Lifestyle Risk Factors For Breast Cancer Research Articles

Abstract C66: Adverse childhood experiences and breast cancer risk factors in black and white women

Abstract Introduction: Adverse childhood experiences (ACE) have been implicated in several adult chronic diseases. ACE may also be associated with reproductive and lifestyle factors and biomarkers associated with breast cancer overall, and with estrogen receptor negative (ER-) disease specifically. Methods: We examined whether self-reported ACE (verbal, physical, or sexual abuse; household mental illness or substance abuse; domestic violence, parental separation/divorce, and incarcerated household members) was associated with several reproductive and lifestyle breast cancer risk factors including age at menarche and age at first birth, and four biomarkers: adiponectin, C-peptide, high sensitivity C-reactive protein (hsCRP), and insulin-like growth factor-1 (IGF-1). The study population included 16,062 black and white women in the Southern Community Cohort Study. We grouped women into three categories: 0 experiences, 1-2 experiences and 3-10 experiences (high). Cross-sectional associations were analysed using logistic or linear regression. Results: Women with high ACE were more likely to have: menarche before age 12, ever breastfed, more than two births, first birth before age 18, initiated smoking before age 16, and be current smokers compared to those with no ACE. Parous women with high ACE were 54% more likely to have ever breastfed (OR: 1.54, 95% CI: 1.39, 1.70; p-trend <0.0001) and 65% more likely to have first given birth before age 18 (OR: 1.65, 95% CI: 1.48, 1.85; p-trend <0.0001). ACE was not associated with body mass index (BMI) at enrollment, BMI at age 21, adiponectin, C-peptide or hsCRP levels. ACE was inversely associated with IGF-1. Women with high ACE had mean IGF-1 levels of 104.3 ng/ml compared to 119.2 ng/ml among women with no ACE (p-trend=0.007). Results generally did not differ between Blacks and Whites. Conclusions: Our findings suggest that ACE is associated with reproductive patterns that have been shown to increase risk of ER- breast cancer. Future work should examine associations between ACE and breast cancer risk according to ER status. Citation Format: Erica T. Warner, Margaret K. Hargreaves, Charles P. Mouton, Rulla M. Tamimi, Lisa B. Signorello. Adverse childhood experiences and breast cancer risk factors in black and white women. [abstract]. In: Proceedings of the Eighth AACR Conference on The Science of Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; Nov 13-16, 2015; Atlanta, GA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2016;25(3 Suppl):Abstract nr C66.

Association of H3K9me3 and H3K27me3 repressive histone marks with breast cancer subtypes in the Nurses' Health Study.

Repressive histone tail modifications have been associated with molecular breast cancer subtypes. We investigated whether histone 3 lysine 9 trimethylation (H3K9me3) and histone 3 lysine 27 trimethylation (H3K27me3) were associated with tumor features and subtypes while adjusting for prospectively collected reproductive and lifestyle breast cancer risk factors. We have tissue microarray data with immunohistochemical marker information on 804 incident cases of invasive breast cancer diagnosed from 1976-2000 in the Nurses' Health Study. Tissue microarray sections were stained for global H3K9me3 and H3K27me3, and scored into four categories. Multivariate odds ratios (OR) and 95 % confidence intervals (CI) were calculated using logistic regression models for tumor features and subtypes, adjusting for breast cancer risk factors. While there were no significant associations between H3K9me3 and tumor features, H3K27me3 was significantly associated with lower grade tumors compared to high grade tumors in the multivariate model (OR = 1.95, 95 % CI 1.35-2.81, p = 0.0004). H3K27me3 was suggestively associated with estrogen receptor-positive (ER+) tumors (OR = 1.47, 95 % CI 0.97-2.23, p = 0.07). In subtype analyses, H3K27me3 was positively associated with the luminal A subtype compared to all other subtypes (OR = 1.42, 95 % CI 1.14-1.77, p = 0.002), and was inversely associated with HER2-type (OR = 0.58, 95 % CI 0.37-0.91, p = 0.02) and basal-like breast cancer (OR = 0.52, 95 % CI 0.36-0.76, p = 0.0006). In the largest immunohistochemical examination of H3K9me3 and H3K27me3 in breast cancer, we found that H3K27me3 positivity, but not H3K9me3, was associated with lower grade tumors and the luminal A subtype after adjusting for reproductive and lifestyle breast cancer risk factors.