Redefining endometriosis: is deep endometriosis a progressive disease?

Distribution of smooth muscle actin and collagen in superficial peritoneal endometriotic lesions varies from the surrounding microenvironment

RESEARCH QUESTION

Do different subtypes of superficial peritoneal endometriotic lesions exist, based on the presence and morphology of smooth muscle, collagen fibres and immune cell populations?

DESIGN

A retrospective cohort study of 24 patients, from across the menstrual cycle, with surgically and histologically confirmed endometriosis. Immunofluorescence was used to delineate the CD10 stromal area of lesions (n = 271 lesions from 67 endometriotic biopsies), and then smooth muscle actin (SMA) positive tissue and immune cell populations (CD45+ and CD68+) were quantified within and adjacent to these lesions. Second harmonic generation microscopy was used to evaluate the presence and morphology of type-1 collagen fibres within and surrounding lesions.

RESULTS

Overall, immune cell numbers and the area of SMA and collagen within endometriotic lesions tended to be low, but a spectrum of presentations significantly varied, particularly in the adjacent tissue microenvironment, based on lesion locations, the morphology of endometriotic gland profiles, or both. Lesions in which collagen fibres formed well aligned capsules around the CD10+ stromal border were identified compared with lesions in which collagen fibre distribution was random. Considerable inter- and intra-patient variability in the morphology of SMA and collagen was observed within and surrounding lesions.

CONCLUSION

These data demonstrate considerable diversity in the presence of immune cells and morphology of SMA and collagen within, but even more so, surrounding endometriotic lesions, even within individual patients. This heterogeneity, especially within individual patients, presents a challenge to incorporating these cell and tissue types into any new endometriosis classification systems or prognostic approaches.

Deep Infiltrating Endometriosis in Adolescence: Early Diagnosis and Possible Prevention of Disease Progression

Endometriosis has a prevalence of 10% worldwide in premenopausal women. Probably, endometriosis begins early in the life of young girls, and it is commonly diagnosed later in life. The prevalence of deep infiltrating endometriosis (DIE) in adolescence is currently unknown due to diagnostic limits and underestimation of clinical symptoms. Dysmenorrhea is a common symptom in adolescents affected by DIE, often accompanied by dyspareunia and chronic acyclic pelvic pain. Ultrasonography-either performed transabdominal, transvaginal or transrectal-should be considered the first-line imaging technique despite the potential for missed diagnosis due to early-stage disease. Magnetic resonance imaging should be preferred in the case of virgo patients or when ultrasonographic exam is not accepted. Diagnostic laparoscopy is deemed acceptable in the case of suspected DIE not responding to conventional hormonal therapy. An early medical and/or surgical treatment may reduce disease progression with an immediate improvement in quality of life and fertility, but at the same time, painful symptoms may persist or even recur due to the surgery itself. The aim of this narrative review is to report the prevalence of DIE in adolescents, describe the pathogenetic theories and discuss the management in adolescent women, including the challenging road to diagnosis and the treatment alternatives.

Learning endometriosis phenotypes from patient-generated data

Endometriosis is a systemic and chronic condition in women of childbearing age, yet a highly enigmatic disease with unresolved questions: there are no known biomarkers, nor established clinical stages. We here investigate the use of patient-generated health data and data-driven phenotyping to characterize endometriosis patient subtypes, based on their reported signs and symptoms. We aim at unsupervised learning of endometriosis phenotypes using self-tracking data from personal smartphones. We leverage data from an observational research study of over 4000 women with endometriosis that track their condition over more than 2 years. We extend a classical mixed-membership model to accommodate the idiosyncrasies of the data at hand, i.e., the multimodality and uncertainty of the self-tracked variables. The proposed method, by jointly modeling a wide range of observations (i.e., participant symptoms, quality of life, treatments), identifies clinically relevant endometriosis subtypes. Experiments show that our method is robust to different hyperparameter choices and the biases of self-tracking data (e.g., the wide variations in tracking frequency among participants). With this work, we show the promise of unsupervised learning of endometriosis subtypes from self-tracked data, as learned phenotypes align well with what is already known about the disease, but also suggest new clinically actionable findings. More generally, we argue that a continued research effort on unsupervised phenotyping methods with patient-generated health data via new mobile and digital technologies will have significant impact on the study of enigmatic diseases in particular, and health in general.

