Differential levels of circulating RNAs prior to endometrial cancer diagnosis.

Endometrial cancer (EC) is one of the most common female cancers and there is currently no routine screening strategy for early detection. An altered abundance of circulating microRNAs (miRNAs) and other RNA classes have the potential as early cancer biomarkers. We analyzed circulating RNA levels using small RNA sequencing, targeting RNAs in the size range of 17-47 nucleotides, in EC patients with samples collected prior to diagnosis compared to cancer-free controls. The analysis included 316 cases with samples collected 1-11 years prior to EC diagnosis, and 316 matched controls, both from the Janus Serum Bank cohort in Norway. We identified differentially abundant (DA) miRNAs, isomiRs, and small nuclear RNAs between EC cases and controls. The top EC DA miRNAs were miR-155-5p, miR-200b-3p, miR-589-5p, miR-151a-5p, miR-543, miR-485-5p, miR-625-p, and miR-671-3p. miR-200b-3p was previously reported to be among one of the top miRNAs with higher abundance in EC cases. We observed 47, 41, and 32 DA miRNAs for EC interacting with BMI, smoking status, and physical activity, respectively, including two miRNAs (miR-223-3p and miR-29b-3p) interacting with all three factors. The circulating RNAs are altered and show temporal dynamics prior to EC diagnosis. Notably, DA miRNAs for EC had the lowest q-value 4.39-6.66 years before diagnosis. Enrichment analysis of miRNAs showed that signaling pathways Fc epsilon RI, prolactin, toll-like receptor, and VEGF had the strongest associations.

Associations between lifestyle, health, and clinical characteristics and circulating oxysterols and cholesterol precursors in women diagnosed with breast cancer: a cross-sectional study.

Despite increasing evidence that cholesterol precursors and oxysterols, oxidized cholesterol metabolites, play a role in numerous pathological processes and diseases including breast cancer, little is known about correlates of these sterols in women with breast cancer. In this study, 2282 women with breast cancer and blood draw post diagnosis were included and cross-sectional associations between circulating levels of 15 sterols/oxysterols and (a) lifestyle, anthropometric, reproductive characteristics, (b) comorbidities and medication use, and (c) breast cancer tumor and treatment characteristics were calculated using generalized linear models. Obesity was strongly associated with circulating levels of 7-dehydrocholesterol (DC) (body mass index ≥ 30 vs. 18.5-24.9 kg/m2: 51.7% difference) and 7-ketocholesterol (KC) (40.0% difference). After adjustment for BMI, comorbidities such as cardiovascular disease were associated with higher levels of 7-DC (26.1% difference) and lower levels of desmosterol (- 16.4% difference). Breast cancer tumor characteristics including hormone receptor status, tumor stage, and endocrine therapy were associated with lanosterol, 24-DHLan, 7b-HC, and THC (e.g., THC; tumor stage IIIa vs. I: 36.9% difference). Weaker associations were observed for lifestyle characteristics and for any of the other oxysterols. The findings of this study suggest that cholesterol precursors are strongly associated with metabolic factors, while oxysterols are associated with breast cancer tumor characteristics, warranting further investigation into the role of cholesterol precursors and oxysterols in women with breast cancer and other populations.

Circulating oxysterols and prognosis among women with a breast cancer diagnosis: results from the MARIE patient cohort.

