Association Of Breast Cancer Risk Research Articles

Mammographic Texture versus Conventional Cumulus Measure of Density in Breast Cancer Risk Prediction: A Literature Review.

Mammographic textures show promise as breast cancer risk predictors, distinct from mammographic density. Yet, there is a lack of comprehensive evidence to determine the relative strengths as risk predictor of textures and density and the reliability of texture-based measures. We searched the PubMed database for research published up to November 2023, which assessed breast cancer risk associations [odds ratios (OR)] with texture-based measures and percent mammographic density (PMD), and their discrimination [area under the receiver operating characteristics curve (AUC)], using same datasets. Of 11 publications, for textures, six found stronger associations (P < 0.05) with 11% to 508% increases on the log scale by study, and four found weaker associations (P < 0.05) with 14% to 100% decreases, compared with PMD. Risk associations remained significant when fitting textures and PMD together. Eleven of 17 publications found greater AUCs for textures than PMD (P < 0.05); increases were 0.04 to 0.25 by study. Discrimination from PMD and these textures jointly was significantly higher than from PMD alone (P < 0.05). Therefore, different textures could capture distinct breast cancer risk information, partially independent of mammographic density, suggesting their joint role in breast cancer risk prediction. Some textures could outperform mammographic density for predicting breast cancer risk. However, obtaining reliable texture-based measures necessitates addressing various issues. Collaboration of researchers from diverse fields could be beneficial for advancing this complex field.

Abstract 6119: Association of genetic African ancestry and triple-negative breast cancer risk: Findings from the African-ancestry breast cancer genetics consortium

Abstract Triple-negative breast cancer (TNBC) is an aggressive breast cancer subtype that lacks target treatments. It has been reported that African-American women have a higher incidence of TNBC and are diagnosed at an earlier age than women of European ancestry. This disparity may be attributed to both genetic and non-genetic risk factors that are associated with the African ancestry. In this study, we investigated whether genotype-derived African ancestry might be related to an elevated risk of TNBC, with adjustments for several known genetic and non-genetic risk factors. Included in the study are self-reported Black breast cancer patients diagnosed with TNBC (n =2,292) or estrogen receptor (ER)-positive cancer (n =7,863) and 9,324 controls included in the African-ancestry Breast Cancer Genetics (AABCG) Consortium. We estimated the global ancestry by Admixture and the local ancestry by FLARE, using reference of the European- and African-ancestry samples from the 1000 Genome Project. Odds ratios (OR) and 95% confidence interval (CI) per ten percent increase of the global African ancestry proportion were estimated using logistic regressions comparing TNBC with controls (case-control analyses) or with ER-positive cases (case-case analyses), adjusted for age. Similar analyses were conducted for the local African ancestry proportion at each of the 12 genomic regions that were identified in AABCG in relation to TNBC risk. Results for each participating study were meta-analyzed using fixed or random effect models. We further adjusted for non-genetic risk factors including body mass index (BMI), number of live births, breastfeeding, and menopausal status. A polygenic risk score (PRS) was constructed using 13 independent risk variants at the 12 TNBC risk loci. The PRS was additionally adjusted to investigate whether these risk variants mediated the association of African ancestry with TNBC risk. No significant association was observed between TNBC risk and global African ancestry proportion (OR: 1.03, 95% CI: 0.98-1.08) in case-control comparisons. Compared with ER-positive cases, however, TNBC cases had a higher global African ancestry, resulted in an OR of 1.09 (95% CI: 1.04, 1.13, P =5.35×10-5). A similar association was observed with additional adjustment for non-genetic risk factors, with an OR of 1.08 (95% CI: 1.03, 1.12, P =0.003). Similar patterns were also found for local ancestry proportion at six of the 12 TNBC risk loci (P &amp;lt;0.05). Further adjustment for the PRS attenuated the association between global ancestry and a TNBC diagnosis in case-case comparisons (OR: 1.05, 95% CI: 1.01, 1.10, P =0.013). Our study suggests that women with a higher African ancestry are more likely to be diagnosed with a TNBC than ER-positive breast cancer and genetic factors identified to date partially explain this association. Citation Format: Guochong Jia, Lili Liu, Julie R. Palmer, Christopher A. Haiman, Wei Zheng. Association of genetic African ancestry and triple-negative breast cancer risk: Findings from the African-ancestry breast cancer genetics consortium [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6119.

The Impact of microRNA SNPs on Breast Cancer: Potential Biomarkers for Disease Detection.