Morphological and immunohistochemical characterization of spontaneous endometriosis in rhesus macaques (Macaca mulatta)

Several cases of spontaneous endometriosis in middle-aged to old rhesus macaques (Macaca mulatta) from the breeding colony of the German Primate Center were thoroughly characterized with regards to anatomical distribution and macroscopic appearance, histological differentiation and immunohistochemical profile including somatic markers, hormonal receptors, and proliferation indices. More than half of the examined animals (five of nine) were directly related to one breeding male, supporting a strong genetic predisposition. Histologically, four different types of endometriotic lesions, depending on the degree of ectopic endometrial gland and stromal differentiation (well differentiated, purely stromal, mixed differentiation, poorly differentiated), could be constantly identified within all animals. Immunohistochemistry (IHC) of cytokeratin (CK), vimentin, smooth muscle actin (SMA), desmin, estrogen (ER), and progesterone (PR) receptors as well as of the nuclear proteins Ki67 and p53 revealed varying staining patterns in the four different types of endometriosis differentiation and compared to normal endometrium. Purely stromal, mixed, or poorly differentiated lesions, especially, showed additional cytokeratin-positive stromal cells, whereas epithelial cells of endometriosis with mixed or poor differentiation increasingly expressed mesenchymal markers (vimentin, SMA). Hormonal receptor and Ki67 expression in well-differentiated endometriotic lesions mostly reflected that of normal endometrial tissue according to the cyclic phase of the animal, while the expression gradually diminished with decreasing grade of differentiation. However, increased nuclear accumulations of p53 antigen could only be continuously detected in epithelial cells of mixed or poorly differentiated endometriosis. Altogether, these findings support the pathogenetic theory of coelomic metaplasia, since the expression profiles of somatic markers in less differentiated forms closely resembled that of mesothelial cells. Thus, the four different histological types of endometriosis might display subsequent grades of differentiation in the course of time, with poorly differentiated types representing newly formed, immature lesions and well-differentiated types being older, fully differentiated forms, rather than being the outcome of dedifferentiation processes.

Trauma and endometriosis. A review. May we explain surgical phenotypes and natural history of the disease?

OBJECTIVE

The study was performed to evaluate whether trauma is an initial event of development of endometriosis.

METHOD

Using Medline database from January 1960 up to December 2014, a systematic review was made of all published studies using the keywords trauma, healing, injury, infection, hyperperistaltism, stretch and endometriosis, adenomyosis and trauma. Studies and review articles written in French and/or in English related to the topic were included and reviewed independently by two authors.

RESULTS

The role of trauma is well-established for endometriotic lesions diagnosed in surgical scars. Various traumas including delivery, uterine curettage or incision, intraperitoneal hemorrhage, or occult pelvic inflammatory diseases could be involved to explain other localizations of the disease. Many data suggested that the healing process, particularly growth factors and the associated estrogen production, may facilitate the implantation and the growth of ectopic endometrial cells. After the initial, a traumatic event, the phenotype of the disease would depend on the tissue in which the endometriotic lesion grows.

CONCLUSIONS

The present literature review may support a potential role of a trauma as an initial event of endometriosis.

Kisspeptin/Kisspeptin Receptor System in the Ovary

Kisspeptins are a family of neuropeptides that are critical for initiating puberty and regulating ovulation in sexually mature females via the central control of the hypothalamic-pituitary-gonadal axis. Recent studies have shown that kisspeptin and its receptor kisspeptin receptor (KISS1R) are expressed in the mammalian ovary. Convincing evidence indicates that kisspeptins can activate a wide variety of signals via its binding to KISS1R. Experimental data gathered recently suggest a putative role of kisspeptin signaling in the direct control of ovarian function, including follicular development, oocyte maturation, steroidogenesis, and ovulation. Dysregulation or naturally occurring mutations of the kisspeptin/KISS1R system may negatively affect the ovarian function, leading to reproductive pathology or female infertility. A comprehensive understanding of the expression, actions, and underlying molecular mechanisms of this system in the human ovary is essential for novel approaches to therapeutic and diagnostic interventions in reproductive diseases and infertility.