BACKGROUND: Breast cancer is the most commonly diagnosed cancer in women worldwide, and underlying mechanistic pathways associated with breast cancer-specific and non-breast cancer-related deaths are of importance. Emerging evidence suggests a role of oxysterols, derivates of cholesterol, in multiple chronic diseases including breast cancer and coronary artery diseases. However, associations between oxysterols and survival have been minimally studied in women diagnosed with breast cancer. In this large breast cancer patient cohort, we evaluated associations between a panel of circulating oxysterols and mortality and recurrence outcomes. METHODS: Concentrations of 13 circulating oxysterols representing different pathways of cholesterol metabolism were quantified using liquid-chromatography mass-spectrometry. Associations between baseline levels of oxysterols and cause-specific mortality outcomes and recurrence following a breast cancer diagnosis were assessed in 2282 women from the MARIE study over a median follow-up time of 11 years. We calculated hazard ratios (HR) and 95% confidence intervals (CI) using multivariable Cox proportional hazard models and competing risks models. RESULTS: We observed no associations for circulating oxysterols and breast cancer-specific outcomes. Higher levels of six oxysterols were associated with an increased risk of cardiovascular disease death, including 24S-hydroxycholesterol (alternative bile acid pathway, HRlog2 = 1.73 (1.02, 2.93)), lanosterol (cholesterol biosynthesis pathway, HRlog2 = 1.95 (1.34, 2.83)), 7-ketocholesterol (HRlog2 = 1.26 (1.03, 1.55)), 5α,6α-epoxycholesterol (HRlog2 = 1.34 (1.02-1.77)), and 5a,6ß-dihydroxycholestanol (HRlog2 = 1.34 (1.03, 1.76)). After adjusting for multiple comparisons, none of the associations were statistically significant. CONCLUSION: We provide first evidence on a range of circulating oxysterols and mortality following a breast cancer diagnosis, contributing to a better understanding of associations between different pathways of cholesterol metabolism and prognosis in women with a breast cancer diagnosis. The findings of this study suggest circulating oxysterols may be associated with cardiovascular mortality among women diagnosed with breast cancer. Further studies are needed to evaluate these oxysterols as potential markers of risk for cardiovascular mortality among women with a breast cancer diagnosis as well as their clinical potential.

Endogenous estrogen receptor modulating oxysterols and breast cancer prognosis: Results from the MARIE patient cohort.

BACKGROUND: 27-hydroxycholesterol (HC) and 25-HC were identified as endogenous selective estrogen receptor modulators (SERMs) and estrogen receptor (ER) modulators, respectively. They are hypothesized to play a role in multiple physiologic processes and pathologies, including breast cancer development and progression. METHODS: We evaluated circulating 27-HC and 25-HC, and outcomes following a breast cancer diagnosis in 2282 women from the MARIE study over median follow-up of 11.6 years. 27-HC and 25-HC were quantified by liquid chromatography-mass spectrometry. We calculated hazard ratios (HR) and 95% confidence intervals [CI] using multivariable Cox Proportional Hazards regression. RESULTS: We observed no associations between 27-HC and breast cancer prognosis overall. Associations between 27-HC and survival differed by circulating estradiol concentrations and endocrine therapy, but not by hormone receptor status. Among women with estradiol levels below the median (0.08 nM), 27-HC was associated with higher risk of all-cause mortality (HRlog2 = 1.80 [1.20-2.71]) and breast cancer-specific mortality (HRlog2 = 1.95 [1.14-3.31]). No associations were observed in women with estradiol levels above the median. Higher 25-HC levels were associated with lower risk of recurrence (HRlog2 = 0.87 [0.77-0.98]). CONCLUSION: Associations between 27-HC and breast cancer prognosis varied by circulating estradiol levels and endocrine therapy. Less consistent results were observed for 25-HC.

Characterization of ovarian cancer survival by histotype and stage: A nationwide study in Norway.

Contemporary population-based data on ovarian cancer survival using current subtype classifications and by surgical status are sparse. We evaluated 1-, 3-, 5- and 7-year relative (and overall) survival, and excess hazards in patients with borderline tumors or invasive epithelial ovarian cancer diagnosed 2012 to 2021 in a nationwide registry-based cohort in Norway. Outcomes were evaluated by histotype, FIGO stage, cytoreduction surgery and residual disease. Overall survival was evaluated for non-epithelial ovarian cancer. Survival of women with borderline ovarian tumors was excellent (≥98.0% 7-year relative survival). Across all evaluated invasive epithelial ovarian cancer histotypes, 7-year relative survival for cases diagnosed with stages I or II disease was ≥78.3% (stage II high-grade serous). Survival for ovarian cancers diagnosed at stage ≥III differed substantially by histotype and time since diagnosis (eg, stage III, 5-year relative survival from 27.7% [carcinosarcomas] to 76.2% [endometrioid]). Overall survival for non-epithelial cases was good (91.8% 5-year overall survival). Women diagnosed with stage III or IV invasive epithelial ovarian cancer and with residual disease following cytoreduction surgery had substantially better survival than women not operated. These findings were robust to restriction to women with high reported functional status scores. Patterns for overall survival were similar to those for relative survival. We observed relatively good survival with early stage at diagnosis even for the high grade serous histotype. Survival for patients diagnosed at stage ≥III invasive epithelial ovarian cancer was poor for all but endometrioid disease. There remains an urgent need for strategies for risk reduction and earlier detection, together with effective targeted treatments.

