis-like grafts in mice. To identify changes in protein levels in the grafts from mice that underwent unilateral ovariectomy (uOVX), which causes bleeding from ovarian arteries and vein, the grafts were generated by injecting a suspension of human endometrial cells in BALB/c nude female mice, and protein profile changes were compared with non-uOVX control mice. The level of α1-antitrypsin (α1-AT) decreased in grafts from nude mice that underwent uOVX. The levels of phosphorylated Akt, mammalian target of rapamycin, S6K, regulatory factors for cell survival, and of phosphorylated nuclear factor κB, an inflammatory mediator, were higher in endometriosis-like grafts from the uOVX group than from the control. The grafts were mostly comprised of stromal cells. The bioactivity of α1-AT was assessed by investigating cytokine expression in protease-activated receptor (PAR) 1/2 agonists-stimulated stromal cells. The PARs promoted the expression of interleukin 8 (IL-8), but treatment with α1-AT blocked IL-8 expression dose dependently. Knocking down α1-AT expression increased the constitutive IL-6, IL-8, and cyclooxygenase 2 expression as well as PAR1 agonist-stimulated IL-6 expression. These findings support the notion that decreased α1-AT protein in the grafts constituted with human endometrial cells in mice may have exacerbated inflammation in endometriosis-like grafts, suggesting the possible involvement of α1-AT in the pathophysiology of endometriosis.

Minireview: nuclear receptor coregulators of the p160 family: insights into inflammation and metabolism

Nuclear receptor coactivators (NCOAs) are multifunctional transcriptional coregulators for a growing number of signal-activated transcription factors. The members of the p160 family (NCOA1/2/3) are increasingly recognized as essential and nonredundant players in a number of physiological processes. In particular, accumulating evidence points to the pivotal roles that these coregulators play in inflammatory and metabolic pathways, both under homeostasis and in disease. Given that chronic inflammation of metabolic tissues ("metainflammation") is a driving force for the widespread epidemic of obesity, insulin resistance, cardiovascular disease, and associated comorbidities, deciphering the role of NCOAs in "normal" vs "pathological" inflammation and in metabolic processes is indeed a subject of extreme biomedical importance. Here, we review the evolving and, at times, contradictory, literature on the pleiotropic functions of NCOA1/2/3 in inflammation and metabolism as related to nuclear receptor actions and beyond. We then briefly discuss the potential utility of NCOAs as predictive markers for disease and/or possible therapeutic targets once a better understanding of their molecular and physiological actions is achieved.

Anti-inflammatory, antiangiogenic, and apoptosis-inducing activity of DLBS1442, a bioactive fraction of Phaleria macrocarpa, in a RL95-2 cell line as a molecular model of endometriosis

DLBS1442 is a bioactive fraction extracted from the fruit of the native Indonesian plant, Phaleria macrocarpa (Scheff.) Boerl (Thymelaceae). This bioactive fraction is a potential treatment for dysmenorrhea and endometriosis. The present study investigated the pharmacological action of DLBS1442 in endometrial cells. The effect of various doses of DLBS1442 (0–200 μg/mL) over 24 hours was studied using the human endometrial RL95-2 cell line to observe its effect on angiogenesis, cell migration, estrogen and progesterone receptor levels, the eicosanoid pathway, cell viability, and apoptosis. The impact of DLBS1442 on nuclear factor kappa B (NFκB) and the eicosanoid pathway was also studied through its marker gene expression using a quantitative real-time polymerase chain reaction method. DLBS1442 showed an ability to inhibit angiogenesis and cell migration in a dose-dependent manner. At a dose of 100 μg/mL, DLBS1442 increased the cell population in sub-G1 phase from 7% to 34%. DLBS1442 also significantly downregulated the estrogen receptor level and upregulated the progesterone receptor level. Further, it inhibited the eicosanoid signaling pathway by reducing the NFκB transcription level and subsequent reduction of inducible nitric oxide synthase. A dose-dependent decrease in viability and increased apoptosis in RL95-2 cells were also evident after exposure to DLBS1442, where the IC₅₀ was obtained at around 100 μg/mL. In conclusion, DLBS1442 is a potential agent for alleviating symptoms of endometriosis via its antiangiogenic, anti-inflammatory, and proapoptotic activity.

Endometriosis and perceived stress: impact of surgical and medical treatment

BACKGROUND

The aim of the study was to investigate the levels of perceived stress in a group of women with a long-term history of endometriosis in conjunction with surgical and/or medical treatments.