Breast cancer is considered a significant health concern worldwide, with genetic predisposition playing a critical role in its etiology. Single nucleotide polymorphisms (SNPs), particularly those within the 3' untranslated regions (3'UTRs) of target genes, are emerging as key factors in breast cancer susceptibility. Specifically, miRNAs have been recognized as possible novel approach for biomarkers discovery for both prognosis and diagnosis due to their direct association with cancer progression. Regional disparities in breast cancer incidence underscore the need for precise interventions, considering socio-cultural and economic factors. This review explores into the differential effects of SNP-miRNA interactions on breast cancer risk, emphasizing both risk-enhancing and protective associations across diverse populations. Furthermore, it explores the clinical implications of these findings, highlighting the potential of personalized approaches in breast cancer management. Additionally, it reviews the evolving therapeutic prospect of microRNAs (miRNAs), extending beyond cancer therapeutics to encompass various diseases, indicative of their versatility as therapeutic agents.

Маммографическая плотность и риск рака молочной железы (обзор литературы)

Abstract. Breast cancer is a significant global public health problem and one of the most common cancers among women. Mammography is the main method for screening and diagnosing breast cancer, and it is important to understand the relation of mammographic density and the risk of developing this disease. In this research we review existing works on this issue and analyze the available data to assess the association of mammographic density and breast cancer risk. Our results confirm a significant association of mammographic density and breast cancer risk, highlighting the importance of this parameter in screening and predicting the development of breast cancer. Mammographic density has clinical significance in breast cancer screening and prognosis and can be used to determine an individual’s risk of developing breast cancer and make decisions about further testing and treatment. Future research should be aimed at elucidating the mechanisms underlying this association, as well as developing innovative screening methods that incorporate mammographic density as a prognostic factor.

Breast cancer risk association with postmenopausal hormone therapy: Health Insurance Database in South Korea-based cohort study.

Although many physicians have been concerned that the menopausal hormones used currently in clinical practice may affect the risk of breast cancer, there are currently few informative updated studies about the associations between menopausal hormone therapy (MHT) and the risk of breast cancer. This study aims to evaluate the association between the risk of breast cancer and MHT using the National Health Insurance Database in South Korea (HISK) cohort between 2002 and 2019 retrospectively. Postmenopausal women over 40 years of age from 2003 to 2011 were selected as the subject population, and their follow-up data were collected until 2019. We analyzed the risk and mortality of breast cancer according to the type of MHT received, namely, tibolone, combined estrogen plus progestin by manufacturer (CEPM), oral estrogen, combined estrogen plus progestin by physician (CEPP), or topical estrogen. The risk of breast cancer increased in the CEPM group [hazard ratio (HR) 1.439, 95% CI 1.374-1.507, P-value < .001] in comparison with the non-MHT group. However, no significant associations were found between the use of tibolone, oral estrogen, CEPP, or topical estrogen and breast cancer risk in comparison with the non-MHT group (HR 0.968, 95% CI 0.925-1.012; HR 1.002, 95% CI 0.929-1.081; HR 0.929, 95% CI 0.75-1.15; HR 1.139, 95% CI 0.809-1.603). The mortality rate from breast cancer is lower in the MHT group in comparison with the non-MHT group, indicating that significant associations were found for tibolone, CEPM, and oral estrogen (HR 0.504, 95% CI 0.432-0.588; HR 0.429, 95% CI 0.352-0.522; HR 0.453 95% CI 0.349-0.588, P-value < .001). This study suggests that the risk of breast cancer is increased by drugs in the CEPM group but not by tibolone, oral estrogen, CEPP, or topical estrogen. The mortality rate from breast cancer is lower with MHT (tibolone, CEPM, oral estrogen) than without MHT.

Mosquito control exposures and breast cancer risk: analysis of 1071 cases and 2096 controls from the Ghana Breast Health Study

