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.

Association of Mediterranean diet with survival after breast cancer diagnosis in women from nine European countries: results from the EPIC cohort study.

BACKGROUND: The Mediterranean diet has been associated with lower risk of breast cancer (BC) but evidence from prospective studies on the role of Mediterranean diet on BC survival remains sparse and conflicting. We aimed to investigate whether adherence to Mediterranean diet prior to diagnosis is associated with overall and BC-specific mortality. METHODS: A total of 13,270 incident breast cancer cases were identified from an initial sample of 318,686 women in 9 countries from the European Prospective Investigation into Cancer and Nutrition (EPIC) study. Adherence to Mediterranean diet was estimated through the adapted relative Mediterranean diet (arMED), a 16-point score that includes 8 key components of the Mediterranean diet and excludes alcohol. The degree of adherence to arMED was classified as low (score 0-5), medium (score 6-8), and high (score 9-16). Multivariable Cox proportional hazards models were used to analyze the association between the arMED score and overall mortality, and Fine-Gray competing risks models were applied for BC-specific mortality. RESULTS: After a mean follow-up of 8.6 years from diagnosis, 2340 women died, including 1475 from breast cancer. Among all BC survivors, low compared to medium adherence to arMED score was associated with a 13% higher risk of all-cause mortality (HR 1.13, 95%CI 1.01-1.26). High compared to medium adherence to arMED showed a non-statistically significant association (HR 0.94; 95% CI 0.84-1.05). With no statistically significant departures from linearity, on a continuous scale, a 3-unit increase in the arMED score was associated with an 8% reduced risk of overall mortality (HR3-unit 0.92, 95% CI: 0.87-0.97). This result sustained when restricted to postmenopausal women and was stronger among metastatic BC cases (HR3-unit 0.81, 95% CI: 0.72-0.91). CONCLUSIONS: Consuming a Mediterranean diet before BC diagnosis may improve long-term prognosis, particularly after menopause and in cases of metastatic breast cancer. Well-designed dietary interventions are needed to confirm these findings and define specific dietary recommendations.

Postdiagnosis circulating osteoprotegerin and TRAIL concentrations and survival and recurrence after a breast cancer diagnosis: results from the MARIE patient cohort.

BACKGROUND: Experimental studies suggest a role for osteoprotegerin (OPG) and tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) in mammary tumor development and progression. These biomarkers have been minimally investigated with respect to outcomes in breast cancer patients. METHODS: OPG and TRAIL were evaluated in blood samples collected from 2459 breast cancer patients enrolled in the MARIE study, a prospective population-based patient cohort, at median of 129 days after diagnosis. Participants were between ages 50 and 74 at diagnosis and recruited from 2002 to 2005 in two regions of Germany. Follow-up for recurrence and mortality was conducted through June 2015. Delayed-entry Cox proportional hazards regression was used to assess associations between OPG and TRAIL with all-cause and breast cancer-specific mortality, and recurrence, both overall and by tumor hormone receptor status. RESULTS: Median follow-up time was 11.7 years, with 485 deaths reported (277 breast cancer-specific). Higher OPG concentrations were associated with a higher risk of all-cause mortality (hazard ratio for 1-unit log2-transformed concentration (HRlog2) = 1.24 (95% confidence interval 1.03-1.49). Associations were observed in women diagnosed with ER-PR- tumors or discordant hormone receptor status (ER-PR-, HRlog2 = 1.93 (1.20-3.10); discordant ERPR, 1.70 (1.03-2.81)), but not for women with ER + PR + tumors (HRlog2 = 1.06 (0.83-1.35)). OPG was associated with a higher risk of recurrence among women with ER-PR- disease (HRlog2 = 2.18 (1.39-3.40)). We observed no associations between OPG and breast cancer-specific survival, or for TRAIL and any outcome. CONCLUSIONS: Higher circulating OPG may be a biomarker of a higher risk of poor outcome among women diagnosed with ER- breast cancer. Further mechanistic studies are warranted.

Dietary patterns related to biological mechanisms and survival after breast cancer diagnosis: results from a cohort study.

