Prospective Randomized Biomarker Study of Metformin and Lifestyle Intervention for Prevention in Obese Women at Increased Risk for Endometrial Cancer

Diabetes mellitus complications associated with recurrence of stage I endometrioid endometrial cancer: A single-center retrospective study

OBJECTIVE

Identifying clinical features that are associated with recurrence of endometrioid endometrial carcinoma (EEC) in patients with diabetes mellitus (DM).

METHODS

A single-center retrospective cohort study was performed on patients with a diagnosis of both DM and Stage I EEC. Clinical and pathologic features were analyzed in relation to 5-year progression free survival (PFS). Kaplan-Meier Curves and Cox proportional hazard ratios were utilized to assess effect on 5-year PFS.

RESULTS

A total of 539 patients were included, with biopsy proven recurrence in 86 (18 %), and 456 (82 %) with no evidence of recurrence. Age, BMI, HgbA1c, metformin use, number of antihyperglycemic medications, use of adjuvant radiation, and surgical approach were not associated with differences in PFS. Presence of end-organ complications associated with diabetes was correlated with worse PFS (HR 1.78, 95 % CI 1.1-2.9, P = 0.02), and specifically diabetic neuropathy was associated with higher rates of recurrence (HR 3.6, 95 % CI 2.1-6.2, P < 0.01). In this cohort, PFS was independently associated with extent of myoinvasion (HR 2.33, 95 % CI 1.4-3.7, P < 0.01) as well as both microsatellite instability (HR 3.43, 95 % CI 1.8-6.6, P < 0.01), and no specific molecular profile (HR 0.3, 95 % CI 0.2-0.6, P < 0.01) molecular subtypes.

CONCLUSIONS

In patients with DM and EEC, extent of myoinvasion and TCGA molecular subtype correlated with worse PFS. Control of DM as evidenced by HgbA1c, BMI, and use of antihyperglycemic medications did not correlate with PFS in our cohort of patients with Stage I EEC, while the presence of diabetic neuropathy was associated with a higher risk of recurrence. These results highlight importance of evaluating diabetes severity and molecular subtype in endometrial cancer patients.

Metformin treatment of juvenile mice alters aging-related developmental and metabolic phenotypes in sex-dependent and sex-independent manners

Metformin has attracted increasing interest for its potential benefits in extending healthspan and longevity. This study examined the effects of early-life metformin treatment on the development and metabolism of C57BL/6 J (B6) mice, with metformin administered to juvenile mice from 15 to 56 days of age. Metformin treatment led to decreased body weight in both sexes (P < 0.05, t-test). At 9 weeks of age, mice were euthanized and organ weights were recorded. The relative weight of retroperitoneal fat was decreased in females, while relative weights of perigonadal and retroperitoneal fat were decreased, and relative liver weight was increased in males (P < 0.05, t-test). Glucose and insulin tolerance tests (GTT and ITT) were conducted at the age of 7 weeks. ANOVA revealed a significant impairment in insulin sensitivity by the treatment, and a significantly interactive effect on glucose tolerance between sex and treatment, underscoring a disparity in GTT between sexes in response to the treatment. Metformin treatment reduced circulating insulin levels in fasting and non-fasting conditions for male mice, with no significant alterations observed in female mice. qRT-PCR analysis of glucose metabolism-related genes (Akt2, Glut2, Glut4, Irs1, Nrip1, Pi3k, Pi3kca, Pkca) in the liver and skeletal muscle reveals metformin-induced sex- and organ-specific effects on gene expression. Comparison with previous studies in heterogeneous UM-HET3 mice receiving the same treatment suggests that genetic differences may contribute to variability in the effects of metformin treatment on development and metabolism. These findings indicate that early-life metformin treatment affects development and metabolism in both sex- and genetics-dependent manners.

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.