METHODS

A clinical trial was conducted at the Department of Molecular and Developmental Medicine, University of Siena, in collaboration with a non-profit association of women with endometriosis, A.P.E. Onlus. Patients (n = 204) with a previous diagnosis of endometriosis (for at least 3 years) were included in this study. Each patient completed a semi-structured questionnaire and a validated scale to assess perceived stress, the Perceived Stress Scale (PSS) by e-mail.

RESULTS

The study showed that in women with a long-term history of endometriosis, the level of perceived stress was increased by repeated surgical treatments and reduced by some medical treatments. The median PSS value was 23 (range 9-36) and 30.6% of the study population were included in the highest stress category (>26). The highest levels were found in patients who had undergone the most surgery. The use of progestins was associated with a lower perceived stress (p = 0.004) than in the patients treated with gonadotropin-releasing hormones.

CONCLUSIONS

Long-term endometriosis has a relevant impact on perceived stress, in particular in those undergoing repeated surgery.

Analysis of WNT4 polymorphism in Chinese Han women with endometriosis

Endometriosis is a complex disease that is influenced by genetic and environmental factors. In endometriosis, WNT4 plays a likely role owing to its biological functions. In this study, the TaqMan allelic discrimination technique was used to investigate the relationship between endometriosis and four single nucleotide polymorphisms in WNT4 (rs7521902 [A/C], rs16826658 [G/T], rs7515106 [C/T] and rs2235529 [A/G]) in Chinese Han women. A total of 646 patients with endometriosis and 766 normal controls were recurited. Regression analyses revealed that rs2235529 was a risk locus for endometriosis (P = 1.80E-03, OR, 95% CI = 1.311, 1.129 to 1.522), particularly in patients with stage III and IV disease. No significant association was found between endometriosis and rs7521902 (A/C), rs16826658 (G/T), or rs7515106 (C/T). For each of the four single nucleotide polymorphisms, no association was found between patients with endometriosis-related infertility or primary infertility and the controls. The results demonstrated that WNT4 rs2235529 is associated with endometriosis in Chinese Han women, which may result in aberrant expression of WNT4, leading to the pathogenesis of endometriosis.

Association of common variations of the E-cadherin with endometriosis

Endometriosis is a polygenic and multifactorial disease. E-cadherin (CDH1) gene encodes an epithelial cell-cell adhesion glycoprotein that modulates a wide variety of processes, including cell polarization, migration and cancer metastasis. Decreased expression of CDH1 in epithelial cells in peritoneal endometriosis has been reported in advanced stages of endometriotic lesions. We investigated the CDH1 -160C/A and +54C/T variations with susceptibility to endometriosis in an Iranian population. In this case-control study, 149 patients with endometriosis (stages I-IV) and 151 healthy women as controls were included. Genotyping was performed using PCR-RFLP method. A p value of <0.05 was considered statistically significant. The CDH1 + 54TT genotype was significantly lower (p = 0.012; OR = 0.30, 95% CI: 0.12-0.77) in the patients (11.6%) than the control group (26.7%). The CDH1 + 54T allele was significantly lower (p = 0.001; OR = 0.55, 95% CI: 0.38-0.77) in the cases (35.7%) compared with the control group (50.3%). No association was found between CDH1 - 160C/A polymorphism and endometriosis. The CDH1 +54C/T was associated with susceptibility to endometriosis in Iranian population, and +54T allele may have a protective role in progression of endometriosis.

Endometriosis in a patient with mayer-rokitansky-küster-hauser syndrome

Objective. To report a case of Mayer-Rokitansky-Küster-Hauser syndrome (MRKH) in which there were two nonfunctional rudimentary uteruses with the presence of ovarian endometrioma, corroborating that there are valid alternative theories to the existence of endometriosis, rather than Sampson's theory alone, such as the coelomic metaplasia theory. Design. A case report. Setting. A tertiary referral center, which is also a university hospital. Patient. A fifteen-year-old patient with MRKH syndrome and endometriosis. Intervention. Laparoscopic approach for diagnostic confirmation and treatment of the endometrioma. Results. Evidence of endometriosis in a patient with no functional uterus. Conclusions. This case report and a few others that are available in the literature reinforce the possibility that coelomic metaplasia could be the origin of endometriosis. Patients with müllerian agenesis and pelvic pain should be carefully evaluated, and the presence of pelvic endometriosis should not be excluded.