Epidemiologic data on insecticide exposures and breast cancer risk are inconclusive and mostly from high-income countries. Using data from 1071 invasive pathologically confirmed breast cancer cases and 2096 controls from the Ghana Breast Health Study conducted from 2013 to 2015, we investigated associations with mosquito control products to reduce the spread of mosquito-borne diseases, such as malaria. These mosquito control products were insecticide-treated nets, mosquito coils, repellent room sprays, and skin creams for personal protection against mosquitos. Multivariable and polytomous logistic regression models were used to estimate odds ratios (ORadj) and 95% confidence intervals (CI) with breast cancer risk-adjusted for potential confounders and known risk factors. Among controls, the reported use of mosquito control products were mosquito coils (65%), followed by insecticide-treated nets (56%), repellent room sprays (53%), and repellent skin creams (15%). Compared to a referent group of participants unexposed to mosquito control products, there was no significant association between breast cancer risk and mosquito coils. There was an association in breast cancer risk with reported use of insecticide-treated nets; however, that association was weak and not statistically significant. Participants who reported using repellent sprays were at elevated risks compared to women who did not use any mosquito control products, even after adjustment for all other mosquito control products (OR = 1.42, 95% CI=1.15–1.75). We had limited power to detect an association with repellent skin creams. Although only a few participants reported using repellent room sprays weekly/daily or < month-monthly, no trends were evident with increased frequency of use of repellent sprays, and there was no statistical evidence of heterogeneity by estrogen receptor (ER) status (p-het > 0.25). Our analysis was limited when determining if an association existed with repellent skin creams; therefore, we cannot conclude an association. We found limited evidence of risk associations with widely used mosquito coils and insecticide-treated nets, which are reassuring given their importance for malaria prevention. Our findings regarding specific breast cancer risk associations, specifically those observed between repellent sprays, require further study.

Association of CYP1A2 Gene rs17861162 Polymorphism and Breast Cancer Risk in Iranian Women: A Case-control Study

Background: Breast cancer is the most commonly diagnosed malignant neoplasm among women worldwide. The significance of gene polymorphism in cytochrome P450 (CYP) 1A2 (CYP3A4) in cancer development is generally acknowledged. Objectives: The objective of this study was to investigate the possible association between the rs17861162 polymorphism of the CYP1A2 gene and vulnerability to breast cancer among women of Iranian heritage. Methods: In the current study, a cohort comprising 100 women who were diagnosed with breast cancer was identified as the case group in a case-control inquiry. Another cohort of 100 women in good health and residing in East Azerbaijan province, with similar age and ethnicity attributes to the individuals in the case group, were selected as the control group. The genomic DNA was obtained from leukocytes isolated from peripheral blood through a phenol-chloroform extraction method. The genotyping experiment was performed using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique. Results: The findings of this study indicated that genotypic distribution among individuals diagnosed with breast cancer was 54% CC, 37% CG, and 9% GG. On the other hand, the healthy control group exhibited a distribution of 69% CC, 27% CG, and 2% GG. The statistical analysis revealed notable variations in the genotype and allele frequencies of the rs17861162 polymorphism in the CYP1A2 gene between people diagnosed with breast cancer and healthy control subjects (P&gt;0.05). Conclusions: The results of our study indicated a significant association between breast cancer and the rs17861162 polymorphism in the CYP1A2 gene among Iranian women. In order to gain a comprehensive understanding of the specific ramifications of this polymorphism concerning breast cancer prognosis, diagnosis, and risk, it is imperative to perform additional research that spans a wide range of ethnic and geographical populations.

Epigenetic germline variants predict cancer prognosis and risk and distribute uniquely in topologically associating domains

Background: Methylation quantitative trait loci (meQTLs) associate with different levels of local DNA methylation in cancers. Here, we investigated whether the distribution of cancer meQTLs reflected functional organization of the genome in the form of chromatin topologically associated domains (TADs) and evaluated whether cancer meQTLs near known driver genes have the potential to influence cancer risk or progression. Methods: Published cancer meQTLs were analyzed according to their location in transcriptionally active or inactive TADs and TAD boundary regions. Cancer meQTLs near known cancer genes were analyzed for association with cancer risk in the UKBioBank and prognosis in The Cancer Genome Atlas (TCGA). Results: In TAD boundary regions, the density of cancer meQTLs was higher near inactive TADs. Furthermore, we observed an enrichment of cancer meQTLs in active TADs near tumor suppressors, whereas there was a depletion of such meQTLs near oncogenes. Several meQTLs were associated with cancer risk in the UKBioBank, and we were able to reproduce breast cancer risk associations in the DRIVE cohort. Survival analysis in TCGA implicated a number of meQTLs in 13 tumor types. In 10 of these, polygenic cancer meQTL scores were associated with increased hazard in a CoxPH analysis. Risk and survival-associated meQTLs tended to affect cancer genes involved in DNA damage repair and cellular adhesion and reproduced cancer-specific associations reported in prior literature. Conclusions: This study provides evidence that genetic variants that influence local DNA methylation are affected by chromatin structure and can impact tumor evolution.