Aptamers as Potential Therapeutic Tools for Ovarian Cancer: Advancements and Challenges

Ovarian cancer (OC) is the most common lethal gynecologic cause of death in women worldwide, with a high mortality rate and increasing incidence. Despite advancements in the treatment, most OC patients still die from their disease due to late-stage diagnosis, the lack of effective diagnostic methods, and relapses. Aptamers, synthetic, short single-stranded oligonucleotides, have emerged as promising anticancer therapeutics. Their ability to selectively bind to target molecules, including cancer-related proteins and receptors, has revolutionized drug discovery and biomarker identification. Aptamers offer unique insights into the molecular pathways involved in cancer development and progression. Moreover, they show immense potential as drug delivery systems, enabling targeted delivery of therapeutic agents to cancer cells while minimizing off-target effects and reducing systemic toxicity. In the context of OC, the integration of aptamers with non-coding RNAs (ncRNAs) presents an opportunity for precise and efficient gene targeting. Additionally, the conjugation of aptamers with nanoparticles allows for accurate and targeted delivery of ncRNAs to specific cells, tissues, or organs. In this review, we will summarize the potential use and challenges associated with the use of aptamers alone or aptamer-ncRNA conjugates, nanoparticles, and multivalent aptamer-based therapeutics for the treatment of OC.

The Role of Omentin-1 in Cancers Development and Progression

Adipose tissue serves as an energy store and is also an active endocrine organ, exerting activity that influences obesity-related processes through the production of regulatory proteins called adipokines or adipocytokines. Adipokines play important direct and indirect roles in the pathogenesis of insulin resistance, the regulation of local and systemic inflammatory processes, and related metabolic complications. There have been an increasing number of studies showing the relationship between some adipokines and carcinogenesis. This work reviews the current literature concerning the effects of omentin-1 on carcinogenesis.

The Role of Selected Adipocytokines in Ovarian Cancer and Endometrial Cancer

Due to their multidirectional influence, adipocytokines are currently the subject of numerous intensive studies. Significant impact applies to many processes, both physiological and pathological. Moreover, the role of adipocytokines in carcinogenesis seems particularly interesting and not fully understood. For this reason, ongoing research focuses on the role of these compounds in the network of interactions in the tumor microenvironment. Particular attention should be drawn to cancers that remain challenging for modern gynecological oncology-ovarian and endometrial cancer. This paper presents the role of selected adipocytokines, including leptin, adiponectin, visfatin, resistin, apelin, chemerin, omentin and vaspin in cancer, with a particular focus on ovarian and endometrial cancer, and their potential clinical relevance.

Sparing Is Caring: Hormonal Retreatment in Women with Recurrent Endometrial Cancer after Fertility Preservation Management-A Single Centre Retrospective Study

Fertility-sparing treatment (FTS) of endometrial cancer (EC) has a high rate of remission but also a high rate of relapse (10-88%). Many women still wish to conceive at the time of relapse, but results regarding retreatment are still lacking. This study aims to evaluate the safety, oncological and pregnancy outcomes of repeated FST in women with recurrent EC. This is a retrospective single-center study that recruited patients who had uterine recurrence after achieving a complete response (CR) with FST for FIGO stage IA, well-differentiated (G1), endometrioid EC. All eligible women underwent a second FST. Among 26 patients with recurrence, 6 decided to receive a hysterectomy and 20 received fertility-sparing retreatment. In total, 17 out of 20 women (85%) achieved a CR in a median time of 6 months. A total of 2/20 women showed a stable disease and continued the treatment for a further 6 months and finally achieved a CR. In total, 1/20 women showed disease progression and underwent demolitive surgery. After relapse and a CR, 14 patients attempted to become pregnant, among whom 7 became pregnant (pregnancy rate 50%-life birth rate 29%). Secondary FST is a safe and effective option for women who desire to preserve fertility after the recurrence of early-stage EC.

Progestin Resistance and Corresponding Management of Abnormal Endometrial Hyperplasia and Endometrial Carcinoma

With a younger tendency in morbidity age, endometrial cancer (EC) incidence has grown year after year. Worse, even more commonly occurring is endometrial hyperplasia (EH), which is a precancerous endometrial proliferation. For young women with early EC and EH who want to preserve fertility, progestin therapy has been utilized as a routine fertility-preserving treatment approach. Nevertheless, progestin medication failure in some patients is mostly due to progestin resistance and side effects. In order to further analyze the potential mechanisms of progestin resistance in EH and EC, to provide theoretical support for effective therapeutic strategies, and to lay the groundwork for searching novel treatment approaches, this article reviews the current therapeutic effects of progestin in EH and EC, as well as the mechanisms and molecular biomarkers of progestin resistance, and systematically expounds on the potential therapeutic methods to overcome progestin resistance.

