Detection of aromatase cytochrome P-450 in endometrial biopsy specimens as a diagnostic test for endometriosis

Quality of reporting of test accuracy studies in reproductive medicine: impact of the Standards for Reporting of Diagnostic Accuracy (STARD) initiative

OBJECTIVE

To evaluate the extent to which test accuracy studies published in two leading reproductive medicine journals in the years 1999 and 2004 adhered to the Standards for Reporting of Diagnostic Accuracy (STARD) initiative parameters, and to explore whether the introduction of the STARD statement has led to an improved quality of reporting.

DESIGN

Structured literature search. Articles that reported on the diagnostic performance of a test in comparison with a reference standard were eligible for inclusion. For each article we scored how well the 25 items of the STARD checklist were reported. These items deal with the study question, study participants, study design, test methods, reference standard, statistical methods, reporting of results, and conclusions. We calculated the total number of reported STARD items per article, summary scores for each STARD item, and the average number of reported STARD items per publication year.

SETTING

Not applicable.

PATIENT(S)

Not applicable.

INTERVENTION(S)

Not applicable.

MAIN OUTCOME MEASURE(S)

Quality of reporting.

RESULT(S)

We found 24 studies reporting on test accuracy in reproductive medicine in 1999 and 27 studies in 2004. The mean number of reported STARD items for articles published in 1999 was 12.1 +/- 3.3 (range 6.5-20) and 12.4 +/- 3.2 (range 7-17.5) in 2004, after publication of the STARD statement. Overall, less than half of the studies reported adequately on 50% or more of the STARD items. The reporting of individual items showed a wide variation. There was no significant improvement in mean number of reported items for the articles published after the introduction of the STARD statement.

CONCLUSION(S)

Authors of test accuracy studies in the two leading fertility journals poorly report the design, conduct, methodology, and statistical analysis of their study. Strict adherence to the STARD guidelines should be encouraged.

Chronic pelvic pain and endometriosis in adolescents

PURPOSE OF REVIEW

This review will provide a detailed account of chronic pelvic pain and endometriosis, two conditions that frequently occur in adolescents. Current approaches used to evaluate and treat these patients will be addressed.

RECENT FINDINGS

Although previous investigations have established relative rates of disease and basic treatment algorithms for endometriosis in adolescents, its pathogenesis is yet to be explained. Recent scientific works have focused on the interplay of specific genes and the role of host immune response. Despite such progress, we have not yet learned how to apply this knowledge to clinical use. Most innovative treatment strategies are based on algorithms generated primarily for adults, with only a small percentage focusing on adolescents.

SUMMARY

Treating pain associated with endometriosis may be facilitated by early intervention. Future study should focus on identifying adolescents with progressive disease and introducing less invasive therapies that could reverse inflammatory pathways and minimize subsequent morbidity.

Expression of WT1 is down-regulated in eutopic endometrium obtained during the midsecretory phase from patients with endometriosis

OBJECTIVE

To investigate whether WT1 protein expression is altered in eutopic endometrium of endometriosis patients.

DESIGN

Prospective study.

SETTING

University hospital.

PATIENT(S)

Patients with endometriosis and fertile women with macroscopically normal pelvic cavities.

INTERVENTION(S)

During surgery, endometrial tissues were obtained from 59 patients with deep infiltrating endometriosis, ovarian endometriosis, or only superficial peritoneal endometriosis. Control endometrial tissue samples were obtained from 40 fertile women who underwent laparoscopic tubal ligation or reversal of tubal sterilization.

MAIN OUTCOME MEASURE(S)

The percentage of nuclear surface positively immunostained for WT1 (PI) and WT1-positive microvessel density.

RESULT(S)

The PI was significantly lower in endometrial stromal cells from patients with deep infiltrating endometriosis than in stroma from control subjects during the midsecretory phase, whereas there was no significant difference between the two populations during the proliferative, early secretory, and late secretory phases. The PI was also significantly lower during the midsecretory phase in endometrial stromal cells from patients with ovarian endometriosis and superficial peritoneal endometriosis compared with control subjects.

CONCLUSION(S)

During the midsecretory phase, PI in endometrial stromal cells is down-regulated in patients with deep infiltrating endometriosis, ovarian endometriosis, and superficial peritoneal endometriosis compared with endometrium from healthy control subjects.

Expression of aromatase, estrogen receptors, and their coactivators in patients with endometrial cancer

Quantitative polymerase chain reaction analysis of a panel of normal and malignant endometrial tissues revealed significant expression of both aromatase and estrogen receptor alpha in low-grade tumors, suggesting that local estrogen synthesis and action might contribute to the proliferation of these tumors.

Prolonged gonadotropin-releasing hormone agonist therapy reduced expression of nitric oxide synthase in the endometrium of women with endometriosis and infertility

OBJECTIVE

To determine whether endometrial expression of endothelial nitric oxide synthase (eNOS) or inducible NOS (iNOS) protein in women with endometriosis-associated infertility is different from that in the fertile controls, whether GnRH agonist (GnRH-a) regulates the endometrial expression of NOS in women with endometriosis-associated infertility, and whether there is a correlation between serum E2 or P levels, and the endometrial expression of eNOS or iNOS.

