Reviewing the molecular mechanisms which increase endometrial cancer (EC) risk in women with polycystic ovarian syndrome (PCOS): Time for paradigm shift?

Deciphering the Role of Insulin-Like Growth Factor 1 in Endometrial Cancer in Patients With Polycystic Ovary Syndrome: Protocol for a Methodological Approach Using Cell Culture Experiments

BACKGROUND

Endometrial cancer (EC) is the most common gynecological cancer in women globally. It is linked to increasing obesity rates and longer life spans. The molecular mechanisms leading to EC are unclear; however, women with polycystic ovary syndrome (PCOS) have a 3- to 5-fold increased EC risk. According to a pilot study conducted in the United Kingdom, insulin-like growth factor-1 (IGF-1) gene and protein were raised in the endometrium and blood of women with EC and PCOS, compared with those without PCOS (controls). Therefore, raised serum IGF-1 levels may contribute to an increased EC risk in women with PCOS, but it is necessary to test this hypothesis since not all studies have demonstrated this association.

OBJECTIVE

This study aims to investigate the role of IGF-1 in mediating EC risk in PCOS. This will be achieved by evaluating the proliferative effects of PCOS serum, IGF-1, and IGF-1 antagonist on human endometrial cancer 1-A and 1-B cell lines, with a comparison to controls (using serum from women without PCOS and cell culture media). The study will also identify differentially expressed genes and pathways activated by various treatments.

METHODS

We intend to recruit 20 women with PCOS and 20 women without PCOS for this cross-sectional study. All experiments will be carried out 4 times to ensure consistency. We will perform transcriptomic and phosphoproteomic profiling to identify differentially expressed genes and phosphoproteins between different treatments using RNA sequencing and phosphoproteomics. We will also perform bioinformatics pathway analysis to identify whether any unique collection of genes or phosphoproteins explains increased EC risk in PCOS. The primary outcome measure will be the cell proliferation (growth) difference measured by cell index values. Our protocol stands out due to its unique approach; no previous study has used this approach to investigate the oncogenic effect of serum from women with PCOS. Additionally, no previous study has considered the differential mutations of genes related to the insulin signaling pathway across various types of human EC cell lines and the potential impact of these variations on their experimental findings.

RESULTS

Participants are currently being recruited. It is expected that preliminary findings suitable for analysis and publication will be available by the summer of 2024.

CONCLUSIONS

Although we currently do not have any results to report, sharing our protocol at this stage will aid in research collaboration, provide an opportunity for early feedback, and help reduce duplication of effort by other research groups. The findings of our study will have broader implications. A deeper understanding of the mechanisms underlying the regulation of the IGF system in PCOS and EC will improve our ability to develop effective treatment modalities for EC and will be a vital step toward reducing EC in women globally.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/48127.

Landscape of PCOS co-expression gene and its role in predicting prognosis and assisting immunotherapy in endometrial cancer

BACKGROUND

Endometrial carcinoma (EC) is the sixth most frequent malignancy in women and is often linked to high estrogen exposure. Polycystic ovarian syndrome (PCOS) is a known risk factor for EC, but the underlying mechanisms remain unclear.

METHODS

We investigated shared gene signals and potential biological pathways to identify effective therapy options for PCOS- and EC-related malignancies. Weighted gene expression network analysis (WGCNA) was used to identify genes associated with PCOS and EC using gene expression data from the Gene Expression Omnibus (GEO) and Cancer Genome Atlas (TCGA) datasets. Enrichment analysis using Cluego software revealed that the steroid hormone biosynthetic process was a critical feature in both PCOS and EC. A predictive signature encompassing genes involved in steroid hormone production was developed using multivariate and least absolute shrinkage and selection operator (LASSO) regression analysis to predict the prognosis of EC. Then, we conducted further experimental verification.

RESULTS

Patients in the TCGA cohort with high predictive scores had poorer outcomes than those with low scores. We also investigated the relationship between tumor microenvironment (TME) features and predictive risk rating and found that patients with low-risk scores had higher levels of inflammatory and inhibitory immune cells. Also, we found that immunotherapy against anti-CTLA4 and anti-PD-1/PD-L1 was successful in treating individuals with low risk. Low-risk individuals were more responsive to crizotinib therapy, according to further research performed using the "pRRophetic" R package. We further confirmed that IGF2 expression was associated with tumor cell migration, proliferation, and invasion in EC cells.

CONCLUTIONS

By uncovering the pathways and genes linking PCOS and EC, our findings may provide new therapeutic strategies for patients with PCOS-related EC.

Clinical and metabolic characteristics of endometrial lesions in polycystic ovary syndrome at reproductive age

BACKGROUND

We aimed to explore the clinical and metabolic characteristics in polycystic ovary syndrome (PCOS) patients with different endometrial lesions.

