Association between diet during preadolescence and adolescence and risk for breast cancer during adulthood

Impact of a Cancer Health Education Curriculum Among Milwaukee Public High School Students

In Milwaukee and nationwide, cancer incidence, late-stage diagnosis, and mortality are notably higher among some racial/ethnic populations. Cancer education has the potential to impact cancer burden and reduce cancer disparities. In particular, the addition of a service-learning component to academic curriculums has been shown to improve student learning as well as positively impact the surrounding community. This study implemented a cancer health education curriculum (CHEC) at a Milwaukee public high school with the goal of addressing cancer knowledge, fear and fatalism beliefs, and risk behaviors. The curriculum included interactive learning sessions and a service-learning final project. Five-hundred twenty-one students also completed pre- and post-surveys assessing cancer knowledge, fear and fatalism, risk behaviors, cancer-related communication, and a qualitative question asking what they hoped to gain (pre) or did gain (post) from the course. Results indicate (1) a significant improvement in cancer knowledge (p < 0.0001), (2) a decrease in cancer fear and fatalism (p < 0.0001), (3) an increase in fruit consumption (p < 0.0001), (4) a decrease in screen time (p = 0.0004), and (5) an increase in how often students spoke with their family about cancer (p < 0.0001). Qualitative data reflect important gains such as increased interest in sharing their knowledge about cancer with their community. Providing cancer education and leveraging a service-learning requirement led to notable changes in high school students' cancer knowledge, fear and fatalism, and risk behaviors. Students also communicated more with family/friends about cancer. Such efforts could have broader implications for student, family, and community cancer burden.

Investigating the Link between Early Life and Breast Anomalies

Several factors during childhood and adolescence are thought to be associated with the development of proliferative benign breast diseases and breast cancer in adulthood. In order to identify them, the authors conducted an extensive review of the literature up to October 2022, searching for clinical studies, reports, and guidelines in English. A thorough Medline/Pubmed and Google scholar database research was performed, investigating the link between diet, exercise, age of menarche, body mass index, ionizing radiation exposure during childhood and adolescence, and proliferative breast diseases and breast cancer in adulthood. A list of keywords, including breast disorders, adolescence, childhood, and breast cancer was included in our search algorithm. Numerous studies concede that the development of breast disease in adulthood is influenced by various risk factors, whose influence begins during early childhood and adolescence.

How Does Consistency of Food and Nutrition Support Effect Daily Food Consumption among Children Living in Poverty? Recession-Era Implications

Underutilization of the Special Supplemental Nutrition Program for Women, Infants and Children (WIC) and the Supplemental Nutrition Assistance (SNAP) food safety net programs may compromise child nutritional benefits for families with limited incomes. Using a sample of children surveyed before (2003−2006) and after the Great Recession (2007−2009), we examine whether consistent access to WIC and SNAP during times of increased economic stress moderated the association between poverty level (i.e., income-needs ratio [INR]) and fruits and vegetables (FV) or foods high in saturated fats and added sugars (SFAS). Fragile Families and Child Wellbeing Study income-eligible mothers/children (≤185% of poverty) with available FV and SFAS data at the 5- (2003−2006) and 9-year (2007−2010) waves (n = 733) were included. Main effects of INR and interaction effects of consistency of WIC, SNAP, and dual WIC and SNAP support from birth through age 5 were examined. INR was associated with decreased FV consumption frequency from age 5 to 9, conditional upon consistency of dual WIC/SNAP enrollment. FV declined when there was low consistency (<1 year) of dual support. FV consumption was stable across INR when combined WIC/SNAP support lasted at least 2 years. Results can inform strategies for optimizing the nutritional impact of WIC and SNAP by focusing on those most at risk for underutilization of multiple benefits.

The relationship between health literacy and correlates of adolescents' obesogenic and substance use behaviors

PURPOSE

Risk perception (RP) and self-efficacy are targeted in adolescent health behavior interventions, however these variables have not been explored in relation to health literacy (HL). HL may affect how adolescents assess, prioritize, and integrate information when forming RP and self-efficacy and, ultimately, their health behaviors. This study assessed the relationship between functional, interactive, and critical HL and adolescents' behavior-specific RP and self-efficacy and health behaviors.

DESIGN AND METHODS

Cross-sectional data were collected from 380 adolescents attending high school via an online survey. Survey measures included demographics, functional, interactive, and critical HL, and substance use and obesogenic behavior-related beliefs, attitudes, and behaviors. Pearson correlations and regressions were estimated.

RESULTS

The relationship between HL and RP, self-efficacy, and behaviors varied by behavior and HL type. Critical HL was related to obesogenic-specific RP and behaviors, while interactive and critical HL were related to self-efficacy. Interactive and critical HL were related to substance use-specific RP and self-efficacy while functional and interactive HL were related to substance use behaviors. HL moderated several RP/behavior and self-efficacy/behavior relationships.

