Circulating Estrogens and Postmenopausal Ovarian Cancer Risk in the Women's Health Initiative Observational Study

Quantitative analysis of 34 sex (pro)hormones, conjugates and bioactive oxidation products thereof in human plasma by GC- and LC-MS/MS and systematic investigation of overestimations of analyte concentrations not accounted for by method validation

When investigating endocrine disorders, it is essential to assess a comprehensive quantitative profile of sex (pro)hormones in plasma including conjugates. Thus, the present study aimed to develop and validate a comprehensive mass spectrometry-based multimethod combining the direct analysis of unconjugated sex (pro)hormones and oxidation products thereof (by GC), as well as their sulfates and glucuronides present in higher concentrations (by LC) with the indirect quantification of glucuronides present in lower concentrations after selective glucuronide hydrolysis (by GC) and its application to plasma derived from ten pre- and postmenopausal women and men each. Even guideline-compliant validation experiments cannot completely reflect overestimation of analyte concentrations due to effects depending on the individual ratio of analytes (i.e. chemical formation of analytes or incomplete removal of interfering analytes). Thus, the extent of processes not accounted for by the calibration strategy were investigated and maximum over- or underestimations of analyte concentrations were assessed for each plasma sample individually. 34 analytes were successfully calibrated, validated (median accuracy 101.1 %, median inter-day precision 8.1 %) and 31 were detected above the detection limit in plasma samples. The sporadic maximum individual over- or underestimation of analyte concentrations amounted to less than 20 %.

Associations of tubal ligation and hysterectomy with serum androgen and estrogen metabolites among postmenopausal women in the Women's Health Initiative Observational Study

PURPOSE

Hysterectomy is associated with subsequent changes in circulating hormone levels, but the evidence of an association for tubal ligation is unclear. We evaluated whether circulating concentrations of androgens and estrogens differ by tubal ligation or hysterectomy status in postmenopausal women from the Women's Health Initiative (WHI)-Observational Study (OS).

METHODS

Serum androgens and estrogens were measured in 920 postmenopausal women who did not use menopausal hormone therapy at the time of blood draw, of whom 139 self-reported a history of tubal ligation and 102 reported hysterectomy (with intact ovaries). Geometric mean hormone concentrations (GMs) and 95% confidence intervals (CIs) associated with a history of tubal ligation or hysterectomy (ever/never), as well as time since procedures, were estimated using adjusted linear regression with inverse probability of sampling weights to account for selection.

RESULTS

Circulating levels of 12 androgen/androgen metabolites and 20 estrogen/estrogen metabolites did not differ by tubal ligation status. Among women reporting prior hysterectomy compared to women without hysterectomy, we observed lower levels of several androgens (e.g., testosterone (nmol/L): GMyes 0.46 [95% CI:0.37-0.57] vs. GMno 0.62 [95% CI:0.53-0.72]) and higher levels of estrogen metabolites, for example, 2-hydroxyestrone-3-methyl ether (GMyes 11.1 [95% CI:8.95-13.9] pmol/L vs. GMno 8.70 [95% CI:7.38-10.3]) and 4-methoxyestrone (GMyes 6.50 [95% CI:5.05-8.37] vs. GMno 4.92 [95% CI:4.00-6.05]).

CONCLUSION

While we did not observe associations between prior tubal ligation and postmenopausal circulating hormone levels, our findings support that prior hysterectomy was associated with lower circulating testosterone levels and higher levels of some estrogen metabolites, which may have implications for future hormone-related disease risks.

17β-hydroxysteroid dehydrogenase type 1 improves survival in serous epithelial ovarian tumors

The incidence of ovarian cancer has been epidemiologically related to female reproductive events and hormone replacement therapy after menopause. This highlights the importance of evaluating the role of sexual steroid hormones in ovarian cancer by the expression of enzymes related to steroid hormone biosynthesis in the tumor cells. This study was aimed to evaluate the presence of 17β-hydroxysteroid dehydrogenase type 1 (17β-HSD1), aromatase and estrogen receptor alpha (ERα) in the tumor cells and their association with the overall survival in 111 patients diagnosed with primary ovarian tumors. Positive immunoreactivity for 17β-HSD1 was observed in 74% of the tumors. In the same samples, aromatase and ERα revealed 66% and 47% positivity, respectively. No association was observed of 17β-HSD1 expression with the histological subtypes and clinical stages of the tumor. The overall survival of patients was improved in 17β-HSD1-positive group in Kaplan-Meier analysis (P = 0.028), and 17β-HSD1 expression had a protective effect from multivariate proportional regression evaluation (HR = 0.44; 95% CI 0.24-0.9; P = 0.040). The improved survival was observed in serous epithelial tumors but not in nonserous ovarian tumors. The expression of 17β-HSD1 in the cells of the serous epithelial ovarian tumors was associated with an improved overall survival, whereas aromatase and ERα were not related to a better survival. The evaluation of hazard risk factors demonstrated that age and clinical stage showed worse prognosis, and 17β-HSD1 expression displayed a protective effect with a better survival outcome in patients of epithelial ovarian tumors.

Menopausal hormone therapy use and risk of ovarian cancer by race: the ovarian cancer in women of African ancestry consortium

BACKGROUND

Most studies examining post-menopausal menopausal hormone therapy (MHT) use and ovarian cancer risk have focused on White women and few have included Black women.

METHODS

We evaluated MHT use and ovarian cancer risk in Black (n = 800 cases, 1783 controls) and White women (n = 2710 cases, 8556 controls), using data from the Ovarian Cancer in Women of African Ancestry consortium. Logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for the association of MHT use with ovarian cancer risk, examining histotype, MHT type and duration of use.

RESULTS

Long-term MHT use, ≥10 years, was associated with an increased ovarian cancer risk for White women (OR = 1.38, 95%CI: 1.22-1.57) and the association was consistent for Black women (OR = 1.20, 95%CI: 0.81-1.78, pinteraction = 0.4). For White women, the associations between long-term unopposed estrogen or estrogen plus progesterone use and ovarian cancer risk were similar; the increased risk associated with long-term MHT use was confined to high-grade serous and endometroid tumors. Based on smaller numbers for Black women, the increased ovarian cancer risk associated with long-term MHT use was apparent for unopposed estrogen use and was predominately confined to other epithelial histotypes.

CONCLUSION

The association between long-term MHT use and ovarian cancer risk was consistent for Black and White women.

Do testosterone and sex hormone-binding globulin affect cancer risk? A Mendelian randomization and bioinformatics study

Using Mendelian Randomization (MR) and large-scale Genome-Wide Association Study (GWAS) data, this study aimed to investigate the potential causative relationship between testosterone and sex hormone-binding globulin (SHBG) levels and the onset of several cancers, including pathway enrichment analyses of single nucleotide polymorphisms (SNPs) associated with cancer allowed for a comprehensive bioinformatics approach, which offered a deeper biological understanding of these relationships. The results indicated that increased testosterone levels in women were associated with a higher risk of breast and cervical cancers but a lower risk of ovarian cancer. Conversely, increased testosterone was linked to lower stomach cancer risk for men, whereas high SHBG levels were related to decreased risks of breast and prostate cancers. The corresponding genes of the identified SNPs, as revealed by pathway enrichment analysis, were involved in significant metabolic and proliferative pathways. These findings emphasize the need for further research into the biological mechanisms behind these associations, paving the way for potential targeted interventions in preventing and treating these cancers.

Associations of Circulating Estrogens and Estrogen Metabolites with Fecal and Oral Microbiome in Postmenopausal Women in the Ghana Breast Health Study

The human fecal and oral microbiome may play a role in the etiology of breast cancer through modulation of endogenous estrogen metabolism. This study aimed to investigate associations of circulating estrogens and estrogen metabolites with the fecal and oral microbiome in postmenopausal African women. A total of 117 women with fecal (N = 110) and oral (N = 114) microbiome data measured by 16S rRNA gene sequencing, and estrogens and estrogen metabolites data measured by liquid chromatography tandem mass spectrometry were included. The outcomes were measures of the microbiome and the independent variables were the estrogens and estrogen metabolites. Estrogens and estrogen metabolites were associated with the fecal microbial Shannon index (global P < 0.01). In particular, higher levels of estrone (β = 0.36, P = 0.03), 2-hydroxyestradiol (β = 0.30, P = 0.02), 4-methoxyestrone (β = 0.51, P = 0.01), and estriol (β = 0.36, P = 0.04) were associated with higher levels of the Shannon index, while 16alpha-hydroxyestrone (β = -0.57, P < 0.01) was inversely associated with the Shannon index as indicated by linear regression. Conjugated 2-methoxyestrone was associated with oral microbial unweighted UniFrac as indicated by MiRKAT (P < 0.01) and PERMANOVA, where conjugated 2-methoxyestrone explained 2.67% of the oral microbial variability, but no other estrogens or estrogen metabolites were associated with any other beta diversity measures. The presence and abundance of multiple fecal and oral genera, such as fecal genera from families Lachnospiraceae and Ruminococcaceae, were associated with several estrogens and estrogen metabolites as indicated by zero-inflated negative binomial regression. Overall, we found several associations of specific estrogens and estrogen metabolites and the fecal and oral microbiome. IMPORTANCE Several epidemiologic studies have found associations of urinary estrogens and estrogen metabolites with the fecal microbiome. However, urinary estrogen concentrations are not strongly correlated with serum estrogens, a known risk factor for breast cancer. To better understand whether the human fecal and oral microbiome were associated with breast cancer risk via the regulation of estrogen metabolism, we conducted this study to investigate the associations of circulating estrogens and estrogen metabolites with the fecal and oral microbiome in postmenopausal African women. We found several associations of parent estrogens and several estrogen metabolites with the microbial communities, and multiple individual associations of estrogens and estrogen metabolites with the presence and abundance of multiple fecal and oral genera, such as fecal genera from families Lachnospiraceae and Ruminococcaceae, which have estrogen metabolizing properties. Future large, longitudinal studies to investigate the dynamic changes of the fecal and oral microbiome and estrogen relationship are needed.