A new concept of endometriosis and adenomyosis: tissue injury and repair (TIAR)

Pelvic endometriosis, deeply infiltrating endometriosis and uterine adenomyosis share a common pathophysiology and may be integrated into the physiological mechanism and new nosological concept of 'tissue injury and repair' (TIAR) and may, in this context, just represent the extreme of a basically physiological, estrogen-related mechanism that is pathologically exaggerated in an extremely estrogen-sensitive reproductive organ. The acronym TIAR describes a fundamental and apparently ubiquitous biological system that becomes operative in mesenchymal tissues following tissue injury and, upon activation, results in the local production of estradiol. Endometriosis and adenomyosis are caused by trauma. In the spontaneously developing disease, chronic uterine peristaltic activity or phases of hyperperistalsis induce, at the endometrial-myometrial interface near the fundo-cornual raphe, microtraumatisations, with activation of the TIAR mechanism. With ongoing traumatisations, such sites of inflammation might accumulate and the increasingly produced estrogens interfere in a paracrine fashion with ovarian control over uterine peristaltic activity, resulting in permanent hyperperistalsis and a self-perpetuation of the disease process. Overt autotraumatisation of the uterus with dislocation of fragments of basal endometrium into the peritoneal cavity and infiltration of basal endometrium into the depth of the myometrial wall ensues. In most cases of endometriosis/adenomyosis a causal event early in the reproductive period of life must be postulated, rapidly leading to archimetral hyperestrogenism and uterine hyperperistalsis. In late premenopausal adenomyosis such an event might not have occurred. However, as indicated by the high prevalence of the disease, it appears to be unavoidable that, with time, chronic normoperistalsis throughout the reproductive period of life accumulates to the same extent of microtraumatisation. With activation of the TIAR mechanism followed by chronic inflammation and infiltrative growth, endometriosis/adenomyosis of the younger woman and premenopausal adenomyosis share in principal the same pathophysiology.

Identification of susceptibility genes for peritoneal, ovarian, and deep infiltrating endometriosis using a pooled sample-based genome-wide association study

Characterizing genetic contributions to endometriosis might help to shorten the time to diagnosis, especially in the most severe forms, but represents a challenge. Previous genome-wide association studies (GWAS) made no distinction between peritoneal endometriosis (SUP), endometrioma (OMA), and deep infiltrating endometriosis (DIE). We therefore conducted a pooled sample-based GWAS and distinguished histologically confirmed endometriosis subtypes. We performed an initial discovery step on 10-individual pools (two pools per condition). After quality control filtering, a Monte-Carlo simulation was used to rank the significant SNPs according to the ratio of allele frequencies and the coefficient of variation. Then, a replication step of individual genotyping was conducted in an independent cohort of 259 cases and 288 controls. Our approach was very stringent but probably missed a lot of information due to the Monte-Carlo simulation, which likely explained why we did not replicate results from “classic” GWAS. Four variants (rs227849, rs4703908, rs2479037, and rs966674) were significantly associated with an increased risk of OMA. Rs4703908, located close to ZNF366, provided a higher risk of OMA (OR = 2.22; 95% CI: 1.26–3.92) and DIE, especially with bowel involvement (OR = 2.09; 95% CI: 1.12–3.91). ZNF366, involved in estrogen metabolism and progression of breast cancer, is a new biologically plausible candidate for endometriosis.

The effect of combined surgical-medical intervention on the progression of endometriosis in an adolescent and young adult population

STUDY OBJECTIVE

To evaluate the effect of combined surgical-medical treatment on endometriosis progression in adolescents as measured by disease stage.

DESIGN

Retrospective chart review.

SETTING

Two academic medical centers.

PARTICIPANTS

Sequential cases of young women identified on chart review with chronic pelvic pain unresponsive to dysmenorrheal treatment who underwent initial laparoscopy for diagnosis and surgical destruction of endometriosis. All patients were then treated with standard continuous medical therapy. Patients with exacerbation of pain on anti-endometriosis medical therapy who elected a subsequent laparoscopic procedure were eligible for this study.

INTERVENTION

Retrospective chart review

MAIN OUTCOME MEASURES

Endometriosis stage and adhesions at subsequent laparoscopy as compared to the initial surgical procedure.