Physical activity and breast cancer survival: results from the Nurses' Health Studies.

BACKGROUND: Physical activity is generally associated with better outcomes following diagnosis; however, few studies have evaluated change in pre- to postdiagnosis activity and repeated measures of activity by intensity and type. METHODS: We evaluated physical activity and survival following a breast cancer diagnosis in the Nurses' Health Study and Nurses' Health Study II (n = 9308 women, n = 1973 deaths). Physical activity was evaluated as updated cumulative average of metabolic equivalent of task (MET)-h/wk (assigned per activity based on duration and intensity) and change in pre- to postdiagnosis activity. Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). RESULTS: Higher postdiagnosis activity was inversely associated with breast cancer-specific mortality in categories from ≥9 MET-h/wk (vs <3 MET h/wk, HR≥9 to <18 = 0.74 [95% CI = 0.55 to 0.99]; HR≥27 = 0.69 [95% CI = 0.50 to 0.95]; Ptrend = .04) and all-cause mortality from ≥3 MET-h/wk (HR≥3 to <9 = 0.73 [95% CI = 0.61 to 0.88]; HR≥27 = 0.51 [95% CI = 0.41 to 0.63]; Ptrend < .001). Associations were predominantly observed for estrogen receptor-positive tumors and in postmenopausal women. Walking was associated with lower risk of all-cause mortality (≥9 vs <3 MET-h/wk, HR= 0.69 [95% CI = 0.57 to 0.84]) as was strength training. Relative to stable activity pre- to postdiagnosis (±3 MET-h/wk), increases from ≥3 to 9 MET-h/wk were associated with lower all-cause mortality risk (Ptrend < .001). Results were robust to adjustment for prediagnosis physical activity. CONCLUSIONS: Physical activity was associated with lower risk of death following diagnosis. Increased pre- to postdiagnosis activity corresponding to at least 1-3 h/wk of walking was associated with lower risk of death. These results provide further impetus for women to increase their activity after a breast cancer diagnosis, though reverse causation cannot be fully excluded.

Association of circulating free and total oxysterols in breast cancer patients.

OBJECTIVES: Oxysterols, a family of oxidized cholesterol derivates, are of increasing interest due to their role in cancer development and progression. Some oxysterols are estrogen receptor modulators and thus of particular interest in breast cancer research. In human studies, two forms of circulating oxysterols are commonly evaluated: "free" (unesterified) and "total" (esterified and unesterified). However, associations between free and total oxysterols are not well established. We addressed this knowledge gap in a pilot study by evaluating correlations between the free and the total form of each of the circulating oxysterols (free vs. total), and pairwise associations within the panel of total oxysterols (total vs. total) and the panel of free oxysterols (free vs. free). METHODS: Concentrations of oxysterols and other non-cholesterol sterols were quantified in blood samples of 27 breast cancer patients from the MARIE breast cancer patient cohort using liquid chromatography mass spectrometry. We used Spearman rank correlations to assess associations. Overall, 12 oxysterols (including 27-hydroxycholesterol (HC), 25-HC, 24S-HC, 7a-HC, 5a6a-epoxycholesterol) and five sterols (including lanosterol and desmosterol) were analyzed. RESULTS: Strong correlations (r≥0.82) were observed for seven circulating free and total oxysterols/sterols. The free and total form of 27-HC (r=0.63), 25-HC (r=0.54), and two more oxysterols were weaker correlated. Correlation patterns in the panel of total oxysterols/sterols and the panel of free oxysterols/sterols were similar. CONCLUSIONS: These findings demonstrate that concentrations of most free and total oxysterols/sterols are strongly correlated. We provide further insight into the interrelationships between oxysterols in breast cancer patients.

In-depth evaluation of machine learning methods for semi-automating article screening in a systematic review of mechanistic literature.

