Polycystic ovary syndrome and risk of endometrial, ovarian, and breast cancer: a systematic review

The polycystic ovary syndrome and gynecological cancer risk

This review updates the knowledge regarding the association between the polycystic ovary syndrome (PCOS) and the risk of gynecological cancer. We performed a literature review of clinical and epidemiological studies concerning PCOS and the risk of breast, endometrial and ovarian cancer after selecting information by quality of scientific methodology. It was found that evidence does not support a link between PCOS and breast cancer risk. There is an increased risk of endometrial cancer, while data concerning ovarian cancer are contradictory. Regarding PCOS and its association to cervical, fallopian tube, and vulvar cancer, the quality of evidence is heterogeneous. In conclusion, women with PCOS should be screened for endometrial cancer and more research is warranted to determine in this population the true risk of developing other gynecological cancers such as breast and ovarian.

Association between genetically predicted polycystic ovary syndrome and ovarian cancer: a Mendelian randomization study

BACKGROUND

Polycystic ovary syndrome (PCOS) is a complex endocrine disorder with an estimated prevalence of 4-21% in reproductive aged women. Recently, the Ovarian Cancer Association Consortium (OCAC) reported a decreased risk of invasive ovarian cancer among women with self-reported PCOS. However, given the limitations of self-reported PCOS, the validity of these observed associations remains uncertain. Therefore, we sought to use Mendelian randomization with genetic markers as a proxy for PCOS, to examine the association between PCOS and ovarian cancer.

METHODS

Utilizing 14 single nucleotide polymorphisms (SNPs) previously associated with PCOS we assessed the association between genetically predicted PCOS and ovarian cancer risk, overall and by histotype, using summary statistics from a previously conducted genome-wide association study (GWAS) of ovarian cancer among European ancestry women within the OCAC (22 406 with invasive disease, 3103 with borderline disease and 40 941 controls).

RESULTS

An inverse association was observed between genetically predicted PCOS and invasive ovarian cancer risk: odds ratio (OR)=0.92 [95% confidence interval (CI)=0.85-0.99; P = 0.03]. When results were examined by histotype, the strongest inverse association was observed between genetically predicted PCOS and endometrioid tumors (OR = 0.77; 95% CI = 0.65-0.92; P = 0.003). Adjustment for individual-level body mass index, oral contraceptive use and parity did not materially change the associations.

CONCLUSION

Our study provides evidence for a relationship between PCOS and reduced ovarian cancer risk, overall and among specific histotypes of invasive ovarian cancer. These results lend support to our previous observational study results. Future studies are needed to understand mechanisms underlying this association.

Environmental toxin exposure in polycystic ovary syndrome women and possible ovarian neoplastic repercussion

Purpose: Over the last two decades, increasing attention has been paid to environmental toxins and their effects on the female reproductive system. Endocrine disrupting chemicals (EDCs) are exogenous substances or mixtures that can mimic the action of steroid hormones and interfere with their metabolism. Advanced glycation end products (AGEs) are proinflammatory molecules that can interact with cell surface receptors and mediate the triggering of proinflammatory pathways and oxidative stress. The purpose of this review is to explore the effects of environmental toxin exposure in the pathogenesis of both polycystic ovary syndrome (PCOS) and OC (ovarian cancer), considered separately, and also to evaluate possible neoplastic ovarian repercussion after exposure in patients diagnosed with PCOS.Materials and methods: We searched PubMed for articles published in the English language with the use of the following MeSH search terms: "polycystic ovary syndrome" and "ovarian cancer" combined with "endocrine disruptors". Titles and abstracts were examined and full articles that met the selection criteria were retrieved. A manual search of review articles and cross-references completed the search.Results: Extensive data from different studies collected in recent years concerning the effects of EDC/AGE exposure have confirmed their role in the pathophysiology of both PCOS and OC. They favor PCOS/OC development through different mechanisms that finally lead to hormonal and metabolic disruption and epigenetic modifications.Conclusions: Environmental toxin exposure in PCOS women could favor neoplastic transformation by exacerbating and potentiating some PCOS features. Further research, although difficult, is needed in order to prevent further diffusion of these substances in the environment, or at least to provide adequate information to the population considered at risk.