RESULTS

90 patients met inclusion criteria. Eligible patients were 12 to 24 years of age at the time of the initial laparoscopy. The median endometriosis stage at first and second laparoscopy was I. No stage change was observed in 70% of patients, 19% improved by one stage, 1% improved by two stages, and 10% worsened by one stage. Regardless of initial stage, a trend toward disease progression was not observed. There was a significant likelihood for stage improvement at second laparoscopy, with those initially diagnosed as stage II or III most likely to exhibit improvement.

CONCLUSIONS

Based on the concept that endometriosis can be progressive, these data suggest that combined surgical-medical management retards disease progression in adolescents and young adults.

Vascular density and distribution of vascular endothelial growth factor (VEGF) and its receptor VEGFR-2 (Flk-1) are significantly higher in patients with deeply infiltrating endometriosis affecting the rectum

OBJECTIVE

To analyze vascular density and immunolocalization of angiogenic vascular endothelial growth factor (VEGF) and its receptor Flk-1 in the proliferative and secretory eutopic human endometrium and in three different sites of endometriosis: the ovary, bladder, and rectum.

DESIGN

Prospective study.

SETTING

University hospital.

PATIENT(S)

Thirty women with endometriosis (10 ovarian, 10 bladder, 10 rectal) and 32 control women (10 proliferative endometrium, 10 secretory endometrium, 4 normal ovary, 4 normal bladder, 4 normal rectum).

INTERVENTION(S)

Normal endometrial samples were obtained from women during laparoscopic ablation of subserous myoma, and biopsy specimens of endometriosis were obtained from patients undergoing surgery for the diagnosis and treatment of endometriosis. Normal tissues of ovary, bladder, and rectum were obtained from these organs beside the lesions of endometriosis.

MAIN OUTCOME MEASURE(S)

Blood vessels were quantified according to the number of von Willebrand factor-positive endothelial cells. The VEGF and Flk-1 distribution were evaluated semiquantitatively by immunohistochemical staining.

RESULT(S)

More blood vessels were found in cases of endometriosis, particularly rectal endometriosis, compared with the respective control samples and with the eutopic endometrium, and they were localized in endometrial stroma around the glands. The VEGF and Flk-1 expression levels were also higher in cases of endometriosis, especially rectal endometriosis.

CONCLUSION(S)

Vascularization and VEGF and Flk-1 expression are significantly higher in deeply infiltrating endometriosis affecting the rectum, reinforcing the hypothesis that antiangiogenesis therapy may constitute a new modality of treatment, especially in cases of deep endometriosis involving the rectum.

Why does menopausal hormone therapy lead to irregular uterine bleeding? Changes to endometrial blood vessels

BACKGROUND

Abnormal bleeding is common in hormone therapy (HT) users. We aimed to determine how HT alters endometrial blood vessels and stromal factors known to regulate vascular growth and integrity.

METHODS

Prospective observational study of 165 post-menopausal women in Western Australia. The following were measured in endometrial biopsies: vascular density (vessels/mm(2)), total vessel area (total area enclosed by peripheral vascular immunostaining for perivascular pericytes in mm(2)), total luminal area (mm(2)) and vessel wall area (total vessel area minus luminal area), stromal expression of matrix metalloproteinases (MMP) -1, -3, -9 and -14, their tissue inhibitors (TIMPs) -1-4 and vascular endothelial growth factor (VEGF) by immunohistochemistry.

RESULTS

Total vessel area was greater during bleeding compared with HT users with no bleeding (P = 0.028) or with a prior irregular bleeding (P = 0.039). Total vessel area was greater in non-HT users compared with HT users with no bleeding (P = 0.021). In HT users, vessel luminal area was greater during bleeding compared with HT users with no bleeding (P = 0.030) and vessel wall area was also increased (P = 0.025). During bleeding there was an increase in stromal TIMP-2 staining (P = 0.044). No significant changes in endometrial MMP or VEGF were seen.

CONCLUSIONS

Abnormal bleeding in HT users is associated with changes in endometrial vessel size and in stromal expression of factors known to regulate vascular growth and integrity. These changes may contribute to abnormal bleeding.

