Metformin for endometrial hyperplasia

The Association Between Metabolic Syndrome and the Risk of Endometrial Cancer in Pre- and Post-Menopausal Women: A UK Biobank Study

Background: Metabolic syndrome (MetS) is a syndrome that comprises central obesity, increased serum triglyceride (TG) levels, decreased serum HDL cholesterol (HDL) levels, raised blood pressure (BP), and impaired glucose regulation, including prediabetic and diabetic glycaemic levels. Recently, the association with endometrial cancer (EC) has been described but it is unclear if the risk associated with MetS is higher than the individual effect of obesity alone. This study investigates the association between MetS components and differing MetS definitions on EC risk and compares the risk of MetS with the risk posed by obesity alone. It also analyses how MetS affects the risk of EC development in the pre- and post-menopausal subgroups. Methods: A prospective cohort study was undertaken using data from the UK biobank. Multivariable Cox proportional risk models with the time to diagnosis (years) were used to estimate the hazard ratio (HR) and 95% confidence interval (CI) of MetS and its components on the risk of EC. A subgroup analysis was also undertaken for pre- and post-menopausal participants. Kaplan-Meier (KM) was undertaken to assess the difference in the risk of EC development in differing BMI classes, and in pre- and post-menopausal subgroups. Results: A total of 177,005 females from the UK biobank were included in this study. Of those participants who developed EC (n = 1454), waist circumference > 80 cm, BMI > 30 kg/m2, hypertension > 130/80 mmHg, hyperlipidaemia and diabetes (HbA1C > 48 mmol/L were significant predictors of EC development, with waist circumference being the strongest predictor (HR = 2.21; 95% CI: 1.98-2.47, p < 0.001). Comparing the pre- and post-menopausal subgroup, hypertriglyceridaemia and diabetes were the strongest predictors of EC in the pre-menopausal subgroup (HR = 1.53; 95% CI: 1.18-1.99 and HR = 1.51; 95% CI: 1.08-2.12, p < 0.05, respectively). Raised waist circumference was not a significant independent predictor in the pre-menopausal subgroup. A KM curve analysis showed a clear distinction between those with and without MetS in the pre-menopausal group, suggesting a benefit of testing for MetS components in pre-menopausal women with obesity. Conclusions: Components of MetS, both independently and in combination, significantly increase the risk of EC. Screening those with obesity for MetS in their pre-menopausal years may help to identify those at the highest risk.

Efficacy of drugs treatment in patients with endometrial hyperplasia with or without atypia: A systematic review and network meta-analysis

BACKGROUND

Endometrial hyperplasia (EH) is a hyperplastic endometrial lesion with irregular gland size, increased glands, and increased glandular interstitial ratio. During follow-up, some EH progressed further to endometrial cancer. It is crucial to provide timely treatment for EH and improve the overall prognosis of EH patients.

METHODS

We searched the PubMed, ClinicalTrials.gov., and Embase databases for studies published from their inception to March 31, 2023. The methodological quality of each study was evaluated in accordance with the Cochrane Collaboration's tool for assessing the risk of bias. The RevMan5.3 software provided by the Cochrane Collaboration was used for direct meta-analysis statistical analysis; and the relative risk and 95% confidence interval along with the mean difference and 95% confidence interval, were used as evaluation indexes.

RESULTS

We included 21 randomized controlled trials involving a total of 2276 women with EH, 6 studies were of high quality, and 15 were of moderate quality. The blinding of subjects and intervention providers was identified as the main source of potential bias. Six interventions were addressed in the network meta-analysis: medroxyprogesterone acetate (MPA), plus metformin, norethisterone (NET), levonorgestrel-releasing intrauterine system (LNG-IUD), megestrol acetate, and other drugs. In the direct meta-analysis, we found the probability of endometrial complete regression (CR) in the LNG-IUD group to be significantly higher than those in the NET. In the network meta-analysis, we found the probability of CR in the NET group to be significantly lower than those in the MPA and plus metformin groups, the probability of CR in the LNG-IUD group to be significantly higher than those in the NET, the probability of CR in the other drugs group to be significantly higher than those in the LNG-IUD. The NET group had the lowest incidences of endometrial complete regression, plus metformin could have a better outcome.

CONCLUSION

According to the 21 randomized controlled trials included in this study, MPA is the most effective for EH endometrial outcome when applied as a single agent, while the combination of metformin can achieve a more significant effect.