Effects of Chromium and Carnitine Co-supplementation on Body Weight and Metabolic Profiles in Overweight and Obese Women with Polycystic Ovary Syndrome: a Randomized, Double-Blind, Placebo-Controlled Trial

The primary aim of our study was to determine the influence of taking chromium plus carnitine on insulin resistance, with a secondary objective of evaluating the influences on lipid profiles and weight loss in overweight subjects with polycystic ovary syndrome (PCOS). In a 12-week randomized, double-blind, placebo-controlled clinical trial, 54 overweight women were randomly assigned to receive either supplements (200 μg/day chromium picolinate plus 1000 mg/day carnitine) or placebo (27/each group). Chromium and carnitine co-supplementation decreased weight (- 3.6 ± 1.8 vs. - 1.0 ± 0.7 kg, P < 0.001), BMI (- 1.3 ± 0.7 vs. - 0.3 ± 0.3 kg/m², P < 0.001), fasting plasma glucose (FPG) (- 5.1 ± 6.0 vs. - 1.1 ± 4.9 mg/dL, P = 0.01), insulin (- 2.0 ± 1.4 vs. - 0.2 ± 1.2 μIU/mL, P < 0.001), insulin resistance (- 0.5 ± 0.4 vs. - 0.04 ± 0.3, P < 0.001), triglycerides (- 18.0 ± 25.2 vs. + 5.5 ± 14.4 mg/dL, P < 0.001), total (- 17.0 ± 20.3 vs. + 3.6 ± 12.0 mg/dL, P < 0.001), and LDL cholesterol (- 13.3 ± 19.2 vs. + 1.4 ± 13.3 mg/dL, P = 0.002), and elevated insulin sensitivity (+ 0.007 ± 0.005 vs. + 0.002 ± 0.005, P < 0.001). In addition, co-supplementation upregulated peroxisome proliferator-activated receptor gamma (P = 0.02) and low-density lipoprotein receptor expression (P = 0.02). Overall, chromium and carnitine co-supplementation for 12 weeks to overweight women with PCOS had beneficial effects on body weight, glycemic control, lipid profiles except HDL cholesterol levels, and gene expression of PPAR-γ and LDLR. Clinical trial registration number: http://www.irct.ir: IRCT20170513033941N38.

Prenatally androgenized female rats develop uterine hyperplasia when adult

Prenatal hyperandrogenization (PH) is hypothesized as one of the main factors contributing to the development of polycystic ovary syndrome (PCOS). In this study, we aimed to investigate the impact of prenatal exposure to androgen excess on the uterus when animals reach their adulthood. We found that PH altered the morphology of the uteri that show a hyperplastic morphology with increased total uterine thickness as well as luminal epithelium thickness, with both enhanced and altered distribution of glands as compared with controls. Morphological alterations were associated with an unbalanced homeostasis as assessed by the expression of regulators of cell cycle progression and cell death dynamics. PH also causes disturbances in the cell cycle of the uterine tissue and dysregulates cell death and survival pathways leading to the development of uterine hyperplasia. These findings suggest that PH may have a deleterious effect on the uterus.

Risk of postmenopausal hormone therapy and patient history factors for the survival rate in women with endometrial carcinoma

PURPOSE

Postmenopausal hormone therapy (HT) is known to affect the development of hormone-dependent endometrial carcinoma (type I EC). Several studies on breast and ovarian carcinoma have shown that HT influences the molecular profile and prognostic behavior of these tumors. This study aimed to investigate the influence of prior HT and other risk factors on the prognosis in a cohort of patients with invasive endometrial carcinoma (EC).

METHODS

Among 525 patients diagnosed with EC between 1987 and 2010, 426 postmenopausal patients were identified. Information regarding HT was available in 287 of these patients, 78 of whom had a history of HT and 209 of whom did not. Both overall survival (OS) and progression-free survival (PFS) were analyzed. In addition to OS and PFS, risk factors such as age at diagnosis, postmenopausal HT, body mass index (BMI), diabetes mellitus, tumor stage, EC type (I or II), and recurrences were analyzed.