CONCLUSIONS

The significant relationships between HL and RP and self-efficacy highlight how HL may be an underlying factor or help shape adolescents' perceptions and beliefs adolescents have about behaviors and themselves, which ultimately influence their behaviors.

PRACTICAL IMPLICATIONS

Adolescent interventions should be assessed to determine what underlying HL skills are needed for behavior change and assess and address HL directly as adolescents with low HL may be at a disadvantage for intervention uptake and outcomes.

Association Between Birthplace and Time in the United States With Diet Quality in US Adolescents: Findings from the National Health and Nutrition Examination Survey, 2007 to 2018

BACKGROUND

During adolescence, diet quality reaches its lowest point compared to other childhood life stages. Acculturation is associated with decreased diet quality among many groups of US immigrant adults, but research is limited among adolescents.

OBJECTIVES

We investigated the associations between birthplace and length of time living in the United States, 2 proxy measures of acculturation, and diet quality among adolescents (12-19 years old).

METHODS

Data were from the NHANES (2007-2018), which included two 24-hour dietary recalls (n = 6113) to estimate Healthy Eating Index 2015 (HEI-2015) total scores and component scores. Multivariate linear regression and generalized linear models were performed to compare HEI-2015 total scores and component scores between US-born adolescents (n = 5342) and foreign-born adolescents with <5 years (n = 244), 5 to <10 years (n = 201), and ≥10 years (n = 290) of US residency.

RESULTS

Foreign-born adolescents with <5 years (53.3 ± 1.2), 5 to <10 years (51.4 ± 1.5), and ≥10 years of US residency (49.9 ± 0.8) had higher HEI-2015 total scores than US-born adolescents (47.0 ± 0.3; P < 0.0001) and higher component scores for total vegetables, seafood and plant proteins, and added sugars (P values ≤ 0.0001). Foreign-born adolescents with more years of US residency had higher component scores for total fruits, whole fruits, and saturated fats than those with fewer years of US residency. A sensitivity analysis revealed this pattern held for Mexican-American and other Hispanic adolescents.

CONCLUSIONS

Being born outside the United States and living in the United States for less time (among foreign-born adolescents) are associated with higher diet quality. Culturally informed health promotion programs may help to reduce diet-related disparities related to acculturation among adolescents.

Habitual Phytoestrogen Intake Is Associated with Breast Composition in Girls at 2 Years after Menarche Onset

BACKGROUND

High phytoestrogen intake during adolescence is associated with a reduced risk of breast cancer. Breast density (BD) is a strong predictor of breast cancer and can be considered an early marker. We aim to assess the association between the mean habitual intake of isoflavones, lignans, and total phytoestrogens intake during puberty until 2 years after menarche onset and absolute fibroglandular volume (AFGV) and percentage of fibroglandular volume (%FGV) in Hispanic girls at the end of puberty.

METHODS

Longitudinal study set up in the Growth and Obesity Chilean Cohort Study (GOCS). We included 329 girls with dietary data (multiple 24-hours recalls) from puberty until 2 years after menarche onset (81% had 2-4 recalls). Two international datasets were used to estimate isoflavones, lignans, and total phytoestrogens in the diet. Breast composition was measured by dual energy X-ray absorptiometry at 2 years after menarche. Multiple linear regression models were used to assess the association between isoflavones, lignans, and total phytoestrogens intake and AFGV and %FGV.

RESULTS

The average total phytoestrogen intake was 1 mg/day and %FGV was 50.7% (SD = 15.2) and AFGV 218.8 cm3 (SD = 79.3). An inverse association was found between consumption of isoflavones and AFGV, as well as, with total phytoestrogens [Q4 vs. Q1 adjusted model ß = -49.2 cm3; 95% CI (-85.5 to -13.0)].

CONCLUSIONS

Girls with a higher intake of total phytoestrogens and isoflavones during puberty until 2 years after menarche onset had significantly lower AFGV.

IMPACT

Although the intake of phytoestrogens is low in Western populations, higher consumption of them during a critical period of life like puberty could be beneficial to reduce breast cancer during adulthood.

Place Is Power: Investing in Communities as a Systemic Leverage Point to Reduce Breast Cancer Disparities by Race

Racial disparities in breast cancer present a vexing and complex challenge for public health. A diverse array of factors contributes to disparities in breast cancer incidence and outcomes, and, thus far, efforts to improve racial equity have yielded mixed results. Systems theory offers a model that is well-suited to addressing complex issues. In particular, the concept of a systemic leverage point offers a clue that may assist researchers, policymakers, and interventionists in formulating innovative and comprehensive approaches to eliminating racial disparities in breast cancer. Naming systemic racism as a fundamental cause of disparities, we use systems theory to identify residential segregation as a key leverage point and a driver of racial inequities across the social, economic, and environmental determinants of health. We call on researchers, policymakers, and interventionists to use a systems-informed, community-based participatory approach, aimed at harnessing the power of place, to engage directly with community stakeholders in coordinating efforts to prevent breast cancer, and work toward eliminating disparities in communities of color.