The impact of obesity and adipokines on breast and gynecologic malignancies

The link between obesity and multiple disease comorbidities is well established. In 2003, Calle and colleagues presented the relationship between obesity and several cancer types, including breast, ovarian, and endometrial malignancies. Nearly, 20% of cancer-related deaths in females can be accounted for by obesity. Identifying obesity as a risk factor for cancer led to a focus on the role of fat-secreted cytokines, known as adipokines, on carcinogenesis and tumor progression. Early studies indicated that the adipokine leptin increases cell proliferation, invasion, and inhibition of apoptosis in multiple cancer types. As a greater appreciation of the obesity-cancer link has amassed, we now know that additional adipokines can impact tumorigenesis. A deeper understanding of the adipokine-activated signaling in cancer may identify new treatment strategies irrespective of obesity. Moreover, adipokines may serve as disease biomarkers, harnessing the potential of obesity-associated factors to serve as indicators of treatment response and disease prognosis. As studies investigating obesity and women's cancers continue to expand, it has become evident that breast, ovarian, and uterine cancers are distinctly impacted by adipokines. While complex, these distinct interactions may provide insight into cancer progression in these organs and new opportunities for targeted therapies. This review aims to organize and present the literature from the last 5 years investigating the mechanisms and implications of adipokine signaling in breast, endometrial, and ovarian cancers with a special focus on leptin and adiponectin.

The effectiveness of diet intervention in improving the metabolism of overweight and obese women: a systematic review and meta-analysis

OBJECTIVES

Dietary therapy may improve glucose and lipid metabolism function in women. However, there is no systematic review to investigate the association between metabolic effects and different dietary interventions in obese women. The main purpose of this study is to summarize the current literature and investigate whether different dietary interventions have an effect on glucose and metabolic indicators of overweight or obese women.

METHODS

We conducted a scoping review of randomized controlled trial (RCT) studies from 1991 to 2022 by adopting a systematic review and meta-analysis. The database includes Google Scholar, PubMed, Embase and Web of Science. Literature screening, data extraction, and quality assessment were independently completed by 2 researchers. Meta-analysis was performed with RevMan.

RESULTS

Twelve articles were extracted and the meta-analysis results showed that the mean difference of metabolic indexes of obese women before and after dietary intervention, including fasting glucose, fasting insulin, HOMA-IR (Homeostasis model assessment-insulin resistance), TG (triglyceride), TC (total cholesterol), LDL-C (low-density lipoprotein cholesterol), HDL-C (high-density lipoprotein cholesterol) are -0.13 [-0.15, -0.10], -2.41 [-3.44, -1.38], -0.13 [-0.15, -0.10], -21.71 [-24.19, -19.22], -21.71 [-24.19, -19.22], -13.29 [-17.86, -8.72], 3.31 [2.22, 4.40], respectively.

CONCLUSIONS

Different dietary interventions benefit glucose and lipid metabolism of overweight or obese women. Further study is needed to determine which specific dietary effects have the greatest effect on improving metabolic indicators.

Fertility-Sparing Treatment for Endometrial Cancer: Oncological and Obstetric Outcomes in Combined Therapies with Levonorgestrel Intrauterine Device

Simple Summary

This article discusses a retrospective study describing sixteen years of experience in the fertility-sparing treatment (FST) of endometrial cancer (EC) in a tertiary referral center for oncology. The aim of the study is to compare oncological and reproductive outcomes of different combined therapy with LNG-IUD in FST of presumed FIGO STAGE IA endometrioid G1 EC. We assessed outcomes for 75 patients treated with three different approaches: GnRH analogue (GnRHa) + LNG-IUD vs. Megestrol acetate (MA) + LNG-IUD vs. MA + LNG-IUD + Metformin (MET). We reported, although not statistically significant, an increasing rate of CR from the regimen with GnRHa to one with MA+MET (65% vs. 83%) and showed a statistically significant lower risk of recurrence in women treated with MA+ LNG-IUD+MET when compared to GnRHa+ LNG-IUD regimen. There were no differences in obstetric outcomes among different therapeutic regimens.