RESULTS

Relative to HT alone, women with EC and a history of HT had a longer survival than those with no HT. However, the Cox proportional hazards model showed that it was not HT itself, but rather other characteristics in the HT group that were causally associated with longer survival.

CONCLUSIONS

Age (the older, the worse) and tumor stage (the higher, the worse) were significant influences on overall survival. Patients with HT also had lower BMIs, less diabetes, more type I EC, and fewer recurrences in comparison with the non-HT group. With regard to the PFS, it made no difference whether the patient was receiving HT.

Graph cluster approach in identifying novel proteins and significant pathways involved in polycystic ovary syndrome

RESEARCH QUESTION

Polycystic ovary syndrome (PCOS) is a complex endocrine disorder with diverse clinical implications, such as infertility, metabolic disorders, cardiovascular diseases and psychological problems among others. The heterogeneity of conditions found in PCOS contribute to its various phenotypes, leading to difficulties in identifying proteins involved in this abnormality. Several studies, however, have shown the feasibility in identifying molecular evidence underlying other diseases using graph cluster analysis. Therefore, is it possible to identify proteins and pathways related to PCOS using the same approach?

METHODS

Known PCOS-related proteins (PCOSrp) from PCOSBase and DisGeNET were integrated with protein-protein interactions (PPI) information from Human Integrated Protein-Protein Interaction reference to construct a PCOS PPI network. The network was clustered with DPClusO algorithm to generate clusters, which were evaluated using Fisher's exact test. Pathway enrichment analysis using gProfileR was conducted to identify significant pathways.

RESULTS

The statistical significance of the identified clusters has successfully predicted 138 novel PCOSrp with 61.5% reliability and, based on Cronbach's alpha, this prediction is acceptable. Androgen signalling pathway and leptin signalling pathway were among the significant PCOS-related pathways corroborating the information obtained from the clinical observation, where androgen signalling pathway is responsible in producing male hormones in women with PCOS, whereas leptin signalling pathway is involved in insulin sensitivity.

CONCLUSIONS

These results show that graph cluster analysis can provide additional insight into the pathobiology of PCOS, as the pathways identified as statistically significant correspond to earlier biological studies. Therefore, integrative analysis can reveal unknown mechanisms, which may enable the development of accurate diagnosis and effective treatment in PCOS.

Why does Polycystic Ovary Syndrome (PCOS) Need Long-term Management?

BACKGROUND

Polycystic ovary syndrome (PCOS) is a frequent female reproductive endocrine disease. It has been associated with a number of severe reproductive and metabolic abnormalities. However, there are still open questions especially regarding the best long-term management.

METHODS

We summarized the literature focused on the symptoms and negative long-term consequences of untreated PCOS and the existing options for the treatment. We reviewed the Pubmed and China National Knowledge Infrastructure databases and the relevant literature for the last 20 years. Included in this review also are new results of own (published) research and own experience from treating daily more than 100 PCOS patients.

RESULTS

Obesity is one of the most common findings. It can cause abnormal ovulations which can lead to infertility. Important long-term consequences can be adverse pregnancy outcomes. There is an agreement that the risk of endometrial cancer can be increased. Insulin resistance, important within the pathophysiology of PCOS, predisposes patients to metabolic dysfunction and increased risk of type 2 diabetes mellitus. Lifestyle modifications including dietary changes, exercise and weight loss are first-line interventions for many patients. Well known drug treatments such as metformin, oral contraceptives, etc. should be selected according to the individual situation and patients' needs. Regarding newer methods in the long-term management of PCOS, we found that orlistat may help to achieve weight loss and to improve lipid and glucose metabolism.

CONCLUSION

In addition to pharmacological interventions, long-term standardized individualized management of PCOS patients is needed to achieve fertility and to reduce the risk of metabolic related diseases.