Cabbage and Sauerkraut Consumption in Adolescence and Adulthood and Breast Cancer Risk among US-Resident Polish Migrant Women

Background: Breast cancer (BC) incidence and mortality are lower in Poland than in the United States (US). However, Polish-born migrant women to US approach the higher BC mortality rates of US women. We evaluated the association between consumption of cabbage/sauerkraut foods and BC risk in Polish-born migrants to US. Methods: We conducted a case–control study of BC among Polish-born migrants in Cook County and the Detroit Metropolitan Area. Cases (n = 131) were 20–79 years old with histological/cytological confirmation of invasive BC. Population-based controls (n = 284) were frequency matched to cases on age and residence. Food frequency questionnaires assessed diet during adulthood and age 12–13 years. Odds ratios (OR) and 95% confidence intervals (95% CI) were estimated with conditional logistic regression. Consumption of total, raw/short-cooked, and long-cooked cabbage/sauerkraut foods was categorized as low, medium, or high (frequency of servings/week). Results: Higher consumption of total and raw/short-cooked cabbage/sauerkraut foods, during both adolescence and adulthood, was associated with a significantly lower BC risk. Consumption of long-cooked cabbage/sauerkraut foods was low and not significantly associated with risk. The multivariate OR for total cabbage/sauerkraut consumption, high vs. low (>4 vs. ≤2 servings/week) during adolescence was 0.36 (95% CI = 0.18–0.71, p_trend < 0.01) and 0.50 (95% CI = 0.23–1.06, p_trend = 0.08) during adulthood. For raw/short-cooked cabbage/sauerkraut (>3 vs. ≤1.5 servings/week), the ORs were 0.35 (95% CI = 0.16–0.72, p_trend < 0.01) during adolescence and 0.37 (95% CI = 0.17–0.78, p_trend < 0.01) during adulthood. For joint adolescent/adult consumption of raw/short-cooked cabbage/sauerkraut foods, (high, high) vs. (low, low), the OR was 0.23 (95% CI = 0.07–0.65). The significant association for high adolescent consumption of raw/short-cooked cabbage/sauerkraut foods and reduced BC risk was consistent across all levels of consumption in adulthood. Conclusion: Greater consumption of total and raw/short-cooked cabbage/sauerkraut foods either during adolescence or adulthood was associated with significantly reduced BC risk among Polish migrant women. These findings contribute to the growing literature suggesting a protective effect of a potentially modifiable factor, cruciferous vegetable intake, on breast cancer risk.

Food and drink marketing on social media and dietary intake in Australian adolescents: Findings from a cross-sectional survey

Unhealthy food and drink marketing is prominent on social media and use of such platforms is widespread among adolescents. This study aims to examine the association between exposure to and engagement with food or drink advertisements on social media and unhealthy food and drink intake in Australian adolescents. In 2018, a representative sample of secondary school students aged 12-17 years (N = 8708) self-reported how frequently they saw food or drink advertisements on social media (exposure), 'liked' or 'shared' food or drink posts (engagement), and consumption of various unhealthy food and drinks. Multilevel logistic regression assessed the association between exposure to and engagement with food marketing on social media and high intake of unhealthy food and drinks. Fifty-five percent of students reported seeing a food or drink advertisement on social media at least weekly, while engagement was less frequent. Exposure to a food or drink advertisement on social media at least once in the last week was associated with a high intake of unhealthy drinks, while liking or sharing a food or drink post at least once in the last month was associated with a high intake of unhealthy food and drinks (all p < 0.01). As frequency of engagement with this type of marketing increased, so too did the likelihood of a high intake of unhealthy food and drinks. The association between exposure to and engagement with food or drink marketing and high unhealthy drink intake was driven by males, while all associations persisted irrespective of age. Holding manufacturers to higher standards in their digital marketing of unhealthy food and drink products through improved policy design and enforcement capability may be crucial in enabling young individuals to maintain a healthy diet.

Adolescent dairy product and calcium intake in relation to later prostate cancer risk and mortality in the NIH-AARP Diet and Health Study

PURPOSE

Although a growing body of evidence supports an early-life contribution to prostate cancer (PCa) development, few studies have investigated early-life diet, and only three have examined early-life dairy product intake, a promising candidate risk factor because of its known/suspected influence on insulin-like growth factor levels and height.