BACKGROUND: Inflammatory, insulin and oestrogenic pathways have been linked to breast cancer (BC). We aimed to examine the relationship between pre-diagnostic dietary patterns related to these mechanisms and BC survival. METHODS: The diabetes risk reduction diet (DRRD), inflammatory score of diet (ISD) and oestrogen-related dietary pattern (ERDP) were calculated using dietary data from the European Prospective Investigation into Cancer and Nutrition (EPIC) study. Cox proportional hazards models were used to assess associations between dietary patterns and overall mortality and competing risk models for associations with BC-specific mortality. RESULTS: We included 13,270 BC cases with a mean follow-up after diagnosis of 8.6 years, representing 2340 total deaths, including 1475 BC deaths. Higher adherence to the DRRD score was associated with lower overall mortality (HR1-SD 0.92; 95%CI 0.87-0.96). Greater adherence to pro-inflammatory diets was borderline associated with 6% higher mortality HR1-SD 1.06; 95%CI 1.00-1.12. No significant association with the oestrogen-related dietary pattern was observed. None of the dietary patterns were associated with BC-specific mortality. CONCLUSIONS: Greater adherence to an anti-diabetic and anti-inflammatory diet prior to diagnosis is associated with lower overall mortality among BC survivors. Long-term adherence to these dietary patterns could be a means to improve the prognosis of BC survivors.

Sweetened beverages are associated with a higher risk of differentiated thyroid cancer in the EPIC cohort: a dietary pattern approach.

BACKGROUND: Dietary pattern analysis has gained particular interest, because it reflects the complexity of dietary intake. The aim of this study was to explore the associations between a posteriori dietary patterns, derived using a data-driven approach, and the risk of differentiated thyroid cancer (TC) in Europe. METHODS: This investigation included 450,064 adults from the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort. Dietary intake was assessed using validated country-specific dietary questionnaires. A posteriori dietary patterns were computed using principal component analyses. Cox regression was used to calculate multivariable adjusted hazard ratios (HRs) and 95% confidence intervals (CIs). RESULTS: After a mean follow-up time of 14 years, 712 first differentiated TCs were diagnosed. In the fully adjusted model, a dietary pattern characterized by alcohol consumption (basically beer and wine) was negatively associated with differentiated TC risk (HRQ4vs.Q1 = 0.75; 95% CI:0.60-0.94, P-trend = 0.005), while a dietary pattern rich in sweetened beverages was positively associated with differentiated TC risk (HRQ4vs.Q1 = 1.26; 95% CI:0.99-1.61; P-trend = 0.07). The remaining 8 dietary patterns were not related to differentiated TC risk. The intake of sweetened beverages was positively associated with differentiated TC risk (HR100mL/d = 1.05; 95% CI:1.00-1.11), especially with papillary TC risk (HR100mL/d = 1.07; 95% CI:1.01-1.13). Similar results were observed with sugary and artificially sweetened beverages. CONCLUSIONS: The investigation of dietary patterns detected that the consumption of sweetened beverages was associated with a higher risk of differentiated thyroid cancer. Our results are in line with the general dietary recommendations of reducing the consumption of sweetened beverages.

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.

Adherence to mediterranean diet and the risk of differentiated thyroid cancer in a European cohort: The EPIC study.

Background: The Mediterranean diet (MD) has been proposed as a healthy diet with a potential to lower the incidence of several types of cancer, but there is no data regarding thyroid cancer (TC). We investigated the association between MD adherence, and its components, and the differentiated TC risk within the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort. Methods: Over 450,000 men and women from nine European countries were followed up for a mean of 14.1 years, during which 712 differentiated TC cases were identified. Adherence to MD was estimated using the relative MD (rMED) score, an 18-point scale including alcohol, and the adapted rMED (arMED) score, a 16-point scale excluding alcohol. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using Cox regression models adjusted for potential confounding factors. Results: Adherence to the arMED score was not associated with the risk of differentiated TC (HRhigh vs. low adherence = 0.94, 95% CI: 0.70-1.25; p-trend 0.27), while a suggestive, but non-statistically significant inverse relationship was observed with rMED (HRhigh vs. low adherence = 0.88, 95% CI: 0.68-1.14; p-trend 0.17). Low meat (HRlow vs. high meat intake = 0.81, 95% CI: 0.67-0.99; p-trend = 0.04) and moderate alcohol (HRmoderate vs. non-moderate intake = 0.88, 95% CI: 0.75-1.03) intake were related with lower differentiated TC risk. Conclusions: Our study shows that a high adherence to MD is not strongly related to differentiated TC risk, although further research is required to confirm the impact of MD and, especially, meat intake in TC risk.