DESIGN

Prospective controlled study.

SETTING

University hospital for reproductive medicine and gynecologic endocrinology.

PATIENT(S)

Thirty patients with endometriosis-associated infertility and 19 patients with carcinoma in situ of the cervix.

INTERVENTION(S)

Endometrial biopsy specimens and blood samples.

MAIN OUTCOME MEASURE(S)

Endometrial eNOS and iNOS protein relative levels and serum concentrations of E2 or P.

RESULT(S)

By Western blot analysis, iNOS was not detected, and a unique menstrual cycle-dependent expression of eNOS was observed. Eutopic endometrium in women with endometriosis-associated infertility before GnRH-a treatment showed higher levels of eNOS than that of the control group. After 3 months of GnRH-a therapy, eNOS levels in the endometrium were reduced. In addition, a significant positive correlation was found between serum E2 or P concentrations, and the endometrial expression of eNOS.

CONCLUSION(S)

The GnRH-a treatment attenuated the endometrial expression of eNOS in women with endometriosis-associated infertility. Endogenous ovarian steroids influence endometrial eNOS expression.

Analysis of aromatase and 17beta-hydroxysteroid dehydrogenase type 2 messenger ribonucleic acid expression in deep endometriosis and eutopic endometrium using laser capture microdissection

OBJECTIVE

To investigate mRNA expression of aromatase and 17beta-hydroxysteroid dehydrogenase type 2 (17betaHSD2) in epithelial and stromal cells from eutopic and ectopic endometrium of patients with deep endometriosis.

DESIGN

Prospective study.

SETTING

University hospital.

PATIENT(S)

Patients with deep endometriosis and fertile women with macroscopically normal pelvic cavities.

INTERVENTION(S)

During surgery, 30 endometrial and 16 endometriotic samples were obtained from 30 patients with deep endometriosis. Control endometrial samples were obtained from 24 fertile women with macroscopically normal pelvic cavities who underwent laparoscopic tubal ligation or reversal of tubal sterilization. Epithelial cells and stromal cells from endometrial or endometriotic tissues were microdissected using laser capture microdissection.

MAIN OUTCOME MEASURE(S)

Expression levels of aromatase and 17betaHSD2 mRNA in microdissected epithelial and stromal cells were determined using quantitative real-time reverse transcriptase polymerase chain reaction.

RESULT(S)

Aromatase mRNA expression was significantly higher in epithelial cells than in stromal cells in both eutopic and ectopic endometrium obtained from endometriosis patients. In the ectopic endometrium of 8 patients (8/16, 50%), 17betaHSD2 expression was not detected in either epithelial or stromal cells. In eutopic endometrium from endometriosis patients, 17betaHSD2 expression in epithelial cells was significantly increased during the early, middle, and late secretory phases compared with the late proliferative phase, whereas no significant cyclical difference was detected in control endometrium.

CONCLUSION(S)

Local estrogen concentration may be much higher in epithelial cells than in stromal cells in deep endometriotic tissue.

Adenomyosis: the pathophysiology of an oestrogen-dependent disease

Adenomyosis uteri is a common gynaecological disorder that is characterized by the presence of ectopic endometrial glands and stroma in the myometrium. Although adenomyosis and endometriosis are different diseases, both of them grow and regress in an oestrogen-dependent fashion. Polymorphisms in the oestrogen receptor alpha gene are associated with a risk of adenomyosis. Adenomyotic tissue contains steroid receptors as well as aromatase and sulphatase enzymes. Together with the circulating oestrogen, locally produced oestrogens stimulate the growth of tissue mediated by the oestrogen receptors. Oestrogen metabolism, including the expression pattern of aromatase and the regulation of 17beta-hydroxysteroid dehydrogenase type 2 is altered in the eutopic endometrium of women with endometriosis, adenomyosis, and/or leiomyomas compared to that in the eutopic endometrium of women without disease. In addition to the conventional hormonal treatment with gonadotropin-releasing hormone agonists and danazol, the use of steroid-releasing intrauterine devices may be applicable to clinics.

[Adenomyosis: update on a frequent but difficult diagnosis]

Adenomyosis is a frequent entity, with difficult diagnosis, often obtained by pathological analysis performed after hysterectomy. This condition can cause abnormal uterine bleeding and dysmenorrhea, frequent reasons for consultation and hysterectomy. The development of ultrasonographic and magnetic resonance imaging techniques allow preoperative diagnosis. They also permit the use of hysteroscopic techniques for conservative uterine surgery, and have brought diagnosis and management of this disease to the front of the scene. This article reviews the pathological description of the disease, its epidemiology, clinical presentations, useful and necessary explorations, etiopathogeny and available therapies.

DNA microarray analysis of gene expression in eutopic endometrium from patients with deep endometriosis using laser capture microdissection

OBJECTIVE

To investigate differentially expressed genes in epithelial and stromal cells of eutopic endometrium from patients with deep endometriosis and women with normal pelvic cavities using laser capture microdissection and complementary DNA microarrays.

DESIGN

Prospective study.