METHODS

We used recalled dietary data from 162,816 participants in the NIH-AARP Diet and Health Study to investigate associations for milk, cheese, ice cream, total dairy, and calcium intake at ages 12-13 years with incident total (n = 17,729), advanced (n = 2,348), and fatal PCa (n = 827) over 14 years of follow-up. We calculated relative risks (RRs) and 95% confidence intervals (CIs) by Cox proportional hazards regression.

RESULTS

We observed suggestive positive trends for milk, dairy, and calcium intake with total and/or advanced PCa (p-trends = 0.016-0.148). These trends attenuated after adjustment for additional components of adolescent diet, particularly red meat and vegetables/potatoes. In contrast, suggestive inverse trends were observed for cheese and ice cream intake with total and/or advanced PCa (p-trends = 0.043-0.153), and for milk, dairy, and calcium intake with fatal PCa (p-trend = 0.045-0.117).

CONCLUSION

Although these findings provide some support for a role of adolescent diet in increasing PCa risk, particularly for correlates of milk intake or overall dietary patterns, our protective findings for cheese and ice cream intake with PCa risk and mortality, and for all dairy products with PCa mortality, suggest alternative explanations, such as the influence of early-life socioeconomic status, and increased PCa screening, earlier detection, and better PCa care.

Adolescent caffeine consumption and mammographic breast density in premenopausal women

PURPOSE

Previous studies suggest that coffee and caffeine intake may be associated with reduced breast cancer risk. To date, there is limited and inconsistent epidemiologic evidence for associations of adolescent diet with mammographic breast density, a strong and consistent predictor of breast cancer. We investigated the association of adolescent caffeine intake with mammographic density in premenopausal women.

METHODS

This study included 751 cancer-free women within the Nurses' Health Study II cohort. Percent breast density (PD), absolute dense (DA) and non-dense areas (NDA) were measured from digitized film mammograms using a computer-assisted thresholding technique; all measures were square root-transformed. Energy-adjusted adolescent caffeine intake was estimated using the data from a food frequency questionnaire. Information regarding breast cancer risk factors was obtained from questionnaires closest to the mammogram date. We used generalized linear regression to quantify associations of caffeine intake with breast density measures.

RESULTS

In multivariable analyses, adolescent caffeine intake was not associated with any of the density phenotypes (caffeine 4th vs. 1st quartile: β = - 1.27, 95% CI - 4.62; 2.09, p-trend = 0.55 for percent density; β = - 0.21, 95% CI - 0.76, 0.34, p-trend = 0.65 for absolute dense area, and β = 0.23, 95% CI - 0.28, 0.74, p-trend = 0.50 for non-dense area). Additional adjustment of the models for body mass index at age 18 resulted in attenuation of the risk estimates.

CONCLUSIONS

Our findings do not support the hypothesis that adolescent caffeine intake is associated with premenopausal mammographic breast density.

Early Life Exposures and Adult Cancer Risk

Very little is known about the influence of early life exposures on adult cancer risk. The purpose of this narrative review was to summarize the epidemiologic evidence relating early life tobacco use, obesity, diet, and physical activity to adult cancer risk; describe relevant theoretical frameworks and methodological strategies for studying early life exposures; and discuss policies and research initiatives focused on early life. Our findings suggest that in utero exposures may indirectly influence cancer risk by modifying biological pathways associated with carcinogenesis; however, more research is needed to firmly establish these associations. Initiation of exposures during childhood and adolescence may impact cancer risk by increasing duration and lifetime exposure to carcinogens and/or by acting during critical developmental periods. To expand the evidence base, we encourage the use of life course frameworks, causal inference methods such as Mendelian randomization, and statistical approaches such as group-based trajectory modeling in future studies. Further, we emphasize the need for objective exposure biomarkers and valid surrogate endpoints to reduce misclassification. With the exception of tobacco use, there is insufficient evidence to support the development of new cancer prevention policies; however, we highlight existing policies that may reduce the burden of these modifiable risk factors in early life.

Racial/Ethnic Differences in the Impact of Neighborhood Social and Built Environment on Breast Cancer Risk: The Neighborhoods and Breast Cancer Study