Image analysis measurements of the microvascularisation in endometrium, superficial and deep endometriotic tissues

The aim of this study was to evaluate precisely the microvascularisation of endometrium, superficial and deep endometriotic lesions, in progestin-treated and non-treated patients suffering from endometriosis.

METHODS

A population of 66 women was constituted. Immunohistochemistry was carried out with a specific marker of the endothelial cells (CD31). The number of vessels and the vessel area were assessed by a computer image analysis system.

RESULTS

The number of vessels per mm2 were 211, 216, 225 and the vessel area was 270, 141 and 194 microm2, respectively in endometria, superficial and deep endometriotic lesions of untreated women. In endometria, superficial and deep endometriotic lesions of progestin-treated women the number of vessels were respectively 129, 149, and 181 per mm2 and the vessel area was 369, 474 and 254 microm2.

CONCLUSION

Statistically significant data indicate that endometriotic lesions are heterogeneous and suggest that progestin treatment induces a reduction in number and a concomitant dilation of microvessels with more microvascular changes in endometrium and superficial endometriotic lesions than in deep endometriotic lesions.

Adenomyosis and reproduction

Evidence has been provided that pelvic endometriosis is significantly associated with uterine adenomyosis and that the latter constitutes the major factor of infertility in such conditions. Furthermore, it has become evident that both adenomyosis and endometriosis constitute a pathophysiological and nosological entity. Mild peritoneal endometriosis of the fertile woman and premenopausal adenomyosis of the parous and non-parous woman, as well as adenomyosis in association with endometriosis of the infertile woman, constitute a pathophysiological continuum that is characterized by the dislocation of basal endometrium. Due to the postponement of childbearing late into the period of reproduction, premenopausal adenomyosis might increasingly become a factor for infertility in addition to adenomyosis associated with endometriosis of younger women. In any event, the presence or absence of uterine adenomyosis should be examined in a sterility work-up.

Endometrial adenocarcinoma following insertion of the levonorgestrel-releasing intrauterine system (mirena) in a 36-year-old woman

The levonorgestrel-releasing intrauterine system (LNG-IUS), commonly referred to as mirena, is an effective form of contraception, which is widely used as an intrauterine device. It has a 32-mm long-shaped plastic frame that holds a reservoir (on the vertical stem) of 52 mg of levonorgestrel mixed with polydimethylsiloxane to allow a steady release of 20 mug of levonorgestrel per day within the endometrial cavity through a rate-limiting surface membrane. Apart from contraceptive purpose, it is also now commonly used in the management of heavy menstrual blood loss. This study included a 36-year old woman who developed endometrial cancer following the insertion of the LNG-IUS. Her main presentation was irregular vaginal bleeding, which is a common finding in women using this form of contraception. Although we would advice caution in investigating such women, the LNG-IUS remains a relatively safe method of contraception.

Human endometriotic xenografts in immunodeficient RAG-2/gamma(c)KO mice

OBJECTIVE

The purpose of this study was to create a novel animal model for studies of endometriosis.

STUDY DESIGN

To facilitate the study of the transplantation of endometriosis into immunodeficient RAG-2/gamma(c)KO mice, endometriosis biopsy specimens were collected from 19 women by laparoscopic surgery and grafted subcutaneously into the mice, which were treated subsequently with estradiol and progesterone to create 28-day artificial cycles. The grafts were collected during the first, second, and fourth cycles and were evaluated histologically for evidence of bleeding and immunocytochemically for estrogen receptor and progesterone receptor.

RESULTS

Biopsy specimens that contained endometrium-like glands were well accepted (>90% success). These grafts maintained glandular morphologic condition, estrogen receptor, and progesterone receptor; bled after progesterone withdrawal; and formed chocolate cysts. However, biopsy specimens that lacked glands or that consisted of peritoneal adhesions and stroma were accepted poorly <5% success) and failed to show evidence of estrogen receptor, progesterone receptor, or cyclic bleeding.

CONCLUSION

Human endometriosis transplanted into RAG-2/gamma(c)KO mice can provide a model for endometriotic bleeding.