Refining the genetic risk of breast cancer with rare haplotypes and pattern mining.

Hundreds of common variants have been found to confer small but significant differences in breast cancer risk, supporting the widely accepted polygenic model of inherited predisposition. Using a novel closed-pattern mining algorithm, we provide evidence that rare haplotypes may refine the association of breast cancer risk with common germline alleles. Our method, called Chromosome Overlap, consists in iteratively pairing chromosomes from affected individuals and looking for noncontiguous patterns of shared alleles. We applied Chromosome Overlap to haplotypes of genotyped SNPs from female breast cancer cases from the UK Biobank at four loci containing common breast cancer-risk SNPs. We found two rare (frequency <0.1%) haplotypes bearing a GWAS hit at 11q13 (hazard ratio = 4.21 and 16.7) which replicated in an independent, European ancestry population at P < 0.05, and another at 22q12 (frequency <0.2%, hazard ratio = 2.58) which expanded the risk pool to noncarriers of a GWAS hit. These results suggest that rare haplotypes (or mutations) may underlie the "synthetic association" of breast cancer risk with at least some common variants.

Associations of height, body mass index, and weight gain with breast cancer risk in carriers of a pathogenic variant in BRCA1 or BRCA2: the BRCA1 and BRCA2 Cohort Consortium

IntroductionHeight, body mass index (BMI), and weight gain are associated with breast cancer risk in the general population. It is unclear whether these associations also exist for carriers of pathogenic variants in the BRCA1 or BRCA2 genes.Patients and methodsAn international pooled cohort of 8091 BRCA1/2 variant carriers was used for retrospective and prospective analyses separately for premenopausal and postmenopausal women. Cox regression was used to estimate breast cancer risk associations with height, BMI, and weight change.ResultsIn the retrospective analysis, taller height was associated with risk of premenopausal breast cancer for BRCA2 variant carriers (HR 1.20 per 10 cm increase, 95% CI 1.04–1.38). Higher young-adult BMI was associated with lower premenopausal breast cancer risk for both BRCA1 (HR 0.75 per 5 kg/m2, 95% CI 0.66–0.84) and BRCA2 (HR 0.76, 95% CI 0.65–0.89) variant carriers in the retrospective analysis, with consistent, though not statistically significant, findings from the prospective analysis. In the prospective analysis, higher BMI and adult weight gain were associated with higher postmenopausal breast cancer risk for BRCA1 carriers (HR 1.20 per 5 kg/m2, 95% CI 1.02–1.42; and HR 1.10 per 5 kg weight gain, 95% CI 1.01–1.19, respectively).ConclusionAnthropometric measures are associated with breast cancer risk for BRCA1 and BRCA2 variant carriers, with relative risk estimates that are generally consistent with those for women from the general population.

Interaction of reproductive tract infections with estrogen exposure on breast cancer risk and prognosis

BackgroundReproductive tract infections influenced a series of inflammatory processes which involved in the development of breast cancer, while the processes were largely affected by estrogen. The present study aimed to explore the associations of breast cancer risk and prognosis with reproductive tract infections and the modification effects of estrogen exposure.MethodsWe collected history of reproductive tract infections, menstruation and reproduction from 1003 cases and 1107 controls and a cohort of 4264 breast cancer patients during 2008–2018 in Guangzhou, China. We used logistic regression model to estimate the odds ratios (ORs) and 95% confidence intervals (CIs) for risk; Cox model was applied to estimate the hazard ratios (HRs) and 95% CIs for progression-free survival (PFS) and overall survival (OS).ResultsIt was found that previous reproductive tract infections were negatively associated with breast cancer risk (OR = 0.80, 95%CI, 0.65–0.98), particularly for patients with more menstrual cycles (OR = 0.74, 95%CI, 0.57–0.96). Patients with previous reproductive tract infections experienced better OS (HR = 0.61; 95% CI, 0.40–0.94) and PFS (HR = 0.84; 95% CI, 0.65–1.09). This protective effect on PFS was only found in patients with more menstrual cycles (HR = 0.52, 95% CI:0.34–0.79, Pinteraction = 0.015).ConclusionsThe findings suggested that reproductive tract infections may be protective for the initiation and development of breast cancer, particularly for women with a longer interval of lifetime estrogen exposure.