Background: Neighborhood socioeconomic status (nSES) has been found to be associated with breast cancer risk. It remains unclear whether this association applies across racial/ethnic groups independent of individual-level factors and is attributable to other neighborhood characteristics.Methods: We examined the independent and joint associations of education and nSES with odds of breast cancer. Residential addresses were geocoded for 2,838 cases and 3,117 controls and linked to nSES and social and built environment characteristics. We estimated ORs and 95% confidence intervals (CI) using multilevel logistic regression controlling for individual-level breast cancer risk factors and assessed the extent to which nSES associations were due to neighborhood characteristics.Results: Women living in the highest versus lowest nSES quintile had a nearly 2-fold greater odds of breast cancer, with elevated odds (adjusted ORs, 95% CI) for non-Hispanic whites (NHWs; 2.27; 1.45-3.56), African Americans (1.74; 1.07-2.83), U.S.-born Hispanics (1.82; 1.19-2.79), and foreign-born Hispanics (1.83; 1.06-3.17). Considering education and nSES jointly, ORs were increased for low education/high nSES NHWs (1.83; 1.14-2.95), high education/high nSES NHWs (1.64; 1.06-2.54), and high education/high nSES foreign-born Hispanics (2.17; 1.52-3.09) relative to their race/ethnicity/nativity-specific low education/low nSES counterparts. Adjustment for urban and mixed-land use characteristics attenuated the nSES associations for most racial/ethnic/nativity groups except NHWs.Conclusions: Our study provides empirical evidence for a role of neighborhood environments in breast cancer risk, specifically social and built environment attributes.Impact: Considering the role of neighborhood characteristics among diverse populations may offer insights to understand racial/ethnic disparities in breast cancer risk. Cancer Epidemiol Biomarkers Prev; 26(4); 541-52. ©2017 AACR.

A Systematic Literature Review and Meta-Regression Analysis on Early-Life Energy Restriction and Cancer Risk in Humans

Background

In animal models, long-term moderate energy restriction (ER) is reported to decelerate carcinogenesis, whereas the effect of severe ER is inconsistent. The impact of early-life ER on cancer risk has never been reviewed systematically and quantitatively based on observational studies in humans.

Objective

We conducted a systematic review of observational studies and a meta-(regression) analysis on cohort studies to clarify the association between early-life ER and organ site-specific cancer risk.

Methods

PubMed and EMBASE (1982 –August 2015) were searched for observational studies. Summary relative risks (RRs) were estimated using a random effects model when available ≥3 studies.

Results

Twenty-four studies were included. Eleven publications, emanating from seven prospective cohort studies and some reporting on multiple cancer endpoints, met the inclusion criteria for quantitative analysis. Women exposed to early-life ER (ranging from 220–1660 kcal/day) had a higher breast cancer risk than those not exposed (RR_{RE all ages} = 1.28, 95% CI: 1.05–1.56; RR_{RE for 10–20 years of age} = 1.21, 95% CI: 1.09–1.34). Men exposed to early-life ER (ranging from 220–800kcal/day) had a higher prostate cancer risk than those not exposed (RR_RE = 1.16, 95% CI: 1.03–1.30). Summary relative risks were not computed for colorectal cancer, because of heterogeneity, and for stomach-, pancreas-, ovarian-, and respiratory cancer because there were <3 available studies. Longer duration of exposure to ER, after adjustment for severity, was positively associated with overall cancer risk in women (p = 0.02). Ecological studies suggest that less severe ER is generally associated with a reduced risk of cancer.

Conclusions

Early-life transient severe ER seems to be associated with increased cancer risk in the breast (particularly ER exposure at adolescent age) and prostate. The duration, rather than severity of exposure to ER, seems to positively influence relative risk estimates. This result should be interpreted with caution due to the limited number of studies and difficulty in disentangling duration, severity, and geographical setting of exposure.

Psychosocial Adjustment and Perceived Risk Among Adolescent Girls From Families With BRCA1/2 or Breast Cancer History

PURPOSE

To evaluate the impact of breast cancer family history and maternal BRCA1/2 mutation on the psychosocial adjustment and perceived risk in girls age 11 to 19 years old.

MATERIALS AND METHODS

Girls age 11 to 19 years old with one or more relatives with breast cancer or a familial BRCA1/2 mutation (breast cancer family history [BCFH] positive, n = 208; n = 69 with BRCA1/2-positive mother), peers (BCFH negative, n = 112), and their mothers completed assessments of psychosocial adjustment, breast cancer-specific distress, and perceived risk of breast cancer.

RESULTS

General psychosocial adjustment did not differ significantly between BCFH-positive and BCFH-negative girls, either by self-report or mother report, except for higher self-esteem among BCFH-positive girls (P = .01). BCFH-positive girls had higher breast cancer-specific distress than BCFH-negative girls (P < .001), but girls from BRCA1/2-positive families did not differ from other BCFH-positive peers. BCFH-positive girls were more likely to report themselves at increased self-risk for breast cancer in adulthood than BCFH-negative peers (74% v 33%, respectively; P ≤ .001). Girls from BRCA1/2-positive families were more likely than other BCFH-positive and BCFH-negative peers to report themselves at increased risk (P < .001). In all groups, perceived risk of breast cancer was associated with older age. Higher breast cancer-specific distress among adolescent girls was associated with higher self-perceived risk of breast cancer and higher maternal breast cancer-specific distress.