Relation of circulating estrogens with hair relaxer and skin lightener use among postmenopausal women in Ghana

BACKGROUND

Hair relaxers and skin lighteners have been commonly used by African women, with suggestions that they may have hormonal activity.

OBJECTIVES

To investigate the relationship of hair relaxer and skin lightener use to serum estrogen/estrogen metabolite levels.

METHODS

We utilized the postmenopausal population-based controls of the Ghana Breast Health Study to estimate adjusted geometric means (GM) and 95% confidence intervals of individual circulating estrogen levels by hair relaxer/skin lightener exposure categories.

RESULTS

Of the 585 postmenopausal women included in our analysis, 80.2% reported hair relaxer use and 29.4% skin lightener use. Ever hair relaxer use was positively associated with estriol (adjusted GM 95.4 pmol/L vs. never 74.5, p value = 0.02) and 16-epiestriol (20.4 vs. 16.8, p value = 0.05) particularly among users of lye-based hair relaxers. Positive associations between scalp burns and unconjugated estrogens were observed (e.g., unconjugated estrone: 5+ scalp burns 76.9 [59.6-99.2] vs. no burns 64.0 [53.7-76.3], p-trend = 0.03). No association was observed between use of skin lighteners and circulating estrogens.

SIGNIFICANCE

This study presents evidence that circulating 16-pathway estrogens (i.e., estriol and 16-epiestriol) may be increased in users of lye-based hair relaxer products. Among hair relaxer users, unconjugated estrogen levels were elevated in women with a greater number of scalp burns.

IMPACT STATEMENT

In this population-based study of hair relaxer and skin lightener use among postmenopausal women in Ghana, altered estrogen metabolism was observed with hair relaxer use, particularly among women using lye-based products or with a greater number of scalp burns. In contrast, skin lightener use was not associated with differences in estrogen metabolism in this population. Continued investigation of the potential biological impact on breast cancer risk of hair relaxer use is warranted.

Racial differences in the association of body mass index and ovarian cancer risk in the OCWAA Consortium

BACKGROUND

Obesity disproportionately affects African American (AA) women and has been shown to increase ovarian cancer risk, with some suggestions that the association may differ by race.

METHODS

We evaluated body mass index (BMI) and invasive epithelial ovarian cancer (EOC) risk in a pooled study of case-control and nested case-control studies including AA and White women. We evaluated both young adult and recent BMI (within the last 5 years). Associations were estimated using multi-level and multinomial logistic regression models.

RESULTS

The sample included 1078 AA cases, 2582 AA controls, 3240 White cases and 9851 White controls. We observed a higher risk for the non-high-grade serous (NHGS) histotypes for AA women with obesity (ORBMI 30+= 1.62, 95% CI: 1.16, 2.26) and White women with obesity (ORBMI 30+= 1.20, 95% CI: 1.02, 2.42) compared to non-obese. Obesity was associated with higher NHGS risk in White women who never used HT (ORBMI 30+= 1.40, 95% CI: 1.08, 1.82). Higher NHGS ovarian cancer risk was observed for AA women who ever used HT (ORBMI 30+= 2.66, 95% CI: 1.15, 6.13), while in White women, there was an inverse association between recent BMI and risk of EOC and HGS in ever-HT users (EOC ORBMI 30+= 0.81, 95% CI: 0.69, 0.95, HGS ORBMI 30+= 0.73, 95% CI: 0.61, 0.88).

CONCLUSION

Obesity contributes to NHGS EOC risk in AA and White women, but risk across racial groups studied differs by HT use and histotype.

Microscopic Evaluation of Ovarian Surface Epithelium Following Treatment with Conjugated Estrogens in a Mouse Model

BACKGROUND

This study was designed to evaluate the effect of different concentrations of conjugated equine estrogens (CEE) on the ovarian epithelium of female CD1 mice.

METHODS

Twenty-four female mice at 7 months with irregular estrus cycles were randomly divided into four groups of 6 mice each. Group one was considered as a control group and received a daily dose of 0.5ml of propylene glycol, for three weeks, while those in the treatment groups received a daily dose of 14μg/kg, 28μg/kg and 56μg/kg conjugated equine estrogens, respectively.

RESULTS

The results from this study showed a strong correlation between elevated concentrations of CEE and histological changes in ovarian surface epithelium (OSE). They also showed that administration of high-dose estrogen created the conditions for excessive proliferation of OSE which may progress into the development of cysts in the ovaries.

CONCLUSION

This study concluded that high concentrations of CEE may increase the chances of developing epithelial ovarian cancer.

Anthropometric factors and the risk of ovarian cancer: A systematic review and meta-analysis

BACKGROUND

Excess weight is convincingly associated with several cancers, but the association with ovarian cancer is insufficiently clarified, in particular regarding subgroups defined by menopausal status and ovarian cancer histologic type.

AIMS

We carried out a comprehensive systematic review and meta-analysis of overweight and obesity in relation to ovarian cancer with focus on different subgroups.

METHODS AND RESULTS

We searched PubMed and Web of Science for relevant cohort and case-control studies published from inception to June 2021 in English language and using a clear definition of overweight and obesity. We combined maximally adjusted risk estimates using a random effects model. We analyzed data from 15 cohort and 26 case-control studies, including 28 471 ovarian cancer cases. The relative risk of ovarian cancer for overweight and obesity was 1.06 (95% confidence interval [CI] = 1.00-1.12) and 1.19 (95% CI = 1.11-1.28), respectively. Among premenopausal women, increased ovarian cancer risk was noted for overweight (RR 1.34; 95% CI = 1.03-1.75) and obesity (RR 1.51; 95% CI = 1.21-1.88). By comparison, among postmenopausal women no statistically significant association was found for overweight (RR 1.00; 95% CI 0.87-1.14) and obesity (RR1.03; 95% CI = 0.82-1.31). Increased risk was found for mucinous (RR 1.44; 95% CI = 1.03-2.01) and clear cell (RR 1.82; 95% CI = 1.11-2.99) ovarian cancer subtypes, but not for serous (RR1.12; 95% CI = 0.84-1.50;) and endometroid subtypes (RR1.24; 95% CI =0.96-1.60).

CONCLUSIONS

Obesity is associated with increased ovarian cancer risk. That relation is largely due to a positive association between adiposity and ovarian cancer among premenopausal but not postmenopausal women and among cases with mucinous and clear cell but not serous or endometrioid histology.

Measured body size and serum estrogen metabolism in postmenopausal women: the Ghana Breast Health Study

Background

Several anthropometric measures have been associated with hormone-related cancers, and it has been shown that estrogen metabolism in postmenopausal women plays an important role in these relationships. However, little is known about circulating estrogen levels in African women, and the relevance to breast cancer or breast cancer risk factors. To shed further light on the relationship of anthropometric factors and estrogen levels in African women, we examined whether measured body mass index (BMI), waist-to-hip ratio (WHR), height, and self-reported body size were associated with serum estrogens/estrogen metabolites in a cross-sectional analysis among postmenopausal population-based controls of the Ghana Breast Health Study.

Methods

Fifteen estrogens/estrogen metabolites were quantified using liquid chromatography-tandem mass spectrometry in serum samples collected from postmenopausal female controls enrolled in the Ghana Breast Health Study, a population-based case–control study conducted in Accra and Kumasi. Geometric means (GMs) of estrogens/estrogen metabolites were estimated using linear regression, adjusting for potential confounders.

Results

Measured BMI (≥ 30 vs. 18.5–24.9 kg/m2) was positively associated with parent estrogens (multivariable adjusted GM for unconjugated estrone: 78.90 (66.57–93.53) vs. 50.89 (43.47–59.59), p-value < 0.0001; and unconjugated estradiol: 27.83 (21.47–36.07) vs. 13.26 (10.37–16.95), p-value < 0.0001). Independent of unconjugated estradiol, measured BMI was associated with lower levels of 2-pathway metabolites and higher levels of 16-ketoestradriol. Similar patterns of association were found with WHR; however, the associations were not entirely independent of BMI. Height was not associated with postmenopausal estrogens/estrogen metabolite levels in African women.