A multi-centre randomised controlled trial comparing megestrol acetate to levonorgestrel-intrauterine system in fertility sparing treatment of atypical endometrial hyperplasia

PURPOSE

The objective of the trial was to compare the regression rate of atypical endometrial hyperplasia (AEH) in patients treated with megestrol acetate (MA) vs. levonorgestrel-intrauterine device (LNG-IUS). We also aimed to assess the fertility and pregnancy outcomes in these patients.

METHODS

The study was a phase II multi-centre randomised controlled trial on the use of MA compared to LNG-IUS in the treatment of AEH conducted from January 2020 to January 2024 in Singapore. Women who were diagnosed with AEH and between 21 and 40 years old were included. The patients were randomised to receive either MA (160 mg orally daily) or LNG-IUS. The primary outcomes assessed were the regression rates at 3 months, 6 months and 9 months of treatment. The secondary outcomes assessed were the side effects, patient acceptability and fertility outcomes.

RESULTS

Thirty-six patients completed the trial. The overall regression rate was 88.9% by 9 months. There was no statistically significant difference in the 9-month complete regression rate between MA vs. LNG-IUS. There was also no significant difference in side effects and weight change between both arms. Nineteen patients were actively pursuing fertility after complete regression. There were 8 pregnancies achieved, with resultant 4 live births and 4 miscarriages.

CONCLUSION

Our study confirms a high regression rate of AH with medical treatment. LNG-IUS is a non-inferior treatment compared to megestrol acetate. Successful pregnancy outcomes can be achieved after regression of AEH. Long-term studies of sufficient sample-size are needed to assess for fertility and pregnancy outcomes, risk of recurrence and long-term risk of malignancy.

TRIAL REGISTRATION NUMBER

The study was registered with the Health Science Authority (HSA) (License No.: CTA1900087) on September 5, 2019: https://eservice.hsa.gov.sg/prism/ct_r/enquiry.do?action=loadSpecificDetail . The trial was registered retrospectively on ClinicalTrials.gov (ID: NCT05492487) on April 7, 2022: https://clinicaltrials.gov/study/NCT05492487 .

Metformin for endometrial hyperplasia

BACKGROUND

Endometrial cancer is one of the most common gynaecological cancers in the world. Rates of endometrial cancer are rising, in part because of rising obesity rates. Endometrial hyperplasia is a precancerous condition in women that can lead to endometrial cancer if left untreated. Endometrial hyperplasia occurs more commonly than endometrial cancer. Progesterone tablets that are currently used to treat women with endometrial hyperplasia are associated with adverse effects in up to 84% of women. A levonorgestrel intrauterine device may improve compliance, but it is invasive, is not acceptable to all women, and is associated with irregular vaginal bleeding in 82% of cases. Therefore, an alternative treatment for women with endometrial hyperplasia is needed. Metformin, a drug that is often used to treat people with diabetes, has been shown, in some human studies, to reverse endometrial hyperplasia. However, the effectiveness and safety of metformin for treatment of endometrial hyperplasia remain uncertain. This is an update of a review first published in 2017.

OBJECTIVES

To determine the effectiveness and safety of metformin in treating women with endometrial hyperplasia.

SEARCH METHODS

We searched the Cochrane Gynaecology and Fertility Specialised Register, CENTRAL, MEDLINE, PubMed, Embase, Google Scholar, OpenGrey, LILACS, and two trials registers from inception to 5 September 2022. We searched the bibliographies of all relevant studies, and contacted experts in the field for any additional trials.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) and cross-over trials comparing metformin (used alone or in combination with other medical therapies) versus placebo, no treatment, any conventional medical treatment, or any other active intervention for women with histologically confirmed endometrial hyperplasia of any type.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed studies for eligibility, extracted data from included studies, assessed the risk of bias in the included studies, and assessed the certainty of the evidence for each outcome. We resolved disagreements by discussion or by deferring to a third review author. When study details were missing, review authors contacted the study authors. The primary outcome of this review was regression of endometrial hyperplasia histology (with or without atypia) towards normal histology.