Abstract 5241: Association of polygenic risk scores with breast cancer risk among women with benign breast disease

Abstract Over one million biopsies are performed annually in the U.S. to evaluate suspicious breast lesions. Most biopsies lead to a diagnosis of benign breast disease (BBD) and these women have a 1.5- to fourfold increase in subsequent breast cancer (BC) risk compared with the general population. A polygenic risk score (PRS) including 313 common variants was developed to predict BC risk in the general population and has improved performance when added to existing BC prediction models. However, the value of PRS in risk prediction models among women with BBD has not been evaluated. To evaluate the role of the established PRS, BBD, and BC risk, we pooled data from 15,194 white women (6,706 BC cases and 8,488 controls) participating in five Breast Cancer Association Consortium case-control studies. BC risk associations were evaluated by self-reported BBD history and combinations of PRS expressed in tertiles using odds ratios (OR), considering the lowest category of PRS among women without BBD as the referent. Associations were also assessed in an independent case-cohort study (831 BC cases and 1,845 controls) using hazard ratios (HR). Among the case-control studies, the PRS was strongly associated with BC risk (OR=2.50 per standard deviation increase), and associations were similar in women with (OR=2.60) and without a history of BBD (OR=2.44, p-interaction=0.23). Women with BBD have a higher risk of BC than those without BBD within each level of PRS. Compared to women without BBD and in the lowest PRS category, those with BBD and PRS in the highest tertile had 5-fold increased odds of BC (OR = 5.38; 95% CI 4.73-6.13). Associations were similar in an independent case-cohort study. These findings indicate that BBD history and PRS are independent contributors to BC risk, and consideration of both simultaneously could improve breast cancer risk prediction. Future studies are needed to integrate PRS with other risk measures to refine absolute BC risk prediction among BBD patients. Associations of BC risk with combinations of PRS (tertiles) and history of BBD in five case-control studies and a case-cohort study from the Breast Cancer Association Consortium. Case-control studies Case-cohort study PRS score range History of BBD n BC cases n controls OR (95% CI)1 n BC cases n controls HR (95% CI)2 Tertile 1 (≤ -0.57) No 1009 2692 1.00 (Ref) 117 584 1.00 (Ref) Yes 508 902 1.54 (1.35-1.76) 69 163 2.05 (1.45-2.89) Tertile 2 (-0.58, -0.03) No 1469 2001 1.97 (1.78-2.17) 181 475 1.93 (1.48-2.51) Yes 760 798 2.65 (2.34-3.01) 108 170 2.99 (2.18-4.09) Tertile 3 (≥ -0.02) No 1910 1551 3.32 (3.01-3.67) 214 336 3.28 (2.52-4.26) Yes 1050 544 5.38 (4.73-6.13) 142 117 4.83 4.25-8.02) 1.Logistic regression analysis, adjusted for study site/genomic platform and age at enrollment. OR, odds ratio; CI, confidence interval.2.Cox proportional hazards regression analysis, accounting for the case-cohort study design and adjusted for age at enrollment. HR, hazard ratio; CI, confidence interval. Citation Format: Stacey J. Winham, Mark Sherman, Robert Vierkant, Bryan McCauley, Christopher Scott, Mia Gaudet, Melissa Troester, Sandhya Pruthi, Derek Radisky, Amy Degnim, Kristan Aronson, Rachel Murphy, Pascal Guenel, Therese Truong, Jenny Chang-Claude, Heiko Becher, Montserrat Garcia-Closas, Stephen Chanock, Thomas Ahearn, Xiaohong Yang, Doug Easton, Manjeet Bolla, Celine Vachon, Breast Cancer Association Consortium. Association of polygenic risk scores with breast cancer risk among women with benign breast disease. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 5241.

Traffic-Related Air Pollution and Breast Cancer Risk: A Systematic Review and Meta-Analysis of Observational Studies.