Controversial association between polycystic ovary syndrome and breast cancer

Polycystic ovary syndrome (PCOS) risk factors overlap with breast cancer, and the hormonal profile may be implicated in breast cancer pathogenesis. This study aims to report a literature review considering epidemiological and molecular mechanisms that correlate PCOS and breast cancer, as well as the influence of PCOS treatment on the incidence of breast cancer. Epidemiological studies failed to adjust potential variables that affect the risk and have thus provided inconclusive results. Molecular effects of androgenic pathways in breast cancer have been studied and androgens seem to have an inhibitory effect on mammary epithelial proliferation. However, increased bioavailable androgens were associated with recurrence of breast cancer due to conversion to oestrogens. Sex hormone-binding globulin has a role in hormone-dependent cancers and can be considered a marker for PCOS; a gene profile has already been linked to breast cancer risk in these patients. PCOS medical treatment is a promising tool for stratifying breast cancer risk due to the metabolic influence and hormonal environment. Clinical reports are inconsistent, emphasizing the need for further studies with a prospective design. In the future, the role of pharmacological interventions in PCOS will increase knowledge and awareness of breast cancer pathogenesis and will help to refine breast cancer risk stratification.

Analysis of postoperative radiotherapy effects within risk groups in patients with FIGO I, II, and III endometrial cancer

INTRODUCTION

To define indications for adjuvant radiotherapy in patients with endometrial cancer, the risk groups have been established according to clinical and pathological prognostic factors. The purpose was to determine precise criteria for adjuvant radiotherapy and identify patients with increased risk for disease relapse who may benefit from postoperative radiotherapy, with an acceptable level of toxicity.

MATERIALS AND METHODS

A retrospective study was conducted at the Department of Oncology and Radiology, Kragujevac, during a 5-year period. A group of 80 patients with endometrial cancer treated with adjuvant radiotherapy were included in the study. Patients were divided into four risk groups according to ESMO-ESGO-ESTRO Consensus Conference classification. The Kaplan-Meier method was used for overall and progression-free survival. A statistical analysis was performed using SPSS 20.0 statistical software.

RESULTS

The 5-year survival rate was 80%, and 66.3% patients were progression-free during this period. Fatal outcome occurred in 20% of patients. The results showed survival was shortest in patients from the high-risk group. Factors that had impact on the 5-year survival were comorbidities, FIGO stage, postoperative radiotherapy, organ site of late toxicity, and localization of metastases. The analysis of postoperative radiotherapy effects showed that 72.5% of patients had no complications. The most common symptoms of late irradiation toxicity arose from the gastrointestinal tract. Toxicity was usually moderate.

CONCLUSIONS

Adjuvant radiotherapy can potentially prolong survival and prevent recurrence, with acceptable level of toxicity, to preserve patient's quality of life. Patient classification into appropriate risk groups allows for adjuvant treatment individualization.

Assisted reproductive technology treatment and risk of ovarian cancer—a nationwide population-based cohort study

STUDY QUESTION

Does hormone stimulation during assisted reproductive technology (ART) treatment increase the risk of ovarian cancer?

SUMMARY ANSWER

No increased risk of ovarian cancer was found among ART-treated women, with the exception of ART-treated women with endometriosis.

WHAT IS KNOWN ALREADY

Previous studies on the association between ovarian stimulation during ART and ovarian cancer have shown conflicting results. The risk of ovarian cancer varies according to the cause of infertility, and only a few studies on ART treatment and risk of ovarian cancer have had sufficient data to address this issue. Endometriosis has been linked to an increased risk of ovarian cancer.

STUDY DESIGN, SIZE, DURATION

Women undergoing ART treatment during 1994–2015 were registered in the Danish IVF register. Data were linked with data from the Danish Cancer Register and socio-demographic population registers using an individual person identification number assigned to people residing in Denmark.

PARTICIPANTS/MATERIALS, SETTING, METHODS

All women undergoing ART treatment were age-matched with a random sample of the female background population and followed for up to 22 years. After relevant exclusions, the population consisted of 58 472 ART-treated women and 625 330 untreated women, all with no previous malignancies. Ovarian cancer risk was assessed using multivariable cox regression analyses with adjustment for educational level, marital status, parity and treatment year. Results are shown as hazard ratios (HRs) with corresponding CIs.