METHODS

234 PCOS patients who underwent hysteroscopy and endometrial biopsy were categorized into four groups: (1) normal endometrium (control group, n = 98), (2) endometrial polyp (EP group, n = 92), (3) endometrial hyperplasia (EH group, n = 33), (4) endometrial cancer (EC group, n = 11). Serum sex hormone levels, 75 g oral glucose tolerance test, insulin release test, fasting plasma lipid, complete blood count and coagulation parameters were measured and analyzed.

RESULTS

Body mass index and triglyceride level of the EH group were higher while average menstrual cycle length was longer in comparison with the control and EP group. Sex hormone-binding globulin (SHBG) and high density lipoprotein were lower in the EH group than that in the control group. 36% of the patients in the EH group suggested obesity, higher than the other three groups. Using multivariant regression analysis, patients with free androgen index > 5 had higher risk of EH (OR 5.70; 95% CI 1.05-31.01), while metformin appeared to be a protective factor for EH (OR 0.12; 95% CI 0.02-0.80). Metformin and hormones (oral contraceptives or progestogen) were shown to be protective factors for EP (OR 0.09; 95% CI 0.02-0.42; OR 0.10; 95% CI 0.02-0.56). Hormones therapy appeared to be a protective factor for EC (OR 0.05; 95% CI 0.01-0.39).

CONCLUSION

Obesity, prolonged menstrual cycle, decreased SHBG, and dyslipidemia are risk factors for EH in patients with PCOS. Oral contraceptives, progestogen and metformin are recommended for prevention and treatment of endometrial lesions in PCOS patients.

Polycystic ovary syndrome is associated with a higher risk of premalignant and malignant endometrial polyps in premenopausal women: a retrospective study in a tertiary teaching hospital

Background

Polycystic ovary syndrome (PCOS) is characterized by anovulation, insufficient progesterone, hyperandrogenism, and insulin resistance. These factors can disrupt the endometrium of PCOS patients and can lead to chronic low-grade inflammation in the endometrium, endometrial hyperplasia, or even endometrial cancer.

Objective

The aim of this study was to investigate the prevalence of premalignant and malignant endometrial polyps in premenopausal women and to further explore whether PCOS is associated with premalignant and malignant changes in endometrial polyps.

Methods

This study was conducted by retrieving the medical data of 4236 premenopausal women who underwent hysteroscopic polypectomies between January 2015 and December 2021. Demographic and clinical data regarding age, height, weight, parity, hormone replacement therapy, oral contraceptives, abnormal uterine bleeding, hypertension, diabetes mellitus, PCOS, number of polyps, and size of polyps were collected, and their associations with premalignant and malignant changes in endometrial polyps were analysed.

Result

Among the endometrial polyps removed by hysteroscopic polypectomy in premenopausal women, the prevalence of premalignant and malignant polyps was 2.15%, which comprised hyperplasia with atypia at 1.13% and endometrial carcinoma at 1.02%. PCOS was associated with a higher risk of premalignant and malignant endometrial polyps in premenopausal women after adjustment for potential confounding factors.

Conclusion

PCOS is associated with a higher risk of premalignant and malignant endometrial polyps in premenopausal women. Therefore, it is important to evaluate the endometrium in PCOS patients with ultrasonography or hysteroscopy, and active management involving hysteroscopic polypectomy should be offered to PCOS patients diagnosed with endometrial polyps regardless of symptoms.

Oncological and reproductive outcomes for gonadotropin-releasing hormone agonist combined with aromatase inhibitors or levonorgestrel-releasing intra-uterine system in women with endometrial cancer or atypical endometrial hyperplasia

OBJECTIVE

To evaluate the efficacy and safety of gonadotropin-releasing hormone agonist (GnRHa) combined with a levonorgestrel-releasing intrauterine device (LNG-IUD) or aromatase inhibitor (letrozole) in women with endometrial carcinoma or atypical endometrial hyperplasia who wished to preserve fertility.

METHODS

Patients at the Department of Obstetrics and Gynecology, Peking Union Medical College Hospital between January 2013 and December 2020 were retrospectively reviewed. A total of 179 patients who were unsuitable to undergo treatment with high-dose oral progestin, including those with progestin allergies, body mass index ≥30 kg/m2, liver and/or renal dysfunction, hypercoagulable state, and thrombosis were included. Patient data were retrieved from medical records and a prospectively maintained database that represented the standard protocol was followed for all patients. Clinical characteristics, treatment outcomes, adverse events, and reproductive outcomes were collected and analyzed. Logistic regression models were constructed to determine the associations between complete remission, recurrence, and fertility.

RESULTS

Overall, 169 patients (94.4%) achieved complete remission; 58 (96.7%) had atypical endometrial hyperplasia and 111 (93.3%) had endometrial carcinoma. The complete remission rates for the GnRHa plus LNG-IUD and GnRHa plus letrozole groups were 93.5% and 95.8%, respectively. The median time to complete remission was 6 (range 3-18) months: 4 (range 3-10) months for atypical endometrial hyperplasia and 8 (range 3-18) months for endometrial carcinoma. After a median follow-up of 27.5 (range 3-92) months, 41 (24.3%) women developed recurrence, with a median recurrence time of 17 (range 6-77) months. Of the patients with complete remission, 134 patients desired to conceive and 42 (32.3%) became pregnant, 24 (17.9%) were successfully delivered, 5 (3.7%) were still pregnant, while 13 miscarried.