Conclusions

We observed strong associations between measured BMI and parent estrogens and estrogen metabolite patterns that largely mirrored relations that have previously been associated with higher breast cancer risk in postmenopausal White women. The consistency of the BMI-estrogen metabolism associations in our study with those previously noted among White women suggests that estrogens likely explain part of the BMI-postmenopausal breast cancer risk in both groups. These findings merit evaluation in Black women, including prospective studies.

Analgesic use and circulating estrogens, androgens, and their metabolites in the Women's Health Initiative Observational Study

Though studies have observed inverse associations between use of analgesics (aspirin, non-aspirin nonsteroidal anti-inflammatory drugs [NSAIDs], and acetaminophen) and the risk of several cancers, the potential biological mechanisms underlying these associations are unclear. We investigated the relationship between analgesic use and serum concentrations of estrogens, androgens, and their metabolites among postmenopausal women to provide insights on whether analgesic use might influence endogenous hormone levels, which could in turn influence hormone-related cancer risk. The study included 1,860 postmenopausal women from two case-control studies nested within the Women's Health Initiative Observational Study. Analgesic use was reported at study baseline. Fifteen estrogens and estrogen metabolites and twelve androgens and androgen metabolites were quantified in baseline serum by liquid chromatography-tandem mass spectrometry. Linear regression with inverse probability weighting, stratified by menopausal hormone therapy (MHT) use, was used to estimate adjusted geometric mean concentrations of each hormone by analgesic use. Among women not currently using MHT (n=951), low-dose aspirin (<100 mg) use was associated with a higher serum concentration of estrone, estradiol, and 2,4, and 16 hydroxylated metabolites. Use of regular-dose aspirin ( {greater than or equal to} 100 mg), non-aspirin NSAIDs, and acetaminophen were not associated with serum concentrations of estrogens, androgens, or their metabolites. This study highlights the importance of examining aspirin use by dose and suggests that low-dose aspirin may influence endogenous estrogen concentrations.

Ovarian Cancer Risk in Relation to Blood Cholesterol and Triglycerides

BACKGROUND

The association between circulating cholesterol and triglyceride levels and ovarian cancer risk remains unclear.

METHODS

We prospectively evaluated the association between cholesterol [total, low-density lipoprotein (LDL-C), and high-density lipoprotein (HDL-C)] and triglycerides and ovarian cancer incidence in a case-control study nested in the Nurses' Health Study (NHS) and NHSII cohorts and a longitudinal analysis in the UK Biobank.

RESULTS

A total of 290 epithelial ovarian cancer cases in the NHS/NHSII and 551 cases in UK Biobank were diagnosed after blood collection. We observed a reduced ovarian cancer risk comparing the top to bottom quartile of total cholesterol [meta-analysis relative risk (95% confidence interval): 0.81 (0.65-1.01), P trend 0.06], with no heterogeneity across studies (P heterogeneity = 0.74). Overall, no clear patterns were observed for HDL-C, LDL-C, or triglycerides and ovarian cancer risk. Comparing triglyceride levels at clinically relevant cut-off points (>200 vs. ≤200 mg/dL) for cases diagnosed more than 2 years after blood draw saw a positive relationship with risk [1.57 (1.03-2.42); P heterogeneity = 0.003]. Results were similar by serous/non-serous histotype, menopausal status/hormone use, and body mass index.

CONCLUSIONS

Data from two large cohorts in the United States and United Kingdom suggest that total cholesterol levels may be inversely associated with ovarian cancer risk, while triglycerides may be positively associated with risk when assessed at least 2 years before diagnosis, albeit both associations were modest.

IMPACT

This analysis of two large prospective studies suggests that circulating lipid levels are not strongly associated with ovarian cancer risk. The positive triglyceride-ovarian cancer association warrants further evaluation.

Obesity, Height, and Serum Androgen Metabolism among Postmenopausal Women in the Women's Health Initiative Observational Study

BACKGROUND

Anthropometric measures, including obesity, are important risk factors for breast and endometrial cancers in postmenopausal women. It is unknown whether these risk factors are associated with androgen metabolism, another risk factor for these cancers.

METHODS

Using baseline data from 1,765 postmenopausal women in the Women's Health Initiative Observational Study, we conducted a cross-sectional analysis examining associations between anthropometric measures [current body mass index (BMI), waist-to-hip ratio (WHR), height, and recalled BMI at age 18) and serum androgen metabolites. Twelve androgens/androgen metabolites were quantified using LC-MS/MS. Geometric means of androgen/androgen metabolite concentrations were estimated using linear regression, adjusting for potential confounders and stratified by hormone therapy (HT) use.

RESULTS

Regardless of HT use, higher current BMI (≥30 vs. <25 kg/m2) was associated with higher serum concentrations of dehydroepiandrosterone sulfate (DHEAS), 5α-reduced glucuronide metabolites [androsterone-glucuronide (ADT-G), 5α-androstane-3α,17β diol-3-glucuronide (3α-diol-3G), 3α-diol-17-glucuronide (3α-diol-17G)], and DHEAS:DHEA ratio (all P trend ≤ 0.02). BMI was also positively associated with unconjugated estrone:androstenedione and unconjugated estradiol:testosterone ratios among never/former HT users (all P trend < 0.001) but not among current users (P-int < 0.001). WHR was positively associated with adrenal androgens and 5α-reduced glucuronide metabolites in obese women only (BMI ≥ 30 kg/m2; all P-trend ≤ 0.01). BMI at age 18 was inversely associated with adrenal androgens (DHEA, DHEAS, androstenedione, testosterone) and 5α-reduced glucuronide metabolites in never/former HT users (all P trend < 0.06). Height was not associated with androgen metabolites.

CONCLUSIONS

Current BMI is associated with androgen metabolism among postmenopausal women.

IMPACT

This study contributes to our understanding of the link between obesity and cancer risk in postmenopausal women.

Recreational Physical Activity, Sitting, and Androgen Metabolism among Postmenopausal Women in the Women's Health Initiative Observational Study

BACKGROUND

Prolonged sitting and physical inactivity are associated with higher circulating levels of estrogens. It is unknown whether these risk factors are associated with circulating androgens/androgen metabolites, another set of hormones implicated in the etiology of cancers in postmenopausal women.

METHODS

We conducted a cross-sectional analysis of 1,782 postmenopausal women in the Women's Health Initiative Observational Study. Serum concentrations of 12 androgens/androgen metabolites were quantified using liquid chromatography-tandem mass spectrometry. Physical activity and sitting time were self-reported at baseline. We performed linear regression to estimate geometric means (GM) of androgen/androgen metabolite concentrations (pmol/L) according to physical activity and sitting time, adjusting for potential confounders and stratified by menopausal hormone therapy (MHT) use.

RESULTS

Physical activity (≥15 vs. 0 MET-h/wk) was inversely associated with estrogen-to-androgen ratios among never/former MHT users (adj-GM = 37.5 vs. 49.6 unconjugated estrone:androstenedione; 20.2 vs. 30.3 unconjugated estradiol:testosterone; all P _trend ≤ 0.03) but was not associated among current MHT users. Prolonged sitting (≥10 vs. ≤5 h/d) was positively associated with these ratios among both never/former (adj-GM = 44.2 vs. 38.3, P _trend = 0.10; adj-GM = 23.4 vs. 20.2, P _trend = 0.17; respectively) and current MHT users (adj-GM = 197 vs. 147; 105 vs. 75.5; respectively; all P _trend ≤0.02), but the associations were statistically significant among current MHT users only. The associations persisted after adjustment for BMI. After adjustment for adrenal androgens, physical activity and sitting were not associated with androgen metabolites.

CONCLUSIONS

Physical activity and sitting were associated with serum estrogen-to-androgen ratios but not androgen metabolites.

IMPACT

This study contributes to our understanding of the link between physical activity, sitting, and cancer risk in postmenopausal women.

Estrogens and the Schrödinger's Cat in the Ovarian Tumor Microenvironment

Simple Summary

Ovarian cancer is a complex pathology for which we require effective screening and therapeutical strategies. Apart from the cancer cell portion, there exist plastic immune and non-immune cell populations, jointly constituting the context-adaptive tumor microenvironment, which is pivotal in tumorigenesis. Estrogens might be synthesized in the ovarian tumor tissue and actively contribute to the shaping of an immunosuppressive microenvironment. Current immune therapies have limited effectiveness as a multitude of factors influence the outcome. A thorough understanding of the ovarian cancer biology is crucial in the efforts to reestablish homeostasis.

Abstract

Ovarian cancer is a heterogeneous disease affecting the aging ovary, in concert with a complex network of cells and signals, together representing the ovarian tumor microenvironment. As in the “Schrödinger’s cat” thought experiment, the context-dependent constituents of the—by the time of diagnosis—well-established tumor microenvironment may display a tumor-protective and -destructive role. Systemic and locally synthesized estrogens contribute to the formation of a pro-tumoral microenvironment that enables the sustained tumor growth, invasion and metastasis. Here we focus on the estrogen biosynthetic and metabolic pathways in ovarian cancer and elaborate their actions on phenotypically plastic, estrogen-responsive, aging immune cells of the tumor microenvironment, altogether highlighting the multicomponent-connectedness and complexity of cancer, and contributing to a broader understanding of the ovarian cancer biology.