SETTING

University hospital.

PATIENT(S)

Patients with deep endometriosis and fertile women who underwent laparoscopic tubal ligation or reversal of tubal sterilization.

INTERVENTION(S)

Endometrial tissue biopsies during the late proliferative phase and early, mid-, and late secretory phases.

MAIN OUTCOME MEASURE(S)

Genes that were regulated with a change greater than threefold were selected as differentially expressed genes. Validation was performed with real-time reverse transcriptase-polymerase chain reaction (RT-PCR).

RESULT(S)

Microarray analysis identified up-regulation during the late secretory phase (patients with endometriosis vs. controls) of several genes in two important signaling pathways: RAS/RAF/MAPK and PI3K. This included the genes RON, SOS, 14-3-3 protein eta, and uPAR in epithelial cells and KSR and PI3K p85 regulatory subunit alpha in stromal cells; real-time RT-PCR analysis validated up-regulation of all six genes.

CONCLUSION(S)

The RAS/RAF/MAPK and PI3K pathways may be involved in initial development of endometriosis.

Evaluation of clinical parameters and estrogen receptor alpha gene polymorphisms for patients with endometriosis

Endometriosis is a chronic inflammatory disease, which is especially found in women with subfertility problems with an incidence of up to 30%. The disease is considered an estrogen-dependent disorder, where DNA polymorphisms of the estrogen receptor α (ERα) in connection with endometriosis are controversially discussed. From a German population of women, clinical data associated with the disease, including the American Fertility Society (AFS) I–IV classification, and non-clinical parameters were evaluated statistically in endometriosis patients (n= 98) and in control women (n= 98) without endometriosis. Using a multivariate statistical analysis, significant associations of endometriosis with dysmenorrhea (P< 0.001) and allergies against medicaments (P= 0.042) were found. A positive trend between first grade family history of endometriosis and allergies against medicaments was also observed, suggesting a genetic relationship. From both collectives, DNA from peripheral blood was analyzed for the frequency of the ERα DNA polymorphisms Xba1 (A/G) and PvuII (T/C) in intron 1 and the ERα exonic DNA polymorphism (G229A) with an amino acid exchange (Gly77Ser) in the transactivation domain. DNA samples from endometriosis lesions and control tissues from the same collectives were also analyzed for the exonic G229A polymorphism. Only homozygote wild-type alleles for the polymorphism G229A were found, making it a rare polymorphism in mid-European individuals. Allele types for the PvuII and Xba1 polymorphisms were analyzed with the observed statistically significant clinical parameters and showed no significant association with endometriosis; however a trend with AFS IV was noted, which could contribute to lesion severity. In conclusion, the analyzed polymorphisms in the ERα do not have a functional role concerning specific clinical parameters associated with endometriosis.

Estrogen receptor-alpha (ER-alpha) and defects in uterine receptivity in women

Endometriosis is a disorder that affects 5% of the normal population but is present in up to 40% of women with pelvic pain and/or infertility. Recent evidence suggests that the endometrium of women with endometriosis exhibits progesterone insensitivity. One endometrial protein that fluctuates in response to progesterone is the estrogen receptor-alpha (ER alpha), being down-regulated at the time of peak progesterone secretion during the window of implantation. Here we demonstrate that the biomarker of uterine receptivity, beta 3 integrin subunit, is reduced or absent in some women with endometriosis and that such defects are accompanied by inappropriate over-expression of ER alpha during the mid-secretory phase. Using a well-differentiated endometrial cell line we showed that the beta 3 integrin protein is negatively regulated by estrogen and positively regulated by epidermal growth factor (EGF). By competing against estrogen with various selective estrogen receptor modulators (SERMs) and estrogen receptor agonists and antagonists, inhibition of expression of the beta 3 integrin by estrogen can be mitigated. In conclusion, we hypothesize that certain types of uterine receptivity defects may be caused by the loss of appropriate ER alpha down-regulation in the mid-secretory phase, leading to defects in uterine receptivity. Such changes might be effectively treated by timely administration of the appropriate anti-estrogens to artificially block ER alpha and restore normal patterns of gene expression. Such treatments will require further clinical studies.

Aromatase inhibitors and cyclooxygenase-2 (COX-2) inhibitors in endometriosis: New questions—old answers?

The medical treatment of endometriosis needs to be optimized. Therapeutic management strategies for endometriosis-associated pain or recurrent disease are primarily aimed at downregulating ovarian function or antagonizing the effect of estrogen in ectopic endometrial implants. In this context, basic research is providing important results for the development of new, specific treatment modalities. Aromatase overexpression has recently been detected in endometriotic tissue. Aromatase (p450arom) is responsible for converting C19 androgens into estrogen in several types of human tissue. Aromatase activity causes local estrogen biosynthesis, which, in turn, stimulates prostaglandin E2 production by upregulating cyclooxygenase-2 (COX-2). Thus, a positive feedback cycle develops between the two systems. Another abnormality in endometriosis, the deficient 17beta-hydroxysteroiddehydrogenase type II (17beta-HSD-Type-II) expression, impairs the inactivation of estradiol to estrone. In contrast to the eutopic endometrium, these molecular aberrations increase the amount of local estradiol and prostaglandin E2 in endometriosis. In several human cell lines, prostaglandin and estrogen concentrations are associated with proliferation, migration, angiogenesis, apoptosis resistance and even invasiveness. Consequently, aromatase and COX-2 are thought to be promising new therapeutic targets. Thus, specific aromatase inhibitors (e.g. Letrozol/Femara, Anastrozol/Arimidex or Exemestan/Aromasin) or selective COX-2 inhibitors (e.g. Celecoxib/Celebrex, Rofecoxib/Vioxx, Valdecoxib/Bextra) are of great interest and should be studied in clinical trials in premenopausal woman with endometriosis to expand the spectrum of currently available treatment options.