Abstract

Background: The prevalence of reaches up to 5% in women younger than 40 years. Therefore, the fertility preservation should be the goal of the clinical practice in women with desire of pregnancy and low-risk features. The aim of this study is to compare oncological and reproductive outcomes of different hormonal therapies in FST of EC. Methods: A retrospective single-center study recruiting patients with presumed FIGO STAGE IA endometrioid G1 EC from 2005 to 2020 was performed. We assessed outcomes for three different therapeutic options: GnRHa + LNG-IUD vs. MA + LNG-IUD vs. MA + LNG-IUD + MET. Results: In total, 75 patients were enrolled and followed up for a median of 45 months. Complete response (CR) was achieved in 75% of patients at 12 months. Although not statistically significant, we reported an increasing rate of CR from the regimen with GnRHa to the one with MA + MET (65% vs. 83%). We showed a statistically significant lower risk of recurrence in women treated with MA + LNG-IUD + MET, when compared to GnRHa + LNG-IUD regimen. The pregnancy rate was 74% and live birth rate was 42%, with no differences among regimens. Conclusions: FST is a safe and effective option in women who desire to preserve fertility.

Metformin Intervention—A Panacea for Cancer Treatment?

The molecular mechanism of action and the individual influence of various metabolic pathways related to metformin intervention are under current investigation. The available data suggest that metformin provides many advantages, exhibiting anti-inflammatory, anti-cancer, hepatoprotective, cardioprotective, otoprotective, radioprotective, and radio-sensitizing properties depending on cellular context. This literature review was undertaken to provide novel evidence concerning metformin intervention, with a particular emphasis on cancer treatment and prevention. Undoubtedly, the pleiotropic actions associated with metformin include inhibiting inflammatory processes, increasing antioxidant capacity, and improving glycemic and lipid metabolism. Consequently, these characteristics make metformin an attractive medicament to translate to human trials, the promising results of which were also summarized in this review.

Fertility-Sparing Approaches in Atypical Endometrial Hyperplasia and Endometrial Cancer Patients: Current Evidence and Future Directions

Endometrial cancer (EC) is the fourth most common cancer in women in developed countries. Although it is usually diagnosed in postmenopausal women, its incidence has increased in young women, as well in recent decades, with an estimated rate of 4% in those under 40 years of age. Factors involved in this increase, particularly in resource-rich countries, include delayed childbearing and the rise in obesity. The new molecular classification of EC should help to personalize treatment, through appropriate candidate selection. With the currently available evidence, the use of oral progestin either alone or in combination with other drugs such as metformin, levonorgestrel-releasing intrauterine devices and hysteroscopic resection, seems to be feasible and safe in women with early-stage EC limited to the endometrium. However, there is a lack of high-quality evidence of the efficacy and safety of conservative management in EC. Randomized clinical trials in younger women and obese patients are currently underway.

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.

Prevention of endometrial cancer through lifestyle Interventions: A systematic review and synthesis

Endometrial cancer is the most common gynaecological malignancy in Australia. Epidemiological studies have widely documented the association of endometrial cancer with modifiable lifestyle risk factors, most notably obesity. However, preventative strategies for endometrial cancer have not been well reported. The objective of this systematic review was to identify interventions targeted towards modifiable lifestyle risk factors that may reduce the risk of endometrial cancer. Literature published in the past ten years (January 2010 - January 2021) was retrieved from PubMed, Embase and Web of Science literature databases. Of 593 studies potentially eligible, 41 were assessed in full-text, and nine studies were included in the systematic review and synthesis without meta-analysis following the SWiM guidelines. The included studies were highly heterogenous with respect to the type of interventions implemented and the outcomes measured. We identified that diet and physical activity interventions, surgical weight loss interventions, and hormonal interventions were associated with changes in endometrial cancer biomarkers including circulating hormones and tissue markers. We identified a reduction in endometrial proliferation following lifestyle intervention as measured by the ki-67 proliferation index. Furthermore we identified an increase in adiponectin (a circulating biomarker of adiposity) following lifestyle intervention and a reduction in circulating insulin levels following lifestyle intervention. This review highlighted that the area of endometrial cancer prevention research is in its infancy and that further investigation of diet and physical activity interventions, surgical weight loss interventions, and hormonal interventions should be undertaken due to promising preliminary evidence.

Increased body mass index predicts prolonged survival in patients with head and neck squamous cell carcinoma

BACKGROUND

Higher body mass index (BMI) may have a protective effect on survival in patients with head and neck cancer. The aim of this study was to determine the effect of BMI on overall survival (OS) in veterans with head and neck squamous cell carcinoma (HNSCC).

METHODS

A cohort of 702 patients diagnosed with HNSCC between 1995 and 2019 were identified at the Washington DC Veterans Affairs Medical Center, and 342 patients were included for analysis. Records were queried for clinical-demographic data, BMI, and outcomes.