Association of Endogenous Pregnenolone, Progesterone, and Related Metabolites with Risk of Endometrial and Ovarian Cancers in Postmenopausal Women: The BFIT Cohort

BACKGROUND

Postmenopausal pregnenolone and/or progesterone levels in relation to endometrial and ovarian cancer risks have been infrequently evaluated. To address this, we utilized a sensitive and reliable assay to quantify prediagnostic levels of seven markers related to endogenous hormone metabolism.

METHODS

Hormones were quantified in baseline serum collected from postmenopausal women in a cohort study nested within the Breast and Bone Follow-up to the Fracture Intervention Trial (B∼FIT). Women using exogenous hormones at baseline (1992-1993) were excluded. Incident endometrial (n = 65) and ovarian (n = 67) cancers were diagnosed during 12 follow-up years and compared with a subcohort of 345 women (no hysterectomy) and 413 women (no oophorectomy), respectively. Cox models with robust variance were used to estimate cancer risk.

RESULTS

Circulating progesterone levels were not associated with endometrial [tertile (T)3 vs. T1 HR (95% confidence interval): 1.87 (0.85-4.11); P _trend = 0.17] or ovarian cancer risk [1.16 (0.58-2.33); 0.73]. Increasing levels of the progesterone-to-estradiol ratio were inversely associated with endometrial cancer risk [T3 vs. T1: 0.29 (0.09-0.95); 0.03]. Increasing levels of 17-hydroxypregnenolone were inversely associated with endometrial cancer risk [0.40 (0.18-0.91); 0.03] and positively associated with ovarian cancer risk [3.11 (1.39-6.93); 0.01].

CONCLUSIONS

Using sensitive and reliable assays, this study provides novel data that endogenous progesterone levels are not strongly associated with incident endometrial or ovarian cancer risks. 17-hydroxypregnenolone was positively associated with ovarian cancer and inversely associated with endometrial cancer.

IMPACT

While our results require replication in large studies, they provide further support of the hormonal etiology of endometrial and ovarian cancers.

SERPINB11 Expression Is Associated With Prognosis of High-grade Serous and Clear Cell Carcinoma of the Ovary

BACKGROUND/AIM

To evaluate the role of serine protease inhibitor B11 (SERPINB11) expression as a prognostic biomarker in high-grade serous carcinoma (HGSC) and clear cell carcinoma of the ovary (CCC).

MATERIALS AND METHODS

We obtained tumor tissues from patients with HGSC (n=145) and CCC (n=59). We evaluated immunohistochemically the expression of SERPINB11 and investigated whether SERPINB11 expression affects platinum-resistance and the prognosis of HGSC and CCC.

RESULTS

High expression of SERPINB11 was more common in CCC than in HGSC (57.6% vs. 28.3%; p<0.01), and SEPRINB11 expression did not correlate with platinum-resistance of HGSC and CCC. High expression of SERPINB11 was associated with worse progression-free survival and overall survival with marginal significance in HGSC; no relation between SERPINB11 expression and the prognosis of CCC was found.

CONCLUSION

SERPINB11 expression maybe a prognostic biomarker for HGSC.

Coronary artery calcium is associated with increased risk for lung and colorectal cancer in men and women: the Multi-Ethnic Study of Atherosclerosis (MESA)

AIMS

This study explored the association of coronary artery calcium (CAC) with incident cancer subtypes in the Multi-Ethnic Study of Atherosclerosis (MESA). CAC is an established predictor of cardiovascular disease (CVD), with emerging data also supporting independent predictive value for cancer. The association of CAC with risk for individual cancer subtypes is unknown.

METHODS AND RESULTS

We included 6271 MESA participants, aged 45-84 and without known CVD or self-reported history of cancer. There were 777 incident cancer cases during mean follow-up of 12.9 ± 3.1 years. Lung and colorectal cancer (186 cases) were grouped based on their strong overlap with CVD risk profile; prostate (men) and ovarian, uterine, and breast cancer (women) were considered as sex-specific cancers (in total 250 cases). Incidence rates and Fine and Gray competing risks models were used to assess relative risk of cancer-specific outcomes stratified by CAC groups or Log(CAC+1). The mean age was 61.7 ± 10.2 years, 52.7% were women, and 36.5% were White. Overall, all-cause cancer incidence increased with CAC scores, with rates per 1000 person-years of 13.1 [95% confidence interval (CI): 11.7-14.7] for CAC = 0 and 35.8 (95% CI: 30.2-42.4) for CAC ≥400. Compared with CAC = 0, hazards for those with CAC ≥400 were increased for lung and colorectal cancer in men [subdistribution hazard ratio (SHR): 2.2 (95% CI: 1.1-4.7)] and women [SHR: 2.2 (95% CI: 1.0-4.6)], but not significantly for sex-specific cancers across sexes.

CONCLUSION

CAC scores were associated with cancer risk in both sexes; however, this was stronger for lung and colorectal when compared with sex-specific cancers. Our data support potential synergistic use of CAC scores in the identification of both CVD and lung and colorectal cancer risk.

Ovarian Cancer Risk Factor Associations by Primary Anatomic Site: The Ovarian Cancer Cohort Consortium

BACKGROUND

Epithelial ovarian, fallopian tube, and primary peritoneal cancers have shared developmental pathways. Few studies have prospectively examined heterogeneity in risk factor associations across these three anatomic sites.

METHODS

We identified 3,738 ovarian, 337 peritoneal, and 176 fallopian tube incident cancer cases in 891,731 women from 15 prospective cohorts in the Ovarian Cancer Cohort Consortium. Associations between 18 putative risk factors and risk of ovarian, peritoneal, and fallopian tube cancer, overall and for serous and high-grade serous tumors, were evaluated using competing risks Cox proportional hazards regression. Heterogeneity was assessed by likelihood ratio tests.

RESULTS

Most associations did not vary by tumor site (P het ≥ 0.05). Associations between first pregnancy (P het = 0.04), tubal ligation (P het = 0.01), and early-adult (age 18-21 years) body mass index (BMI; P het = 0.02) and risk differed between ovarian and peritoneal cancers. The association between early-adult BMI and risk further differed between peritoneal and fallopian tube cancer (P het = 0.03). First pregnancy and tubal ligation were inversely associated with ovarian, but not peritoneal, cancer. Higher early-adult BMI was associated with higher risk of peritoneal, but not ovarian or fallopian tube, cancer. Patterns were generally similar when restricted to serous and high-grade serous cases.

CONCLUSIONS

Ovarian, fallopian tube, and primary peritoneal cancers appear to have both shared and distinct etiologic pathways, although most risk factors appear to have similar associations by anatomic site.

IMPACT

Further studies on the mechanisms underlying the differences in risk profiles may provide insights regarding the developmental origins of tumors arising in the peritoneal cavity and inform prevention efforts.

Estrone Is a Strong Predictor of Circulating Estradiol in Women Age 70 Years and Older

IMPORTANCE

After menopause, estradiol (E2) is predominately an intracrine hormone circulating in very low serum concentrations.

OBJECTIVE

The objective of this work is to examine determinants of E2 concentrations in women beyond age 70 years.

DESIGN AND SETTING

A cross-sectional, community-based study was conducted.

PARTICIPANTS

A total of 5325 women participated, with a mean age of 75.1 years (± 4.2 years) and not using any sex steroid, antiandrogen/estrogen, glucocorticoid, or antiglycemic therapy.

MAIN OUTCOME MEASURES

Sex steroids were measured by liquid chromatography-tandem mass spectrometry. Values below the limit of detection (LOD; E2 11 pmol/L [3 pg/mL] were assigned a value of LOD/√2 to estimate total E2.

RESULTS

E2 and estrone (E1) were below the LOD in 66.1% and 0.9% of women, respectively. The median (interdecile ranges) for E1 and detectable E2 were 181.2 pmol/L (range, 88.7-347.6 pmol/L) and 22.0 pmol/L (range, 11.0-58.7 pmol/L). Women with undetectable E2 vs detectable E2 were older (median age 74.1 years vs 73.8, P = .02), leaner (median body mass index [BMI] 26.8 kg/m2 vs 28.5, P < .001), and had lower E1, testosterone and DHEA concentrations (P < .001). A linear regression model, including age, BMI, E1, and testosterone, explained 20.9% of the variation in total E2, but explained only an additional 1.2% of variation over E1 alone. E1 and testosterone made significant contributions (r2 = 0.162, P < .001) in a model for the subset of women with detectable E2.

CONCLUSIONS

Our findings support E1 as a principal circulating estrogen and demonstrate a robust association between E1 and E2 concentrations in postmenopausal women. Taken together with prior evidence for associations between E1 and health outcomes, E1 should be included in studies examining associations between estrogen levels and health outcomes in postmenopausal women.