MAIN RESULTS AND THE ROLE OF CHANCE

In total, 393 (0.06%) women were diagnosed with ovarian cancer during follow-up (mean 9.7 years). Women treated with ART had an increased risk of ovarian cancer (HR 1.20, 95% CI 1.10–1.31), which diminished over time. The increased risk was apparent among women with female factor infertility (HR 1.36, 95% CI 1.25–1.48), whereas no female factor infertility was associated with a lower risk (HR 0.87, 95% CI 0.76–1.00). The risk was increased among women with endometriosis (HR 3.78, 95% CI 2.45–5.84), whereas no increased risk was found among ART-treated women with polycystic ovary syndrome, other female causes of infertility and unexplained infertility.

LIMITATIONS, REASONS FOR CAUTION

The association between ART treatment and ovarian cancer is likely influenced by increased detection due to multiple ultrasound scans during ART treatment.

WIDER IMPLICATIONS OF THE FINDINGS

Undergoing ART treatment without the presence of endometriosis was not associated with an increased risk of ovarian cancer, which is reassuring. Whether ART treatment increases the risk of ovarian cancer among women with endometriosis needs further investigation.

STUDY FUNDING/COMPETING INTEREST(S)

This work was supported by a PhD grant to D.V. from the Faculty of Health and Medical Sciences, University of Copenhagen, Denmark. Funding for establishing the Danish National ART-couple II cohort was achieved from Ebba Rosa Hansen Foundation. The funders had no influence on data collection, analyses or results presented. The authors have no conflicts of interest to declare.

Breast density in polycystic ovarian syndrome patients: A case-control study

Background

Epidemiological studies suggested a positive relationship between breast density and risk of breast cancer. One of the common hormonal disorders in women's reproductive age is polycystic ovarian syndrome (PCOS) and the results from the studies about the risk of breast cancer among PCOS patients are equivocal.

Objective

The objective was to evaluate the breast density in PCOS patients compared with the control group.

Materials and Methods

In this case-control study, the PCOS patients who were older than 40 years and were referred to infertility or gynecology outpatient clinic of Arash women's hospital between 2015 and 2017 were selected as the case group. Control group was selected from healthy women who attended the same hospital and were older than 40 years. By digital mammography, breast density was classified according to the Breast Imaging Reporting and Data System (BIRADS) of the American College of Radiology and it was graded by one expert radiologist.

Results

Final analysis in 68 cases and controls showed statistically significant differences between breast densities in PCOS patients compared to the control (p░=░0.03), and when the analysis was conducted by considering the category of age, the control group who were younger than 45 years had higher breast density compared with PCOS patient. Multivariate logistic regression analyses manifested a statistically significant adverse association between body mass index (OR░=░0.87, 95% CI: 0.79–0.95), vitamin D intake (OR░=░0.35, 95% CI: 0.16–0.81), and breast density.

Conclusion

Our data suggested that the PCOS patients had lower breast density compared with normal population. However, in multivariate analysis, considering other confounders, this association was not confirmed.

Protein-Protein Interaction Network Analysis Reveals Several Diseases Highly Associated with Polycystic Ovarian Syndrome

Based on clinical observations, women with polycystic ovarian syndrome (PCOS) are prone to developing several other diseases, such as metabolic and cardiovascular diseases. However, the molecular association between PCOS and these diseases remains poorly understood. Recent studies showed that the information from protein-protein interaction (PPI) network analysis are useful in understanding the disease association in detail. This study utilized this approach to deepen the knowledge on the association between PCOS and other diseases. A PPI network for PCOS was constructed using PCOS-related proteins (PCOSrp) obtained from PCOSBase. MCODE was used to identify highly connected regions in the PCOS network, known as subnetworks. These subnetworks represent protein families, where their molecular information is used to explain the association between PCOS and other diseases. Fisher's exact test and comorbidity data were used to identify PCOS-disease subnetworks. Pathway enrichment analysis was performed on the PCOS-disease subnetworks to identify significant pathways that are highly involved in the PCOS-disease associations. Migraine, schizophrenia, depressive disorder, obesity, and hypertension, along with twelve other diseases, were identified to be highly associated with PCOS. The identification of significant pathways, such as ribosome biogenesis, antigen processing and presentation, and mitophagy, suggest their involvement in the association between PCOS and migraine, schizophrenia, and hypertension.