Current evidence of an association of breast cancer (BC) risk with air pollution exposure, in particular from traffic exhaust, remains inconclusive, and the exposure assessment methodologies are heterogeneous. This study aimed to conduct a systematic review and meta-analysis on the association between traffic-related air pollution (TRAP) and BC incidence (PROSPERO CRD42021286774). We systematically reviewed observational studies assessing exposure to TRAP and BC risk published until June 2022, available on Medline/PubMed and Web of Science databases. Studies using models for assessing exposure to traffic-related air pollutants or using exposure proxies (including traffic density, distance to road, etc.) were eligible for inclusion. A random-effects meta-analysis of studies investigating the association between NO2/NOx exposure and BC risk was conducted. Overall, 21 studies meeting the inclusion criteria were included (seven case-control, one nested case-control, 13 cohort studies); 13 studies (five case-control, eight cohort) provided data for inclusion in the meta-analyses. Individual studies provided little evidence of an association between TRAP and BC risk; exposure assessment methods and time periods of traffic emissions were different. The meta-estimate on NO2 exposure indicated a positive association (pooled relative risk per 10 µg/m3 of NO2: 1.015; 95% confidence interval, CI: 1.003; 1.028). No association between NOx exposure and BC was found (three studies). Although there was limited evidence of an association for TRAP estimated with proxies, the meta-analysis showed a significant association between NO2 exposure, a common TRAP pollutant marker, and BC risk, yet with a small effect size. Our findings provide additional support for air pollution carcinogenicity.

Variable number tandem repeats (VNTRs) as modifiers of breast cancer risk in carriers of BRCA1 185delAG.

Despite substantial efforts in identifying both rare and common variants affecting disease risk, in the majority of diseases, a large proportion of unexplained genetic risk remains. We propose that variable number tandem repeats (VNTRs) may explain a proportion of the missing genetic risk. Herein, in a pilot study with a retrospective cohort design, we tested whether VNTRs are causal modifiers of breast cancer risk in 347 female carriers of the BRCA1 185delAG pathogenic variant, an important group given their high risk of developing breast cancer. We performed targeted-capture to sequence VNTRs, called genotypes with adVNTR, tested the association of VNTRs and breast cancer risk using Cox regression models, and estimated the effect size using a retrospective likelihood approach. Of 303 VNTRs that passed quality control checks, 4 VNTRs were significantly associated with risk to develop breast cancer at false discovery rate [FDR] < 0.05 and an additional 4 VNTRs had FDR < 0.25. After determining the specific risk alleles, there was a significantly earlier age at diagnosis of breast cancer in carriers of the risk alleles compared to those without the risk alleles for seven of eight VNTRs. One example is a VNTR in exon 2 of LINC01973 with a per-allele hazard ratio of 1.58 (1.07-2.33) and 5.28 (2.79-9.99) for the homozygous risk-allele genotype. Results from this first systematic study of VNTRs demonstrate that VNTRs may explain a proportion of the unexplained genetic risk for breast cancer.

Long-term exposure to nitrogen dioxide air pollution and breast cancer risk: A nested case-control within the French E3N cohort study

Nitrogen dioxide (NO2) is an important air pollutant due to its adverse effects on human health. Yet, current evidence on the association between NO2 and the risk of breast cancer lacks consistency. In this study, we investigated the association between long-term exposure to NO2 and breast cancer risk in the French E3N cohort study. Association of breast cancer risk with NO2 exposure was assessed in a nested case-control study within the French E3N cohort including 5222 breast cancer cases identified over the 1990–2011 follow-up period and 5222 matched controls. Annual mean concentrations of NO2 at participants’ residential addresses for each year from recruitment 1990 through 2011, were estimated using a land use regression (LUR) model. Multivariable conditional logistic regression models were used to compute odds ratios (ORs) and their 95% confidence intervals (CIs). Additional analyses were performed using NO2 concentrations estimated by CHIMERE, a chemistry transport model. Overall, the mean NO2 exposure was associated with an increased risk of breast cancer. In all women, for each interquartile range (IQR) increase in NO2 levels (LUR: 17.8 μg/m3), the OR of the model adjusted for confounders was 1.09 (95% CI: 1.01–1.18). The corresponding OR in the fully adjusted model (additionally adjusted for established breast cancer risk factors) was 1.07 (95% CI: 0.98–1.15). By menopausal status, results for postmenopausal women were comparable to those for all women, while no association was observed among premenopausal women. By hormone receptor status, the OR of estrogen receptor positive breast cancer = 1.07 (95% CI: 0.97–1.19) in the fully adjusted model. Additional analyses using the CHIMERE model showed slight differences in ORs estimates. The results of this study indicate an increased risk of breast cancer associated with long-term exposure to NO2 air pollution. Observing comparable effects of NO2 exposure estimated by two different models, reinforces these findings.

Rat Mammary carcinoma susceptibility 3 (Mcs3) pleiotropy, socioenvironmental interaction, and comparative genomics with orthologous human 15q25.1-25.2.