Deep Endometriosis: Definition, Pathogenesis, and Clinical Management

"Deep endometriosis" includes rectovaginal lesions as well as infiltrative forms that involve vital structures such as bowel, ureters, and bladder. The available evidence suggests the same pathogenesis for deep infiltrating vesical and rectovaginal endometriosis (i.e., intraperitoneal seeding of regurgitated endometrial cells, which collect and implant in the most dependent portions of the peritoneal cavity and the anterior and posterior cul-de-sac, and trigger an inflammatory process leading to adhesion of contiguous organs with creation of false peritoneal bottoms). According to anatomic, surgical, and pathologic findings, deep endometriotic lesions seem to originate intraperitoneally rather than extraperitoneally. Also the lateral asymmetry in the occurrence of ureteral endometriosis is compatible with the menstrual reflux theory and with the anatomic differences of the left and right hemipelvis. Peritoneal, ovarian, and deep endometriosis may be diverse manifestations of a disease with a single origin (i.e., regurgitated endometrium). Based on different pathogenetic hypotheses, several schemes have been proposed to classify deep endometriosis, but further data are needed to demonstrate their validity and reliability. Drugs induce temporary quiescence of active deep lesions and may be useful in selected circumstances. Progestins should be considered as first-line medical treatment for temporary pain relief. However, in most cases of severely infiltrating disease, surgery is the final solution. Great importance must be given to complete and balanced counseling, as awareness of the real possibilities of different treatments will enhance the patient's collaboration.

Endometriose de septo retovaginal: doença de diagnóstico e tratamento específicos

RACIONAL: O envolvimento do septo retovaginal, reto e sigmóide pela endometriose pode causar sintomas intensos como dismenorréia, dor pélvica, dispareunia de profundidade, tenesmo e proctorragia cíclicos, em mulheres em idade reprodutiva. O diagnóstico pode ser suspeitado diante da história clínica típica e exame ginecológico adequado, ou ainda através de exame retal, enema opaco ou colonoscopia, entre outros. As indicações cirúrgicas, em geral, estão relacionadas à intensidade dos sintomas e falha no tratamento conservador. No entanto, o tratamento de escolha, para este tipo de endometriose, é a ressecção cirúrgica do tecido acometido, a fim de aliviar os sintomas e evitar progressão da doença. A localização correta assim como a avaliação da presença de extensão do processo em direção ao reto, ligamentos uterossacros ou septo retovaginal é extremamente importante para se garantir um tratamento cirúrgico eficaz. OBJETIVO: Descrever os principais aspectos relacionados à endometriose de septo retovaginal e fornecer aos cirurgiões gerais algumas informações específicas sobre esta enigmática doença. CONCLUSÃO: A endometriose de septo retovaginal é doença freqüente, de diagnóstico e tratamento específicos.

Noninvasive diagnosis of endometriosis: the role of imaging and markers

Endometriosis is defined by the presence of endometrial tissue outside the uterus. Clinical and basic research in endometriosis has been hampered severely by the lack of accurate noninvasive diagnostic techniques. Transvaginal ultrasonography, MRI, and endometrial and serum markers have the potential to facilitate the diagnosis and can be useful in the follow-up of patients. Endometriosis research has entered the postgenomic era, and powerful genomic and proteomic technology is being applied in the search for novel diagnostic and therapeutic approaches. This article explores the recent advances in imaging techniques and the development of diagnostic molecular markers of endometriosis.

Hormonally mediated disturbance of angiogenesis in the human endometrium after exposure to intrauterine levonorgestrel

BACKGROUND

The levonorgestrel intrauterine system (LNG-IUS) is a contraceptive device that is used for treatment of menorrhagia. The system induces inter-menstrual bleeding within the first few months after insertion. We hypothesized that this bleeding might be associated with a change in vascular development.

METHODS

A randomized, controlled study was undertaken on 48 women.

RESULTS

Hysterectomy specimens were obtained and immunocytochemistry was carried out with antibodies to CD31, alpha-smooth muscle actin and myosin. Stereological measurement of blood vessels was also undertaken. Most vessels appeared normal, including the arterioles. Large thin-walled vessels were present in the superficial endometrium of the treated group but were almost completely absent in the controls. The distribution of cytoskeletal markers revealed well-formed basal arterioles with more widespread expression in the superficial stroma than was found in untreated tissue. The volume fraction of blood vessels (P = 0.0001), the number of vessel cross-sections per unit area (P = 0.0003) and the cross-sectional diameters of the largest vascular lumens (P = 0.0001) were significantly increased following treatment with LNG-IUS. However, there was no difference in the median values of vessel diameter or the vascular surface density.