Role of the vaginally administered aromatase inhibitor anastrozole in women with rectovaginal endometriosis: a pilot study

In the present nonrandomized pilot study we determined the role of the vaginally administered aromatase inhibitor anastrozole (0.25 mg anastrozole/d for 6 months) in the treatment of women with histologically proven rectovaginal endometriosis. In a series of 10 patients, dysmenorrhea, physical and social functioning, but not chronic pelvic pain and dyspareunia, improved during therapy.

Anastrazole and oral contraceptives: a novel treatment for endometriosis

OBJECTIVE

To establish the use of aromatase inhibitors as a therapeutic option for endometriosis.

DESIGN

Prospective open-label Food and Drug Administration phase 2 trial with Institutional Review Board approval.

SETTING

Outpatient tertiary care centers.

PATIENT(S)

Fifteen premenopausal patients with documented refractory endometriosis and chronic pelvic pain.

INTERVENTION(S)

After a 1-month washout of endometriosis hormone therapies, women took 1 mg anastrazole (Arimidex; AstraZeneca, Wilmington, DE) and one tablet of 20 microg ethinyl estradiol/0.1 mg levonorgestrel (Alesse; Wyeth, Madison, NJ) daily for 6 months.

MAIN OUTCOME MEASURE(S)

An analog pain scale recorded pelvic pain in daily diaries and surveys at baseline and after each treatment month. Side effects, blood counts, liver and renal function tests, cholesterol levels, and bone density were monitored.

RESULT(S)

Fourteen of 15 patients achieved significant pain reduction. Median pain scores decreased 55% after 6 months, while mean pain scores decreased 40%. Pain reduction comparing each treatment month to baseline achieved statistical significance. Average pain scores began dropping after only 1 treatment month and continued decreasing each additional month. No organ system experienced adverse effects. Estradiol levels were suppressed during treatment. Side effects were mild and improved over time.

CONCLUSION(S)

Fourteen of 15 patients with refractory endometriosis achieved significant pain relief using anastrazole and 20 microg ethinyl estradiol/0.1 mg levonorgestrel with minimal side effects. This treatment for endometriosis is a promising new modality that warrants further investigation.

DDE-induced changes in aromatase activity in endometrial stromal cells in culture

Environmental toxicants are thought to play a role in several estrogen-dependent diseases including breast cancer and endometriosis. Toxicant-induced increased aromatase activity, an enzyme complex that catalyzes the final rate-limiting step in the conversion of androgens to estrogens, has been reported in assays using placental microsomes and cancer cells in vitro. These data suggest that environmental toxicants can increase aromatase activity and thus increase local tissue estrogen levels, which could have implications for estrogen- dependent functions in target tissues. The objective of this study was therefore to quantify the effect of the stable breakdown product of DDT, 2,2-bis(p-chlorophenyl)ethylene (p,p'-DDE), a toxicant broadly detected in human adipose tissue, serum and follicular fluid, on aromatase activity in the endometrium, an estrogen-sensitive target tissue. Specifically, the effect of increasing log concentrations of p,p'-DDE on aromatase activity was determined in cultures of endometrial stromal cells (ESC). Relative to controls p,p'-DDE treatment significantly increased aromatase activity in ESC (135%). Moreover, ESC cells treated with p,p'-DDE were immunopositive for aromatase, whereas no aromatase staining could be demonstrated in control cultures. Our data demonstrate that p,p'-DDE treatment can increase aromatase activity in ESC in culture.

Usefulness and limits of CA-125 in diagnosis of endometriosis without associated ovarian endometriomas

BACKGROUND

The aim of this study was to evaluate the diagnostic significance of CA-125 for endometriosis without ovarian endometriomas.

METHODS

Preoperative serum CA-125 levels were measured in 775 consecutive women diagnosed by laparoscopy or laparotomy with endometriosis, adenomyosis, leiomyomas, or normal pelvis.

RESULTS

Receiver operating characteristic curve analysis revealed that the area under the curve for endometriosis without endometriomas was 0.788, significantly smaller than that for endometriosis with endometriomas (0.935, P < 0.05). In diagnosis of endometriosis without endometriomas, both the maximal accuracy of 78.8% and the maximal diagnostic value of 61.2% were obtained at the cutoff value of 20 U/mL. Negative predictive value was 78.0% at the cutoff value of 20 U/mL, whereas positive predictive value was 92.9% at the cutoff value of 30 U/mL. This range is clearly superior to the empirical single cutoff of 35 U/mL.