MAIN RESULTS

We included seven RCTs, in which a total of 387 women took part. In the comparison, Metformin plus megestrol versus megestrol alone, we rated the certainty of the evidence as low for the outcome, regression of endometrial hyperplasia. We rated the quality of the evidence as very low for the rest of the outcomes, in all three comparisons. Although there was a low risk of selection bias, there was a high risk of bias in the blinding of personnel and outcome assessment (performance bias and detection bias) in many studies. This update identified four new RCTs and six ongoing RCTs. Metformin versus megestrol We are uncertain whether metformin increases the regression of endometrial hyperplasia towards normal histology over megestrol (odds ratio (OR) 4.89, 95% confidence interval (CI) 1.56 to 15.32; P = 0.006; 2 RCTs, 83 participants; I² = 7%; very low-certainty evidence). This evidence suggests that if the rate of regression with megestrol is 61%, the rate of regression with metformin would be between 71% and 96%. It is unresolved whether metformin results in different rates of abnormal uterine bleeding or hysterectomy compared to megestrol. No study in this comparison reported progression of hyperplasia to endometrial cancer, recurrence of endometrial hyperplasia, health-related quality of life, or adverse effects during treatment. Metformin plus megestrol versus megestrol monotherapy The combination of metformin and megestrol may enhance the regression of endometrial hyperplasia towards normal histology more than megestrol alone (OR 3.27, 95% CI 1.65 to 6.51; P = 0.0007; 4 RCTs, 258 participants; I² = 0%, low-certainty evidence). This suggests that if the rate of regression with megestrol monotherapy is 54%, the rate of regression with the addition of metformin would be between 66% and 84%. In one study, 3/8 (37.5%) of participants who took metformin had nausea that settled without further treatment. It is unresolved whether the combination of metformin and megestrol results in different rates of recurrence of endometrial hyperplasia, progression of endometrial hyperplasia to endometrial cancer, or hysterectomy compared to megestrol monotherapy. No study in this comparison reported abnormal uterine bleeding, or health-related quality of life. Metformin plus levonorgestrel (intrauterine system) versus levonorgestrel (intrauterine system) monotherapy We are uncertain whether there is a difference between groups in the regression of endometrial hyperplasia towards normal histology (OR 0.29, 95% CI 0.01 to 7.56; 1 RCT, 46 participants; very low-certainty evidence). This evidence suggests that if the rate of regression with levonorgestrel monotherapy is 96%, the rate of regression with the addition of metformin would be between 73% and 100%. It is unresolved whether the combination of metformin and levonorgestrel results in different rates of abnormal uterine bleeding, hysterectomy, or the development of adverse effects during treatment compared to levonorgestrel monotherapy. No study in this comparison reported recurrence of endometrial hyperplasia, progression of hyperplasia to endometrial cancer, or health-related quality of life.

AUTHORS' CONCLUSIONS

Review authors found insufficient evidence to either support or refute the use of metformin, specifically megestrol acetate, given alone or in combination with standard therapy, for the treatment of women with endometrial hyperplasia. Robustly designed and adequately powered randomised controlled trials, yielding long-term outcome data are still needed to address this clinical question.

Management of Endometrial Intraepithelial Neoplasia or Atypical Endometrial Hyperplasia: ACOG Clinical Consensus No. 5

SUMMARY

Endometrial intraepithelial neoplasia (EIN) or atypical endometrial hyperplasia (AEH) often is a precursor lesion to adenocarcinoma of the endometrium. Hysterectomy is the definitive treatment for EIN-AEH. When a conservative (fertility-sparing) approach to the management of EIN-AEH is under consideration, it is important to attempt to exclude the presence of endometrial cancer to avoid potential undertreatment of an unknown malignancy in those who have been already diagnosed with EIN-AEH. Given the high risk of progression to cancer, those who do not have surgery require progestin therapy (oral, intrauterine, or combined) and close surveillance. Although data are conflicting and limited, studies have demonstrated that treatment with the levonorgestrel-releasing intrauterine device results in a higher regression rate when compared with treatment with oral progestins alone. Limited data suggest that cyclic progestational agents have lower regression rates when compared with continuous oral therapy. After initial conservative treatment for EIN-AEH, early detection of disease persistence, progression, or recurrence requires careful follow-up. Gynecologists and other clinicians should counsel patients that lifestyle modification resulting in weight loss and glycemic control can improve overall health and may decrease the risk of EIN-AEH and endometrial cancer.