We aimed to evaluate the performance of supervised machine learning algorithms in predicting articles relevant for full-text review in a systematic review. Overall, 16,430 manually screened titles/abstracts, including 861 references identified relevant for full-text review were used for the analysis. Of these, 40% (n = 6573) were sub-divided for training (70%) and testing (30%) the algorithms. The remaining 60% (n = 9857) were used as a validation set. We evaluated down- and up-sampling methods and compared unigram, bigram, and singular value decomposition (SVD) approaches. For each approach, Naïve Bayes, Support Vector Machines (SVM), regularized logistic regressions, neural networks, random forest, Logit boost, and XGBoost were implemented using simple term frequency or Tf-Idf feature representations. Performance was evaluated using sensitivity, specificity, precision and area under the Curve. We combined predictions of the best-performing algorithms (Youden Index ≥0.3 with sensitivity/specificity≥70/60%). In a down-sample unigram approach, Naïve Bayes, SVM/quanteda text models with Tf-Idf, and linear SVM e1071 package with Tf-Idf achieved >90% sensitivity at specificity >65%. Combining the predictions of the 10 best-performing algorithms improved the performance to reach 95% sensitivity and 64% specificity in the validation set. Crude screening burden was reduced by 61% (5979) (adjusted: 80.3%) with 5% (27) false negativity rate. All the other approaches yielded relatively poorer performances. The down-sampling unigram approach achieved good performance in our data. Combining the predictions of algorithms improved sensitivity while screening burden was reduced by almost two-third. Implementing machine learning approaches in title/abstract screening should be investigated further toward refining these tools and automating their implementation.

Prospective evaluation of 92 serum protein biomarkers for early detection of ovarian cancer.

BACKGROUND: CA125 is the best available yet insufficiently sensitive biomarker for early detection of ovarian cancer. There is a need to identify novel biomarkers, which individually or in combination with CA125 can achieve adequate sensitivity and specificity for the detection of earlier-stage ovarian cancer. METHODS: In the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort, we measured serum levels of 92 preselected proteins for 91 women who had blood sampled ≤18 months prior to ovarian cancer diagnosis, and 182 matched controls. We evaluated the discriminatory performance of the proteins as potential early diagnostic biomarkers of ovarian cancer. RESULTS: Nine of the 92 markers; CA125, HE4, FOLR1, KLK11, WISP1, MDK, CXCL13, MSLN and ADAM8 showed an area under the ROC curve (AUC) of ≥0.70 for discriminating between women diagnosed with ovarian cancer and women who remained cancer-free. All, except ADAM8, had shown at least equal discrimination in previous case-control comparisons. The discrimination of the biomarkers, however, was low for the lag-time of >9-18 months and paired combinations of CA125 with any of the 8 markers did not improve discrimination compared to CA125 alone. CONCLUSION: Using pre-diagnostic serum samples, this study identified markers with good discrimination for the lag-time of 0-9 months. However, the discrimination was low in blood samples collected more than 9 months prior to diagnosis, and none of the markers showed major improvement in discrimination when added to CA125.

Prediagnostic alterations in circulating bile acid profiles in the development of hepatocellular carcinoma.

Bile acids (BAs) play different roles in cancer development. Some are carcinogenic and BA signaling is also involved in various metabolic, inflammatory and immune-related processes. The liver is the primary site of BA synthesis. Liver dysfunction and microbiome compositional changes, such as during hepatocellular carcinoma (HCC) development, may modulate BA metabolism increasing concentration of carcinogenic BAs. Observations from prospective cohorts are sparse. We conducted a study (233 HCC case-control pairs) nested within a large observational prospective cohort with blood samples taken at recruitment when healthy with follow-up over time for later cancer development. A targeted metabolomics method was used to quantify 17 BAs (primary/secondary/tertiary; conjugated/unconjugated) in prediagnostic plasma. Odd ratios (OR) for HCC risk associations were calculated by multivariable conditional logistic regression models. Positive HCC risk associations were observed for the molar sum of all BAs (ORdoubling  = 2.30, 95% confidence intervals [CI]: 1.76-3.00), and choline- and taurine-conjugated BAs. Relative concentrations of BAs showed positive HCC risk associations for glycoholic acid and most taurine-conjugated BAs. We observe an association between increased HCC risk and higher levels of major circulating BAs, from several years prior to tumor diagnosis and after multivariable adjustment for confounders and liver functionality. Increase in BA concentration is accompanied by a shift in BA profile toward higher proportions of taurine-conjugated BAs, indicating early alterations of BA metabolism with HCC development. Future studies are needed to assess BA profiles for improved stratification of patients at high HCC risk and to determine whether supplementation with certain BAs may ameliorate liver dysfunction.

