Pathogenesis of Endometriosis: Focus on Adenogenesis-related Factors.

Endometriosis can be defined as the presence of the endometrium outside the uterine cavity. It affects approximately 10% of women of reproductive age and causes infertility, chronic pain, and deterioration of the quality of life. Since the identification of the disease, various pathogenetic mechanisms have been proposed, such as retrograde menstruation, coelomic metaplasia, hormonal imbalance, stem cell involvement, and alterations in epigenetic regulation. However, the underlying pathogenesis of endometriosis remains inadequately understood. Elucidation of the precise mechanism of the development and progression of endometriosis is crucial for effective treatment. This review presents the major pathogenetic theories of endometriosis based on current research studies with a major focus on the potential role of uterine factors.

Adenogenesis Factors FGF7, FGF10, FGF23, IFN-τ and HGF in Endometriosis Tissue Respect to Eutopic Endometrium: An Immunohistochemical Study.

Endometriosis is a pathological condition defined by the occurrence of endometrial glandular and stromal structures in anatomical compartments different from the uterine cavity. Endometriosis is a genetic polymorphism, estrogen-dependent inflammatory disease. This very common pathological entity causes a high level of morbidity in patients; it is also considered one of the most important causes of infertility. We and others have proposed as a pathogenetic mechanism of endometriosis a modification in the fine tuning of the processes of organogenesis of the uterus. We have correlated the immunohistochemical expression in deep endometriotic lesions and in normal endometrial tissue of several molecular factors that are implicated in the embryonic development of the uterine glands. We noticed a significant higher expression both for epithelium and stroma in the controls respect to the endometriosis samples for FGF7, FGF-10 and HGF. Interestingly, regarding FGF-23 and IFN-τ, we observed a significant higher expression in the ectopic endometrial stroma compared to the eutopic endometrium, while thepithetlium expression did not display a significant differential expression in endometriosis tissues respect to normal endometrium. The data generated support the fact that endometriosis tissues, both the epithelial and stromal component, have a different phenotype respect to the eutopic endometrium and sustain the hypothesis that alterations in the molecular mechanisms in control for adenogenesis and survival of endometrial structures are linked to the genesis and survival of endometriosis lesions outside of the uterus.

Differential Expression in Endometriosis Tissue versus Endometrium of the Uterine Adenogenesis Factors PRL-R, GH, IGF1, and IGF2.

Endometriosis is characterized by the presence of endometrial glandular and stromal structures outside the uterine cavity. It is an inflammatory estrogen dependent disease characterized by gene polymorphisms. This is a very frequent pathology and represents one of the most important causes of infertility, as well as having an important level of morbidity in patients. Recently, an alteration of the processes of organogenesis of the uterus has been proposed as a pathogenetic mechanism of endometriosis. In this article we have compared the expression in deep endometriotic lesions and in normal endometrial tissue of some of the molecular factors known to be involved in the embryonic development of the uterine glands. In detail, we found by immunohistochemistry a significant higher expression both for epithelium and stroma in the controls respect to the endometriosis samples for insulin growth factor 1 (IGF1) and IGF2, whereas for the prolactin receptor (PRL-R), this result was detected only for the epithelium. On the other hand, we found for growth hormone (GH) a significant higher expression in the epithelium of endometriosis samples respect to the controls. The correlation data generated can give indications on some of the molecular mechanisms responsible for the adenogenesis and survival of endometriosis structures outside of the uterus.

New Insights in Pathogenesis of Endometriosis.

Endometriosis is a gynecological disease characterized by the growth of endometrial glands and stroma outside the uterine cavity. The incidence of the disease is very high, there are currently no reliable early diagnostic tests, the therapies are only symptomatic and, consequently, the social impact of endometriosis is very important, also considering the related fertility problems. Despite this, the pathogenesis of endometriosis is still not fully defined. Retrograde menstruation and coelomic metaplasia are currently the most recognized pathogenetic hypotheses. Recent experimental evidences generated by our research group and by others have indicated an alteration of the fine-tuning of the female genital system developmental program during a critical window of time in the fetal life as the pathogenetic event prompting to the development of endometriosis later in life. Goal of this article is to present a revision of the recent literature about the different pathogenetic mechanisms proposed for endometriosis with particular emphasis on the embryologic theory. The possible clinical and pathological implications of these findings will be discussed.

Endometriosis: A Retrospective Analysis of Clinical Data from a Cohort of 4,083 Patients, With Focus on Symptoms.