CONCLUSION

Adolescent girls from BRCA1/2-positive and breast cancer families have higher self-esteem and do not have poorer psychosocial adjustment than peers. However, they do experience greater breast cancer-specific distress and perceived risk of breast cancer, particularly among older girls. Understanding the impact is important to optimize responses to growing up in families at familial and genetic risk for breast cancer, particularly given the debate over the genetic testing of children for cancer susceptibility in adulthood.

Adolescent fiber intake and mammographic breast density in premenopausal women

Background

To date, there is limited and inconsistent epidemiologic evidence for associations of adolescent diet with mammographic breast density, a strong and consistent predictor of breast cancer. We investigated the association of adolescent fiber intake with mammographic density in premenopausal women.

Methods

This study included 743 cancer-free premenopausal women (mean age, 44.9 years) within the Nurses’ Health Study II cohort. Percent breast density, absolute dense and non-dense areas were measured from digitized film mammograms using a computer-assisted thresholding technique. Adolescent and adult diet were assessed with a food frequency questionnaire; energy-adjusted nutrient intakes were estimated for each food item. Information regarding breast cancer risk factors was obtained from baseline or biennial questionnaires closest to the mammogram date. We used generalized linear regression to quantify associations between quartiles of adolescent fiber intake and each of the breast density measures, adjusted for potential confounders. Associations were examined separately for total fiber intake; fiber from fruits, vegetables, legumes, and cereal; and food sources of fiber (fruits, vegetables, and nuts).

Results

In multivariable analyses, total fiber intake during adolescence was not associated with percent breast density (p for trend = 0.64), absolute dense area (p for trend = 0.80), or non-dense area (p for trend = 0.75). Similarly, neither consumption of fiber from fruits, vegetables, legumes, or cereal nor specific sources of fiber intake (fruits, vegetables, or nuts) during adolescence were associated with any of the mammographic density phenotypes.

Conclusions

Our findings do not support the hypothesis that adolescent fiber intake is associated with premenopausal mammographic breast density.

Effects of Pubertal Exposure to Dietary Soy on Estrogen Receptor Activity in the Breast of Cynomolgus Macaques

Endogenous estrogens influence mammary gland development during puberty and breast cancer risk during adulthood. Early-life exposure to dietary or environmental estrogens may alter estrogen-mediated processes. Soy foods contain phytoestrogenic isoflavones (IF), which have mixed estrogen agonist/antagonist properties. Here, we evaluated mammary gland responses over time in pubertal female cynomolgus macaques fed diets containing either casein/lactalbumin (n = 12) or soy protein containing a human-equivalent dose of 120 mg IF/day (n = 17) for approximately 4.5 years spanning menarche. We assessed estrogen receptor (ER) expression and activity, promoter methylation of ERs and their downstream targets, and markers of estrogen metabolism. Expression of ERα and classical ERα response genes (TFF1, PGR, and GREB1) decreased with maturity, independent of diet. A significant inverse correlation was observed between TFF1 mRNA and methylation of CpG sites within the TFF1 promoter. Soy effects included lower ERβ expression before menarche and lower mRNA for ERα and GREB1 after menarche. Expression of GATA-3, an epithelial differentiation marker that regulates ERα-mediated transcription, was elevated before menarche and decreased after menarche in soy-fed animals. Soy did not significantly alter expression of other ER activity markers, estrogen-metabolizing enzymes, or promoter methylation for ERs or ER-regulated genes. Our results demonstrate greater ER expression and activity during the pubertal transition, supporting the idea that this life stage is a critical window for phenotypic modulation by estrogenic compounds. Pubertal soy exposure decreases mammary ERα expression after menarche and exerts subtle effects on receptor activity and mammary gland differentiation. Cancer Prev Res; 9(5); 385-95. ©2016 AACR.

The LEGACY Girls Study: Growth and Development in the Context of Breast Cancer Family History

BACKGROUND

Although the timing of pubertal milestones has been associated with breast cancer risk, few studies of girls' development include girls at increased breast cancer risk due to their family history.

METHODS

The Lessons in Epidemiology and Genetics of Adult Cancer from Youth (LEGACY) Girls Study was initiated in 2011 in the USA and Canada to assess the relation between early life exposures and intermediate markers of breast cancer risk (e.g., pubertal development, breast tissue characteristics) and to investigate psychosocial well being and health behaviors in the context of family history. We describe the methods used to establish and follow a cohort of 1,040 girls ages 6-13 years at baseline, half with a breast cancer family history, and the collection of questionnaire data (family history, early life exposures, growth and development, psychosocial and behavioral), anthropometry, biospecimens, and breast tissue characteristics using optical spectroscopy.

RESULTS

During this initial 5-year phase of the study, follow-up visits are conducted every 6 months for repeated data and biospecimen collection. Participation in baseline components was high (98% for urine, 97.5% for blood or saliva, and 98% for anthropometry). At enrollment, 77% of girls were premenarcheal and 49% were at breast Tanner stage T1.