Serial endometrial thickness and risk of non-endometrial hormone-dependent cancers in postmenopausal women in UK Collaborative Trial of Ovarian Cancer Screening

OBJECTIVE

Estrogen is a well-established risk factor for various cancers. It causes endometrial proliferation, which is assessed routinely as endometrial thickness (ET) using transvaginal ultrasound (TVS). Only one previous study, restricted to endometrial and breast cancer, has considered ET and the risk of non-endometrial cancer. The aim of this study was to explore the association between baseline and serial ET measurements and nine non-endometrial hormone-sensitive cancers, in postmenopausal women, using contemporary statistical methodology that attempts to minimize the biases typical of endogenous serial data.

METHODS

This was a cohort study nested within the UK Collaborative Trial of Ovarian Cancer Screening (UKCTOCS). In the ultrasound arm of UKCTOCS, 50639 postmenopausal women, aged 50-74, underwent annual TVS examination, of whom 38 105 had a valid ET measurement, no prior hysterectomy and complete covariate data, and were included in this study. All women were followed up through linkage to national cancer registries. The effect of ET on the risk of six estrogen-dependent cancers (breast, ovarian, colorectal, bladder, lung and pancreatic) was assessed using joint models for longitudinal biomarker and time-to-event data, and Cox models were used to assess the association between baseline ET measurement and these six cancers in addition to liver cancer, gastric cancer and non-Hodgkin's lymphoma (NHL). All models were adjusted for current hormone-replacement therapy (HRT) use, body mass index, age at last menstrual period, parity and oral contraceptive pill use.

RESULTS

The 38 105 included women had a combined total of 267 567 (median, 8; interquartile range, 5-9) valid ET measurements. During a combined total of 407 838 (median, 10.9) years of follow-up, 1398 breast, 351 endometrial, 381 lung, 495 colorectal, 222 ovarian, 94 pancreatic, 79 bladder, 62 gastric, 38 liver cancers and 52 NHLs were registered. Using joint models, a doubling of ET increased significantly the risk of breast (hazard ratio (HR), 1.21; 95% CI, 1.09-1.36; P = 0.001), ovarian (HR, 1.39; 95% CI, 1.06-1.82; P = 0.018) and lung (HR, 1.25; 95% CI, 1.02-1.54; P = 0.036) cancers. There were no statistically significant associations between ET and the remaining six cancers.

CONCLUSION

Postmenopausal women with high/increasing ET on TVS are at increased risk of breast, ovarian and lung cancer. It is important that clinicians are aware of these risks, as TVS is a common investigation. © 2019 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of the International Society of Ultrasound in Obstetrics and Gynecology.

Coronary Artery Calcium as a Synergistic Tool for the Age- and Sex-Specific Risk of Cardiovascular and Cancer Mortality: The Coronary Artery Calcium Consortium

Background

Coronary artery calcium (CAC) is a predictor for the development of cardiovascular disease (CVD) and to a lesser extent cancer. The age‐ and sex‐specific relationship of CAC with CVD and cancer mortality is unknown.

Methods and Results

Asymptomatic patients aged 40 to 75 years old without known CVD were included from the CAC Consortium. We calculated sex‐specific mortality rates per 1000 person‐years’ follow‐up. Using parametric survival regression modeling, we determined the age‐ and sex‐specific CAC score at which the risk of death from CVD and cancer were equal. Among the 59 502 patients included in this analysis, the mean age was 54.9 (±8.5) years, 34% were women, and 89% were white. There were 671 deaths attributable to CVD and 954 deaths attributable to cancer over a mean follow‐up of 12±3 years. Among patients with CAC=0, cancer was the leading cause of death, the total mortality rate was low (women, 1.8; men, 1.5), and the CVD mortality rate was exceedingly low for women (0.3) and men (0.3). The age‐specific CAC score at which the risk of CVD and cancer mortality were equal had a U‐shaped relationship for women, while the relationship was exponential for men.

Conclusions

The age‐ and sex‐specific relationship of CAC with CVD and cancer mortality differed significantly for women and men. Our age‐ and sex‐specific CAC score provides a more precise estimate and further facilitates the use of CAC as a synergistic tool in strategies for the prediction and prevention of CVD and cancer mortality.

The Risk of Ovarian Cancer Increases with an Increase in the Lifetime Number of Ovulatory Cycles: An Analysis from the Ovarian Cancer Cohort Consortium (OC3)

Repeated exposure to the acute proinflammatory environment that follows ovulation at the ovarian surface and distal fallopian tube over a woman's reproductive years may increase ovarian cancer risk. To address this, analyses included individual-level data from 558,709 naturally menopausal women across 20 prospective cohorts, among whom 3,246 developed invasive epithelial ovarian cancer (2,045 serous, 319 endometrioid, 184 mucinous, 121 clear cell, 577 other/unknown). Cox models were used to estimate multivariable-adjusted HRs between lifetime ovulatory cycles (LOC) and its components and ovarian cancer risk overall and by histotype. Women in the 90th percentile of LOC (>514 cycles) were almost twice as likely to be diagnosed with ovarian cancer than women in the 10th percentile (<294) [HR (95% confidence interval): 1.92 (1.60-2.30)]. Risk increased 14% per 5-year increase in LOC (60 cycles) [(1.10-1.17)]; this association remained after adjustment for LOC components: number of pregnancies and oral contraceptive use [1.08 (1.04-1.12)]. The association varied by histotype, with increased risk of serous [1.13 (1.09-1.17)], endometrioid [1.20 (1.10-1.32)], and clear cell [1.37 (1.18-1.58)], but not mucinous [0.99 (0.88-1.10), P-heterogeneity = 0.01] tumors. Heterogeneity across histotypes was reduced [P-heterogeneity = 0.15] with adjustment for LOC components [1.08 serous, 1.11 endometrioid, 1.26 clear cell, 0.94 mucinous]. Although the 10-year absolute risk of ovarian cancer is small, it roughly doubles as the number of LOC rises from approximately 300 to 500. The consistency and linearity of effects strongly support the hypothesis that each ovulation leads to small increases in the risk of most ovarian cancers, a risk that cumulates through life, suggesting this as an important area for identifying intervention strategies. SIGNIFICANCE: Although ovarian cancer is rare, risk of most ovarian cancers doubles as the number of lifetime ovulatory cycles increases from approximately 300 to 500. Thus, identifying an important area for cancer prevention research.

Testosterone and Estrone Increase From the Age of 70 Years: Findings From the Sex Hormones in Older Women Study

CONTEXT

There is a lack of understanding of what is normal in terms of sex steroid levels in older women.

OBJECTIVE

To determine whether sex steroid levels vary with age in and establish reference ranges for women >70 years of age.

DESIGN AND SETTING

Cross-sectional, community-based study.

PARTICIPANTS

Included 6392 women ≥70 years of age.

MAIN OUTCOME MEASURES

Sex steroids measured by liquid chromatography-tandem mass spectrometry. A reference group, to establish sex steroid age-specific reference ranges, excluded women using systemic or topical sex steroid, antiandrogen or glucocorticoid therapy, or an antiglycemic agent.

RESULTS

The reference group of 5326 women had a mean age of 75.1 (±4.2) years, range of 70 to 94.7 years. Median values (range) were 181.2 pmol/L (3.7 to 5768.9) for estrone (E1), 0.38 nmol/L (0.035 to 8.56) for testosterone (T), 2.60 nmol/L (0.07 to 46.85) for dehydroepiandrosterone (DHEA), and 41.6 nmol/L (2.4 to 176.6) for SHBG. Estradiol and DHT were below method sensitivity in 66.1% and 72.7% of the samples, respectively. Compared with women aged 70 to 74 years, women aged ≥85 years had higher median levels of E1 (11.7%, P = 0.01), T (11.3%, P = 0.02), and SHBG (22.7%, P < 0.001) and lower DHEA (30% less, P < 0.001). Women with overweight and obesity had higher E1 (P < 0.001) and T (P < 0.03) and lower SHBG (P < 0.001) than did women with normal body mass index. Smokers had 17.2% higher median T levels (P = 0.005).

CONCLUSION

From the age of 70 years, T and E1 increase with age, despite a steady decline in DHEA. Whether E1 and T are biomarkers for longevity or contribute to healthy aging merits investigation.

Circulating estrogens and postmenopausal ovarian and endometrial cancer risk among current hormone users in the Women's Health Initiative Observational Study

PURPOSE

Menopausal hormone therapy (MHT) use induces alterations in circulating estrogens/estrogen metabolites, which may contribute to the altered risk of reproductive tract cancers among current users. Thus, the current study assessed associations between circulating estrogens/estrogen metabolites and ovarian and endometrial cancer risk among MHT users.

METHODS

We conducted a nested case-control study among postmenopausal women using MHT at baseline in the Women's Health Initiative Observational Study (179 ovarian cancers, 396 controls; 230 endometrial cancers, 253 controls). Multivariable logistic regression was utilized to estimate odds ratios and 95% confidence intervals overall and by subtype.

RESULTS

Estrogen/estrogen metabolite levels were not associated with overall or serous ovarian cancer risk, examined separately. However, unconjugated estradiol was positively associated with non-serous ovarian cancer risk [quintile 5 vs. quintile 1: 3.01 (1.17-7.73); p-trend = 0.03; p-het < 0.01]. Endometrial cancer risk was unrelated to estrogen/estrogen metabolite levels among women who took combined estrogen/progestin therapy (EPT).