Inflammatory potential of the diet and association with risk of differentiated thyroid cancer in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort.

PURPOSE: Chronic inflammation is thought to initiate or promote differentiated thyroid cancer (DTC) and previous studies have shown that diet can modulate this inflammatory process. We aimed to evaluate the association of several dietary scores reflecting the inflammatory potential of the diet with DTC risk. METHODS: Within the EPIC cohort, 450,063 participants were followed during a mean period of 14 years, and 712 newly incident DTC cases were identified. Associations between four dietary inflammatory scores [the dietary inflammatory index (DII®) and two energy-adjusted derivatives (the E-DIIr and the E-DIId), and the Inflammatory Score of the Diet (ISD)] and DTC risk were evaluated in the EPIC cohort using multivariable Cox regression models. RESULTS: Positive associations were observed between DTC risk and the DIIs (HR for 1 SD increase in DII: 1.11, 95%CI: 1.01, 1.23, similar results for its derivatives), but not with the ISD (HR for 1 SD increase: 1.04, 95% CI 0.93, 1.16). CONCLUSION: Diet-associated inflammation, as estimated by the DII and its derivatives, was weakly positively associated with DTC risk in a European adult population. These results suggesting that diet-associated inflammation acts in the etiology of DTC need to be validated in independent studies.

Parental occupational exposures in wood-related jobs and risk of testicular germ cell tumours in offspring in NORD-TEST a registry-based case-control study in Finland, Norway, and Sweden.

OBJECTIVE: We assessed the association between parental prenatal exposures in wood-related jobs and risk of testicular germ cell tumours (TGCT) in offspring. METHODS: NORD-TEST, a registry-based case-control study in Sweden, Finland and Norway, included 8112 TGCT cases diagnosed at ages 14-49 years between 1978 and 2012 with no history of prior cancer, and up to four controls matched to each case on year and country of birth. Parents of cases and controls were identified via linkages with the population registries and their occupational information was retrieved from censuses. The Nordic Occupational Cancer Study Job-Exposure Matrix was used to assign occupational exposures to each parent. Logistic regression models were used to estimate odds ratios (OR) and 95% confidence intervals (CI). RESULTS: Maternal wood-related job was not associated with the risk of TGCT in offspring (OR 1.08, CI 0.55-2.14), while paternal wood-related job was associated with a decreased risk of TGCT in offspring (OR 0.85, CI 0.75-0.96). None of the specific wood-related jobs, such as upholsterers, sawyers, or construction carpenters, were significantly associated with a risk of TGCT. Only exception was observed in a sensitivity analysis which showed an increased risk in the small group of sons of fathers working as 'cabinetmakers and joiners' the year before conception (OR of 2.06, CI 1.00-4.25). CONCLUSION: This large-scale NORD-TEST analysis provided no evidence of an association between parental prenatal exposures in wood-related jobs and TGCT in sons.

Are Circulating Immune Cells a Determinant of Pancreatic Cancer Risk? A Prospective Study Using Epigenetic Cell Count Measures.