RESULTS

HNSCC patients categorized as overweight or obese at time of diagnosis had a lower 3-year risk of death (p = 0.033) and improved OS (p < 0.001) compared to patients who were underweight or normal weight. The majority of locoregional recurrences occurred in patients with low or normal pretreatment BMI.

CONCLUSIONS

Higher BMI at diagnosis may have a protective effect on OS in veterans with HNSCC.

Fertility-Sparing Approach in Women Affected by Stage I and Low-Grade Endometrial Carcinoma: An Updated Overview

Endometrial cancer (EC) is a deleterious condition which strongly affects a woman's quality of life. Although aggressive interventions should be considered to treat high-grade EC, a conservative approach should be taken into consideration for women wishing to conceive. In this scenario, we present an overview about the EC fertility-sparing approach state of art. Type I EC at low stage is the only histological type which can be addressed with a fertility-sparing approach. Moreover, no myometrium and/or adnexal invasion should be seen, and lymph-vascular space should not be involved. Regarding the pharmaceutical target, progestins, in particular medroxyprogesterone acetate (MPA) or megestrol acetate (MA), are the most employed agent in conservative treatment of early-stage EC. The metformin usage and hysteroscopic assessment is still under debate, despite promising results. Particularly strict and imperious attention should be given to the follow-up and psychological wellbeing of women, especially because of the double detrimental impairment: both EC and EC-related infertility consequences.

Biguanides drugs: Past success stories and promising future for drug discovery

Biguanides have attracted much attention a century ago and showed resurgent interest in recent years after a long period of dormancy. They constitute an important class of therapeutic agents suitable for the treatment of a wide spectrum of diseases. Therapeutic indications of biguanides include antidiabetic, antimalarial, antiviral, antiplaque, and bactericidal applications. This review presents an extensive overview of the biological activity of biguanides and different mechanisms of action of currently marketed biguanide-containing drugs, as well as their pharmacological properties when applicable. We highlight the recent developments in research on biguanide compounds, with a primary focus on studies on metformin in the field of oncology. We aim to provide a critical overview of all main bioactive biguanide compounds and discuss future perspectives for the design of new drugs based on the biguanide fragment.

The evolving role of targeted metformin administration for the prevention and treatment of endometrial cancer: A systematic review and meta-analysis of randomized controlled trials

AIM

The aim of the present study was to evaluate the role of metformin in endometrial cancer (EC), focusing on its potential preventive effect in breast cancer and obese patients and its safety and efficacy when added to progesterone monotherapy in EC patients who wish to preserve their fertility.

METHODS

We reviewed the literature and then conducted a meta-analysis of the relevant parameters.

RESULTS

A total of 6 studies was included in the meta-analysis. Regarding the pre-surgical treatment with metformin versus placebo, meta-analysis of mean difference in Ki-67 after treatment among two groups, revealed no difference (MD -7.10, 95% CI -23.31 to 9.11, p = 0.39). Meta-analysis of fertility sparing EC management with a combination of megestrol acetate (MA) and metformin (500 mg three times a day) in comparison with monotherapy with 160 mg daily MA revealed no difference in either complete response or partial response rates (166 patients OR 2.94, 95% CI 0.85 to 10.15, p = 0.09 and 166 patients OR 0.76, 95% CI 0.34 to 1.66, p = 0.49, respectively). As far as breast cancer survivors under tamoxifen are concerned, metformin was associated with significantly reduced median endometrial thickness after 52 weeks of evaluation compared to women in placebo group (2.3 mm vs 3.0 mm, p = 0.05).

CONCLUSIONS

Metformin neither was found to be an anti-proliferative agent against the development of endometrial cancer nor beneficial in addition to the progesterone monotherapy for EC fertility sparing candidates. However, a protective effect of metformin was demonstrated in breast cancer survivors under tamoxifen. Clinical outcomes of the ongoing trials are warranted to evaluate the therapeutic use of metformin in EC.

Complete pathological response following levonorgestrel intrauterine device in clinically stage 1 endometrial adenocarcinoma: Results of a randomized clinical trial

PURPOSE

Intrauterine levonorgestrel (LNG-IUD) is used to treat patients with endometrial adenocarcinoma (EAC) and endometrial hyperplasia with atypia (EHA) but limited evidence is available on its effectiveness. The study determined the extent to which LNG-IUD with or without metformin (M) or weight loss (WL) achieves a pathological complete response (pCR) in patients with EAC or EHA.