Progestin plus metformin improves outcomes in patients with endometrial hyperplasia and early endometrial cancer more than progestin alone: a meta-analysis

Objective

Progestin based therapy is the preferred option for fertility-sparing treatment of reproductive-age women with preserved fertility in endometrial hyperplasia (EH) or early endometrial cancer (EEC). Our objective was to investigate whether metformin could enhance the efficacy of progestin-based therapies by meta-analysis.

Methods

We conducted a meta-analysis of randomized or non-randomized controlled trials by searching of PubMed, Embase, Web of science, and Cochrane database from inception to November 8, 2022. The results of enrolled studies were pooled using meta-analysis to estimate the effect of progestin plus metformin on remission, recurrence, pregnancy rate and live birth rate.

Results

In the analysis of progestin administered systemically or locally, complete response (CR) was significantly higher in progestin plus metformin versus progestin alone in the EH group (pooled OR 2.08, 95% CI 1.29 to 3.34, P=0.003), in the EEC group (pooled OR 1.86, 95% CI 1.13 to 3.05, P=0.01), but not in EEC and EH group (pooled OR 1.46, 95% CI 0.97 to 2.21, P=0.07). In the analysis of progestin administered systemically, complete response was improved in progestin plus metformin versus progestin alone, in the EH group (pooled OR 2.47, 95% CI 1.45 to 4.21, P=0.0009), in the EEC group (pooled OR 2.09, 95% CI 1.18 to 3.71, P=0.01), and in the EEC and EH group (pooled OR 2.03, 95% CI 1.16 to 3.54, P=0.01). The relapse rates of patients with EEC and EH were not different (pooled OR 0.54, 95% CI 0.24 to 1.20, P=0.13). For obstetric outcomes, the addition of metformin improved pregnancy rate (pooled OR 1.55, 95% CI 0.99 to 2.42, P=0.05), but not live birth rate (pooled OR 0.95, 95% CI 0.45 to 2.01, P=0.89).

Conclusion

For fertility-sparing management, compared to progestin alone, the outcomes of patients with endometrial hyperplasia and early endometrial cancer were more improved with progestin plus metformin because progestin plus metformin increases the rate of remission and pregnancy.

Improving the Diagnosis of Endometrial Hyperplasia Using Computerized Analysis and Immunohistochemical Biomarkers

Endometrial hyperplasia (EH) is a precursor lesion to endometrial carcinoma (EC). Risks for EC include genetic, hormonal and metabolic factors most notably those associated with obesity: rates are rising and there is concern that cases in pre-menopausal women may remain undetected. Making an accurate distinction between benign and pre-malignant disease is both a challenge for the pathologist and important to the gynecologist who wants to deliver the most appropriate care to meet the needs of the patient. Premalignant change may be recognized by histological changes of endometrial hyperplasia (which may occur with or without atypia) and endometrial intraepithelial neoplasia (EIN). In this study we created a tissue resource of EH samples diagnosed between 2004 and 2009 (n = 125) and used this to address key questions: 1. Are the EIN/WHO2014 diagnostic criteria able to consistently identify premalignant endometrium? 2. Can computer aided image analysis inform identification of EIN? 3. Can we improve diagnosis by incorporating analysis of protein expression using immunohistochemistry. Our findings confirmed the inclusion of EIN in diagnostic criteria resulted in a better agreement between expert pathologists compared with the previous WHO94 criteria used for the original diagnosis of our sample set. A computer model based on assessment of stromal:epithelial ratio appeared most accurate in classification of areas of tissue without EIN. From an extensive panel of putative endometrial protein tissue biomarkers a score based on assessment of HAND2, PTEN, and PAX2 was able to identify four clusters one of which appeared to be more likely to be benign. In summary, our study has highlighted new opportunities to improve diagnosis of pre-malignant disease in endometrium and provide a platform for further research on this important topic.

Metformin: Sex/Gender Differences in Its Uses and Effects—Narrative Review

Metformin (MTF) occupies a major and fundamental position in the therapeutic management of type 2 diabetes mellitus (T2DM). Gender differences in some effects and actions of MTF have been reported. Women are usually prescribed lower MTF doses compared to men and report more gastrointestinal side effects. The incidence of cardiovascular events in women on MTF has been found to be lower to that of men on MTF. Despite some promising results with MTF regarding pregnancy rates in women with PCOS, the management of gestational diabetes, cancer prevention or adjunctive cancer treatment and COVID-19, most robust meta-analyses have yet to confirm such beneficial effects.