CONCLUSION

These findings suggest that the LNG has a localized effect on some vessels within the superficial endometrium.

Aromatase P450 messenger RNA expression in eutopic endometrium is not a specific marker for pelvic endometriosis

OBJECTIVE

To determine whether expression of aromatase P450 mRNA in eutopic endometrium is predictive of the presence of pelvic endometriosis.

DESIGN

A prospective, multicenter, observational study.

SETTING

Four tertiary centers for reproductive medicine.

PATIENT(S)

Sixty subjects of reproductive age undergoing laparoscopy for subfertility exploration, pain assessment, or sterilization.

INTERVENTION(S)

Endometrial biopsy at time of laparoscopy.

MAIN OUTCOME MEASURE(S)

The expression of aromatase P450 mRNA in endometrial specimens was determined by single-tube reverse transcription-polymerase chain reaction (RT-PCR). Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) mRNA was amplified in parallel to exclude amplification failure.

RESULT(S)

The RT-PCR amplification was successful in 56 of the 60 biopsies (93%). Pelvic endometriosis was diagnosed in 34 patients (61%) and was strongly associated with aromatase P450 mRNA expression in eutopic endometrium. As a diagnostic marker for endometriosis, aromatase P450 mRNA expression yielded a sensitivity of 82%, a specificity of 59%, a positive predictive value of 76%, and a negative predictive value of 67%. If additional uterine pathology was taken in account, the sensitivity increased to 84%, the specificity to 72%, the positive predictive value to 87%, but the negative predictive value remained unchanged (67%).

CONCLUSION(S)

Although endometrial aromatase P450 gene expression is highly predictive of the presence of pelvic disease, the relative high incidence of false-negative results and lack of specificity is likely to impair clinical application.

Functional association of PR and CCAAT/enhancer-binding protein beta isoforms: promoter-dependent cooperation between PR-B and liver-enriched inhibitory protein, or liver-enriched activatory protein and PR-A in human endometrial stromal cells

Activation of the decidual PRL (dPRL) promoter, a major differentiation marker in human endometrial stromal (ES) cells, by cAMP is effected through the induction and binding of CCAAT/enhancer-binding protein-beta (C/EBPbeta) to two overlapping cognate response elements in the promoter region dPRL-332/-270. Progesterone is essential for decidualization and potently enhances cAMP-dependent dPRL promoter activity. We now demonstrate that both liganded PR isoforms, PR-A and PR-B, are capable of trans-activating the dPRL-332/-270 region. The absence of a palindromic progesterone response element (PRE) within this promoter region suggested cross-coupling between C/EBPbeta and PR in human ES cells. Physical interaction between these distinct transcription factors was confirmed by glutathione-S-transferase pull-down assays, demonstrating that both C/EBPbeta isoforms, the full-length activator liver-enriched activatory protein (LAP) and the truncated inhibitor liver-enriched inhibitory protein (LIP), can bind PR-B as well as PR-A in vitro. Transient transfection studies in primary ES cells were used to examine the consequences of PR and C/EBPbeta interaction on activation of their respective response elements. Activation of mouse mammary tumor virus promoter or a reporter construct containing two isolated palindromic PREs by liganded PR-B was synergistically enhanced by coexpression of LIP, but not LAP. In contrast, PR-A failed to trans-activate these constructs significantly regardless of the presence of either C/EBPbeta isoform. Conversely, LAP-dependent activation of the dPRL-332/-270 region or a reporter construct driven by a single C/EBPbeta response element was greatly enhanced by PR-A, but not PR-B, in a ligand-dependent manner. These observations reveal that PR and C/EBPbeta isoform ratios are important determinants of the cellular response to ovarian progesterone in the reproductive tract; the predominance of PR-A and LAP favors expression of C/EBPbeta-dependent genes, whereas PR-B and LIP cooperate in activating PRE-driven promoters.