Iron overload-modulated nuclear factor kappa-B activation in human endometrial stromal cells as a mechanism postulated in endometriosis pathogenesis

OBJECTIVE

To evaluate the effect of iron overload on nuclear factor kappa-B (NF-κB) activation in human endometrial stromal cells (ESCs).

DESIGN

Experimental study.

SETTING

University hospital research laboratory.

PATIENT(S)

Ten healthy women.

INTERVENTION(S)

Isolated ESCs from endometrial biopsies were incubated with 50 μM FeSO(4) or vehicle. The NF-κB inhibitor [5-(p-fluorophenyl)-2-ureido] thiophene-3-carboxamide (TPCA-1), which inhibits IKKβ, the kinase of IκBα (inhibitory protein of NF-κB), was used to prevent iron overload-stimulated NF-κB changes in ESCs.

MAIN OUTCOME MEASURE(S)

NF-κB activation was assessed by p65:DNA-binding activity immunodetection assay. IκBα, p65, and intercellular adhesion molecule (ICAM)-1 proteins expression was evaluated by Western blots. ESC soluble ICAM (sICAM)-1 secretion was measured by ELISA using conditioned medium.

RESULT(S)

Iron overload increased p65:DNA-binding activity and decreased IκBα and p65 cytoplasmic expression in ESCs after 30 minutes of incubation as compared with the basal condition. ESC ICAM-1 expression and sICAM-1 secretion were higher after 24 hours of iron overload treatment than in the absence of treatment. TPCA-1 prevented the iron overload-induced increase of p65:DNA binding and IκBα degradation.

CONCLUSION(S)

Iron overload activates IKKβ in ESCs, stimulating the NF-κB pathway and increasing ICAM-1 expression and sICAM-1 secretion. These results suggest that iron overload induces a proendometriotic phenotype on healthy ESCs, which could participate in endometriosis pathogenesis and development.

Endometriosis and ovarian cancer

Endometriosis is the leading cause of morbidity among premenopausal women and the complex pathogenesis of this disease remains controversial despite extensive research. This disease represents one of the most common gynecological problems. It is generally believed that this disease is due primarily to retrograde menstruation or transplantation of shed endometrium. Based on overwhelming data, ovarian endometrioma is considered a neoplastic process, since most endometriosis-associated ovarian carcinoma occur in the presence of atypical ovarian endometriosis. A study comparing patients with typical epithelial ovarian cancer with endometriosis-associated ovarian cancer demonstrated that the patients with the latter disease strongly differ in both biological and histological characteristics. The prevelance of this disease is not completely established, but approximately 15 percent of women suffer from this disease. In addition, we know about the possible links between endometriosis and cancer for almost 100 years. Despite clear evidence revealing that endometriosis increases ovarian cancer risks, it is possible that it may not affect disease progression after the appearance of ovarian cancer. However, despite clear evidence revealing that endometriosis increases ovarian cancer risk, our knowledge of the risk factors is far from established. In our review, we focused on the most recent approaches including possible biomarkers and genetic approaches.

Leisure and occupational physical activity at different ages and risk of endometriosis

OBJECTIVE

Cohort and case-control studies have suggested that adult physical activity (PA) may lower endometriosis risk and improve symptoms, but evidence is still controversial. To add information on leisure and occupational PA impact, if any, on endometriosis risk, we have analyzed data from a small case-control study conducted in Milan (Italy).

STUDY DESIGN

Ninety cases and 90 controls (median age 35 years, range 18-76) were compared. Endometriosis was laparoscopically diagnosed within the year before interview. Information on demographic variables, menstrual and reproductive history, occupational and recreational physical activity was collected.

RESULTS

A consistent protective effect emerged between leisure PA and endometriosis risk. For <2-4 and ≥5h/week (reference no PA), the estimated odds ratios (ORs) were, respectively: 0.36 (95% CI 0.18-0.74) and 0.83 (95% CI 0.27-2.53) as regards PA in early adolescence; 0.31 (95% CI 0.15-0.63) and 0.78 (95% CI 0.25-2.38) as regards PA in teenage years; 0.34 (95% CI 0.12-0.94) and 0.33 (95% CI 0.08-1.28) for PA in adulthood. However, no significant trend was seen according to hours spent in leisure PA. Occupational PA did not show statistical significant differences among different types or across age classes.

CONCLUSIONS

These results suggest that leisure PA in early adolescence, teenage years and adulthood may, to some extent, decrease the risk of endometriosis. In the interpretation of these results, however, the role of potential biases cannot be totally ruled out.