CONCLUSIONS

These findings provide novel evidence that may support a heterogeneous hormonal etiology across ovarian cancer subtypes. Circulating estrogens did not influence endometrial cancer risk among women with EPT-induced high-estrogen levels. Larger studies are needed to delineate the relationship between ovarian/endometrial cancer subtypes and estrogen levels in the context of MHT use.

Circulating androgens and postmenopausal ovarian cancer risk in the Women's Health Initiative Observational Study

Our knowledge of epidemiologic risk factors for ovarian cancer supports a role for androgens in the pathogenesis of this disease; however, few studies have examined associations between circulating androgens and ovarian cancer risk. Using highly sensitive LC-MS/MS assays, we evaluated associations between pre-diagnostic serum levels of 12 androgens, including novel androgen metabolites that reflect androgen activity in tissues, and ovarian cancer risk among postmenopausal women in a nested case-control study in the Women's Health Initiative (WHI) Observational Study (OS). We frequency-matched 169 ovarian cancer cases to 410 controls from women enrolled in WHI-OS who were not using menopausal hormones at enrollment/blood draw. We estimated associations overall and by subtype (n = 102 serous/67 non-serous) using multivariable adjusted logistic regression. Androgen/androgen metabolite levels were not associated with overall ovarian cancer risk. In analyses by subtype, women with increased levels of androsterone-glucuronide (ADT-G) and total 5-α reduced glucuronide metabolites (markers of tissue-level androgenic activity) were at increased risk of developing non-serous ovarian cancer: ADT-G tertile (T)3 versus T1 odds ratio [OR] (95% confidence interval [CI]) 4.36 (1.68-11.32), p-heterogeneity 0.002; total glucuronide metabolites 3.63 (1.47-8.95), 0.002. Risk of developing serous tumors was unrelated to these markers. ADT-G and total glucuronide metabolites, better markers of tissue-level androgenic activity in women than testosterone, were associated with an increased risk of developing non-serous ovarian cancer. Our work demonstrates that sex steroid metabolism is important in the etiology of non-serous ovarian cancers and supports a heterogeneous hormonal etiology across histologic subtypes of ovarian cancer.

Steroidomics for the Prevention, Assessment, and Management of Cancers: A Systematic Review and Functional Analysis

Steroidomics, an analytical technique for steroid biomarker mining, has received much attention in recent years. This systematic review and functional analysis, following the PRISMA statement, aims to provide a comprehensive review and an appraisal of the developments and fundamental issues in steroid high-throughput analysis, with a focus on cancer research. We also discuss potential pitfalls and proposed recommendations for steroidomics-based clinical research. Forty-five studies met our inclusion criteria, with a focus on 12 types of cancer. Most studies focused on cancer risk prediction, followed by diagnosis, prognosis, and therapy monitoring. Prostate cancer was the most frequently studied cancer. Estradiol, dehydroepiandrosterone, and cortisol were mostly reported and altered in at least four types of cancer. Estrogen and estrogen metabolites were highly reported to associate with women-related cancers. Pathway enrichment analysis revealed that steroidogenesis; androgen and estrogen metabolism; and androstenedione metabolism were significantly altered in cancers. Our findings indicated that estradiol, dehydroepiandrosterone, cortisol, and estrogen metabolites, among others, could be considered oncosteroids. Despite noble achievements, significant shortcomings among the investigated studies were small sample sizes, cross-sectional designs, potential confounding factors, and problematic statistical approaches. More efforts are required to establish standardized procedures regarding study design, analytical procedures, and statistical inference.

Current strategies for quantification of estrogens in clinical research

Estrogens and their bioactive metabolites play key roles in regulating diverse processes in health and disease. In particular, estrogens and estrogenic metabolites have shown both protective and non-protective effects on disease pathobiology, implicating the importance of this steroid pathway in disease diagnostics and monitoring. All estrogens circulate in a wide range of concentrations, which in some patient cohorts can be extremely low. However, elevated levels of estradiol are reported in disease. For example, in pulmonary arterial hypertension (PAH) elevated levels have been reported in men and postmenopausal women. Conventional immunoassay techniques have come under scrutiny, with their selectivity, accuracy and precision coming into question. Analytical methodologies such as gas and liquid chromatography coupled to single and tandem mass spectrometric approaches (GC-MS, GC-MS/MS, LC-MS and LC-MS/MS) have been developed to quantify endogenous estrogens and in some cases their bioactive metabolites in biological fluids such as urine, serum, plasma and saliva. Liquid-liquid or solid-phase extraction approaches are favoured with derivatization remaining a necessity for detection in lower volumes of sample. The limits of quantitation of individual assays vary but are commonly in the range of 0.5-5 pg/mL for estrone and estradiol, with limits for their bioactive metabolites being higher. This review provides an overview of current approaches for measurement of unconjugated estrogens in biological matrices by MS, highlighting the advances in this field and the challenges remaining for routine use in the clinical and research environment.

[Obesity and Cancer]

In the past decades, obesity and overweight prevalence has been rising worldwide, in both men and women. In France, the prevalence of overweight in adults was 49% in 2015 (54% among men and 44% among women), including 17% of obese adults. According to the last evaluation performed by IARC in 2017, overweight and obesity are established risk factors for 13 cancer sites with risk estimates per 5kg/m2 varying largely depending on the cancer site. In 2015 in France, 5.4% of cancer cases could be attributed to excess weight, corresponding to 18,600 cases, including 3400 colon cancers, 2600 kidney cancers, 4500 breast cancers and 2500 endometrial cancers. Obesity is also related to worse prognosis for some cancers, in particular breast and colon cancers. Obesity in children and adolescents, also rising in many countries, has also been associated to an increase in adult cancer risk. A major cause of obesity is a disequilibrium in energy balance favoured by a diet rich in processed food, red meat, trans and saturated fatty acids, sweetened foods and beverages and poor in fruits and vegetables, legumes and whole grains. Main national and international recommendations to reduce the prevalence of obesity are to have a balanced diet and regular physical activity.

Postmenopausal Androgen Metabolism and Endometrial Cancer Risk in the Women's Health Initiative Observational Study

Background

After menopause, several androgens continue to be produced primarily by the adrenal glands; these can be converted into estrogens via aromatization or into androgen metabolites. It is unclear if androgens are associated with endometrial cancer risk independently of their being precursors to estrogens or if alternative metabolic pathways influence risk.

Methods

We measured prediagnostic serum concentrations of 12 androgens and their metabolites using highly sensitive liquid chromatography-tandem mass spectrometry assays in a nested case-control study of postmenopausal women from the Women's Health Initiative Observational Study (313 endometrial cancer case subjects, 354 matched control subjects). Estrogens were previously assayed. We used conditional logistic regression to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for endometrial cancer with adjustment for confounders.

Results

Compared to the lowest concentrations, the highest levels of adrenal androgens were associated with increased endometrial cancer risk: dehydroepiandrosterone (5th vs 1st quintile: OR = 1.85, 95% CI = 1.06 to 3.25), androstenedione (OR = 2.36, 95% CI = 1.34 to 4.16), and testosterone (OR = 1.91, 95% CI = 1.12 to 3.24). Downstream androgen metabolites were not associated with endometrial cancer. Although increased risks for the parent androgens were still suggested after adjustment for unconjugated estradiol, the associations attenuated, and with the exception of androstenedione, were no longer statistically significant. We also evaluated ratios of estrogens relative to their androgenic precursors; both higher unconjugated estrone:androstenedione and higher unconjugated estradiol:testosterone were associated with increased endometrial cancer risk.

Conclusions

We identified increased risks for endometrial cancer with the highest levels of adrenal androgens and high levels of estrogens relative to these androgens. As adrenal androgens can be aromatized to estrogens, this suggests androgens likely influence endometrial carcinogenesis via estrogen metabolism.

Serum glucose and insulin and risk of cancers of the breast, endometrium, and ovary in postmenopausal women

Limited evidence suggests that hyperinsulinemia may contribute to the risk of breast, endometrial, and, possibly, ovarian cancer. The aim of this study was to assess the association of serum glucose and insulin with risk of these cancers in postmenopausal women, while taking into account potential confounding and modifying factors. We studied 21 103 women with fasting baseline insulin and glucose measurements in a subsample of the Women's Health Initiative. The subsample was composed of four studies within Women's Health Initiative with different selection and sampling strategies. Over a mean of 14.7 years of follow-up, 1185 breast cancer cases, 156 endometrial cancer cases, and 130 ovarian cancer cases were diagnosed. We used Cox proportional hazards models to estimate hazard ratios (HRs) and 95% confidence intervals (95% CIs) by quartile of glucose or insulin. Serum insulin was positively associated with breast cancer risk (multivariable-adjusted HR for highest vs. lowest quartile 1.41, 95% CI: 1.16-1.72, Ptrend<0.0003), and glucose and insulin were associated with roughly a doubling of endometrial cancer risk (for glucose: HR: 2.00, 95% CI: 1.203.35, Ptrend=0.01; for insulin: HR: 2.39, 95% CI: 1.32-4.33, Ptrend=0.008). These associations remained unchanged or were slightly attenuated after mutual adjustment, adjustment for serum lipids, and assessment of possible reverse causation. Glucose and insulin showed no association with ovarian cancer. Our findings provide support for a role of insulin-related pathways in the etiology of cancers of the breast and endometrium. However, because of the unrepresentative nature of the sample, our results need confirmation in other populations.