BACKGROUND: Endometriosis is an estrogen-dependent and chronic inflammatory gynecological disease due to the presence of ectopic endometrial tissue outside the uterine cavity. This disease affects approximately 10% of the female population. In spite of its relatively high prevalence, information about its pathogenesis, diagnosis, and therapy is not complete. PATIENTS AND METHODS: We present a retrospective study performed on 4,083 patients with endometriosis, with a focus on symptoms. The archived data were analyzed investigating the distribution of symptoms among patients, the correlation of symptoms with the occupation of the patients, and finally the correlation with the other anamnestic data. Statistical associations between the data for all cases were then considered separately. RESULTS: Chronic fatigue syndrome and dyspareunia were confirmed as being among the main symptoms of endometriosis, together with bowel disorders. On the other hand, we registered a low occurrence of urinary disorders and even of chronic pelvic pain, which is usually considered among the main symptoms of endometriosis. We found an increase in incidence of symptoms starting from the age group 25-29 years up to 40-44 years and, subsequently, a significant decrease in the group aged 55-59 years. For all the symptoms analyzed, we found a higher incidence in employers, graduates and freelancers. Finally, we found a protective effect of the number of gestations on chronic fatigue syndrome. CONCLUSION: This in-depth study on such a vast cohort of affected patients clarifies some important aspects on the complex symptomatology of this still enigmatic disease. In particular, the study highlights the symptoms most closely related to endometriosis which will help speed up the diagnostic process of patients suffering from this pathology.

Endometriosis: A Retrospective Analysis on Diagnostic Data in a Cohort of 4,401 Patients.

BACKGROUND/AIM: Endometriosis is a gynecological estrogen-dependent inflammatory disease due to ectopic endometrial tissue and often associated with pelvic pain. Despite its high prevalence, there are still uncertainties about its pathogenesis, diagnosis, and therapy. PATIENTS AND METHODS: This study presents a retrospective study conducted on 4,401 endometriosis patients, 584 of which underwent laparoscopic procedures. The archived data about clinical signs, magnetic resonance imaging (MRI) results, topography of the endometriosis lesions (obtained via laparoscopy) associated diseases, sample analysis and histological findings were analyzed. Next, the statistical associations between the information for each case, provided by these diagnostic tools were determined. RESULTS: MRI is the most sensitive and specific diagnostic system for ovarian lesions, but poor in sensitivity and specificity for deep endometriosis lesions and not indicated for peritoneal lesions which remain the exclusive prerogative of laparoscopy. Clinical signs are essential for diagnosing deep lesions. The Ca125 and Ca19.9 markers have a poor reliability and their negativity in symptomatic patients has no clinical value, while in positive cases it could probably be used as a monitoring parameter. CONCLUSION: The results generated will help provide an accurate picture of the topography and distribution of endometriotic lesions. Correlation analyses between the data generated by the clinical-instrumental examinations and those on the site of the disease identified by laparoscopy, allow to define the predictive value of the clinical-instrumental signs in the diagnosis and localization of endometriotic disease.

Methylation analysis of HOXA10 regulatory elements in patients with endometriosis.

OBJECTIVE: The pathogenesis of endometriosis is still mysterious, being retrograde menstruation and coelomic metaplasia the most accepted hypotheses. Recently, it has been proposed that endometriosis is caused by fine-tuning alterations of the female genital system development during the foetal life and that in utero exposition to endocrine disruptors can be one of the factors causing the disease, possibly acting on the methylation status of the genome. In this study, we have evaluated the methylation status of HOXA10 gene regulation regions in a cohort of 22 endometriosis patients respect to a control group of 6 healthy women. RESULTS: The methylation study was carried out on three CpG islands, previously described hypermethylated in the endometrium of endometriosis patients and include 22 CpG sites, 21 CpG sites and 10 CpG sites, respectively identified through the online platform MethPrimer. The analysis did not find significant differences between patients with endometriosis and healthy control individuals. These results confirm previous studies on genome wide methylation analysis in endometriosis patients. Therefore, other epigenetically altered genes should be considered more related to the pathogenesis of endometriosis.

Histological and Immunohistochemical Characterization of a Case of Endometriosis in a Guinea Pig (Cavia tschudii).

Endometriosis is a chronic gynecological disease characterized by the ectopic proliferation of endometrial tissue outside of the uterine cavity. The pathogenesis of this disease is still obscure, and Sampson's theory of retrograde menstruation is still the most widely accepted explanation. Endometriosis in animals has been so far described not only in baboons and a rhesus macaque but also in dogs and horses that are nonmenstruating animals. In this article, we report the histological and immunohistochemical characterization of the first case of ovarian cystic endometriosis and adenomyosis in a guinea pig. The case presented supports the hypothesis that endometriosis is a disease not at all related to the phenomenon of retrograde menstruation but is a consequence of some alterations in the morphogenesis of the female genital system and therefore it could be found in any mammal. We suggest considering endometriosis among the other pathological phenotypes in animals displaying ovarian and uterine alterations and having a history of difficulties in conceiving.