CONCLUSIONS

This study design allows thorough examination of events affecting girls' growth and development and how they differ across the spectrum of breast cancer risk. A better understanding of early life breast cancer risk factors will be essential to enhance prevention across the lifespan for those with and without a family history of the disease.

Adolescent intake of animal fat and red meat in relation to premenopausal mammographic density

Adolescence is hypothesized to be a time period of particular susceptibility to breast cancer risk factors. Red meat and fat intake during high school was positively associated with risk of breast cancer among premenopausal women in the Nurses' Health Study II (NHSII). High mammographic density is a strong predictor of breast cancer risk but there is limited research on dietary factors associated with breast density. To test the hypothesis that high intake of animal fat or red meat during adolescence is associated with mammographic density, we analyzed data from premenopausal women in the NHSII. Participants recalled adolescent diet on a high school food frequency questionnaire. We assessed absolute and percent mammographic density on digitized analog film mammograms for 687 premenopausal women with no history of cancer. We used generalized linear regression to quantify associations of adolescent animal fat and red meat intake with mammographic density, adjusting for age, body mass index, and other predictors of mammographic density. Adolescent animal fat intake was significantly positively associated with premenopausal mammographic density, with a mean percent density of 39.2 % in the lowest quartile of adolescent animal fat intake versus 43.1 % in the highest quartile (p trend: 0.03). A non-significant positive association was also observed for adolescent red meat intake (p trend: 0.14). These findings suggest that higher adolescent animal fat intake is weakly associated with percent mammographic density in premenopausal women.

Puberty-specific promotion of mammary tumorigenesis by a high animal fat diet

INTRODUCTION

Increased animal fat consumption is associated with increased premenopausal breast cancer risk in normal weight, but not overweight, women. This agrees with our previous findings in obesity-resistant BALB/c mice, in which exposure to a high saturated animal fat diet (HFD) from peripuberty through adulthood promoted mammary tumorigenesis. Epidemiologic and animal studies support the importance of puberty as a life stage when diet and environmental exposures affect adult breast cancer risk. In this study, we identified the effects of peripubertal exposure to HFD and investigated its mechanism of enhancing tumorigenesis.

METHODS

Three-week-old BALB/c mice fed a low-fat diet (LFD) or HFD were subjected to 7,12-dimethylbenz[a]anthracene (DMBA)-induced carcinogenesis. At 9 weeks of age, half the mice on LFD were switched to HFD (LFD-HFD group) and half the mice on HFD were switched to LFD (HFD-LFD group). Tumor gene expression was evaluated in association with diet and tumor latency.

RESULTS

The peripubertal HFD reduced the latency of DMBA-induced mammary tumors and was associated with tumor characteristics similar to those in mice fed a continuous HFD. Notably, short-latency tumors in both groups shared gene expression characteristics and were more likely to have adenosquamous histology. Both HFD-LFD and continuous HFD tumors showed similar gene expression patterns and early latency. Adult switch from HFD to LFD did not reverse peripubertal HFD tumor promotion. Increased proliferation, hyperplasia, and macrophages were present in mammary glands before tumor development, implicating these as possible effectors of tumor promotion. Despite a significant interaction between pubertal diet and carcinogens in tumor promotion, peripubertal HFD by itself produced persistent macrophage recruitment to mammary glands.

CONCLUSIONS

In obesity-resistant mice, peripubertal HFD is sufficient to irreversibly promote carcinogen-induced tumorigenesis. Increased macrophage recruitment is likely a contributing factor. These results underscore the importance of early life exposures to increased adult cancer risk and are consistent with findings that an HFD in normal weight premenopausal women leads to increased breast cancer risk. Notably, short-latency tumors occurring after peripubertal HFD had characteristics similar to human basal-like breast cancers that predominantly develop in younger women.

Psychosocial Adjustment in School-age Girls With a Family History of Breast Cancer

OBJECTIVE

Understanding how young girls respond to growing up with breast cancer family histories is critical given expansion of genetic testing and breast cancer messaging. We examined the impact of breast cancer family history on psychosocial adjustment and health behaviors among >800 girls in the multicenter LEGACY Girls Study.

METHODS

Girls aged 6 to 13 years with a family history of breast cancer or familial BRCA1/2 mutation (BCFH+), peers without a family history (BCFH-), and their biological mothers completed assessments of psychosocial adjustment (maternal report for 6- to 13-year-olds, self-report for 10- to 13-year-olds), breast cancer-specific distress, perceived risk of breast cancer, and health behaviors (10- to 13-year-olds).