Women's Risk Perceptions and Willingness to Engage in Risk-Reducing Interventions for the Prevention of Obesity-Related Endometrial Cancer

Introduction

Endometrial cancer rates are rising in parallel with the global obesity epidemic. Our aim was to assess the willingness of women at greatest risk of obesity-related endometrial cancer to engage with risk-reducing strategies and establish perceived barriers that may preclude their participation in a randomized controlled trial of primary endometrial cancer prevention.

Materials and Methods

Women attending gynecology, obesity and sleep apnea clinics in Manchester Academic Health Sciences Centre-affiliated hospitals with obesity classes II (BMI 35–39.9kg/m²) and III (BMI ≥40kg/m²) were invited to participate in a cross-sectional survey. We asked women about their perceived risk, knowledge of risk factors and willingness to engage with endometrial cancer risk-reducing interventions.

Results

Seventy-four women with a median age of 51 years (range 22–73) and BMI of 47kg/m² (range 34–81) took part in the study. Two-thirds (65.6%) knew that obesity was a risk factor for endometrial cancer but few were able to recall other major risk factors. Just over half (53.5%) perceived their risk of developing endometrial cancer to be higher than average. Women were prepared to lose weight (94%), eat healthily (91%), exercise more (87%), take a pill every day (74%) or receive an intra-uterine device (49%) for primary endometrial cancer prevention. Perceived barriers included cost, forgetting, willpower, finding time, physical fitness, social anxiety, possible side effects and previous bad experiences.

Conclusion

Women at highest risk of obesity-related endometrial cancer may not always appreciate their susceptibility. However, willingness to engage in risk-reducing strategies suggests recruitment to a randomized controlled trial for primary endometrial cancer prevention could be feasible.

Endometrial hyperplasia as a risk factor of endometrial cancer

Endometrial hyperplasia (EH) is the precursor lesion for endometrioid adenocarcinoma of the endometrium (EC), which represents the most common malignancy of the female reproductive tract in industrialized countries. The most important risk factor for the development of EH is chronic exposure to unopposed estrogen. Histopathologically, EH can be classified into EH without atypia (benign EH) and atypical EH/endometrial intraepithelial neoplasia (EIN). Clinical management ranges from surveillance or progestin therapy through to hysterectomy, depending on the risk of progression to or concomitant EC and the patient´s desire to preserve fertility. Multiple studies support the efficacy of progestins in treating both benign and atypical EH. This review summarizes the evidence base regarding risk factors and management of EH. Additionally, we performed a systematic literature search of the databases PubMed and Cochrane Controlled Trials register for studies analyzing the efficacy of progestin treatment in women with EH.

A Prospective Cohort Study of Metformin as an Adjuvant Therapy for Infertile Women With Endometrial Complex Hyperplasia/Complex Atypical Hyperplasia and Their Subsequent Assisted Reproductive Technology Outcomes

OBJECTIVE

To investigate the adjuvant efficacy of metformin treatment to achieve pathological complete response (CR) in patients with endometrial complex hyperplasia (CH) and complex atypical hyperplasia (CAH), and secondarily, to evaluate their pregnancy outcomes after following assisted reproductive technology (ART).

STUDY DESIGN

This prospective cohort study analyzed 219 patients diagnosed with infertility and CH/CAH from January 2016 to December 2020. Among these patients, 138 were assigned to the control group (progesterone alone) and 81 were assigned to the study group (progesterone+metformin). After 8/12 weeks of therapy, the treatment responses were assessed by histological examination of curettage specimens obtained by hysteroscopy. Once the pathological results indicated CR, the patients were able to receive ART. The ART treatment and follow-up data of these patients were collected and analyzed.

RESULTS

116 patients in the control group achieved CR, compared with 76 patients in the study group. The CR rate in the control group was significantly lower than that in the study group (P=0.034). We then divided the patients into subgroups to compare the treatment responses. In the subgroup analyses, patients with body mass index (BMI) ≥25 kg/m² and patients with polycystic ovarian syndrome (PCOS) had higher CR rates in the metformin group compared with the control group (P=0.015, P=0.028 respectively). Subsequently, 68 patients in the control group and 47 patients in the study group received an ART cycle. We examined the pregnancy indications and found no significant differences in the clinical pregnancy rate and live birth rate between the two groups (P>0.05).