PATIENTS AND METHODS

This phase II randomized controlled clinical trial enrolled patients with histologically confirmed, clinically stage 1 FIGO grade 1 EAC or EHA; a body mass index > 30 kg/m2; a depth of myometrial invasion of less than 50% on MRI; a serum CA125 ≤ 30 U/mL. All patients received LNG-IUD and were randomized to observation (OBS), M (500 mg orally twice daily), or WL (pooled analysis). The primary outcome measure was the proportion of patients developing a pCR (defined as absence of any evidence of EAC or EHA) after 6 months.

RESULTS

From December 2012 to October 2019, 165 patients were enrolled and 154 completed the 6-months follow up. Women had a mean age of 53 years, and a mean BMI of 48 kg/m². Ninety-six patients were diagnosed with EAC (58%) and 69 patients with EHA (42%). Thirty-five participants were randomized to OBS, 36 to WL and 47 to M (10 patients were withdrawn). After 6 months the rate of pCR was 61% (95% CI 42% to 77%) for OBS, 67% (95% CI 48% to 82%) for WL and 57% (95% CI 41% to 72%) for M. Across the three treatment groups, the pCR was 82% and 43% for EHA and EAC, respectively.

CONCLUSION

Complete response rates at 6 months were encouraging for patients with EAC and EHA across the three groups.

TRIAL REGISTRATION

U.S. National Library of Medicine, NCT01686126.

Prospective phase II trial of levonorgestrel intrauterine device: nonsurgical approach for complex atypical hyperplasia and early-stage endometrial cancer

BACKGROUND

The incidence of complex atypical hyperplasia and early-stage endometrioid endometrial cancer is increasing, in part owing to the epidemic of obesity, which is a risk factor tightly linked to the development of endometrial hyperplasia and cancer. The standard upfront treatment for complex atypical hyperplasia and early-stage endometrial cancer is hysterectomy. However, nonsurgical treatment of early-stage endometrial neoplasia may be necessary owing to medical comorbidities precluding surgery or desired future fertility.

OBJECTIVE

This study aimed to evaluate the efficacy of the levonorgestrel intrauterine device to treat complex atypical hyperplasia and grade 1 endometrioid endometrial carcinoma.

STUDY DESIGN

A single-institution, single-arm, phase II study of the levonorgestrel intrauterine device (52 mg levonorgestrel, Mirena) was conducted in patients with complex atypical hyperplasia or grade 1 endometrioid endometrial cancer. The primary endpoint was pathologic response rate at 12 months, including complete or partial response. Quality of life and toxicity were assessed. Molecular analyses for proliferation markers, hormone-regulated genes, and wingless-related integration site pathway activation were performed at baseline and 3 months.

RESULTS

A total of 57 patients were treated (21 endometrial cancer, 36 complex atypical hyperplasia). The median age was 48.0 years, and the median body mass index was 45.5 kg/m². Of the 47 evaluable patients, 12-month response rate was 83% (90% credible interval, 72.7-90.3)-37 were complete responders (8 endometrial cancer; 29 complex atypical hyperplasia), 2 were partial responders (2 endometrial cancer), 3 had stable disease (2 endometrial cancer; 1 complex atypical hyperplasia), and 5 had progressive disease (3 endometrial cancer; 2 complex atypical hyperplasia). After stratification for histology, the response rate was 90.6% for complex atypical hyperplasia and 66.7% for grade 1 endometrioid endometrial cancer. Notably, 4 patients (9.5%) experienced relapse after the initial response. Adverse events were mild, primarily irregular bleeding and cramping. Quality of life was not negatively affected. At 3 months, exogenous progesterone effect was present in 96.9% of responders (31 of 32) vs 25% of nonresponders (2 of 8) (P=.001). Nonresponders had higher baseline proliferation (Ki67) and lower dickkopf homolog 3 gene expression than responders (P=.023 and P=.030). Nonresponders had significantly different changes in secreted frizzled-related protein 1, frizzled class receptor 8, and retinaldehyde dehydrogenase 2 compared with responders.

CONCLUSION

The levonorgestrel intrauterine device has a substantial activity in complex atypical hyperplasia and grade 1 endometrioid endometrial cancer, with a modest proportion demonstrating upfront progesterone resistance. Potential biomarkers were identified that may correlate with resistance to therapy; further exploration is warranted.