CONCLUSION

GnRHa combined treatment provides favorable oncological and reproductive outcomes. Larger multi-institutional studies are required to confirm these preliminary findings.

Polycystic Ovary Syndrome and Endometrial Cancer: A Scoping Review of the Literature on Gut Microbiota

Gut dysbiosis has been associated with polycystic ovary syndrome (PCOS) and endometrial cancer (EC) but no studies have investigated whether gut dysbiosis may explain the increased endometrial cancer risk in polycystic ovary syndrome. The aim of this scoping review is to evaluate the extent and nature of published studies on the gut microbiota in polycystic ovary syndrome and endometrial cancer and attempt to find any similarities between the composition of the microbiota. We searched for publications ranging from the years 2016 to 2022, due to the completion date of the ‘Human Microbiome Project’ in 2016. We obtained 200 articles by inputting keywords such as ‘gut microbiome’, ‘gut microbiota’, ‘gut dysbiosis’, ‘PCOS’, and ‘endometrial cancer’ into search engines such as PubMed and Scopus. Of the 200 identified in our initial search, we included 25 articles in our final review after applying the exclusion and inclusion criteria. Although the literature is growing in this field, we did not identify enough published studies to investigate whether gut dysbiosis may explain the increased EC risk in PCOS. Within the studies identified, we were unable to identify any consistent patterns of the microbiome similarly present in studies on women with PCOS compared with women with EC. Although we found that the phylum Firmicutes was similarly decreased in women with PCOS and studies on women with EC, there was however significant variability within the studies identified making it highly likely that this may have arisen by chance. Further research pertaining to molecular and microbiological mechanisms in relation to the gut microbiome is needed to elucidate a greater understanding of its contribution to the pathophysiology of endometrial cancer in patients with polycystic ovarian syndrome.

Diabetes mellitus and endometrial carcinoma: Risk factors and etiological links

The presence of diabetes mellitus (DM) has a critical influence on the occurrence and development of endometrial cancer (EC) and is associated with a poor prognosis. Patients with DM are twice as likely to progress to EC, probably because a high-glucose environment contributes to the growth and invasiveness of EC cells. In this review, we focus on the etiological links between DM and EC and provide an overview of potential biological mechanisms that may account for this relationship, including hyperglycemia, insulin resistance, hyperinsulinemia, glycolysis, chronic inflammation, obesity, and activation of signaling pathways involved in EC. Furthermore, we discuss the pharmacological management of EC associated with DM. Early treatment with metformin is expected to be an effective adjuvant alternative for EC in the future. This knowledge is important for further opening up preventive and therapeutic strategies for EC by targeting glucose metabolism.

Fertility-Sparing Treatment for Endometrial Cancer or Atypical Endometrial Hyperplasia Patients With Obesity

Objective

To evaluate the efficacy and prognosis of fertility-sparing treatment on endometrial cancer (EC) and atypical endometrial hyperplasia (AEH) patients with BMI ≥ 30 kg/m2.

Methods

A total of 102 EC or AEH patients with obesity who received fertility-preserving therapy in the Department of Obstetrics and Gynecology, Peking Union Medical College Hospital were included in our study. All patients were followed up regularly. Clinical characteristics, treatment outcomes, adverse events, and reproductive outcomes were collected and analyzed.

Results

A total of 88 (86.3%) patients achieved complete response (CR), 92.5% in AEH and 82.3% in EC, with 6 months (3–12 months) median CR time. High remission rates were found in patients who received gonadotropin-releasing hormone agonist (GnRHa)-based regimen, were younger than 35 years old, and lost more than 10% of their weight. Fifteen (17.0%) women had developed recurrence with a median recurrence time of 26 (8–52) months. Patients who received GnRHa regimen, lost more than 10% weight, received maintenance therapy, or conceived during the follow-up period had a low probability of recurrence. Of the patients with CR, 57 women attempted to get pregnant and 16 (28.1%) patients became pregnant, 7 (12.3%) of them successfully delivered and 4 (7.0%) were in pregnancy, while 5 (8.8%) of them miscarried.

Conclusion

For obese patients with EC and AEH, fertility-preserving treatment can still achieve a promising response. Weight loss of more than 10% has a positive influence on response, recurrence, as well as pregnancy rates. GnRHa could be an option for obese women due to less effect on weight gain compared to progestin therapy.

Management of Recurrent Endometrial Cancer or Atypical Endometrial Hyperplasia Patients After Primary Fertility-Sparing Therapy

Objective

To evaluate the efficacy and prognosis of fertility-sparing re-treatment on patients with recurrent endometrial cancer (EC) and atypical endometrial hyperplasia (AEH) who wish to preserve their uterus after complete remission (CR) for primary conservative therapy.