BACKGROUND: Evidence is accumulating that immune cells play a prominent role in pancreatic cancer etiology but prospective investigations are missing. METHODS: We conducted a nested case-control study within the European Prospective Investigation into Cancer and Nutrition (EPIC) study with 502 pairs of incident pancreatic cancer cases and matched controls. Relative counts of circulating immune cells (neutrophils and lymphocyte sublineages: total CD3+, CD8+, CD4+, and FOXP3+ regulatory T cells (Tregs) relative to nucleated cells, (white blood cells) were measured by qRT-PCR. ORs with 95% confidence intervals were estimated using logistic regressions, modeling relative counts of immune cells on a continuous scale. RESULTS: Neither relative counts of immune cell types taken individually, nor mutually adjusted for each other were associated with pancreatic cancer risks. However, in subgroup analyses by strata of lag-time, higher relative counts of Tregs and lower relative counts of CD8+ were significantly associated with an increased pancreatic cancer risks in participants diagnosed within the first 5 years of follow-up. CONCLUSIONS: These results might reflect reverse causation, due to higher relative counts of Tregs and lower counts of CD8+ cells among individuals with more advanced stages of latent pancreatic cancer, who are closer to the point of developing clinical manifest disease. IMPACT: We have shown, for the first time, that increased relative counts of regulatory T cells and lower relative counts of CD8+, cytotoxic T cells may be associated with pancreatic cancer risk or relatively late-stage tumor development.See related commentary by Michaud and Kelsey, p. 2176.

Chronic Low-Dose Exposure to Xenoestrogen Ambient Air Pollutants and Breast Cancer Risk: XENAIR Protocol for a Case-Control Study Nested Within the French E3N Cohort.

BACKGROUND: Breast cancer is the most frequent cancer in women in industrialized countries. Lifestyle and environmental factors, particularly endocrine-disrupting pollutants, have been suggested to play a role in breast cancer risk. Current epidemiological studies, although not fully consistent, suggest a positive association of breast cancer risk with exposure to several International Agency for Research on Cancer Group 1 air-pollutant carcinogens, such as particulate matter, polychlorinated biphenyls (PCB), dioxins, Benzo[a]pyrene (BaP), and cadmium. However, epidemiological studies remain scarce and inconsistent. It has been proposed that the menopausal status could modify the relationship between pollutants and breast cancer and that the association varies with hormone receptor status. OBJECTIVE: The XENAIR project will investigate the association of breast cancer risk (overall and by hormone receptor status) with chronic exposure to selected air pollutants, including particulate matter, nitrogen dioxide (NO2), ozone (O3), BaP, dioxins, PCB-153, and cadmium. METHODS: Our research is based on a case-control study nested within the French national E3N cohort of 5222 invasive breast cancer cases identified during follow-up from 1990 to 2011, and 5222 matched controls. A questionnaire was sent to all participants to collect their lifetime residential addresses and information on indoor pollution. We will assess these exposures using complementary models of land-use regression, atmospheric dispersion, and regional chemistry-transport (CHIMERE) models, via a Geographic Information System. Associations with breast cancer risk will be modeled using conditional logistic regression models. We will also study the impact of exposure on DNA methylation and interactions with genetic polymorphisms. Appropriate statistical methods, including Bayesian modeling, principal component analysis, and cluster analysis, will be used to assess the impact of multipollutant exposure. The fraction of breast cancer cases attributable to air pollution will be estimated. RESULTS: The XENAIR project will contribute to current knowledge on the health effects of air pollution and identify and understand environmental modifiable risk factors related to breast cancer risk. CONCLUSIONS: The results will provide relevant evidence to governments and policy-makers to improve effective public health prevention strategies on air pollution. The XENAIR dataset can be used in future efforts to study the effects of exposure to air pollution associated with other chronic conditions. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/15167.

Serologic markers of Chlamydia trachomatis and other sexually transmitted infections and subsequent ovarian cancer risk: Results from the EPIC cohort.