Detection of T lymphocyte subsets and related functional molecules in follicular fluid of patients with polycystic ovary syndrome

Immune responses play an important role in the pathogenesis of polycystic ovary syndrome (PCOS). However, the characteristics of T lymphocyte subsets in PCOS remain insufficiently understood. In this study, lymphocytes of follicular fluid (FF) were obtained from oocyte retrieval before in-vitro fertilization (IVF) in infertile women with or without PCOS. The levels of cluster of differentiation 25 (CD25), CD69, programmed death 1 (PD-1), interferon-γ (IFN-γ), interleukin 17A (IL-17A) and IL-10 in T lymphocytes were determined by flow cytometry. Our results showed that the percentage of FF CD8⁺ T cells was significantly decreased in infertile patients with PCOS (P < 0.05). Furthermore, the levels of CD69 and IFN-γ were significantly decreased and the level of PD-1 was increased in both CD4⁺ and CD8⁺ T cells from infertile patients with PCOS (P < 0.05). Moreover, the expression of PD-1 on CD4⁺ or CD8⁺ T cells was positively correlated with the estradiol (E2) levels in the serum and reversely correlated with the expression of IFN-γ in CD4⁺ or CD8⁺ T cells in infertile patients with PCOS. These results suggested that T cell dysfunction may be involved in the pathogenesis of PCOS.

Genetic and epigenetic characteristics in ovarian tissues from polycystic ovary syndrome patients with irregular menstruation resemble those of ovarian cancer

BACKGROUND

Irregular menstruation is clinically associated with an increased risk for ovarian cancer and disease-related mortality. This relationship remains poorly understood, and a mechanism explaining it has yet to be described.

METHODS

Ovarian tissues from women with polycystic ovary syndrome (PCOS) and regular menstruation (n = 10) or irregular menstruation (n = 10) were subjected to DNA methylation sequencing, real-time PCR array, whole-exome sequencing, and bioinformatics analysis.

RESULTS

We demonstrated that ovarian tissue from PCOS patients with irregular menstruation displayed global DNA hypomethylation, as well as hypomethylation at several functionally and oncologically significant regions. Furthermore, we showed that several cancer-related genes were aberrantly expressed in ovarian tissue from patients with irregular menstruation, and that their mRNA and microRNA profiles shared appreciable levels of coincidence with those from ovarian cancer tissue. We identified multiple point mutations in both the BRCA1 and MLH1 genes in patients with irregular menstruation, and predicted the potential pathogenicity of these mutations using bioinformatics analyses.

CONCLUSIONS

Due to the nature of ovarian cancer, it is important to broaden our understanding of the pathogenesis and risk factors of the disease. Herein, we provide the first description of a genetic and epigenetic basis for the clinical relationship between irregular menstruation and an increased risk for ovarian cancer.

The risk of breast and gynecological cancer in women with a diagnosis of infertility: a nationwide population-based study

Some studies have suggested that infertility is a risk factor for endometrial, ovarian and breast cancer. The study aimed to create a comprehensive picture of the association between infertility and the risk of ovarian, endometrial and breast cancer, and whether any association could be explained by ovulatory disturbances, endometriosis or nulliparity. In a population-based cohort of 2,882,847 women, cox regression analysis was used to investigate cancer incidence among infertile women. Overall, infertility was associated with a higher incidence rate of ovarian (adjusted hazard ratio [aHR] 1.53, 95% confidence interval [CI] 1.38-1.71) and endometrial cancer (aHR 1.25, 95% CI 1.11-1.40), but not of breast cancer (aHR 0.96, 95% CI 0.92-1.01). Ovarian cancer incidence was higher in women diagnosed with endometriosis, and in nulliparous women with ovulatory disturbances, compared to women with none of the diagnoses. Endometrial cancer incidence was higher in women with ovulatory disturbances, but not in women with endometriosis. These findings suggest that infertility could have long-term consequences of importance to physicians and public health workers.