Methods

We performed a retrospective study on recurrent EC or AEH patients who received fertility-sparing re-treatment after achieving CR. Data regarding clinicopathological factors, adverse events, treatment efficacy, tumor prognosis, and reproductive outcome were analyzed.

Results

Of the 98 recurrent patients with a median disease-free interval period of 19 (3–96) months, 18 patients decided to receive hysterectomy directly, and 80 patients received fertility-preserving re-treatment. Seventy-one (88.6%) cases achieved CR, 96.0% in AEH and 75.8% in EC patients, with the 6 (3–16) months’ median CR time. Seven (8.8%) patients failed to achieve CR and then underwent the hysterectomy: one partial response (PR), four stable disease (SD), and two progressive disease (PD). Forty-nine women attempted to get pregnant after CR, 13 (26.5%) became pregnant, seven (14.3%) successfully delivered, and six (12.2%) miscarried. During the follow-up period, 22 (31.0%) women had developed a second relapse with the median recurrence time of 12 (4–90) months, and 10 patients decided to receive the third round of fertility-sparing treatment. Seven (70.0%) patients, 33.3% in EC and 85.7% in AEH, achieved CR again. Hysterectomy was performed in two (20.0%) patients due to SD. After the third-round treatment, six women had the desire to conceive but no one became pregnant successfully.

Conclusion

For patients with recurrent EC and AEH after primary conservative treatment, fertility-preserving re-treatment can still achieve a promising response, and patients have possibilities of completing childbirth.

Fertility-preserving treatment outcome in endometrial cancer or atypical hyperplasia patients with polycystic ovary syndrome

Objective

This study aimed to investigate the impact of polycystic ovary syndrome (PCOS) on fertility-sparing treatment in young patients with atypical endometrial hyperplasia (AEH) or endometrioid endometrial cancer (EEC).

Methods

A total of 285 patients with EEC (n=76, FIGO stage IA, without myometrium invasion) or AEH (n=209) who received progestin-based fertility-sparing treatment were evaluated retrospectively. Among the 285 patients, 103 (36.1%), including 70 AEH cases and 33 EEC cases, were diagnosed with PCOS. General characteristics, cumulative 16- and 32-week complete response (CR) rate, pregnancy outcome and recurrence were compared between patients with or without PCOS.

Results

The cumulative 16-week CR rate was lower in the PCOS group than in the non-PCOS group (18.4% vs. 33.8%, p=0.006). Patients with PCOS took longer treatment duration to achieve CR (7.0 months vs. 5.4 months, p=0.006) and shorter time to relapse after CR (9.6 months vs. 17.6 months, p=0.040) compared with non-PCOS group. After adjusting for patient age, body mass index, PCOS, homeostasis model assessment-insulin resistance index, and serum testosterone levels, we found that body mass index ≥25 kg/m² (HR=0.583; 95% CI=0.365–0.932; p=0.024) and PCOS (HR=0.545; 95% CI=0.324–0.917; p=0.022) were significantly correlated with lower 16-week CR rate.

Conclusion

PCOS was associated with lower 16-week CR rate, longer treatment duration and shorter recurrence interval in patients with AEH or EEC receiving fertility-preserving treatment.

Breast cancer risk in patients with polycystic ovary syndrome: a Mendelian randomization analysis

PURPOSE

The association between polycystic ovary syndrome (PCOS) and breast cancer remains inconclusive. Conventional observational studies are susceptible to inverse causality and potential confounders. With a Mendelian randomization (MR) approach, we aimed to investigate the causal relationship between genetically predicted PCOS and breast cancer risk.

METHODS

Our study included 11 PCOS-associated single nucleotide polymorphisms as instrumental variables identified by the latest genome-wide association study. Individual-level genetic summary data of participants were obtained from the Breast Cancer Association Consortium, with a total of 122,977 cases and 105,974 controls. The inverse-variance weighted method was applied to estimate the causality between genetically predicted PCOS and breast cancer risk. To further evaluate the pleiotropy, the weighted median and MR-Egger regression methods were implemented as well.

RESULTS

Our study demonstrated that genetically predicted PCOS was causally associated with an increased risk of overall breast cancer (odds ratio (OR) = 1.07; 95% confidence interval (CI) 1.02-1.12, p = 0.005). The subgroup analyses according to immunohistochemical type further illustrated that genetically predicted PCOS was associated with an increased risk of estrogen receptor (ER)-positive breast cancer (OR = 1.09; 95% CI 1.03-1.15, p = 0.002), while no causality was observed for ER-negative breast cancer (OR = 1.02; 95% CI 0.96-1.09, p = 0.463). In addition, no pleiotropy was found in our study.

CONCLUSIONS

Our findings indicated that PCOS was likely to be a causal factor in the development of ER-positive breast cancer, providing a better understanding for the etiology of breast cancer and the prevention of breast cancer.