RESULTS

BCFH+ girls had better general psychosocial adjustment than BCFH- peers by maternal report. Psychosocial adjustment and health behaviors did not differ significantly by self-report among 10- to 13-year-old girls. BCFH+ girls reported higher breast cancer-specific distress (P = .001) and were more likely to report themselves at increased breast cancer risk than BCFH- peers (38.4% vs 13.7%, P < .001), although many girls were unsure of their risk. In multivariable analyses, higher daughter anxiety was associated with higher maternal anxiety and poorer family communication. Higher daughter breast cancer-specific distress was associated with higher maternal breast cancer-specific distress.

CONCLUSIONS

Although growing up in a family at risk for breast cancer does not negatively affect general psychosocial adjustment among preadolescent girls, those from breast cancer risk families experience greater breast cancer-specific distress. Interventions to address daughter and mother breast cancer concerns and responses to genetic or familial risk might improve psychosocial outcomes of teen daughters.

Vegetable protein and vegetable fat intakes in pre-adolescent and adolescent girls, and risk for benign breast disease in young women

Previous investigations, of adolescent diet recalled in adulthood, found lower risk for benign breast disease (BBD) with higher intakes of vegetable fat and nuts during high school. We investigate whether vegetable protein and fat, derived from diets reported during pre-adolescence and adolescence, are associated with subsequent risk for BBD in young women. The Growing Up Today Study includes 9,039 females, 9-15 years in 1996, who completed questionnaires annually through 2001, and then in 2003, 2005, 2007, and 2010. Food frequency questionnaires (1996-2001) obtained intake data on a variety of foods. Beginning in 2005, women (18-30 years) reported whether they had ever been diagnosed with BBD that was confirmed by breast biopsy (n = 112 cases). Logistic regression estimated associations between intakes of vegetable protein and fat and biopsy-confirmed BBD. Those individual foods that were the largest contributors of protein and fat in this cohort were also investigated. In analyses of intakes from 1996 through 1998, when our cohort was youngest, vegetable fat (OR = 0.72/(10 gm/day), 95 % CI 0.53-0.98; p = 0.04) was inversely associated with BBD risk. The greatest sources of vegetable fat and protein in these girls were peanut butter, peanuts, nuts, beans (beans, lentils, and soybeans), and corn. A daily serving of any one of these was associated with lower risk (OR = 0.32/(serv/day), 95 % CI 0.13-0.79; p = 0.01). Peanut butter (and nuts) at age 11 years was inversely associated with risk (p = 0.01). In analyses of intakes at age 14 years, vegetable protein was associated with lower BBD risk (OR = 0.64/(10 gm/day), 95 % CI 0.43-0.95; p = 0.03). A daily serving at 14 years of any one of the foods was associated with lower risk (OR = 0.34, 95 % CI 0.16-0.75; p = 0.01), as was peanut butter (and nuts) (p = 0.02). Girls with a family history of breast cancer had significantly lower risk if they consumed these foods or vegetable fat. In conclusion, consumption of vegetable protein, fat, peanut butter, or nuts by older girls may help reduce their risk of BBD as young women.

Invited commentary: are dietary intakes and other exposures in childhood and adolescence important for adult cancers?

In this issue of the Journal, Nimptsch et al. (Am J Epidemiol. 2013;178(2):172-183) report significant associations between female adolescents' poultry consumption in high school and subsequent reduced risk of colorectal adenomas in adulthood. Consumption of red meat or fish was not related to risk, but replacement with poultry reduced the risk of later adenomas. Most epidemiologic studies of adult diseases lack exposure data from the distant past. By focusing on a cancer precursor lesion and using a variety of methods to assess data quality, the investigators address concerns about the quality of distant recall. These findings add to the growing evidence that links childhood and adolescent lifestyle and environmental exposures with subsequent risk of cancers arising in adulthood. Highlights of the literature on this topic and methodological challenges are summarized. Future studies would benefit from incorporating measures of lifestyle, diet, environmental exposures, and other risk factors from early in life and from validation and other data quality checks of such measurements. Sources of historical data on children's and adolescents' exposures should be sought and evaluated in conjunction with subsequent exposures in relationship to adult-onset cancers.

Cancer prevention for the next generation

Given the continued growth in the number of persons with cancer in the United States, the primary prevention of cancer remains an urgent public health priority. As the field of cancer prevention continues to mature and scientific knowledge evolves, it is imperative to challenge the status quo and embrace new approaches to cancer prevention. In this commentary, we summarize recent trends and some of the scientific advances that have been made over the past few decades regarding the complex process of cancer development and the interaction of individual and social risk factors. We examine some of the assumptions and terminology that have characterized cancer prevention approaches for more than a quarter century and the impact of these assumptions and our use of terminology. We propose that it is possible for today's youth to experience lower cancer incidence rates as adults compared with previous generations. To accomplish this goal, a more transdisciplinary and multifaceted approach is needed, adapted as appropriate for different populations and stages of life. The greatest improvements in cancer prevention may occur as a result of innovative, multilevel interventions that build on the expanding scientific evidence base.