Sport, doping and female fertility

This article is a review that addresses the following topics, divided by paragraphs. The first paragraph investigates the effects of physical activity on ovarian function, analyzing in particular the changes concerning the serum concentrations of follicle-stimulating hormone, luteinizing hormone, prolactin, growth hormone, thyroid hormones, leptin, ghrelin, neuropeptide Y. The second paragraph analyzes the effects of doping on the hypothalamic-pituitary-ovarian axis. Finally, the last paragraph analyzes the PCOS category, evaluating the effects of hyperandrogenism in relation to athletic performance.

Association between polycystic ovarian syndrome and endometrial, ovarian, and breast cancer: A population-based cohort study in Taiwan

Polycystic ovary syndrome (PCOS) is a common endocrine disorder among the women of reproductive age. We conducted a nationwide population-based retrospective cohort study to analyze the association between PCOS and the subsequent development of gynecological cancers, namely endometrial, breast, and ovarian cancer.For this population-based cohort study, we used the Taiwan National Health Insurance Research Database, which contains information on approximately 24.7 million insured individuals. The cohort included women who had received a diagnosis of PCOS between 1998 and 2013. An age-matched systematic random-sampling method with a ratio of 1:4 was used for patient selection for the non-PCOS reference cohort. Multivariate Cox proportional hazard regression analysis was used to determine the effects of PCOS on the risks of gynecologic and breast cancer. The data are presented as hazard ratios (HRs) with 95% confidence intervals (CIs).The PCOS cohort consisted of 8155 patients with PCOS, and the comparison cohort consisted of 32,620 matched patients without PCOS. The incidence of endometrial cancer was 226 and 15 per 100,000 person-years in the PCOS and comparison groups, respectively. A statistically significant higher risk of endometrial cancer was found in the PCOS cohort (adjusted HR [aHR] = 17.7, 95% CI = 4.9-64.2) than in the comparison cohort. However, no association was observed between PCOS and ovarian (aHR = 1.64, 95% CI: 0.63-4.27) or breast cancer (aHR = 0.98, 95% CI: 0.58-1.65).The results of this large population-based cohort study supported the premise that women with PCOS might have an increased risk of endometrial cancer, but no association between PCOS and the risks of ovarian and breast cancer was found.

The Role of Inflammation and Inflammatory Mediators in the Development, Progression, Metastasis, and Chemoresistance of Epithelial Ovarian Cancer

Inflammation plays a role in the initiation and development of many types of cancers, including epithelial ovarian cancer (EOC) and high grade serous ovarian cancer (HGSC), a type of EOC. There are connections between EOC and both peritoneal and ovulation-induced inflammation. Additionally, EOCs have an inflammatory component that contributes to their progression. At sites of inflammation, epithelial cells are exposed to increased levels of inflammatory mediators such as reactive oxygen species, cytokines, prostaglandins, and growth factors that contribute to increased cell division, and genetic and epigenetic changes. These exposure-induced changes promote excessive cell proliferation, increased survival, malignant transformation, and cancer development. Furthermore, the pro-inflammatory tumor microenvironment environment (TME) contributes to EOC metastasis and chemoresistance. In this review we will discuss the roles inflammation and inflammatory mediators play in the development, progression, metastasis, and chemoresistance of EOC.