Insulin Resistance and Endometrial Cancer: Emerging Role for microRNA

Endometrial cancer (EC) remains one of the most common cancers of the female reproductive system. Epidemiological and clinical data implicate insulin resistance (IR) and its accompanying hyperinsulinemia as key factors in the development of EC. MicroRNAs (miRNAs) are short molecules of non-coding endogenous RNA that function as post-transcriptional regulators. Accumulating evidence has shown that the miRNA expression pattern is also likely to be associated with EC risk factors. The aim of this work was the verification of the relationships between IR, EC, and miRNA, and, as based on the literature data, elucidation of miRNA's potential utility for EC prevention in IR patients. The pathways affected in IR relate to the insulin receptors, insulin-like growth factors and their receptors, insulin-like growth factor binding proteins, sex hormone-binding globulin, and estrogens. Herein, we present and discuss arguments for miRNAs as a plausible molecular link between IR and EC development. Specifically, our careful literature search indicated that dysregulation of at least 13 miRNAs has been ascribed to both conditions. We conclude that there is a reasonable possibility for miRNAs to become a predictive factor of future EC in IR patients.

Lipidomic Biomarkers in Polycystic Ovary Syndrome and Endometrial Cancer

Women with polycystic ovary syndrome (PCOS) are more likely to develop endometrial cancer (EC). The molecular mechanisms which increase the risk of EC in PCOS are unclear. Derangements in lipid metabolism are associated with EC, but there have been no studies, investigating if this might increase the risk of EC in PCOS. This was a cross-sectional study of 102 women in three groups of 34 (PCOS, EC and controls) at Nottingham University Hospital, UK. All participants had clinical assessments, followed by obtaining plasma and endometrial tissue samples. Lipidomic analyses were performed using liquid chromatography (LC) coupled with high resolution mass spectrometry (HRMS) and the obtained lipid datasets were screened using standard software and databases. Using multivariate data analysis, there were no common markers found for EC and PCOS. However, on univariate analyses, both PCOS and EC endometrial tissue samples showed a significant decrease in monoacylglycerol 24:0 and capric acid compared to controls. Further studies are required to validate these findings and investigate the potential role of monoacylglycerol 24:0 and capric acid in the link between PCOS with EC.

High level of visfatin and the activation of Akt and ERK1/2 signaling pathways are associated with endometrium malignant transformation in polycystic ovary syndrome

This study aimed to assess the clinicopathological significance of serum levels and endometrium tissue expression of visfatin in polycystic ovary syndrome (PCOS) patients. A total of 80 PCOS patients and 80 matching controls were included in this study. We analyzed the relationship between the expression of visfatin in endometrium and clinicopathological characteristics in PCOS patients. The correlation between the expression of visfatin and p-Akt, Akt, p-ERK1/2, and ERK1/2 in PCOS tissues was evaluated as well. Visfatin expression in PCOS endometrial tissues were significantly higher than those in controls (p = .001). The expression of phosphorylation of Akt and ERK1/2 were significantly higher in PCOS endometrium tissues compared to controls (p < .05). Moreover, a high expression of tissue visfatin in PCOS tissues was positively correlated with the expression of p-Akt (p = .015), and p-ERK1/2 (p = .013). Western blotting revealed that protein expression of visfatin in PCOS patients with endometrial hyperplasia and cancer was higher than that in patients with normal endometrium tissues, and the difference was statistically significant (p = .027). The expression of p-Akt (p = .018) and p-ERK1/2 (p = .035) in PCOS patients with endometrial hyperplasia and cancer was significantly higher than that in patients with normal endometrium tissues. Visfatin may be a potential biomarker for endometrial malignant transformation in PCOS patients.

Increased cancer risk in polycystic ovary syndrome: An (un)sympathetic connection?

Women with polycystic ovary syndrome (PCOS) have been shown to have a higher incidence of cancer. It is suggested that several factors, including hyperinsulinemia, dyslipidemia, raised estrogen levels, chronic inflammation, and reduced apoptosis are responsible for this association. However, in this paper we propose the hypothesis that increased sympathetic activity may represent an important factor that interconnects PCOS and cancer. This hypothesis is based on two facts: a) in women with PCOS is found sympathetic hyperactivity and b) recent data showing a stimulatory effect of the sympathetic system on cancer initiation, progression, and development of metastases. If our hypothesis is correct, then new preventive approaches might be used to reduce cancer risk in women with PCOS.