CONCLUSION

Regression of CH/CAH may be improved by progesterone+metformin compared with progesterone alone. The effect was particularly pronounced in patients with BMI ≥25 kg/m² and patients with PCOS. Metformin had no obvious effect on subsequent ART outcomes. The trial is registered on the publicly accessible website.

CLINICAL TRIAL REGISTRATION

http://www.chictr.org.cn/showproj.aspx?proj=15372, identifier ChiCTR-ONR-16009078.

Outcomes of women treated with progestin and metformin for atypical endometrial hyperplasia and early endometrial cancer: a systematic review and meta-analysis

OBJECTIVE

Progestin therapy is the recommended fertility-sparing management of atypical endometrial hyperplasia or early-stage endometrial cancer in reproductive-aged women. Our objective was to evaluate disease relapse after progestin and metformin versus progestin therapy alone in patients with endometrial hyperplasia or cancer. Our secondary outcomes were disease remission, clinical pregnancy and live birth rate.

METHODS

A systematic review of the literature was conducted (MEDLINE, Web of Science, Cochrane Library, CINAHL, LILACS, clinicaltrials.gov) from inception to April 2021. Studies of reproductive-aged women with atypical endometrial hyperplasia or early endometrial cancer who received progestin and metformin or progestin alone for fertility-sparing management, were included in the review. Early endometrial cancer was defined as grade 1, stage 1 disease. Exclusion criteria included women with higher grade endometrial cancer and when conservative management was not for fertility-sparing purposes. Data are presented as odds ratios (ORs) and 95% confidence intervals (CIs) with fixed or random effects meta-analysis. Quality scoring was based on the Newcastle-Ottawa and Jadad scales.

RESULTS

In total, 271 reports were identified and six studies met the inclusion criteria. These studies included 621 women; 241 (38.8%) patients received combined therapy and 380 (61.2%) received progestin therapy alone. Relapse rates were lower for progestin and metformin than for progestin therapy alone (pooled OR 0.46, 95% CI 0.24 to 0.91, p=0.03). The remission rates were not different (pooled OR 1.35, 95% CI 0.91 to 2.00, p=0.14). Women who received progestin and metformin achieved pregnancy and live birth rates similar to those who received progestin therapy only (pooled OR 1.01, 95% CI 0.44 to 2.35, p=0.98; pooled OR 0.46, 95% CI 0.21 to 1.03, p=0.06).

CONCLUSION

For reproductive-aged women with atypical endometrial hyperplasia or early endometrial cancer, progestin and metformin therapy compared with progestin therapy alone is associated with lower relapse rates, and similar remission, clinical pregnancy and live birth rates.

PROSPERO REGISTRATION NUMBER

CRD42020179069.disease remission.

Pharmaceuticals targeting signaling pathways of endometriosis as potential new medical treatment: A review

Endometriosis (EM) is defined as endometrial tissues found outside the uterus. Growth and development of endometriotic cells in ectopic sites can be promoted via multiple pathways, including MAPK/MEK/ERK, PI3K/Akt/mTOR, NF-κB, Rho/ROCK, reactive oxidative stress, tumor necrosis factor, transforming growth factor-β, Wnt/β-catenin, vascular endothelial growth factor, estrogen, and cytokines. The underlying pathophysiological mechanisms include proliferation, apoptosis, autophagy, migration, invasion, fibrosis, angiogenesis, oxidative stress, inflammation, and immune escape. Current medical treatments for EM are mainly hormonal and symptomatic, and thus the development of new, effective, and safe pharmaceuticals targeting specific molecular and signaling pathways is needed. Here, we systematically reviewed the literature focused on pharmaceuticals that specifically target the molecular and signaling pathways involved in the pathophysiology of EM. Potential drug targets, their upstream and downstream molecules with key aberrant signaling, and the regulatory mechanisms promoting the growth and development of endometriotic cells and tissues were discussed. Hormonal pharmaceuticals, including melatonin, exerts proapoptotic via regulating matrix metallopeptidase activity while nonhormonal pharmaceutical sorafenib exerts antiproliferative effect via MAPK/ERK pathway and antiangiogenesis activity via VEGF/VEGFR pathway. N-acetyl cysteine, curcumin, and ginsenoside exert antioxidant and anti-inflammatory effects via radical scavenging activity. Natural products have high efficacy with minimal side effects; for example, resveratrol and epigallocatechin gallate have multiple targets and provide synergistic efficacy to resolve the complexity of the pathophysiology of EM, showing promising efficacy in treating EM. Although new medical treatments are currently being developed, more detailed pharmacological studies and large sample size clinical trials are needed to confirm the efficacy and safety of these treatments in the near future.