New evidence in endometriosis.

Endometriosis is a recurrent and benign gynecological disorder characterized by the presence of endometrial tissue outside the cavity of the uterus. It is one of the most common diseases in the gynecological field, affecting about 10% of the female population in reproductive age. Despite this, its pathogenesis is still unacknowledged, there is a lack of early diagnostic markers and current therapies are only symptomatic. Considering the relevant health problems caused by endometriosis, all new information on this disease may have important clinical implications. The aim of this article is to summarize the latest advances in the pathogenesis, diagnosis and therapy of endometriosis that have recently been proposed by our research group. The possible clinical implications of these findings will be discussed.

Anti-mullerian hormone is expressed by endometriosis tissues and induces cell cycle arrest and apoptosis in endometriosis cells.

BACKGROUND: The anti-mullerian hormone (AMH) is a member of the transforming growth factor ß (TGF-ß) superfamily, which is responsible of the regression of the mullerian duct. AMH is expressed in the normal endometrium, where, acting in a paracrine fashion, negatively regulates cellular viability. Our objective was to evaluate the in vitro effects of the treatment with AMH of endometriosic cells. METHODS: AMH expression in human endometriosis glands was evaluated by immunohistochemistry. RT-PCR has been used to quantify the expression levels of AMH and AMH RII isoforms, as well as of cytochrome P450 in both endometriosis epithelial and stromal cells Effects of AMH and AMH-cleaved treatment in endometriosis cells were evaluated by flow-cytometry analysis. Finally, it has been evaluated the effect of plasmin-digested AMH on cytochrome P450 activity. RESULTS: AMH and AMH RII isoforms, as well as cytochrome P450, were expressed in both endometriosis epithelial and stromal cells. Treatment of endometriosis stromal and epithelial cell growth with AMH was able to induce a decrease in the percentage of cells in S phase and increase percentage of cells in G1 and G2 phase; coherently, decreased cell viability and increased percentage of cells death fraction was observed. The plasmin-digested AMH was able to suppress most of the cytochrome P450 activity, causing an increase of pre-G1 phase and of apoptosis induction treating with plasmin-digested AMH in both cell lines, most marked in the epithelial cells. CONCLUSIONS: The data produced suggest a possible use of AMH as therapeutic agents in endometriosis.

Transcriptional profiling of endometriosis tissues identifies genes related to organogenesis defects.

Endometriosis is a common benign pathology, characterised by the presence of endometrial tissue outside the endometrial cavity with a prevalence of 10-15% in reproductive-aged women. The pathogenesis is not completely understood, and several theories have been proposed to explain the aetiology. Our group has recently described the presence of ectopic endometrium in a consistent number of human female foetuses analysed by autopsy, reinforcing the hypothesis that endometriosis may be generated by defects during the organogenesis of the female reproductive trait. Herein, in order to identify, at molecular level, changes involved in the disease, we compared the transcriptional profiling of ectopic endometrium with the corresponding eutopic one. Statistical analyses lead us to identify some genes specifically deregulated in the ectopic endometrium, that are involved in gonad developmental process or in wound healing process. Among them, we identified BMP4 and GREM1. BMP4 was never associated before to endometriosis and is involved in the mesoderm-Müllerian duct differentiation. GREM1 is needed for the initial step of the ureter growth and perhaps could possibly be involved in Müller ducts differentiation. These molecules might be related to the endometriosis aetiology since we showed that their expression is not related to the menstrual cycle phase both at RNA and at protein levels. These data support the theory that embryological defects could be responsible of the endometriosis generation.

Embryologic origin of endometriosis: analysis of 101 human female fetuses.

The etiology of endometriosis, a gynecological disease characterized by the presence of endometrial glands and stroma outside the uterine cavity, is still unknown. Our research group has recently demonstrated the presence of ectopic endometrium in human female fetuses at different gestational ages. In this manuscript we describe four new cases of fetal endometriosis found among a series of 52 female fetuses analyzed at autopsy. The anatomical localization of this ectopic endometrium, and its histological and immunohistochemical characteristics are depicted. We suggest that endometriosis is caused by dislocation of primitive endometrial tissue outside the uterine cavity during organogenesis. The clinical and pathological implications of these findings are discussed.