CP‑31398 attenuates endometrial cancer cell invasion, metastasis and resistance to apoptosis by downregulating MDM2 expression

Endometrial cancer (EC) is one of the most common malignancies of the female reproductive system, and metastasis is a major cause of mortality. In this study, we aimed to explore the role of CP-31398 in the migration, invasion and apoptosis of EC cells by its regulation of the expression of the murine double minute 2 (MDM2) gene. For this purpose, EC tissues and adjacent normal tissues were collected, and the positive expression rate of MDM2 in these tissues was assessed. Subsequently, the cellular 50% inhibitory concentration (IC50) of CP-31398 was measured. The EC RL95-2 and KLE cell lines had a higher MDM2 expression and were thus selected for use in subsequent experiments. The EC cells were then treated with CP-31398 (2 µg/ml), and were transfected with siRNA against MDM2 or an MDM2 overexpression plasmid in order to examine the effects of CP-31398 and MDM2 on EC cell activities. The expression of p53, p21, Bad, Bax, B-cell lymphoma-2 (Bcl-2), cytochrome c (Cyt-c), caspase-3, Cox-2, matrix metalloproteinase (MMP)-2 and MMP-9 was measured to further confirm the effects of CP-31398 on cell migration, invasion and apoptosis. Our results indicated that MDM2 was highly expressed in EC tissues. Notably, EC cell viability decreased with the increasing concentrations of CP-31398. The EC cells treated with CP-31398 or siRNA against MDM2 exhibited an increased apoptosis and a suppressed migration and invasion, corresponding to an increased expression of p53, p21, Bad, Bax, Cyt-c and caspase-3, as well as to a decreased expression of Bcl-2, Cox-2, MMP-2 and MMP-9. Moreover, treatment with CP-31398 and siRNA against MDM2 further enhanced these effects. Taken together, the findings of this study indicate that the CP-31398-mediated downregulation of MDM2 may suppress EC progression via its inhibitory role in EC cell migration, invasion and resistance to apoptosis. Therefore, treatment with CP-31398 may prove to be possible therapeutic strategy for EC.

Expression of NAD(P)H quinone dehydrogenase 1 (NQO1) is increased in the endometrium of women with endometrial cancer and women with polycystic ovary syndrome

OBJECTIVE

Women with a prior history of polycystic ovary syndrome (PCOS) have an increased risk of endometrial cancer (EC).

AIM

To investigate whether the endometrium of women with PCOS possesses gene expression changes similar to those found in EC.

DESIGN AND METHODS

Patients with EC, PCOS and control women unaffected by either PCOS or EC were recruited into a cross-sectional study at the Nottingham University Hospital, UK. For RNA sequencing, representative individual endometrial biopsies were obtained from women with EC, PCOS and a woman unaffected by PCOS or EC. Expression of a subset of differentially expressed genes identified by RNA sequencing, including NAD(P)H quinone dehydrogenase 1 (NQO1), was validated by quantitative reverse transcriptase PCR validation (n = 76) and in the cancer genome atlas UCEC (uterine corpus endometrioid carcinoma) RNA sequencing data set (n = 381). The expression of NQO1 was validated by immunohistochemistry in EC samples from a separate cohort (n = 91) comprised of consecutive patients who underwent hysterectomy at St Mary's Hospital, Manchester, between 2011 and 2013. A further 6 postmenopausal women with histologically normal endometrium who underwent hysterectomy for genital prolapse were also included. Informed consent and local ethics approval were obtained for the study.

RESULTS

We show for the first that NQO1 expression is significantly increased in the endometrium of women with PCOS and EC. Immunohistochemistry confirms significantly increased NQO1 protein expression in EC relative to nonmalignant endometrial tissue (P < .0001).

CONCLUSIONS

The results obtained here support a previously unrecognized molecular link between PCOS and EC involving NQO1.

Reproductive factors and incidence of endometrial cancer in U.S. black women

PURPOSE

Previous studies have shown that reproductive history is a strong determinant of endometrial cancer risk among white women. Less is known about how reproductive history affects endometrial cancer risk among black women, whose incidence and mortality differ from white women. We investigated the associations of age at menarche, parity, timing of births, and menopausal age with endometrial cancer in the Black Women's Health Study, a prospective cohort study.

METHODS

Every 2 years from 1995 to 2013, 47,555 participants with intact uteri at baseline in 1995 completed questionnaires on reproductive and medical history, and lifestyle factors. Self-reported cases of endometrial cancer were confirmed by medical record, cancer registry, or death certificate when available. Cox proportional hazards regression was used to estimate multivariable incidence rate ratios (IRR) and 95% confidence intervals (CI).

RESULTS

During 689,501 person-years of follow-up, we identified 300 incident cases of endometrial cancer. The strongest associations with endometrial cancer were found for early age at menarche (<11 vs. 12-13 years: IRR 1.82, 95% CI 1.31, 2.52), and later age at first birth (≥30 vs. <20 years: IRR 0.26, 95% CI 0.13, 0.50). Parous women were less likely than nulliparous women to develop endometrial cancer (IRR 0.77, 95% CI 0.57, 1.05), but there was little evidence of a dose-response relationship for number of births.

CONCLUSION

Associations between reproductive factors and endometrial cancer among black women were generally consistent with those in studies of white women.

Sterol regulatory element binding protein-1 (SREBP1) gene expression is similarly increased in polycystic ovary syndrome and endometrial cancer

INTRODUCTION

Women with polycystic ovary syndrome have a three-fold higher risk of endometrial cancer. Insulin resistance and hyperlipidemia may be pertinent factors in the pathogenesis of both conditions. The aim of this study was to investigate endometrial sterol regulatory element binding protein-1 gene expression in polycystic ovary syndrome and endometrial cancer endometrium, and to correlate endometrial sterol regulatory element binding protein-1 gene expression with serum lipid profiles.