Differential Expressions of Ki-67, Bcl-2, and Apoptosis Index in Endometrial Cells of Women With and Without Type II Diabetes Mellitus and Their Correlation with Clinicopathological Variables

The objective of this study was to investigate proliferation, apoptosis, and antiapoptotic molecule expression in endometrial cells of reproductive-aged women with and without type II diabetes mellitus (T2D). In this case-control study, a total of 80 endometrial tissue specimens from reproductive-aged women (35 in the proliferative phase and 45 in the secretory phase) were examined. The age and body mass index (BMI) were matched between the groups. Formalin-fixed and paraffin-embedded endometrial tissue samples were used for immunohistochemistry analysis. The presence of proliferation was evaluated with Ki-67 expression, antiapoptotic function of cells was evaluated with Bcl-2 expression, and apoptosis was evaluated with terminal deoxynucleotidyl transferase (TUNEL) immunoreactivity in both the glandular epithelium and stroma of endometrial tissue samples from women with and without T2D. Ki-67 expression in the glandular epithelium and Bcl-2 expression in both the glandular epithelium and stroma were significantly higher in endometrial tissue samples of women in the T2D group than the control group (p = 0.0008, p = 0.0022, and p = 0.0261, respectively). TUNEL immunoreactivity was significantly lower in the glandular epithelium of women in the T2D group than the control group (p = 0.0001). Glandular Ki-67 expression correlated positively with BMI, use of insulin, and hemoglobin A1c level (p = 0.0034, p = 0.0154, and p = 0.0011, respectively). Glandular Bcl-2 expression correlated positively with BMI and duration of T2D (p = 0.0090 and p = 0.0109, respectively). Stromal Bcl-2 expression correlated positively with duration of T2D (p = 0.0069). TUNEL immunoreactivity in the glandular epithelium correlated negatively with duration of T2D (p = 0.0340) and positively with the use of oral antidiabetic agents (p = 0.0226). Compared to age and BMI-matched controls, women with T2D experienced increased cell proliferation and decreased apoptosis in the glandular epithelium and increased antiapoptotic function in both the glandular epithelium and stromal cells. High BMI values in women with diabetes seemed to contribute to increased cell proliferation and increased antiapoptotic function in the glandular epithelium but not the stromal cells.

Polycystic Ovary Syndrome and the Forgotten Uterus

Polycystic ovary syndrome (PCOS) is a common disorder that affects various facets of fertility. Although the ovarian and metabolic aspects of the disease is well studied, its role in uterine dysfunction is not well understood. Our objective was to review the features of endometrial and uterine aberrations in women with PCOS. A systematic literature search was performed in PubMed, Medline, and the Cochrane Library databases for papers published in English up to March 2020. The following key words were used for the search: polycystic ovary syndrome, poly cystic ovarian disease, polycystic ovaries, PCOS, PCOD, PCO, PCOM, oligoovulation, anovulation, oligomenorrhea, amenorrhea, hyperandrogenism and this was combined with terms; endometrium, infertility, uterus, progesterone resistance, endometrial hyperplasia, pregnancy outcomes, preterm delivery. In this review, we highlight various uterine pathologies that are associated with PCOS and explore its impact on fertility. We also discuss key uterine molecular pathways that are altered in PCOS that may be related to infertility, endometrial hyperplasia and cancer.

Route-specific association of progestin therapy and concurrent metformin use in obese women with complex atypical hyperplasia

INTRODUCTION

Previous studies have suggested that metformin use may enhance the therapeutic effect of progestin therapy for endometrial hyperplasia or malignancy. However, it is not known how the impact of concurrent metformin may be altered by route of progestin therapy, either locally via an intrauterine device or systemically. This study examined the effectiveness of concurrent metformin use and progestin therapy for women with complex atypical hyperplasia stratified by progestin route (systemic vs local).