CONCLUSIONS

In the diagnosis of endometriosis without endometriomas, combined use of two cutoff values for CA-125, 20 and 30 U/mL, provides improved diagnostic performance. However, the accuracy of using only CA-125 testing for diagnosis is still limited. Serum CA-125 testing can be done during initial screenings of women with possible endometriosis.

A predictive model for endometriosis

BACKGROUND

Aromatase is the key enzyme in the process of estrogen biosynthesis from the precursor androgen. Recently, aromatase has been found to be aberrantly expressed in eutopic endometrium of patients suffering from endometriosis. This finding has prompted speculation about the contribution of this enzyme to the prediction of this disease.

METHODS

We prospectively aimed to evaluate whether endometrial biopsy, prior to laparoscopy in symptomatic women to screen for the presence of aromatase by real-time RT-PCR and immunohistochemistry, combined with select patients' characteristics, is of value to predict endometriosis.

RESULTS

Of 48 consecutive symptomatic and eligible patients, 25 (52.1%) exhibited endometriosis and 23 (47.9%) were disease-free. A multiple logistic regression model revealed that 95.5% of patients whose eutopic endometrium was found to be positive for aromatase mRNA as well as immunohistochemically detected protein and who were additionally suffering from moderate to severe dysmenorrhoea (visual analogue scale score >4/10) exhibited endometriosis at laparoscopy.

CONCLUSIONS

These findings provide direct evidence that screening for eutopic endometrial aromatase in combination with clinical data could be of discriminative value in the prediction of disease.

Non-invasive methods of diagnosis of endometriosis

PURPOSE OF REVIEW

Laparoscopy is the gold standard for the diagnosis of endometriosis but the need for visual evidence of the disease is a major stumbling-block for both effective clinical management of affected patients as well as for research into this common and debilitating reproductive disease. Laparoscopy is invasive and often causes a delay in diagnosis and treatment, especially in symptomatic teenagers and young women. Moreover, the visual inspection of the pelvis has major limitations, particularly for the diagnosis of retroperitoneal lesions. It is therefore not surprising that considerable efforts are being made to improve imaging techniques and to evaluate the diagnostic value of potential molecular markers of disease.

RECENT FINDINGS

High-resolution transvaginal ultrasonography and, in selected cases, magnetic resonance imaging improve the diagnosis of retroperitoneal pelvic endometriosis as well as the identification of lesions that involve pelvic organs. A variety of serum and endometrial markers are being evaluated for their diagnostic potential, particularly in endometriosis associated infertility. The first gene profiling studies are showing positive results and proteomic technology is being applied to identify novel diagnostic protein expression patterns.

SUMMARY

Current imaging techniques, such as transvaginal ultrasonography, are useful to screen the pelvis for the presence of retroperitoneal endometriosis but fail to diagnose peritoneal lesions, small ovarian endometriomas and adhesions. Postgenomic technologies and identification of novel serum and endometrial markers are likely to revolutionize future diagnosis of endometriosis.

Aromatase cytochrome P450 and estrogen and progesterone receptors in uterine sarcomas: correlation with clinical parameters

We examined the immunohistochemical expression of aromatase cytochrome P450 (P450arom), estrogen receptor (ER), progesterone receptor (PR), and Ki-67 in postoperative uterine sarcomas (n = 31) and the corresponding eutopic endometria (n = 20) to evaluate the relationships between the endocrine character of uterine sarcomas and the clinical features. In sarcoma tissues, P450arom was detected in 55% of cases, ER in 42%, PR in 42%, and Ki-67 in 90%. In eutopic endometria, P450arom was detected in 60% of cases, ER in 60%, and PR in 35%. There were correlations in the steroid-related proteins between the tumors and endometria (P = 0.001-0.026). The positivity of endometrial P450arom (P = 0.04) and ER (P = 0.006) was higher in surviving patients than dead patients regardless of the menstrual state. The results demonstrate correlation between the expression of P450arom, ER, and PR in tumors and eutopic endometria. Intense expression of the steroid-related proteins was associated with better survival.

Steroid receptor and aromatase expression in baboon endometriotic lesions

OBJECTIVE

To evaluate steroid receptor and aromatase gene expression in endometriotic lesions, and determine the effects of endometriosis on uterine receptivity in a baboon model for endometriosis.

DESIGN

Prospective study to determine the expression of steroid receptors, and aromatase in ectopic endometriotic lesions and endometrial genes in the eutopic endometrium of baboons with induced endometriosis by reverse transcriptase-polymerase chain reaction (RT-PCR) and immunocytochemistry.

SETTING

University research laboratory and primate research facility.

ANIMAL(S)

Normally cycling baboons inoculated intraperitoneally with menstrual endometrium to induce endometriosis.

INTERVENTION(S)

Endometriotic lesions were resected during laparotomy, and endometrium was obtained by endometrectomy or after hysterectomy.

MAIN OUTCOME MEASURE(S)

Steroid receptor and aromatase expression by RT-PCR and immunocytochemistry in endometriotic lesions and glycodelin and alpha-smooth muscle actin expression and localization in endometrium after chorionic gonadotropin (CG) stimulation.