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.

Metformin: current clinical applications in nondiabetic patients with cancer

Metformin is one of the most commonly used first-line oral medications for type 2 diabetes mellitus. Multiple observational studies, reviewed in numerous systematic reviews, have shown that metformin treatment may not only reduce the risk of cancer but may also improve the efficacy of cancer treatment in diabetic patients. Recent studies have been conducted to determine whether a similar protective effect can be demonstrated in nondiabetic cancer patients. However, the results are controversial. The potential optimal dose, schedule, and duration of metformin treatment and the heterogeneity of histological subtypes and genotypes among cancer patients might contribute to the different clinical benefits. In addition, as the immune property of metformin was investigated, further studies of the immunomodulatory effect of metformin on cancer cells should also be taken into account to optimize its clinical use. In this review, we present and discuss the latest findings regarding the anticancer potential of metformin in nondiabetic patients with cancer.

Metformin Promotes Anti-tumor Biomarkers in Human Endometrial Cancer Cells

Metformin (MET) is increasingly implicated in reducing the incidence of multiple cancer types in patients with diabetes. However, similar effects of MET in non-diabetic women with endometrial cancer (EC) remain unknown. In a pilot study, obese non-diabetic women diagnosed with type 1, grade 1/2 EC, and consenting to participate were randomly assigned to receive MET or no MET (control (CON)) during the pre-surgical window between diagnosis and hysterectomy. Endometrial tumors obtained at surgery (MET, n = 4; CON, n = 4) were analyzed for proliferation (Ki67), apoptosis (TUNEL), and nuclear expression of ERα, PGR, PTEN, and KLF9 proteins in tumor glandular epithelial (GE) and stromal (ST) cells. The percentages of immunopositive cells for PGR and for KLF9 in GE and for PTEN in ST were higher while those for ERα in GE but not ST were lower, in tumors of MET vs. CON patients. The numbers of Ki67- and TUNEL-positive cells in tumor GE and ST did not differ between groups. In human Ishikawa endometrial cancer cells, MET treatment (60 μM) decreased cell numbers and elicited distinct temporal changes in ESR1, KLF9, PGR, PGR-B, KLF4, DKK1, and other tumor biomarker mRNA levels. In the context of reduced KLF9 expression (by siRNA targeting), MET rapidly amplified PGR, PGR-B, and KLF4 transcript levels. Our findings suggest that MET acts directly in EC cells to modify steroid receptor expression and signaling network and may constitute a preventative strategy against EC in high-risk non-diabetic women.

Endometrial cancer prevention in high-risk women

Endometrial cancer (EC) is the most common gynaecological malignancy, and its incidence is rising alongside the growing prevalence of obesity. Effective risk-reducing interventions hijacking the key mechanisms driving endometrial carcinogenesis may affect EC diagnoses if aimed at those at greatest risk. An understanding of the key risk factors and their role in tumourigenesis is critical in developing such prevention strategies. In this review, we summarise the major risk factors for EC and the evidence for available risk-reducing interventions in high-risk women. We suggest potential prevention strategies and make a case for the need for risk prediction models that identify specific groups of women at a particularly high risk of EC for whom risk-reducing interventions are likely to have a significant impact.

Prevention Strategies in Endometrial Carcinoma

PURPOSE OF THE REVIEW

To assess the most recent high-quality evidence for endometrial cancer prevention strategies.

RECENT FINDINGS

Obesity is an established risk factor for endometrial cancer. Weight cycling and weight gain in middle age are risk factors for endometrial cancer. Bariatric surgery reduces the risk of endometrial cancer by up to 81% in obese women who attain and maintain a normal weight. Combined oral contraceptives provide durable protection against endometrial cancer for 30 years or more. Ever use of the levonorgestrel intrauterine system (LNG-IUS) and inert intrauterine devices reduce endometrial cancer risk. The first oestrogen-based non-progestin HRT for non-hysterectomised women that contains estradiol and bazedoxifene has an effective protective effect on endometrium. Bisphosphonates reduce endometrial cancer risk. Weight loss and LNG-IUS would seem to be an effective strategy for preventing the development of obesity-driven endometrial cancer in the highest risk women. Future research may identify other safe and effective chemoprevention interventions, such as aspirin, bisphosphonates or metformin.