METHODS

This single-institution retrospective study examined consecutive women with complex atypical hyperplasia who received progestin therapy from 2003 to 2018. Time-dependent analyses for complete response rate were performed comparing concurrent metformin users versus non-users in the oral progestin group and in the levonorgestrel-releasing intrauterine device group.

RESULTS

Across the study cohort (n=245), there were 137 (55.9%) women who responded to progestin therapy. In the oral progestin group (n=176), the median age and body mass index were 36 years and 37.7 kg/m2, respectively. 36 (20.5%) of women on oral progestins also took metformin. After controlling for diabetes status, women taking both oral progestins and metformin had a complete response rate similar to those not taking metformin (6 month cumulative rates, 23.1% vs 27.8%, adjusted hazard ratio (aHR) 0.71, 95% confidence interval (95% CI) 0.36 to 1.41). In the levonorgestrel-releasing intrauterine device group (n=69), the median age and body mass index were 35 years and 39.9 kg/m2, respectively. There were 15 (21.7%) women who took metformin in addition to the levonorgestrel-releasing intrauterine device. After controlling for diabetes status, women who had the levonorgestrel-releasing intrauterine device and took metformin had a significantly higher complete response rate compared with those not taking metformin (6 month cumulative rates, 86.7% vs 58.9%, aHR 2.31, 95% CI 1.09 to 4.89).

CONCLUSION

In a predominantly obese population, concurrent metformin may possibly offer treatment benefit when used with the levonorgestrel-releasing intrauterine device.

Therapeutic effect of metformin in the treatment of endometrial cancer

The present review aims at reviewing the role of metformin in the treatment of endometrial cancer (EC). According to the literature, excessive estrogen levels and insulin resistance are established risk factors of EC. As a traditional insulin sensitizer and newly discovered anticancer agent, metformin directly and indirectly inhibits the development of EC. The direct mechanisms of metformin include inhibition of the LKB1-AMP-activated protein kinase-mTOR, PI3K-Akt and insulin-like growth factor 1-related signaling pathways, which reduces the proliferation and promotes the apoptosis of EC cells. In the indirect mechanism, metformin increases the insulin sensitivity of body tissues and decreases circulating insulin levels. Decreased levels of insulin increase the blood levels of sex hormone binding globulin, which leads to reductions in circulating estrogen and androgens. The aforementioned findings suggest that metformin serves an important role in the treatment of EC. Increased understanding of the mechanism of metformin in EC may provide novel insights into the treatment of this malignancy.

PRE-surgical Metformin In Uterine Malignancy (PREMIUM): a Multi-Center, Randomized Double-Blind, Placebo-Controlled Phase III Trial

PURPOSE

Endometrioid endometrial cancer is strongly associated with obesity and insulin resistance. Metformin, an insulin sensitizer, reduces endometrial tumor growth in vitro. Presurgical window studies allow rapid in vivo assessment of antitumor activity. Previous window studies found metformin reduced endometrial cancer proliferation but these lacked methodological rigor. PREMIUM measured the anti-proliferative effect of metformin in vivo using a robust window study design.Patients and Methods: A multicenter, double-blind, placebo-controlled trial randomized women with atypical hyperplasia or endometrioid endometrial cancer to receive metformin (850 mg daily for 3 days, and twice daily thereafter) or placebo for 1 to 5 weeks until surgery. The primary outcome was posttreatment IHC expression of Ki-67. Secondary outcomes investigated the effect of metformin on markers of the PI3K-Akt-mTOR and insulin signaling pathways and obesity.

RESULTS

Eighty-eight women received metformin (n = 45) or placebo (n = 43) and completed treatment. There was no overall difference in posttreatment Ki-67 between the metformin and placebo arms, in an ANCOVA analysis adjusting for baseline Ki-67 expression (mean difference -0.57%; 95% CI, -7.57%-6.42%; P = 0.87). Metformin did not affect expression of markers of the PI3K-Akt-mTOR or insulin signaling pathways, and did not result in weight loss.

CONCLUSIONS

Short-term treatment with standard diabetic doses of metformin does not reduce tumor proliferation in women with endometrioid endometrial cancer awaiting hysterectomy. This study does not support a biological effect of metformin in endometrial cancer and casts doubt on its potential application in the primary and adjuvant treatment settings.