Genome-wide association studies of breast cancer susceptibility have revealed risk-associated genetic variants and nominated candidate genes; however, the identification of causal variants and genes is often undetermined by genome-wide association studies. Comparative genomics, utilizing Rattus norvegicus strains differing in susceptibility to mammary tumor development, is a complimentary approach to identify breast cancer susceptibility genes. Mammary carcinoma susceptibility 3 (Mcs3) is a Copenhagen (COP/NHsd) allele that confers resistance to mammary carcinomas when introgressed into a mammary carcinoma susceptible Wistar Furth (WF/NHsd) genome. Here, Mcs3 was positionally mapped to a 7.2-Mb region of RNO1 spanning rs8149408 to rs107402736 (chr1:143700228-150929594, build 6.0/rn6) using WF.COP congenic strains and 7,12-dimethylbenz(a)anthracene-induced mammary carcinogenesis. Male and female WF.COP-Mcs3 rats had significantly lower body mass compared to the Wistar Furth strain. The effect on female body mass was observed only when females were raised in the absence of males indicating a socioenvironmental interaction. Furthermore, female WF.COP-Mcs3 rats, raised in the absence of males, did not develop enhanced lobuloalveolar morphologies compared to those observed in the Wistar Furth strain. Human 15q25.1-25.2 was determined to be orthologous to rat Mcs3 (chr15:80005820-82285404 and chr15:83134545-84130720, build GRCh38/hg38). A public database search of 15q25.1-25.2 revealed genome-wide significant and nominally significant associations for body mass traits and breast cancer risk. These results support the existence of a breast cancer risk-associated allele at human 15q25.1-25.2 and warrant ultrafine mapping of rat Mcs3 and human 15q25.1-25.2 to discover novel causal genes and variants.

Occupational heat exposure and prostate cancer risk: a pooled analysis of case-control studies

Background and aim: Heat exposures occur frequently in many indoor and outdoor occupations. In our previous work, we observed some evidence for a positive association of occupational heat exposure and breast cancer risk. Here we seek to examine potential associations with prostate cancer risk in a large multi-country study. Methods: We performed a pooled analysis of data from 3,175 histologically confirmed prostate cancer cases and 3,529 frequency-matched controls from studies in three different countries, Spain, France, and Canada. The Finnish job exposure matrix, FINJEM, was used to apply estimates of occupational heat exposure to the lifetime occupational history of participants. Three main exposure indices were used: ever vs. never exposed, lifetime cumulative exposure (heat stress years) and duration of exposure (years) with a lag period of 5 years. We estimated odds ratios (ORs) and 95% confidence intervals (CIs), using conditional logistic regression models stratified by 5-year age groups and study and adjusted for potential confounders. Results: A total of 32% of cases and 33% of controls were classified as being ever occupationally exposed to heat. Highest heat exposed occupations included ore and metal furnace operators, firefighters, and bakers. We found no evidence for an association of ever occupational heat exposure and prostate cancer risk (OR 0.92; 95% CI 0.83, 1.03). There were also no associations observed in the highest categories of lifetime cumulative exposure or duration, and there was no evidence for a trend. Results did not change when stratifying by Gleason scores. When analysing the Spanish case-control study separately using a Spanish job exposure matrix developed for local working conditions, some odds ratios were elevated, though results were imprecise. Conclusions: Findings from this pooled study have provided no strong evidence for an association between occupational heat exposure and prostate cancer risk. Keywords: prostate cancer, occupational exposures, heat, pooled analysis

Association between the rs4784227-CASC16 polymorphism and the risk of breast cancer: A meta-analysis.