The role of menopausal hormone therapy in women with or at risk of ovarian and breast cancers: Misconceptions and current directions

For women who are candidates for menopausal hormone therapy (MHT), estrogen can provide relief from symptomatic menopause, decrease rates of chronic illnesses, and improve health-related quality of life. However, confusion surrounds the evidence regarding the impact of exogenous estrogen and progesterone on the breast and ovary. Available data regarding the risks of MHT (estrogen and/or progestin) related to the development of breast and ovarian cancer are often inconsistent or incomplete. Modern molecular and genetic techniques have improved our understanding of the heterogeneity of breast and ovarian cancer. This enhanced understanding of the disease has impacted our understanding of carcinogenesis. Treatment options have evolved to be more targeted toward hormonal therapy for certain subtypes of disease, whereas cytotoxic chemotherapy remains the standard for other histological and molecular subtypes. The role of MHT in the breast and ovarian cancer survivor, as well as women who are at high risk for the development of hereditary breast and ovarian cancer, remains controversial despite evidence that this treatment can improve quality of life and survival outcomes. Through this article, we examine the evidence for and against the use of MHT with a focus on women who have or are at high risk for breast and ovarian cancer.

Estrogen metabolism in menopausal hormone users in the women's health initiative observational study: Does it differ between estrogen plus progestin and estrogen alone?

The WHI found an unexpected reduced breast cancer risk in women using CEE alone. We hypothesized CEE alone induces estrogen hydroxylation along the 2-pathway rather than the competing 16-pathway, a pattern linked to reduced postmenopausal breast cancer risk. One thousand eight hundred and sixty-four women in a WHIOS case-control study of estrogen metabolism and ovarian and endometrial cancer were studied of whom 609 were current E + P users (351 used CEE + MPA), while 272 used E alone (162 used CEE). Fifteen EM were measured, and analyses were conducted for each metabolite, hydroxylation pathway (2-, 4-, or 16-pathway) and ratios of pathway concentrations using inverse probability weighted linear regression. Compared to E + P users, all EM were higher in E alone users (significant for unconjugated estrone, total/conjugated estradiol, total/unconjugated 2-methoxyestrone, 4-methoxyestrone and unconjugated estriol). The relative concentrations of 2- and 4-pathway EM did not differ between the MHT users (2-pathway EM comprised 15% and 4-pathway EM <2% of the total), but 16-pathway EM were lower in E alone users (p = 0.036). Ratios of 2- and 4-pathway EM compared to 16-pathway EM were significantly higher in E alone compared to E + P users. Similar but not significant patterns were observed in CEE-alone and CEE + MPA users. Our data suggest that compared to E + P users, women using E alone have more extensive metabolism via the 2- vs. the competing 16-pathway. This is consistent with epidemiologic evidence of reduced postmenopausal breast cancer risk associated with this metabolic profile and may provide a clue to the breast cancer risk reduction in CEE alone users during the WHI.

Alcohol and oestrogen metabolites in postmenopausal women in the Women's Health Initiative Observational Study

Background:

Alcohol consumption is associated with an increased risk of several cancers. Potential mechanisms include altered oestrogen metabolism. Parent oestrogens metabolise into alternate pathways of oestrogen metabolites that may have variable effects on cancer pathogenesis. We examined associations of alcohol consumption with circulating oestrogen/oestrogen metabolites in postmenopausal women in the Women’s Health Initiative (WHI)-Observational Study (OS).

Methods:

We conducted a cross-sectional analysis of prediagnosis ovarian/endometrial cancer case-control data within WHI-OS (N=1864). Alcohol consumption was measured by validated food frequency questionnaire. Fasting serum parent oestrogens/oestrogen metabolites were assayed using liquid chromatography tandem mass-spectrometry. Geometric mean analyte concentrations (GM, pmol l⁻¹) were calculated by alcohol category using inverse-probability weighted linear regression, adjusting for venepuncture age/year, race, smoking, body mass index, years since menopause, oral contraceptive duration, caffeine intake, and physical activity.

Results:

There was evidence for a positive association between alcohol consumption and oestrone, oestradiol and 2-hydroxylation oestrogen metabolite concentrations among menopausal hormone therapy (MHT) users. We observed an association between liquor consumption and parent oestrogens among non-MHT users, who consumed larger doses of liquor than MHT users.

Conclusions:

Among postmenopausal women, the association between alcohol intake and parent oestrogen, but not oestrogen metabolite concentrations, may be influenced by MHT and type of alcohol.

Sitting, physical activity, and serum oestrogen metabolism in postmenopausal women: the Women's Health Initiative Observational Study

BACKGROUND

Prolonged sitting and lower levels of physical activity have been associated with increased levels of parent oestrogens (oestrone and oestradiol), the key hormones in female cancers, in postmenopausal women. However, it is unknown whether sitting and physical activity are associated with circulating oestrogen metabolite levels.

METHODS

Among 1804 postmenopausal women enrolled in the Women's Health Initiative Observational Study, 15 serum oestrogens/oestrogen metabolites were quantified using liquid chromatography-tandem mass spectrometry. Physical activity and sitting were self-reported via questionnaire. Using baseline, cross-sectional data, geometric means (GM) of oestrogens/oestrogen metabolites (pmol l^-1) were estimated using inverse probability weighted linear regression, adjusting for potential confounders and stratified on menopausal hormone therapy (MHT) use.

RESULTS

Longer time spent sitting (⩾10 vs ⩽5h per day) was associated with higher levels of unconjugated oestrone, independent of moderate- to vigorous-intensity physical activity and body mass index, among both never/former (GM=70.6 vs 57.7) and current MHT users (GM=242 vs 179) (P-trend ⩽0.03). Among never/former MHT users, sitting (⩾10 vs ⩽5h per day) was positively associated with 2-methoxyestradiol (GM=16.4 vs 14.4) and 4-methoxyestradiol (GM=2.36 vs 1.98) (P-trend ⩽0.04), independent of parent oestrogens. Inverse associations between moderate- to vigorous-intensity physical activity (⩾15 vs 0 metabolic equivalent task-hours per week) and parent oestrogens were found as expected. After adjustment for parent oestrogens, physical activity was not associated with oestrogen metabolites.

CONCLUSIONS

Our data suggest that prolonged sitting and lower moderate- to vigorous-intensity physical activity are associated with higher levels of postmenopausal oestrogens/oestrogen metabolites, the oestrogen metabolism patterns that have previously been associated with higher endometrial and breast cancer risk.

Androgens Are Differentially Associated with Ovarian Cancer Subtypes in the Ovarian Cancer Cohort Consortium

Invasive epithelial ovarian cancer (EOC) is the most lethal gynecologic malignancy. The etiology of EOC remains elusive; however, experimental and epidemiologic data suggest a role for hormone-related exposures in ovarian carcinogenesis and risk factor differences by histologic phenotypes and developmental pathways. Research on prediagnosis androgen concentrations and EOC risk has yielded inconclusive results, and analyses incorporating EOC subtypes are sparse. We conducted a pooled analysis of 7 nested case-control studies in the Ovarian Cancer Cohort Consortium to investigate the association between pre-diagnosis circulating androgens [testosterone, free testosterone, androstenedione, dehydroepiandrosterone sulfate (DHEAS)], sex hormone binding globulin (SHBG), and EOC risk by tumor characteristics (i.e., histology, grade, and stage). The final study population included 1,331 EOC cases and 3,017 matched controls. Multivariable conditional logistic regression was used to assess risk associations in pooled individual data. Testosterone was positively associated with EOC risk (all subtypes combined, ORlog2 = 1.12; 95% confidence interval 1.02-1.24); other endogenous androgens and SHBG were not associated with overall risk. Higher concentrations of testosterone and androstenedione associated with an increased risk in endometrioid and mucinous tumors [e.g., testosterone, endometrioid tumors, ORlog2 = 1.40 (1.03-1.91)], but not serous or clear cell. An inverse association was observed between androstenedione and high grade serous tumors [ORlog2 = 0.76 (0.60-0.96)]. Our analyses provide further evidence for a role of hormone-related pathways in EOC risk, with differences in associations between androgens and histologic subtypes of EOC. Cancer Res; 77(14); 3951-60. ©2017 AACR.