MATERIAL AND METHODS

A cross-sectional study was performed at Nottingham University Hospital, UK. A total of 102 women (polycystic ovary syndrome, endometrial cancer and controls; 34 participants in each group) were recruited. Clinical and biochemical assessments were performed before endometrial biopsies were obtained from all participants. Taqman real-time polymerase chain reaction for endometrial sterol regulatory element binding protein-1 gene and its systemic protein expression were analyzed.

RESULTS

The body mass indices of women with polycystic ovary syndrome (29.28 ± 2.91 kg/m² ) and controls (28.58 ± 2.62 kg/m² ) were not significantly different. Women with endometrial cancer had a higher mean body mass index (32.22 ± 5.70 kg/m² ). Sterol regulatory element binding protein-1 gene expression was significantly increased in polycystic ovary syndrome and endometrial cancer endometrium compared with controls (p < 0.0001). Sterol regulatory element binding protein-1 gene expression was positively correlated with body mass index (r = 0.017, p = 0.921) and waist-hip ratio (r = 0.023, p = 0.544) in polycystic ovary syndrome, but this was not statistically significant. Similarly, statistically insignificant positive correlations were found between endometrial sterol regulatory element binding protein-1 gene expression and body mass index in endometrial cancer (r = 0.643, p = 0.06) and waist-hip ratio (r = 0.096, p = 0.073). Sterol regulatory element binding protein-1 gene expression was significantly positively correlated with triglyceride in both polycystic ovary syndrome and endometrial cancer (p = 0.028 and p = 0.027, respectively). Quantitative serum sterol regulatory element binding protein-1 gene correlated with endometrial gene expression (p < 0.05).

CONCLUSIONS

Sterol regulatory element binding protein-1 gene expression is significantly increased in the endometrium of women with polycystic ovary syndrome and women with endometrial cancer compared with controls and positively correlates with serum triglyceride in both polycystic ovary syndrome and endometrial cancer.

Up-regulation of genes involved in the insulin signalling pathway (IGF1, PTEN and IGFBP1) in the endometrium may link polycystic ovarian syndrome and endometrial cancer

BACKGROUND

Endometrial cancer (EC) is the most common gynaecological cancer amongst women in the UK. Although previous studies have found that women with polycystic ovary syndrome (PCOS) have at least a three-fold increase in endometrial cancer (EC) risk compared to women without PCOS, the precise molecular mechanisms which link between PCOS and EC remain unclear. It has been suggested that insulin resistance may contribute to the increased risk of EC in PCOS. The specific expression of genes related to the insulin-signalling pathway including the IGF system in the endometrium of women with PCOS has however never been measured and compared to that in women with EC without PCOS and control women without EC or PCOS. .

OBJECTIVES

To test the hypothesis that insulin signalling plays a key role in the development of EC in women with PCOS by measuring and comparing the expression of three key genes involved in the insulin signalling pathway (IGF1, PTEN and IGFBP1) in endometrial tissue obtained from three groups of women; PCOS without EC, women with EC without PCOS and non-PCOS women without EC (controls). We also aimed to determine the correlation between the gene expressions to various clinical variables among participants.

METHODS

This was a cross-sectional study of 102 women in 3 groups (PCOS, EC and controls) at a University teaching hospital in the United Kingdom. Clinical assessment (blood pressure, body mass index (BMI) and waist-hip-circumference ratio), venepuntures (fasting blood sugar, insulin, lipid profile, hormones) and endometrial tissue biopsies were taken in all participants. Endometrial tissue RNA extraction was performed before real time polymerase-chain-reaction for the genes of interest (IGF1, IGFBP1 and PTEN) was carried out. To compare the baseline characteristics of the study population, One-Way-ANOVA test or the Independent t-test was used. For variables that were not normally distributed, the Spearman correlation test was used to calculate the r value. A "p" value of <0.05 was considered statistically significant.

RESULTS

IGF1, IGFBP1 and PTEN gene expression were significantly up-regulated in the endometrium of PCOS and EC women compared to controls. However there was no significant difference in the expression of these genes in PCOS compared to EC endometrium. The BMI of women with PCOS and controls, were not significantly different (29.28 (± 2.91) vs 28.58 (± 2.62) kg/m(2)) respectively, women with EC however had a higher mean BMI (32.22 (± 5.70) kg/m(2)). PCOS women were younger (31.8 (± 5.97) years) than women with EC (63.44 (± 10.07) years) and controls (43.68 (± 13.12) years). The changes in gene expression were independent of BMI, waist hip ratio, estradiol and androgen levels. Protein validation test in the serum samples in the three groups were consistent with the gene findings.