Objective:Although several studies have identified an association between the rs4784227-cancer susceptibility candidate gene 16 (CASC16) polymorphism and breast cancer, the results remain inconclusive. Therefore, we conducted a meta-analysis to assess the relationship between the rs4784227-CASC16 polymorphism and breast cancer risk.Methods:Studies were searched in the PubMed, Web of Science, Embase, Google Scholar, and Cochran Library databases until June 10, 2021, to identify all potential literature on rs4784227-CASC16 polymorphism and breast cancer risk association. Fixed-effect or random-effect models were used to calculate odds ratios (ORs) and their corresponding 95% confidence intervals (95% CIs). Subgroup analyses, publication bias, and sensitivity analyses were also conducted.Results:Seventeen eligible studies involving 34,719 subjects (18,445 cases and 16,274 healthy controls) from 7 articles were included in the current meta-analysis. The pooled ORs regarding the association between the rs4784227-CASC16 polymorphism and breast cancer risk were statistically significant [T vs C: OR = 1.244, 95% CI = 1.202–1.287; TT vs CT + CC: OR = 1.407, 95% CI = 1.296–1.528; CC vs CT + TT: OR = 0.777, 95% CI = 0.745–0.811; TT vs CC: OR = 1.544, 95% CI = 1.419–1.681; CT vs CC: OR = 1.244, 95% CI = 1.189–1.301]. On subgroup analysis, the rs4784227-CASC16 T/C gene has a certain correlation with breast cancer susceptibility in Asian and North American populations, but no significant risk in the Australian population.Conclusion:Our pooled analysis showed a significant association between the rs4784227- (T) allele and breast cancer susceptibility in Asian and North American populations, and intervention with this mutation might be a new therapeutic strategy for breast cancer. However, large-scale and well-designed studies are needed in different populations to further evaluate the role of the rs4784227-CASC16 polymorphism in breast cancer.

A metabolomic analysis of adiposity measures and pre- and postmenopausal breast cancer risk in the Nurses' Health Studies.

Adiposity is consistently positively associated with postmenopausal breast cancer and inversely associated with premenopausal breast cancer risk, though the reasons for this difference remain unclear. In this nested case-control study of 1649 breast cancer cases and 1649 matched controls from the Nurses' Health Study (NHS) and the NHSII, we selected lipid and polar metabolites correlated with BMI, waist circumference, weight change since age 18, or derived fat mass, and developed a metabolomic score for each measure using LASSO regression. Logistic regression was used to investigate the association between this score and breast cancer risk, adjusted for risk factors and stratified by menopausal status at blood draw and diagnosis. Metabolite scores developed among only premenopausal or postmenopausal women were highly correlated with scores developed in all women (r = 0.93-0.96). Higher metabolomic adiposity scores were generally inversely related to breast cancer risk among premenopausal women. Among postmenopausal women, significant positive trends with risk were observed (e.g., metabolomic waist circumference score OR Q4 vs. Q1 = 1.47, 95% CI = 1.03-2.08, P-trend = 0.01). Though the same metabolites represented adiposity in pre- and postmenopausal women, breast cancer risk associations differed suggesting that metabolic dysregulation may have a differential association with pre- vs. postmenopausal breast cancer.

Abstract 2249: A metabolomic analysis of adiposity measures and pre- and postmenopausal breast cancer risk in the Nurses’ Health Studies

Abstract Adiposity is consistently positively associated with postmenopausal breast cancer and inversely associated with premenopausal breast cancer risk. In this nested case-control study of 1651 breast cancer cases and 1651 matched controls from the Nurses’ Health Study (NHS) and the Nurses’ Health Study II (NHSII), we selected lipids and polar metabolites correlated with BMI, waist circumference, weight change since age 18, or derived fat mass, developed a metabolomic score for each measure using LASSO regression, and used logistic regression to investigate the association between this score and breast cancer risk adjusted for risk factors. Analyses were stratified by menopausal status at blood draw and diagnosis. We further explored risk of ER+ and ER- breast cancer.Metabolite correlations were similar across adiposity measures. Metabolite scores developed among only premenopausal or postmenopausal women were highly correlated with scores developed in all women (r=0.94-0.96). Higher metabolomic adiposity scores were generally inversely related to breast cancer risk among premenopausal women. Among postmenopausal women, significant positive trends with risk were observed for higher metabolomic adiposity scores (e.g., metabolomic waist circumference score OR Q4 v. Q1=1.55, 95% CI=1.08-2.22, p-trend=0.01). Metabolites associated with adiposity and breast cancer risk, glycerophosphocholines and branched-chain amino acids, are also associated with metabolic dysregulation. The same metabolites represented adiposity in pre- and postmenopausal women, though breast cancer risk associations still differed by menopausal status. Thus, metabolic dysregulation may have a differential association with pre- vs. postmenopausal breast cancer. Investigation of these metabolites and their role in adiposity-related breast cancer risk should be further explored. Citation Format: Kristen D. Brantley, Oana A. Zeleznik, Barbra A. Dickerman, Raji Balasubramanian, Clary B. Clish, Julian Avila-Pacheco, Bernard Rosner, Rulla M. Tamimi, A. Heather Eliassen. A metabolomic analysis of adiposity measures and pre- and postmenopausal breast cancer risk in the Nurses’ Health Studies [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2249.