Polycystic Ovary Syndrome, Oligomenorrhea, and Risk of Ovarian Cancer Histotypes: Evidence from the Ovarian Cancer Association Consortium

Background: Polycystic ovary syndrome (PCOS), and one of its distinguishing characteristics, oligomenorrhea, have both been associated with ovarian cancer risk in some but not all studies. However, these associations have been rarely examined by ovarian cancer histotypes, which may explain the lack of clear associations reported in previous studies.Methods: We analyzed data from 14 case-control studies including 16,594 women with invasive ovarian cancer (n = 13,719) or borderline ovarian disease (n = 2,875) and 17,718 controls. Adjusted study-specific ORs were calculated using logistic regression and combined using random-effects meta-analysis. Pooled histotype-specific ORs were calculated using polytomous logistic regression.Results: Women reporting menstrual cycle length >35 days had decreased risk of invasive ovarian cancer compared with women reporting cycle length ≤35 days [OR = 0.70; 95% confidence interval (CI) = 0.58-0.84]. Decreased risk of invasive ovarian cancer was also observed among women who reported irregular menstrual cycles compared with women with regular cycles (OR = 0.83; 95% CI = 0.76-0.89). No significant association was observed between self-reported PCOS and invasive ovarian cancer risk (OR = 0.87; 95% CI = 0.65-1.15). There was a decreased risk of all individual invasive histotypes for women with menstrual cycle length >35 days, but no association with serous borderline tumors (Pheterogeneity = 0.006). Similarly, we observed decreased risks of most invasive histotypes among women with irregular cycles, but an increased risk of borderline serous and mucinous tumors (Pheterogeneity < 0.0001).Conclusions: Our results suggest that menstrual cycle characteristics influence ovarian cancer risk differentially based on histotype.Impact: These results highlight the importance of examining ovarian cancer risk factors associations by histologic subtype. Cancer Epidemiol Biomarkers Prev; 27(2); 174-82. ©2017 AACR.

MicroRNAs: tiny molecules with a significant role in mammalian follicular and oocyte development

The genetic regulation of female fertility (follicular development, oocyte maturation and early preimplantation embryo development) involves the spatio-temporal regulation of those genes that play key roles in various stages of the female reproductive axis. MicroRNAs (miRNAs), a class of small non-coding RNAs, are known to regulate the expression of a large proportion of such genes. In recent decades, multiple studies have aimed to determine the roles of these non-coding RNAs in mammalian follicular development, oocyte growth and embryo development. These studies have applied a variety of approaches, including conditional knockout of miRNA biogenesis genes, high-throughput sequencing technologies for pattern recognition in miRNA expression and loss- and gain-of-function of miRNAs in various animal models. In addition to the cellular miRNAs, a large variety of RNAs are found in circulation, being coupled with extracellular vesicles, proteins and lipids. Because of their potential as diagnostic markers for abnormal physiologies, there is increasing interest in the identification of extracellular miRNAs in various biological fluids and spent in vitro culture media. This review focuses on studies addressing the expression and potential role of cellular and extracellular miRNAs in mammalian follicular cell physiology and subsequent ovarian functionality and oocyte maturation.

Healthy eating index in women with polycystic ovary syndrome: A case-control study

BACKGROUND

Despite many effort to identify and control the factors involved in polycystic ovary syndrome (PCOS), there are no available reports indicating the association of healthy eating index (HEI) and PCOS.

OBJECTIVE

The present study has been conducted to examine the relationship between HEI and PCOS.

MATERIALS AND METHODS

In this case-control study, the study population comprised 297 women aged 20-40 yr referred to Baqiyatallah Hospital Clinics, Tehran, Iran in two groups: case group (n=99) and control group (n=198). The usual dietary data were collected using a validated 168-item semi-quantitative food frequency questionnaire. Standard anthropometric measurements (height, weight, and waist circumference) were also taken. Unconditional logistic regression was used to analyze the relationship between the PCOS and the HEI.

RESULTS

The mean age and body mass index of case and control groups were 29±5.5 vs. 29.5±6 yr and 26.6±4.8 vs. 26±4.2 kg/m², respectively (p=0.752, p=0.822). Mean HEI scores for the case and control groups were found to be 61 and 65, respectively. In final model and after adjustment for confounders, the prevalence of PCOS in subjects in the highest tertile HEI score was significantly (50%) less than those in the lowest tertile HEI score (OR=0.50; 95% CI: 0.25-0.74, p=0.001).

CONCLUSION

Our results suggest that HEI score is inversely associated with the risk of PCOS in adult women.