RESULT(S)

This study demonstrated that estrogen receptor-alpha (ERalpha) and progesterone receptor (PR) were expressed in both ectopic and eutopic endometrium between 1 and 10 months after inoculation. In contrast, ERbeta was only expressed in the ectopic endometriotic lesions. Aromatase expression was only evident in lesions obtained 10 months after inoculation. Infusion of CG during the luteal phase failed to induce the expression of glycodelin in the glandular epithelium or alpha-smooth muscle actin (alpha-SMA) in stromal cells in animals with endometriosis as early as 1 and 4 months after inoculation.

CONCLUSION(S)

The ERbeta expression is selectively up-regulated in the endometriotic lesions at all stages of the disease, whereas aromatase expression is not evident until the disease progresses. However, expression of uterine receptivity markers was down-regulated as early as 1 and 4 months after inoculation.

Development of a nonsurgical diagnostic tool for endometriosis based on the detection of endometrial leukocyte subsets and serum CA-125 levels

OBJECTIVE

To determine whether the proportion of several leukocyte subsets is modulated in the endometrium of patients with endometriosis and, if yes, whether it can be used for diagnostic purposes.

DESIGN

Case-control study.

SETTING

Eight clinical institutions of the Montreal area.

PATIENT(S)

Women who underwent laparoscopy or laparotomy between 1997 and 2001, who had regular menstrual cycles and were not under hormone treatment for the previous 3 months were selected. This study included 368 women, 173 with surgically confirmed endometriosis and 195 controls with no surgical evidence of endometriosis.

INTERVENTIONS

MAIN OUTCOME MEASURE(S)

Cytometry analysis was used to measure the proportion of several leukocyte subsets among CD45(+) endometrial cells.

RESULT(S)

The proportion of CD3(+), CD16(+), CD3(-)HLADR(-), CD3(-)CD45RA(-), CD3(+)CD16(-), CD3(+)CD56(-), CD56(-)CD16(+), and CD16b(+) leukocytes was significantly altered in the endometrium of cases compared with controls. A multiple logistic regression model was adjusted with these endometrial leukocytes, serum CA-125 levels, risk factors, and confounders. The diagnostic performance of this predictive model was defined by a specificity of 95% and a sensitivity of 61%. Furthermore, the positive and negative predictive values were 91% and 75%, respectively.

CONCLUSION(S)

This predictive model represents a novel diagnostic tool to identify women with a high likelihood of suffering from endometriosis.

Expression profiling of endometrium from women with endometriosis reveals candidate genes for disease-based implantation failure and infertility

Endometriosis is clinically associated with pelvic pain and infertility, with implantation failure strongly suggested as an underlying cause for the observed infertility. Eutopic endometrium of women with endometriosis provides a unique experimental paradigm for investigation into molecular mechanisms of reproductive dysfunction and an opportunity to identify specific markers for this disease. We applied paralleled gene expression profiling using high-density oligonucleotide microarrays to investigate differentially regulated genes in endometrium from women with vs. without endometriosis. Fifteen endometrial biopsy samples (obtained during the window of implantation from eight subjects with and seven subjects without endometriosis) were processed for expression profiling on Affymetrix Hu95A microarrays. Data analysis was conducted with GeneChip Analysis Suite, version 4.01, and GeneSpring version 4.0.4. Nonparametric testing was applied, using a P value of 0.05, to assess statistical significance. Of the 12,686 genes analyzed, 91 genes were significantly increased more than 2-fold in their expression, and 115 genes were decreased more than 2-fold. Unsupervised clustering demonstrated down-regulation of several known cell adhesion molecules, endometrial epithelial secreted proteins, and proteins not previously known to be involved in the pathogenesis of endometriosis, as well as up-regulated genes. Selected dysregulated genes were randomly chosen and validated with RT-PCR and/or Northern/dot-blot analyses, and confirmed up-regulation of collagen alpha2 type I, 2.6-fold; bile salt export pump, 2.0-fold; and down-regulation of N-acetylglucosamine-6-O-sulfotransferase (important in synthesis of L-selectin ligands), 1.7-fold; glycodelin, 51.5-fold; integrin alpha2, 1.8-fold; and B61 (Ephrin A1), 4.5-fold. Two-way overlapping layer analysis used to compare endometrial genes in the window of implantation from women with and without endometriosis further identified three unique groups of target genes, which differ with respect to the implantation window and the presence of disease. Group 1 target genes are up-regulated during the normal window of implantation but significantly decreased in women with endometriosis: IL-15, proline-rich protein, B61, Dickkopf-1, glycodelin, N-acetylglucosamine-6-O-sulfotransferase, G0S2 protein, and purine nucleoside phosphorylase. Group 2 genes are normally down-regulated during the window of implantation but are significantly increased with endometriosis: semaphorin E, neuronal olfactomedin-related endoplasmic reticulum localized protein mRNA and Sam68-like phosphotyrosine protein alpha. Group 3 consists of a single gene, neuronal pentraxin II, normally down-regulated during the window of implantation and further decreased in endometrium from women with endometriosis. The data support dysregulation of select genes leading to an inhospitable environment for implantation, including genes involved in embryonic attachment, embryo toxicity, immune dysfunction, and apoptotic responses, as well as genes likely contributing to the pathogenesis of endometriosis, including aromatase, progesterone receptor, angiogenic factors, and others. Identification and validation of selected genes and their functions will contribute to uncovering previously unknown mechanism(s) underlying implantation failure in women with endometriosis and infertility, mechanisms underlying the pathogenesis of endometriosis and providing potential new targets for diagnostic screening and intervention.