High Prediagnosis Inflammation-Related Risk Score Associated with Decreased Ovarian Cancer Survival.

BACKGROUND: There is suggestive evidence that inflammation is related to ovarian cancer survival. However, more research is needed to identify inflammation-related factors that are associated with ovarian cancer survival and to determine their combined effects. METHODS: This analysis used pooled data on 8,147 women with invasive epithelial ovarian cancer from the Ovarian Cancer Association Consortium. The prediagnosis inflammation-related exposures of interest included alcohol use; aspirin use; other nonsteroidal anti-inflammatory drug use; body mass index; environmental tobacco smoke exposure; history of pelvic inflammatory disease, polycystic ovarian syndrome, and endometriosis; menopausal hormone therapy use; physical inactivity; smoking status; and talc use. Using Cox proportional hazards models, the relationship between each exposure and survival was assessed in 50% of the data. A weighted inflammation-related risk score (IRRS) was developed, and its association with survival was assessed using Cox proportional hazards models in the remaining 50% of the data. RESULTS: There was a statistically significant trend of increasing risk of death per quartile of the IRRS [HR = 1.09; 95% confidence interval (CI), 1.03-1.14]. Women in the upper quartile of the IRRS had a 31% higher death rate compared with the lowest quartile (95% CI, 1.11-1.54). CONCLUSIONS: A higher prediagnosis IRRS was associated with an increased mortality risk after an ovarian cancer diagnosis. Further investigation is warranted to evaluate whether postdiagnosis exposures are also associated with survival. IMPACT: Given that pre- and postdiagnosis exposures are often correlated and many are modifiable, our study results can ultimately motivate the development of behavioral recommendations to enhance survival among patients with ovarian cancer.

Endogenous Circulating Sex Hormone Concentrations and Colon Cancer Risk in Postmenopausal Women: A Prospective Study and Meta-Analysis.

Background: Observational studies have consistently reported that postmenopausal hormone therapy use is associated with lower colon cancer risk, but epidemiologic studies examining the associations between circulating concentrations of endogenous estrogens and colorectal cancer have reported inconsistent results. Methods: We investigated the associations between circulating concentrations of estrone, estradiol, free estradiol, testosterone, free testosterone, androstenedione, dehydroepiandrosterone (DHEA), progesterone, and sex hormone-binding globulin (SHBG) with colon cancer risk in a nested case-control study of 1028 postmenopausal European women (512 colon cancer cases, 516 matched controls) who were noncurrent users of exogenous hormones at blood collection. Multivariable conditional logistic regression models were used to compute odds ratios and 95% confidence intervals to evaluate the association between circulating sex hormones and colon cancer risk. We also conducted a dose-response meta-analysis of prospective studies of circulating estrone and estradiol with colorectal, colon, and rectal cancer risk in postmenopausal women. All statistical tests were 2-sided. Results: In the multivariable model, a nonstatistically significantly positive relationship was found between circulating estrone and colon cancer risk (odds ratio per log2 1-unit increment = 1.17 [95% confidence interval = 1.00 to 1.38]; odds ratioquartile4-quartile1 = 1.33 [95% confidence interval = 0.89 to 1.97], P trend = .20). Circulating concentrations of estradiol, free estradiol, testosterone, free testosterone, androstenedione, DHEA, progesterone, and SHBG were not associated with colon cancer risk. In the dose-response meta-analysis, no clear evidence of associations were found between circulating estradiol and estrone concentrations with colorectal, colon, and rectal cancer risk. Conclusion: Our observational and meta-analysis results do not support an association between circulating concentrations of endogenous sex hormones and colon or rectal cancer in postmenopausal women.

Adiposity and Endometrial Cancer Risk in Postmenopausal Women: A Sequential Causal Mediation Analysis.