A substantial proportion of epithelial ovarian cancer (EOC) arises in the fallopian tube and other epithelia of the upper genital tract; these epithelia may incur damage and neoplastic transformation after sexually transmitted infections (STI) and pelvic inflammatory disease. We investigated the hypothesis that past STI infection, particularly Chlamydia trachomatis, is associated with higher EOC risk in a nested case-control study within the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort including 791 cases and 1669 matched controls. Serum antibodies against C. trachomatis, Mycoplasma genitalium, herpes simplex virus type 2 (HSV-2) and human papillomavirus (HPV) 16, 18 and 45 were assessed using multiplex fluorescent bead-based serology. Conditional logistic regression was used to estimate relative risks (RR) and 95% confidence intervals (CI) comparing women with positive vs. negative serology. A total of 40% of the study population was seropositive to at least one STI. Positive serology to C. trachomatis Pgp3 antibodies was not associated with EOC risk overall, but with higher risk of the mucinous histotype (RR = 2.30 [95% CI = 1.22-4.32]). Positive serology for chlamydia heat shock protein 60 (cHSP60-1) was associated with higher risk of EOC overall (1.36 [1.13-1.64]) and with the serous subtype (1.44 [1.12-1.85]). None of the other evaluated STIs were associated with EOC risk overall; however, HSV-2 was associated with higher risk of endometrioid EOC (2.35 [1.24-4.43]). The findings of our study suggest a potential role of C. trachomatis in the carcinogenesis of serous and mucinous EOC, while HSV-2 might promote the development of endometrioid disease.

Circulating 27-hydroxycholesterol and breast cancer tissue expression of CYP27A1, CYP7B1, LXR-ß, and ERß: results from the EPIC-Heidelberg cohort.

BACKGROUND: Experimental and epidemiological studies demonstrate a role for 27-hydroxycholesterol (27HC) in breast cancer development, though results are conflicting. Cholesterol 27-hydroxylase (CYP27A1) and oxysterol 7-alpha-hydroxylase (CYP7B1) regulate 27HC concentrations, while differential expression of the liver X receptor (LXR) and estrogen receptor beta (ERß) may impact the association between 27HC and breast cancer risk. METHODS: We evaluated correlates of tumor tissue expression of CYP27A1, CYP7B1, LXR-ß, and ERß and the association between circulating prediagnostic 27HC concentrations and breast cancer risk by marker expression in a nested case-control study within the European Prospective Investigation into Cancer and Nutrition (EPIC)-Heidelberg cohort including 287 breast cancer cases with tumor tissue available. Tumor protein expression was evaluated using immunohistochemistry, and serum 27HC concentrations quantified using liquid chromatography-mass spectrometry. Conditional logistic regression models were used to estimate odds ratios (ORs) and 95% confidence intervals (CIs). RESULTS: A higher proportion of CYP7B1-positive cases were progesterone receptor (PR)-positive, relative to CYP7B1-negative cases, whereas a higher proportion of ERß-positive cases were Bcl-2 low, relative to ERß-negative cases. No differences in tumor tissue marker positivity were observed by reproductive and lifestyle factors. We observed limited evidence of heterogeneity in associations between circulating 27HC and breast cancer risk by tumor tissue expression of CYP27A1, CYP7B1, LXR-ß, and ERß, with the exception of statistically significant heterogeneity by LXR-ß status in the subgroup of women perimenopausal at blood collection (p = 0.02). CONCLUSION: This exploratory study suggests limited associations between tumor marker status and epidemiologic or breast cancer characteristics. Furthermore, the association between circulating 27HC and breast cancer risk may not vary by tumor expression of CYP27A1, CYP7B1, LXR-ß, or ERß.

Circulating Immune Cell Composition and Cancer Risk: A Prospective Study Using Epigenetic Cell Count Measures.

Although ample evidence indicates that immune cell homeostasis is an important prognostic outcome determinant in patients with cancer, few studies have examined whether it also determines cancer risk among initially healthy individuals. We performed a case-cohort study including incident cases of breast (n = 207), colorectal (n = 111), lung (n = 70), and prostate (n = 201) cancer as well as a subcohort (n = 465) within the European Prospective Investigation into Cancer and Nutrition-Heidelberg cohort. Relative counts of neutrophils, monocytes, and lymphocyte sublineages were measured by qRT-PCR. HRs and 95% confidence intervals were used to measure the associations between relative counts of immune cell and cancer risks. When relative counts of immune cell types were taken individually, a significant positive association was observed between relative counts of FOXP3+ regulatory T cells (Tregs) and lung cancer risk, and significant inverse associations were observed between relative CD8+ counts and risks of lung and breast cancer (overall and ER+ subtype). Multivariable models with mutual adjustments across immune markers showed further significant positive associations between higher relative FOXP3+ T-cell counts and increased risks of colorectal and breast cancer (overall and ER- subtype). No associations were found between immune cell composition and prostate cancer risk. These results affirm the relevance of elevated FOXP3+ Tregs and lower levels of cytotoxic (CD8+) T cells as risk factors for tumor development. SIGNIFICANCE: This epidemiologic study supports a role for both regulatory and cytotoxic T cells in determining cancer risk among healthy individuals.See related commentary by Song and Tworoger, p. 1801.