CYP1A1, CYP19, and GSTM1 polymorphisms increase the risk of endometriosis

OBJECTIVE

To investigate the possibility of genetic contribution of CYP1A1, CYP19, GSTM1, and GSTT1 polymorphisms to endometriosis.

DESIGN

Genetic polymorphism analysis.

SETTING

Case-control study.

PATIENT(S)

A group of 275 women with sporadic endometriosis was compared with a group of 346 fertile, endometriosis-free women.

INTERVENTION(S)

Surgical, laparoscopic, and histological examination.

MAIN OUTCOME MEASURE(S)

Blood specimens were obtained from endometriosis cases and controls. Polymerase chain reaction-based assays were performed for the determination of individual's genotype.

RESULT(S)

The CYP19 VNTR, located in intron 4 (TTTA)(10) allele increases the risk for endometriosis development (odds ratio [OR], 4.99; 95% confidence interval [95% CI], 1.351 to 18.436). The combined genotype CYP1A1 wt/m1 or m1/m1 and GSTM1 null deletion adds to this risk (OR, 1.95; 95% CI, 1.266 to 2.995 and OR, 2.23; 95% CI, 0.631 to 7.906, respectively). In contrast, the CYP1A1 wt/wt genotype exhibits a protective effect, with a 38% reduction in the odds for endometriosis development (OR, 0.62; 95% CI, 0.440 to 0.883).

CONCLUSION(S)

Our data suggest that CYP19 VNTR (TTTA)(10) allele as well as the combined genotype CYP1A1 m1 polymorphism and GSTM1 null deletion associate with the endometriosis phenotype, whereas the GSTT1 null deletion does not.

Gonadotropin-releasing hormone agonist and danazol normalize aromatase cytochrome P450 expression in eutopic endometrium from women with endometriosis, adenomyosis, or leiomyomas

OBJECTIVE

To investigate whether GnRH agonists or danazol therapy normalizes estrogen metabolism in the eutopic endometrium of women with endometriosis, adenomyosis, or leiomyomas.

DESIGN

Prospective clinical study.

SETTING

University hospital.

PATIENT(S)

Fifty-three women with endometriosis, adenomyosis, or leiomyomas.

INTERVENTION(S)

Patients received GnRH agonist or danazol. Biopsy samples of the endometrium were obtained before and after endocrine therapy. Nontreated endometrial explants were cultured in the presence of either drug.

MAIN OUTCOME MEASURE(S)

Reverse transcription polymerase chain reaction-Southern blot and immunohistochemical analyses of the endometrial expression of aromatase cytochrome P450, estrogen receptor, progesterone receptor, and Ki-67. Nontreated endometrial explants were cultured in the presence of either drug.

RESULT(S)

Messenger RNA and protein of aromatase cytochrome P450 were greatly reduced in the eutopic endometrium of patients treated with GnRH agonist for 2 months or more or with danazol for 1 month or more. Culture of endometrial explants with GnRH agonist (10(-9)-10(-7) M) did not change the amount of aromatase cytochrome P450, whereas danazol (10(-7)-10(-6) M) efficiently reduced aromatase cytochrome P450 expression.

CONCLUSION(S)

Therapy with GnRH agonist or danazol decreases expression of aromatase cytochrome P450 in diseased eutopic endometrium. Endocrine therapy normalized in part the impaired hormonal expression of the eutopic endometrium. GnRH agonist reduced aromatase cytochrome P450 expression mainly by promoting a hypoestrogenic state, whereas danazol reduced aromatase cytochrome P450 in part by direct action on the eutopic endometrium.

Stromal vascularization in the endometrium during adenomyosis

In adenomyosis, the two major frequent symptoms are hypermenorrhea and dysmenorrhea. The incidence of the former is said to be high, ranging from 36 to 70%. It has been found that vascular distribution of the endometrium in adenomyosis is diversely different from fertile patients without adenomyosis. For example, hysteroscopy revealed that approximately half of the patients have abnormal vascularization. In these patients, vascular distribution was generally irregular, and vessels were thick, dilated, and/or reticular in some patients. Moreover, morphometric analysis of the endometrium revealed that in the fertile women, the mean surface area, total surface area, and total number of capillaries, all increased significantly in the secretory phase compared to the proliferative phase. In contrast, the above parameters increased in the adenomyosis group in both the proliferative phase and secretory phase compared to the fertile women. In particular, the total surface area of capillaries per mm(2) markedly rose, by 11.6 times, compared to that of the proliferative phase in the fertile women. These findings suggest that regulatory factors involved in the vascular proliferation are diversely exaggerated, and that the abnormal vascularization of the endometrium is closely related with hypermenorrhea.