New evidence of the presence of endometriosis in the human fetus.

The aetiology of endometriosis, a gynaecological disease defined by the histological presence of endometrial glands and stroma outside the uterine cavity, is still open to debate. Research has recently found evidence for endometriosis in human female fetuses at different gestational ages. This paper reports a new case of fetal endometriosis in a 25-week female fetus, deceased due to placental pathology, from a series of 13 female fetuses analysed at autopsy. The exact anatomical localization of this misplaced endometrium, as well as its histopathological and immunohistochemical characteristics are illustrated. The case suggests that endometriosis can be caused by dislocation of primitive endometrial tissue outside the uterine cavity during organogenesis.

Endometriosis: new concepts in the pathogenesis.

Endometriosis is a gynaecological disease defined by the histological presence of endometrial glands and stroma outside the uterine cavity. Though there are several theories, research scientists remain unsure as to the definitive cause(s) of endometriosis. Considering the relevant health problems caused by endometriosis, all new information on the pathogenesis of this disease, may have important clinical implications. Goal of this article is to summarize the latest advances in the pathogenesis of endometriosis, with particular emphasis on the embryological theory, that has been recently re-proposed. The possible clinical implications of these findings will be discussed.

Pre-natal exposure of mice to bisphenol A elicits an endometriosis-like phenotype in female offspring.

Endometriosis is a chronic gynecological disease characterized by the growth of endometrial tissue outside the uterine cavity. Exposure to endocrine disruptors during critical period of development causes long-lasting effects, being the genital system one of the targets. This study describes the effects on female genital system caused by developmental exposure to the endocrine-disrupting chemical bisphenol A (BPA) during pre- and peri-natal development in mice. To this end, timed pregnant Balb-C mice were treated from day 1 of gestation to 7 days after delivery with BPA (100, or 1000 microg/kg/day). After delivery, pups were held for 3 months; then, pelvic organs were analyzed in their entirety and livers of both pups and moms were studied for the presence of BPA. We found in the adipose tissue surrounding the genital tracts of a consistent number of treated animals, endometriosis-like structure with the presence of both glands and stroma and expressing both estrogen receptor and HOXA-10. Moreover, cystic ovaries, adenomatous hyperplasia with cystic endometrial hyperplasia and atypical hyperplasia were significantly more frequent in treated animals respect to the controls. Finally, BPA was found in the livers of exposed moms and female offspring. In conclusion, we describe for the first time an endometriosis-like phenotype in mice, elicited by pre-natal exposition to BPA. This observation may induce to thoroughly reconsider the pathogenesis and treatment of endometriosis, considering the high incidence of endometriosis and the problems caused by associated infertility.

Ectopic endometrium in human foetuses is a common event and sustains the theory of müllerianosis in the pathogenesis of endometriosis, a disease that predisposes to cancer.

BACKGROUND: Endometriosis is a gynecological disease defined by the histological presence of endometrial glands and stroma outside the uterine cavity. Women with endometriosis have an increased risk of different types of malignancies, especially ovarian cancer and non-Hodgkin's lymphoma. Though there are several theories, researchers remain unsure as to the definitive cause of endometriosis. Our objective was to test the validity of the theory of müllerianosis for endometriosis, that is the misplacing of primitive endometrial tissue along the migratory pathway of foetal organogenesis METHODS: We have collected at autopsy 36 human female foetuses at different gestational age. We have performed a morphological and immunohistochemical study (expression of oestrogen receptor and CA125) on the pelvic organs of the 36 foetuses included en-block and totally analyzed. RESULTS: In 4 out of 36 foetuses we found presence of misplaced endometrium in five different ectopic sites: in the recto-vaginal septum, in the proximity of the Douglas pouch, in the mesenchimal tissue close to the posterior wall of the uterus, in the rectal tube at the level of muscularis propria, and in the wall of the uterus. All these sites are common location of endometriosis in women. CONCLUSION: We propose that a cause of endometriosis is the dislocation of primitive endometrial tissue outside the uterine cavity during organogenesis.

Endometriosis: pathogenesis, diagnosis, therapy and association with cancer (review).

Endometriosis is a painful reproductive and immunological disease afflicting about 7-10% of women worldwide. It is one of the most frequent benign gynaecological diseases; however, little is known about the pathogenetic processes leading to the development and maintenance of this disease and the currently available therapeutic strategies are unsatisfactory. The goal of this article is to review the most recent advancements in the pathogenesis, diagnosis and therapy of this disease. The risk for cancer among women with endometriosis will be analyzed in light of the most recent epidemiological and functional studies focused on this disease.