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.

Circulating 27-Hydroxycholesterol and Breast Cancer Risk: Results From the EPIC-Heidelberg Cohort.

BACKGROUND: 27-hydroxycholesterol (27HC) was the first identified endogenous selective estrogen receptor modulator (SERM); 27HC promoted growth and metastasis in experimental models of estrogen receptor-positive mammary cancer. There are no data on prediagnosis circulating 27HC and breast cancer risk in women. METHODS: We conducted a nested case-control study in the well-characterized Heidelberg, Germany, cohort of the European Investigation into Cancer and Nutrition (EPIC) including 530 incident invasive breast cancer cases, each matched to up to two control participants (n = 1036). Serum 27HC was analyzed by liquid chromatography-mass spectrometry (LC-MS) in blood samples collected at study recruitment. Multivariable conditional logistic regression models were used to quantify the association between circulating 27HC and breast cancer risk overall, by tumor hormone receptor status (ie estrogen and progesterone receptors), and by menopausal status at blood collection. All statistical tests were two-sided. RESULTS: 27HC was not associated with breast cancer risk overall (relative risk [RR]Quartile4vsQuartile1 [Q4vsQ1] = 0.90, 95% confidence interval [CI] = 0.66 to 1.22). The association between 27HC and breast cancer risk differed by menopausal status at blood collection (Phet = .02), but not by age at diagnosis (Phet = .78). Among women who were postmenopausal at blood collection, higher serum 27HC levels were associated with lower breast cancer risk (RRQ4vsQ1 = 0.56, 95% CI = 0.36 to 0.87). We observed no association between 27HC and breast cancer risk (RRQ4vsQ1 = 1.33, 95% CI = 0.75 to 2.38) among women who were premenopausal at blood collection. CONCLUSIONS: In this first prospective study, higher circulating 27HC was associated with lower risk of breast cancer in postmenopausal women. Identification of the first endogenous SERM associated with reduced risk of invasive breast cancer in postmenopausal women may offer novel avenues for breast cancer prevention strategies.

Parental occupational exposure to solvents and heavy metals and risk of developing testicular germ cell tumors in sons (NORD-TEST Denmark).

Objective The present study aims to assess if parental occupational exposure to solvents or heavy metals is associated with risk of testicular germ cell tumors (TGCT) in sons in Denmark. Methods The NORD-TEST Denmark included 3421 cases diagnosed with TGCT at ages 14-49 years in Denmark between 1981 and 2014. Controls (N=14 024) selected from the central population registry were matched to cases on birth year. The Danish Supplementary Pension Fund provided parental occupational information. A job-exposure matrix was used to assign exposures, and conditional logistic regression models were used to estimate odds ratios (OR) and 95% confidence intervals (CI). Results The overall analyses showed no significant associations except for paternal exposure to a sub-group of "heavy metal(s) and solvent(s)" (OR 1.50, 95% CI 1.01-2.24). Most fathers in this category had worked in wood related jobs and were assigned exposure to chromium VI and toluene. Other sub-group analyses suggested that maternal exposure to aromatic hydrocarbon were associated with TGCT risk, in sons born in 1970-1979, and to heavy metals (chromium, iron and nickel) in sons born in 1980-1998. Conclusion NORD-TEST Denmark provides no strong support for an association between parental exposures to solvents or heavy metals and TGCT in sons, and only weak support for an association between paternal exposure to chromium and toluene and TGCT risk in sons.