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.

Reproductive disorders affecting fertility in endometriosis

The classical concept of endometriosis as a cause of infertility is challenged. Traditionally, both surgical and medical therapy of endometriosis-associated infertility has focused on eliminating or reducing the visible implants. The classic 6-month medical approach has been a failure, and surgery may moderately enhance fertility, but its benefit in the absence of adhesions is still doubtful. Recent studies have shown that endometriosis is characterized by an aberrant response to sex steroid hormones, resulting in pleiotropic dysfunctions of the reproductive system involving the uterine, peritoneal and ovarian micro-environment. Studies on endometriosis and IVF have been highly relevant in revealing the pleiotropic dysfunctions in patients with endometriosis, although the results should be interpreted with caution. The conclusion seems to support the view that infertility in patients with endometriosis is primarily dysfunctional, rather than lesional, in origin. It is concluded that the place of medical therapy in endometriosis should be reviewed and that the surgical approach needs to be complemented by appropriate medical therapy to restore fertility.

Endometriosis: the pathophysiology as an estrogen-dependent disease

Endometriosis, defined as the presence of endometrial glands and stroma outside of the uterine cavity, develops mostly in women of reproductive age and regresses after menopause or ovariectomy, suggesting that the growth is estrogen-dependent. Indeed, the lesions contain estrogen receptors (ER) as well as aromatase, an enzyme that catalyses the conversion of androgens to estrogens, suggesting that local estrogen production may stimulate the growth of lesions. The expression patterns of ER and progesterone receptors in endometriotic lesions are different from those in the eutopic endometrium. Moreover, estrogen metabolism, including the expression pattern of aromatase and the regulation of 17 beta-hydroxysteroid dehydrogenase type 2 (an enzyme responsible for the inactivation of estradiol to estrone), is altered in the eutopic endometrium of women with endometriosis, adenomyosis, and/or leiomyomas compared to that in the eutopic endometrium of women without disease. Immunostaining for P450arom in endometrial biopsy specimens diagnosed these diseases with sensitivity and specificity of 91 and 100%, respectively. This is applicable to the clinical diagnosis of endometriosis. The polymorphisms in the ER-alpha gene, the CYP19 gene encoding aromatase, and several other genes are associated with the risk of endometriosis. Studies of these will lead to better understandings of the etiology and pathophysiology of endometriosis.

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.

Oestrogen receptor-alpha gene polymorphism is associated with endometriosis, adenomyosis and leiomyomata

Endometriosis, adenomyosis and leiomyomata develop in women of reproductive age and regress after menopause or ovariectomy, suggesting that they grow in an oestrogen-dependent fashion. We investigated whether polymorphism in the oestrogen receptor-alpha (ERalpha) gene is related to oestrogen-dependent benign uterine disease. A total of 203 women with regular menstrual cycles underwent laparotomy or laparoscopy and were diagnosed histologically with endometriosis, adenomyosis and/or leiomyomata. Patients with cervical carcinoma in situ, tubal occlusion or adhesion but no other gynaecological disease were considered to be disease-free. A total of 179 women undergoing annual health examination were grouped as reference population. The distribution of PVUII genotypes (PP, Pp, and pp) of the ERalpha gene was different between each pair of the four groups of endometriosis, adenomyosis/leiomyomata, disease-free, and reference population (P = 0.022-0.0005), except between the former two groups. The PP genotype was less frequent in the groups of endometriosis (P = 0.0002) and adenomyosis/leiomyomata (P = 0.002) as compared to that in the disease-free group. In the endometriosis group, there was no difference in the distribution of PVUII genotypes due to complicating diseases (adenomyosis and/or leiomyomata) or severity of the clinical stages. These results suggest that the PVUII polymorphism of the ERalpha gene is associated with the risk for endometriosis, adenomyosis, and leiomyomata.

Expression of leptin receptor in human endometrium and fluctuation during the menstrual cycle

Leptin is secreted by adipocytes and regulates appetite through interaction with hypothalamic leptin receptors (OB-R). Accumulated evidence shows that leptin is involved in the stimulation of reproductive functions and that local expression of leptin and OB-R in the ovary, oocyte, embryo, and placenta plays a role in early development. To investigate the role of leptin in implantation, we examined the expression of OB-R and leptin in the human endometrium. Northern and Western blot analyses and RT-PCR showed that the long form of OB-R (OB-R(L)) messenger ribonucleic acid (mRNA) and protein were expressed. In contrast, leptin mRNA or protein was not detected. All of the splice variants of OB-R (OB-R(T)) and OB-R(L) transcripts were expressed in 90% and 84% of the cases, respectively. OB-R mRNA expression peaked in the early secretory phase. Decidual tissue of early gestation also expressed OB-R(T) and OB-R(L). Their incidence and abundance were comparable among endometria with benign uterine diseases and disease-free endometria and were not related to a body mass index within the normal range. The present results indicate that OB-R, but not leptin, is expressed in the human endometrium.