Clinical significance of the estrogen-modifying enzymes steroid sulfatase and estrogen sulfotransferase in epithelial ovarian cancer

17β-estradiol (E2) can contribute to the progression of epithelial ovarian cancer (EOC). Although the majority of patients with EOC are postmenopausal woman, when de novo estrogen production in the ovary has ceased, ovarian cancer cells remain exposed to estrogens synthesized locally in the cancer cells from inactive sulfonated steroid hormone precursors-such as estrone sulfate taken up from the circulation via the sulfatase pathway. An abundance of the estrogen-modifying enzymes, including estrogen-activating steroid sulfatase (STS) and estrogen-inactivating estrogen-sulfotransferase (SULT1E1), is important for providing active estrogen to EOC cells. Therefore, the present study determined the levels of SULT1E1, STS and estrogen receptor α (ERα) protein in paraffin-embedded specimens from 206 patients with Federation of Gynecology and Obstetrics stage II–IV EOC treated with debulking surgery and standard platinum-based adjuvant chemotherapy. The levels of STS, SULT1E1 and ERα were assessed by automated quantitative microscopy-based image analysis subsequent to immunohistochemical staining. Significantly higher SULT1E1 levels were observed in better differentiated EOC tumors compared to grade 3 EOC tumors (P=0.001). STS and SULT1E1 levels were positively associated with ERα abundance (P<0.001 and P=0.001, respectively). In advanced stage high-grade serous EOC (HGSOC; n=132), the most frequent and lethal type of ovarian cancer, SULT1E1 expression was significantly associated with a better overall survival rate (hazard ratio 0.66, 95% confidence interval, 0.45–0.94; P=0.005). These results highlight the importance of SULT1E1-mediated estrogen inactivation in EOC, particularly HGSOC. Therefore, targeting the sulfatase pathway is a potential endocrine therapeutic intervention for certain patients with estrogen-responsive EOC.

Anthropometric measures and serum estrogen metabolism in postmenopausal women: the Women's Health Initiative Observational Study

BACKGROUND

Several anthropometric measures have been associated with hormone-related cancers. However, it is unknown whether estrogen metabolism plays an important role in these relationships. We examined whether measured current body mass index (BMI), waist-to-hip ratio (WHR), height, and self-reported BMI at age 18 years were associated with serum estrogens/estrogen metabolites using baseline, cross-sectional data from 1835 postmenopausal women enrolled in the Women's Health Initiative Observational Study.

METHODS

Fifteen estrogens/estrogen metabolites were quantified using liquid chromatography-tandem mass spectrometry. Geometric means (GMs) of estrogens/estrogen metabolites (in picomoles per liter) were estimated using inverse probability weighted linear regression, adjusting for potential confounders and stratified on menopausal hormone therapy (MHT) use.

RESULTS

Among never or former MHT users, current BMI (≥30 vs. <25 kg/m²) was positively associated with parent estrogens (multivariable adjusted GM 432 vs. 239 pmol/L for estrone, 74 vs. 46 pmol/L for estradiol; p-trend < 0.001 for both) and all of the 2-, 4-, and 16-pathway estrogen metabolites evaluated (all p-trend ≤ 0.02). After additional adjustment for estradiol, unconjugated methylated 2-catechols were inversely associated (e.g., 2-methoxyestrone multivariable GM 9.3 vs. 12.0 pmol/L; p-trend < 0.001). Among current MHT users, current BMI was not associated with parent estrogens but was inversely associated with methylated catechols (e.g., 2-methoxyestrone multivariable GM 216 vs. 280 pmol/L; p-trend = 0.008). Similar patterns of association were found with WHR; however, the associations were not independent of BMI. Height and BMI at age 18 years were not associated with postmenopausal estrogens/estrogen metabolite levels.

CONCLUSIONS

Our data suggest that postmenopausal BMI is associated with increased circulating levels of parent estrogens and reduced methylation of catechol estrogen metabolites, the estrogen metabolism patterns that have previously been associated with higher breast cancer risk.

Dysregulation of Aromatase in Breast, Endometrial, and Ovarian Cancers: An Overview of Therapeutic Strategies

Aromatase is the rate-limiting enzyme in the biosynthesis of estrogens, which play crucial roles on a spectrum of developmental and physiological processes. The biological actions of estrogens are classically mediated by binding to two estrogen receptors (ERs), ERα and ERβ. Encoded by the cytochrome P450, family 19, subfamily A, polypeptide 1 (CYP19A1) gene, aromatase is expressed in a wide variety of tissues, as well as benign and malignant tumors, and is regulated in a pathway- and tissue-specific manner. Overexpression of aromatase, leading to elevated systemic levels of estrogen, is unequivocally linked to the pathogenesis and growth of a number malignancies, including breast, endometrium, and ovarian cancers. Aromatase inhibitors (AIs) are routinely used to treat estrogen-dependent breast cancers in postmenopausal women; however, their roles in endometrial and ovarian cancers remain obscure. While AI therapy is effective in hormone sensitive cancers, they diminish estrogen production throughout the body and, thus, generate undesirable side effects. Despite the effectiveness of AI therapy, resistance to endocrine therapy remains a major concern and is the leading cause of cancer death. Considerable advances, toward mitigating these issues, have evolved in conjunction with a number of histone deacetylase (HDAC) inhibitors for countering an assortment of diseases and cancers, including the aforesaid malignancies. HDACs are a family of enzymes that are frequently dysregulated in human tumors. This chapter will discuss the current understanding of aberrant regulation and expression of aromatase in breast, endometrial, and ovarian cancers, and potential therapeutic strategies for prevention and treatment of these life-threatening diseases.

Ovarian Cancer Risk Factors by Histologic Subtype: An Analysis From the Ovarian Cancer Cohort Consortium

PURPOSE

An understanding of the etiologic heterogeneity of ovarian cancer is important for improving prevention, early detection, and therapeutic approaches. We evaluated 14 hormonal, reproductive, and lifestyle factors by histologic subtype in the Ovarian Cancer Cohort Consortium (OC3).

PATIENTS AND METHODS

Among 1.3 million women from 21 studies, 5,584 invasive epithelial ovarian cancers were identified (3,378 serous, 606 endometrioid, 331 mucinous, 269 clear cell, 1,000 other). By using competing-risks Cox proportional hazards regression stratified by study and birth year and adjusted for age, parity, and oral contraceptive use, we assessed associations for all invasive cancers by histology. Heterogeneity was evaluated by likelihood ratio test.

RESULTS

Most risk factors exhibited significant heterogeneity by histology. Higher parity was most strongly associated with endometrioid (relative risk [RR] per birth, 0.78; 95% CI, 0.74 to 0.83) and clear cell (RR, 0.68; 95% CI, 0.61 to 0.76) carcinomas (P value for heterogeneity [P-het] < .001). Similarly, age at menopause, endometriosis, and tubal ligation were only associated with endometrioid and clear cell tumors (P-het ≤ .01). Family history of breast cancer (P-het = .008) had modest heterogeneity. Smoking was associated with an increased risk of mucinous (RR per 20 pack-years, 1.26; 95% CI, 1.08 to 1.46) but a decreased risk of clear cell (RR, 0.72; 95% CI, 0.55 to 0.94) tumors (P-het = .004). Unsupervised clustering by risk factors separated endometrioid, clear cell, and low-grade serous carcinomas from high-grade serous and mucinous carcinomas.

CONCLUSION

The heterogeneous associations of risk factors with ovarian cancer subtypes emphasize the importance of conducting etiologic studies by ovarian cancer subtypes. Most established risk factors were more strongly associated with nonserous carcinomas, which demonstrate challenges for risk prediction of serous cancers, the most fatal subtype.

Serum Estrogens and Estrogen Metabolites and Endometrial Cancer Risk among Postmenopausal Women

BACKGROUND

Although endometrial cancer is clearly influenced by hormonal factors, few epidemiologic studies have investigated the role of endogenous estrogens or especially estrogen metabolites.

METHODS

We conducted a nested case-control study within the Women's Health Initiative Observational Study (WHI-OS), a cohort of 93,676 postmenopausal women recruited between 1993 and 1998. Using baseline serum samples from women who were non-current hormone users with intact uteri, we measured 15 estrogens/estrogen metabolites via HPLC/MS-MS among 313 incident endometrial cancer cases (271 type I, 42 type II) and 354 matched controls, deriving adjusted ORs and 95% confidence intervals (CI) for overall and subtype-specific endometrial cancer risk.

RESULTS

Parent estrogens (estrone and estradiol) were positively related to endometrial cancer risk, with the highest risk observed for unconjugated estradiol (OR 5th vs. 1st quintile = 6.19; 95% CI, 2.95-13.03, Ptrend = 0.0001). Nearly all metabolites were significantly associated with elevated risks, with some attenuation after adjustment for unconjugated estradiol (residual risks of 2- to 3-fold). Body mass index (kg/m(2), BMI) relations were somewhat reduced after adjustment for estrogen levels. The association with unconjugated estradiol was stronger for type I than type II tumors (Phet = 0.01).

CONCLUSIONS

Parent estrogens as well as individual metabolites appeared to exert generalized uterotropic activity, particularly for type I tumors. The effects of obesity on risk were only partially explained by estrogens.

IMPACT

These findings enhance our understanding of estrogen mechanisms involved in endometrial carcinogenesis but also highlight the need for studying additional markers that may underlie the effects on risk of certain risk factors, for example, obesity. Cancer Epidemiol Biomarkers Prev; 25(7); 1081-9. ©2016 AACR.