Reproducibility of serum oxysterols and lanosterol among postmenopausal women: Results from EPIC-Heidelberg.

BACKGROUND: Circulating oxysterols have been proposed as biological markers of disease risk. However, within-person reproducibility of circulating oxysterols over time is not well established. METHODS: We evaluated the one-year reproducibility of 11 oxysterols and lanosterol among 30 postmenopausal women with repeat blood samples in the European Prospective Investigation into Cancer and Nutrition (EPIC) - Heidelberg, Germany cohort. Liquid chromatography-mass spectrometry (LC/MS) was performed to quantify serum concentrations of 22R-hydroxycholesterol, 25-hydroxycholesterol, 24S-hydroxycholesterol, 27-hydroxycholesterol, 22S-hydroxycholeterol, 24,25-epoxycholesterol, 5α,6ß-dihydroxycholestanol, 7α-hydroxycholesterol, 5ß,6ß-epoxycholesterol, 5α,6α-epoxycholesterol, 24-dihydrolanosterol, and lanosterol. We evaluated Spearman correlations and intraclass correlation coefficients (ICCs) between quantifiable concentrations measured in repeat samples taken one-year apart to estimate within-person reproducibility. RESULTS: Spearman correlations (ICCs) over one year ranged from 0 (ICC=0.10) for 5ß,6ß-epoxycholesterol and 0.10 (ICC=0.20) for 5α,6α-epoxycholesterol, representing low within-person stability, to 0.81 (ICC=0.75) for 27-hydroxycholesterol and 0.86 (ICC=0.91) for 24S-hydroxycholesterol, representing relatively high within-person stability. Correlations between oxysterols and lanosterol ranged from 0.01 between 24S-hydroxycholesterol and lanosterol to 0.70 between 5α,6α-epoxycholesterol and 5ß,6ß-epoxycholesterol. CONCLUSIONS: Our results demonstrate that for 27-hydroxycholesterol, 24S-hydroxycholesterol, 25-hydroxycholesterol, 7α-hydroxycholesterol and lanosterol, a single serum measurement can reliably estimate average levels over a one-year period. Circulating oxysterols are of increasing interest in epidemiologic studies of chronic disease risk including cancer and cardiovascular disease. Our data suggest that within-person stability of oxysterols differs depending on the individual oxysterol evaluated. We identified four oxysterols and lanosterol as stable over time to inform the use of circulating oxysterols in epidemiologic studies.

Ovarian cancer early detection by circulating CA125 in the context of anti-CA125 autoantibody levels: Results from the EPIC cohort.

CA125 is the best ovarian cancer early detection marker to date; however, sensitivity is limited and complementary markers are required to improve discrimination between ovarian cancer cases and non-cases. Anti-CA125 autoantibodies are observed in circulation. Our objective was to evaluate whether these antibodies (1) can serve as early detection markers, providing evidence of an immune response to a developing tumor, and (2) modify the discriminatory capacity of CA125 by either masking CA125 levels (resulting in lower discrimination) or acting synergistically to improve discrimination between cases and non-cases. We investigated these objectives using a nested case-control study within the European Prospective Investigation into Cancer and Nutrition cohort (EPIC) including 250 cases diagnosed within 4 years of blood collection and up to four matched controls. Circulating CA125 antigen and antibody levels were quantified using an electrochemiluminescence assay. Adjusted areas under the curve (aAUCs) by 2-year lag-time intervals were calculated using conditional logistic regression calibrated toward the absolute risk estimates from a pre-existing epidemiological risk model as an offset-variable. Anti-CA125 levels alone did not discriminate cases from controls. For cases diagnosed <2 years after blood collection, discrimination by CA125 antigen was suggestively higher with higher anti-CA125 levels (aAUC, highest antibody tertile: 0.84 [0.76-0.92]; lowest tertile: 0.76 [0.67-0.86]; phet = 0.06). We provide the first evidence of potentially synergistic discrimination effects of CA125 and anti-CA125 antibodies in ovarian early detection. If these findings are replicated, evaluating CA125 in the context of its antibody may improve ovarian cancer early detection.