Concurrent estrogen action was essential for maximal progestin effect in oral contraceptives

Extensive heterogeneity in the expression of steroid receptors in superficial peritoneal endometriotic lesions

RESEARCH QUESTION

Is the expression of steroid hormone receptors (oestrogen receptor-α and progesterone receptor A/B) and proliferative markers (Bcl-2 and Ki67) uniform among superficial peritoneal endometriotic lesions?

DESIGN

A retrospective cohort study of 24 patients with surgically and histologically confirmed endometriosis. Immunofluorescence was used to determine the proportion of oestrogen receptor-α (ERα), progesterone receptor A/B, Bcl-2 and Ki67 positive cells in 271 endometriotic lesions (defined as endometriotic gland profile/s within an individual region of CD10 stromal immunostaining from a single biopsy) from 67 endometriotic biopsies from 24 patients. Data were analysed to examine associations related to menstrual cycle stage, lesion location and gland morphology.

RESULTS

Oestrogen receptor-α and progesterone receptor A/B expression in superficial peritoneal endometriotic lesions was extremely heterogeneous. Bcl-2 immunostaining in endometriotic lesions was also variable, whereas Ki67 immunostaining was minimal. Menstrual cycle stage associations were limited in steroid hormone receptor and Bcl-2 expression in lesions. Patterns in progesterone receptor A/B and Bcl-2 immunostaining were associated with lesion location. Bcl-2 was differentially expressed, based on lesion gland morphology.

CONCLUSIONS

These data demonstrate considerable diversity in the expression of steroid hormone receptors and Bcl-2 between lesions, even within an individual patient.

Effects of Ethinyl Estradiol in Combined Oral Contraceptives on Cell Proliferation and Apoptosis in Ectopic Endometrial Tissue: A Randomized Controlled Study

Objective: Since endometriosis is an estrogen-dependent disease; therefore, combined oral contraceptives (COCs) may not be the best choice for the treatment of endometriosis. The objective of the present study was to investigate the effects of ethinyl estradiol (EE) and desogestrel (DSG) in COCs on cell proliferation and apoptosis in ectopic endometrial tissue as compared to DSG alone. Materials and methods: Forty-five women of reproductive age with at least one endometriotic cyst were recruited into this single-blind randomized controlled trial study and randomly divided equally into three groups. EE-DSG and DSG groups received EE (0.03 mg) and DSG (0.15 mg) or DSG alone daily for 28-35 days before surgery. The control group was prescribed nothing. Endometriotic cyst tissues were collected during ovarian cystectomy for immunohistochemistry. Results: Levels of Ki-67 positive cells in the ectopic endometrial tissue of the EE-DSG group were significantly higher than the DSG group (median [IQR]; 1.4[1.2] vs 0.6 [0.7], P <0.016). There were significantly more TUNEL-positive cells in the EE-DSG group compared to the DSG group (median [IQR]; 2.8[0.7] vs 1.8[1.4], P < 0.016, respectively). Moreover, the number of TUNEL-positive cells in the EE-DSG and DSG groups were significantly higher than the control (median [IQR]; 2.8[0.7] vs 0.2[0.2] and 1.8[1.4] vs 0.2[0.2], P <0.016). The levels of cells that positively stained for Bcl2 were not different among all groups. Conclusion: Progestin alone increased cell apoptosis in ectopic endometria. However, concurrent EE in COCs enhanced proliferation and promoted a greater apoptotic effect in ectopic endometria compared to progestin alone.

Progesterone receptor ligands for the treatment of endometriosis: the mechanisms behind therapeutic success and failure

BACKGROUND

Despite intense research, it remains intriguing why hormonal therapies in general and progestins in particular sometimes fail in endometriosis.

OBJECTIVE AND RATIONALE

We review here the action mechanisms of progesterone receptor ligands in endometriosis, identify critical differences between the effects of progestins on normal endometrium and endometriosis and envisage pathways to escape drug resistance and improve the therapeutic response of endometriotic lesions to such treatments.

SEARCH METHODS

We performed a systematic Pubmed search covering articles published since 1958 about the use of progestins, estro-progestins and selective progesterone receptor modulators, to treat endometriosis and its related symptoms. Two reviewers screened the titles and abstracts to select articles for full-text assessment.