BACKGROUND: Adiposity increases endometrial cancer risk, possibly through inflammation, hyperinsulinemia, and increasing estrogens. We aimed to quantify the mediating effects of adiponectin (anti-inflammatory adipocytokine); IL6, IL1-receptor antagonist, TNF receptor 1 and 2, and C-reactive protein (inflammatory status biomarkers); C-peptide (hyperinsulinemia biomarker); and free estradiol and estrone (estrogen biomarkers) in the adiposity-endometrial cancer link in postmenopausal women. METHODS: We used data from a case-control study within the European Prospective Investigation into Cancer and Nutrition (EPIC). Eligible women did not have cancer, hysterectomy, and diabetes; did not use oral contraceptives or hormone therapy; and were postmenopausal at recruitment. Mediating pathways from adiposity to endometrial cancer were investigated by estimating natural indirect (NIE) and direct (NDE) effects using sequential mediation analysis. RESULTS: The study included 163 cases and 306 controls. The adjusted OR for endometrial cancer for body mass index (BMI) ≥30 versus ≥18.5-<25 kg/m2 was 2.51 (95% confidence interval, 1.26-5.02). The ORsNIE were 1.95 (1.01-3.74) through all biomarkers [72% proportion mediated (PM)] decomposed as: 1.35 (1.06-1.73) through pathways originating with adiponectin (33% PM); 1.13 (0.71-1.80) through inflammation beyond (the potential influence of) adiponectin (13% PM); 1.05 (0.88-1.24) through C-peptide beyond adiponectin and inflammation (5% PM); and 1.22 (0.89-1.67) through estrogens beyond preceding biomarkers (21% PM). The ORNDE not through biomarkers was 1.29 (0.54-3.09). Waist circumference gave similar results. CONCLUSIONS: Reduced adiponectin and increased inflammatory biomarkers, C-peptide, and estrogens mediated approximately 70% of increased odds of endometrial cancer in women with obesity versus normal weight. IMPACT: If replicated, these results could have implications for identifying targets for intervention to reduce endometrial cancer risk in women with obesity.

Menstrual Factors, Reproductive History, Hormone Use, and Urothelial Carcinoma Risk: A Prospective Study in the EPIC Cohort.

BACKGROUND: Urothelial carcinoma is the predominant (95%) bladder cancer subtype in industrialized nations. Animal and epidemiologic human studies suggest that hormonal factors may influence urothelial carcinoma risk. METHODS: We used an analytic cohort of 333,919 women from the European Prospective Investigation into Cancer and Nutrition Cohort. Associations between hormonal factors and incident urothelial carcinoma (overall and by tumor grade, tumor aggressiveness, and non-muscle-invasive urothelial carcinoma) risk were evaluated using Cox proportional hazards models. RESULTS: During a mean of 15 years of follow-up, 529 women developed urothelial carcinoma. In a model including number of full-term pregnancies (FTP), menopausal status, and menopausal hormone therapy (MHT), number of FTP was inversely associated with urothelial carcinoma risk (HR≥5vs1 = 0.48; 0.25-0.90; P trend in parous women = 0.010) and MHT use (compared with nonuse) was positively associated with urothelial carcinoma risk (HR = 1.27; 1.03-1.57), but no dose response by years of MHT use was observed. No modification of HRs by smoking status was observed. Finally, sensitivity analyses in never smokers showed similar HR patterns for the number of FTP, while no association between MHT use and urothelial carcinoma risk was observed. Association between MHT use and urothelial carcinoma risk remained significant only in current smokers. No heterogeneity of the risk estimations in the final model was observed by tumor aggressiveness or by tumor grade. A positive association between MTH use and non-muscle-invasive urothelial carcinoma risk was observed. CONCLUSIONS: Our results support that increasing the number of FTP may reduce urothelial carcinoma risk. IMPACT: More detailed studies on parity are needed to understand the possible effects of perinatal hormone changes in urothelial cells.

Association between lifestyle, dietary, reproductive, and anthropometric factors and circulating 27-hydroxycholesterol in EPIC-Heidelberg.