CONCLUSION

Women with PCOS and EC have an increased endometrial expression of genes (IGF1, IGFBP1 and PTEN) involved in the insulin signalling pathway compared with control women. This may explain the increased risk of EC in PCOS women. This study provides a strong basis for clinical trials aiming to prevent EC in women with PCOS by investigating drugs targeting the insulin signalling pathway. This panel of genes may also serve as clinically useful early biomarkers which predict which women with PCOS will go on to develop EC.

Roles of Oxidative Stress in Polycystic Ovary Syndrome and Cancers

Oxidative stress (OS) has received extensive attention in the last two decades, because of the discovery that abnormal oxidation status was related to patients with chronic diseases, such as diabetes, cardiovascular, polycystic ovary syndrome (PCOS), cancer, and neurological diseases. OS is considered as a potential inducing factor in the pathogenesis of PCOS, which is one of the most common complex endocrine disorders and a leading cause of female infertility, affecting 4%–12% of women in the world, as OS has close interactions with PCOS characteristics, just as insulin resistance (IR), hyperandrogenemia, and chronic inflammation. It has also been shown that DNA mutations and alterations induced by OS are involved in cancer pathogenesis, tumor cell survival, proliferation, invasion, angiogenesis, and so on. Furthermore, recent studies show that the females with PCOS are reported to have an increasing risk of cancers. As a result, the more serious OS in PCOS is regarded as an important potential incentive for the increasing risk of cancers, and this study aims to analyze the possibility and potential pathogenic mechanism of the above process, providing insightful thoughts and evidences for preventing cancer potentially caused by PCOS in clinic.

Polycystic ovary syndrome and risk of endometrial cancer: a mini-review

The polycystic ovary syndrome is the most common endocrinological disorder of reproductive age women with a prevalence of 5 to 8 %. The most common diagnostic criteria used for polycystic ovary syndrome are oligo- or an-ovulation, clinical and/ or biochemical signs of hyperandrogenism and polycystic ovaries. Hyperandrogenism results in increased estrogen levels and lack of cyclic progesterone due to anovulation and persistent stimulation of the endometrium may lead to endometrial hyperplasia or adenocarcinoma development. In this mini review, we aimed to evaluate the possible relationship between polycystic ovary syndrome and endometrial cancer.

The effect of Metformin on endometrial tumor-regulatory genes and systemic metabolic parameters in polycystic ovarian syndrome--a proof-of-concept study

The aim of this proof-of-concept study was to determine the effects of three-month Metformin therapy on the expression of tumor-regulatory genes (p53, cyclin D2 and BCL-2) in the endometrium of women with polycystic ovary syndrome (PCOS). A total of 40 women, aged between 21 and 45 years with PCOS (Rotterdam criteria) were recruited. The participants were assessed at pre- and 3-month-post-Metformin therapy for the menstrual regularities, weight reduction, Ferriman Galway scores, fasting blood glucose (FBG), total cholesterol, LDL, HDL and p53, BCL-2 and cyclin D2 gene expression. Five participants conceived spontaneously after the initial recruitment. Majority (68%) resumed regular menstrual cycles after Metformin. There were significant reduction in BMI (p = 0.001), weight (p = 0.001) and Ferriman Galway scores (p = 0.001). A significant improvement was seen in mean FBG (p = 0.002), total cholesterol (p = 0.001), LDL (p = 0.003) and HDL cholesterol levels (p = 0.015). Tumor suppressor gene (p53) was significantly up-regulated after Metformin (10 out of 14 women), with p value 0.016. BCL-2 and cyclin D2 (oncogenes) were slightly up-regulated without significant difference (p = 0.119 and 0.155, respectively). In conclusion, Metformin therapy improved clinical and metabolic parameters in women with PCOS and up-regulated p53 tumor suppressor gene significantly. Further studies are however required to independently validate our findings.

Impact of obesity on the results of fertility-sparing management for atypical hyperplasia and grade 1 endometrial cancer

OBJECTIVES

The aim of the present study was to evaluate the impact of obesity on reproductive and oncologic outcomes on the success of fertility-sparing management.

METHODS

This retrospective multicenter cohort study included women treated conservatively for atypical hyperplasia (AH) and endometrial cancer (EC) to preserve fertility. Five inclusion criteria were defined: (i) the presence of AH or grade 1 EC confirmed by two pathologists; (ii) adequate radiological examination before conservative management; (iii) available body mass index (BMI) at the beginning of treatment; and (iv) a minimum follow-up time of six months.

RESULTS

Forty patients fulfilled the inclusion criteria (17 had EC, and 23 had AH), mean age and BMI were 33 years and 29kg/m(2) respectively. Among the 15 obese patients, after medical treatment, 10 patients responded (67%) and three relapsed, whereas in the 25 non-obese patients, 19 responded (76%) and three relapsed (p=0.72). The overall pregnancy rate and follow-up time were 35% and 35 months respectively. Among the 15 obese patients, after medical treatment, two patients became pregnant, whereas in the 25 non-obese patients, 12 became pregnant (p=0.04).

CONCLUSION

Despite similar response and recurrence rates, our results suggest that fertility-sparing management for AH and EC is associated with a lower probability of pregnancy in obese patients.