OUTCOMES

Progesterone receptor signalling leads to down-regulation of estrogen receptors and restrains local estradiol production through interference with aromatase and 17 beta-hydroxysteroid dehydrogenase type 1. Progestins inhibit cell proliferation, inflammation, neovascularisation and neurogenesis in endometriosis. However, progesterone receptor expression is reduced and disrupted in endometriotic lesions, with predominance of the less active isoform (PRA) over the full-length, active isoform (PRB), due to epigenetic abnormalities affecting the PGR gene transcription. Oxidative stress is another mechanism involved in progesterone resistance in endometriosis. Among the molecular targets of progesterone in the normal endometrium that resist progestin action in endometriotic cells are the nuclear transcription factor FOXO1, matrix metalloproteinases, the transmembrane gap junction protein connexin 43 and paracrine regulators of estradiol metabolism. Compared to other phenotypes, deep endometriosis appears to be more resistant to size regression upon medical treatments. Individual genetic characteristics can affect the bioavailability and pharmacodynamics of hormonal drugs used to treat endometriosis and, hence, explain part of the variability in the therapeutic response.

WIDER IMPLICATIONS

Medical treatment of endometriosis needs urgent innovation, which should start by deeper understanding of the disease core features and diverse phenotypes and idiosyncrasies, while moving from pure hormonal treatments to drug combinations or novel molecules capable of restoring the various homeostatic mechanisms disrupted by endometriotic lesions.

Continuous dosing of a novel contraceptive vaginal ring releasing Nestorone® and estradiol: pharmacokinetics from a dose-finding study

BACKGROUND

As part of a program to develop a novel estradiol-releasing contraceptive vaginal ring (CVR), we evaluated the pharmacokinetic (PK) profile of CVRs releasing segesterone acetate (Nestorone® (NES)) combined with one of three different estradiol (E2) doses.

STUDY DESIGN

A prospective, double-blind, randomized, multi-centered study to evaluate a 90-day CVR releasing NES [200mcg/day] plus E2, either 10mcg/day, 20mcg/day, or 40mcg/day in healthy reproductive-age women with regular cycles. Participants provided blood samples twice weekly for NES and E2 levels during the first 60 days (ring 1) and the last 30 days (ring 2) of use. A subset underwent formal PK assessments at ring initiation, ring exchange (limited PK), and study completion.

RESULTS

The main study enrolled 197 women; 22 participated in the PK substudy. Baseline characteristics between the main and PK participants were comparable, with an average BMI of 25.8 kg/m2 (SD 4.3). In the PK substudy, all three rings showed similar NES PK: mean area under the curve (AUC(0-72)) 34,181 pg*day/mL; concentration maximum (Cmax) 918 pg/mL; time to maximum concentration (Tmax) 3.5 h. For E2, the Cmax occurred at 2 h, and was significantly higher with the 20 mcg/day ring (mean 390 pg/mL); 10 mcg/day, 189 pg/mL, p=.003; 40 mcg/day, 189 pg/mL, p<.001), and declined rapidly to≤50 pg/mL for all doses by 24 h. For all subjects, the median E2 levels remained under 35 pg/mL during treatment.

CONCLUSION

PK parameters of NES were not affected when paired with different doses of E2, but E2 levels from all three doses were lower than anticipated and no dose response was observed.

IMPLICATIONS

While these novel estradiol-releasing combination contraceptive vaginal rings provided sustained release of contraceptive levels of Nestorone over 90 days, the E2 levels achieved were not consistent with bone protection, and a dose-response was not observed.

FDG-PET-positive ovarian thecoma with GLUT5 expression: Five cases

Positron emission tomography (PET) with fluorodeoxyglucose F18 (¹⁸ F-FDG) is useful for detecting malignancies, but benign lesions occasionally have false-positive ¹⁸ F-FDG uptake. Here, we report the cases of five postmenopausal women with solid ovarian tumors suspected to be ovarian cancer on magnetic resonance imaging and ¹⁸ F-FDG uptake. Mean age of the five patients was 57 years (range, 53-65 years). Average early standardized uptake value (SUV) of ¹⁸ F-FDG was 5.76 (range, 2.2-12.0) and delayed SUV was 6.56 (range, 2.4-13.8). In all five patients, frozen section diagnosis at surgery was thecoma, and bilateral salpingo-oophorectomy was performed. On immunohistochemistry, immunoreactive glucose transporter 5 (GLUT5) expression was detected in thecoma tissues. This case shows that thecoma sometimes has positive ¹⁸ F-FDG uptake on positron emission tomography-computed tomography (PET-CT), indicating the need for caution regarding false-positive PET-CT in patients with benign solid ovarian tumor.

Current strategies for endometriosis management

Endometriosis is a common gynecologic disorder that persists throughout the reproductive years. Although endometriosis is a surgical diagnosis, medical management with ovarian suppression remains the mainstay of long-term management with superimposed surgical intervention when needed. The goal of surgery should be excision or ablation of all visible disease to minimize risk of recurrence and need for repeat surgeries. When infertility is the presenting symptom, surgical therapy in addition to assisted reproductive technology can improve chances of conception; however, the treatment approach depends on stage of disease and other patient characteristics that affect fecundity.