PURPOSE: Given that 27-hydroxycholesterol (27HC) is the first identified endogenous selective estrogen receptor modulator, the aim of this study was to investigate the extent to which dietary or lifestyle factors impact circulating 27HC concentrations in a large-scale setting. METHODS: This cross-sectional analysis included 1,036 women aged 35-65 years who served as controls in the European Prospective Investigation into Cancer and Nutrition (EPIC)-Heidelberg breast cancer case-control study. Circulating 27HC was quantified in serum using liquid chromatography/tandem mass spectrometry. Generalized linear models were used to investigate the association between 27HC concentrations and dietary habits, and lifestyle, reproductive, and anthropometric factors. RESULTS: Higher concentrations of 27HC were observed among postmenopausal relative to premenopausal women (geometric mean 200.5 vs. 188.4 nM, p = 0.03), whereas women reporting ever full-term pregnancy had lower concentrations of 27HC relative to never (191.4 vs. 198.6; p = 0.03). Significant trends were observed showing higher concentrations with relatively high levels of physical activity (ptrend = 0.03) and alcohol consumption (ptrend = 0.01), and women currently smoking at blood collection (ptrend < 0.01). Of the investigated dietary factors, starch (ptrend < 0.01) and thiamine (ptrend < 0.01) intakes were inversely associated with 27HC. Circulating lipid concentrations were positively associated with 27HC concentrations (all ptrend < 0.01). No significant associations were found between 27HC and factors including age at blood collection, body mass index, or use of hormone therapy or cholesterol-lowering medications. CONCLUSION: 27HC is of increasing interest for multiple chronic disease pathways. Despite significant associations found between circulating 27HC and dietary habits, reproductive factors, and modifiable lifestyle factors, circulating cholesterol, mostly low-density lipoprotein cholesterol, accounted for the majority of the variability in circulating 27HC.

Reproductive and Lifestyle Factors and Circulating sRANKL and OPG Concentrations in Women: Results from the EPIC Cohort.

BACKGROUND: Except for a documented increase in osteoprotegerin (OPG) concentrations with older age, data on determinants of soluble Receptor Activator of Nuclear Factor κB (sRANKL) and OPG concentrations in women are limited. We evaluated reproductive and lifestyle factors as potential sources of variation in circulating sRANKL and OPG concentrations in pre- and postmenopausal women. METHODS: This study includes 2,016 controls [n = 1,552 (76%) postmenopausal, n = 757 (38%) using postmenopausal hormone therapy (PMH)] from a breast cancer case-control study nested in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort. Serum sRANKL was measured using an ELISA and serum OPG using an electrochemiluminescent assay. Generalized linear models were used to evaluate associations between these analytes and reproductive and lifestyle factors. RESULTS: Older age at blood collection was associated with lower sRANKL concentrations in postmenopausal women (P trend ≤ 0.03) and higher OPG concentrations in all women (P trend ≤ 0.01). Longer duration of oral contraceptive use among premenopausal women and postmenopausal PMH users was associated with higher OPG (P trend ≤ 0.04). In postmenopausal non-PMH users, sRANKL concentrations were lower with longer duration of oral contraceptive use and current (vs. never) smoking (P ≤ 0.01). sRANKL concentrations were higher among women with higher BMI (P trend ≤ 0.01). The evaluated factors accounted for 12% of the variation in sRANKL concentrations and 21% of the variation in OPG concentrations. CONCLUSIONS: Circulating sRANKL and OPG concentrations are minimally impacted by hormone-related factors in pre- and postmenopausal women. IMPACT: This study suggests circulating concentrations of sRANKL and OPG are unlikely to be strongly modified by hormone-related reproductive and lifestyle factors.

Obesity as risk factor for subtypes of breast cancer: results from a prospective cohort study.

BACKGROUND: Earlier epidemiological studies indicate that associations between obesity and breast cancer risk may not only depend on menopausal status and use of exogenous hormones, but might also differ by tumor subtype. Here, we evaluated whether obesity is differentially associated with the risk of breast tumor subtypes, as defined by 6 immunohistochemical markers (ER, PR, HER2, Ki67, Bcl-2 and p53, separately and combined), in the prospective EPIC-Germany Study (n = 27,012). METHODS: Formalin-fixed and paraffin-embedded (FFPE) tumor tissues of 657 incident breast cancer cases were used for histopathological analyses. Associations between BMI and breast cancer risk across subtypes were evaluated by multivariable Cox regression models stratified by menopausal status and hormone therapy (HT) use. RESULTS: Among postmenopausal non-users of HT, higher BMI was significantly associated with an increased risk of less aggressive, i.e. ER+, PR+, HER2-, Ki67low, Bcl-2+ and p53- tumors (HR per 5 kg/m2: 1.44 [1.10, 1.90], p = 0.009), but not with risk of more aggressive tumor subtypes. Among postmenopausal users of HT, BMI was significantly inversely associated with less aggressive tumors (HR per 5 kg/m2: 0.68 [0.50, 0.94], p = 0.018). Finally, among pre- and perimenopausal women, Cox regression models did not reveal significant linear associations between BMI and risk of any tumor subtype, although analyses by BMI tertiles showed a significantly lower risk of less aggressive tumors for women in the highest tertile (HR: 0.55 [0.33, 0.93]). CONCLUSION: Overall, our results suggest that obesity is related to risk of breast tumors with lower aggressiveness, a finding that requires replication in larger-scale analyses of pooled prospective data.

Nonsteroidal anti-inflammatory drug use and breast cancer risk in a European prospective cohort study.

Experimental studies have shown a protective effect of nonsteroidal anti-inflammatory drugs (NSAIDs) on breast cancer development. However, results from epidemiological cohort studies are less consistent. Our objective was to assess the association between NSAID use and breast cancer risk within the European Prospective Investigation into Cancer and Nutrition (EPIC). EPIC is a prospective cohort study initiated in 1992 in 10 European countries. Self-reported information on NSAID use at baseline has been collected in five EPIC countries. Multivariable Cox regression models were used to estimate hazard ratios for the association of NSAID use with breast cancer incidence with adjustment for potential confounders. We also assessed effect modification by breast cancer risk factors and examined the associations within specific breast cancer subtypes. Among the 140,981 women included in the analysis, 7% were regularly using NSAIDs at baseline. During a median follow-up time period of 13 years, 7,379 incident breast cancer cases were diagnosed (816 in situ and 6,563 invasive). There were no statistically significant associations between NSAID use and breast cancer risk, overall and by subtypes. However, a statistically significant interaction was observed for invasive cases between NSAID use and ever use of menopausal hormonal therapy (MHT) among postmenopausal women [MHT users: HRNSAID use = 0.84 (0.73-0.96); non MHT users: HRNSAID use = 1.08 (0.93-1.25); pinteraction = 0.05]. Our results indicate potential effect modification of MHT use on the association between use of NSAIDs and breast cancer risk which deserves in-depth investigation in studies with accurate data on both NSAID and MHT use.

Tumor-associated autoantibodies as early detection markers for ovarian cancer? A prospective evaluation.

Immuno-proteomic screening has identified several tumor-associated autoantibodies (AAb) that may have diagnostic capacity for invasive epithelial ovarian cancer, with AAbs to P53 proteins and cancer-testis antigens (CTAGs) as prominent examples. However, the early detection potential of these AAbs has been insufficiently explored in prospective studies. We performed ELISA measurements of AAbs to CTAG1A, CTAG2, P53 and NUDT11 proteins, for 194 patients with ovarian cancer and 705 matched controls from the European EPIC cohort, using serum samples collected up to 36 months prior to diagnosis under usual care. CA125 was measured using electrochemo-luminiscence. Diagnostic discrimination statistics were calculated by strata of lead-time between blood collection and diagnosis. With lead times ≤6 months, ovarian cancer detection sensitivity at 0.98 specificity (SE98) varied from 0.19 [95% CI 0.08-0.40] for CTAG1A, CTAG2 and NUDT1 to 0.23 [0.10-0.44] for P53 (0.33 [0.11-0.68] for high-grade serous tumors). However, at longer lead-times, the ability of these AAb markers to distinguish future ovarian cancer cases from controls declined rapidly; at lead times >1 year, SE98 estimates were close to zero (all invasive cases, range: 0.01-0.11). Compared to CA125 alone, combined logistic regression scores of AAbs and CA125 did not improve detection sensitivity at equal level of specificity. The added value of these selected AAbs as markers for ovarian cancer beyond CA125 for early detection is therefore limited.