A Population-Based Study of Genes Previously Implicated in Breast Cancer.

BACKGROUND: Population-based estimates of the risk of breast cancer associated with germline pathogenic variants in cancer-predisposition genes are critically needed for risk assessment and management in women with inherited pathogenic variants. METHODS: In a population-based case-control study, we performed sequencing using a custom multigene amplicon-based panel to identify germline pathogenic variants in 28 cancer-predisposition genes among 32,247 women with breast cancer (case patients) and 32,544 unaffected women (controls) from population-based studies in the Cancer Risk Estimates Related to Susceptibility (CARRIERS) consortium. Associations between pathogenic variants in each gene and the risk of breast cancer were assessed. RESULTS: Pathogenic variants in 12 established breast cancer-predisposition genes were detected in 5.03% of case patients and in 1.63% of controls. Pathogenic variants in BRCA1 and BRCA2 were associated with a high risk of breast cancer, with odds ratios of 7.62 (95% confidence interval [CI], 5.33 to 11.27) and 5.23 (95% CI, 4.09 to 6.77), respectively. Pathogenic variants in PALB2 were associated with a moderate risk (odds ratio, 3.83; 95% CI, 2.68 to 5.63). Pathogenic variants in BARD1, RAD51C, and RAD51D were associated with increased risks of estrogen receptor-negative breast cancer and triple-negative breast cancer, whereas pathogenic variants in ATM, CDH1, and CHEK2 were associated with an increased risk of estrogen receptor-positive breast cancer. Pathogenic variants in 16 candidate breast cancer-predisposition genes, including the c.657_661del5 founder pathogenic variant in NBN, were not associated with an increased risk of breast cancer. CONCLUSIONS: This study provides estimates of the prevalence and risk of breast cancer associated with pathogenic variants in known breast cancer-predisposition genes in the U.S. population. These estimates can inform cancer testing and screening and improve clinical management strategies for women in the general population with inherited pathogenic variants in these genes. (Funded by the National Institutes of Health and the Breast Cancer Research Foundation.).

Adsorption of Cu (II) and Zn (II) in aqueous solution by modified bamboo charcoal.

Due to the development of industries such as mining, smelting, industrial electroplating, tanning, and mechanical manufacturing, heavy metals were discharged into water bodies seriously affecting water quality. Bamboo charcoal, as an environmentally friendly new adsorbent material, in this paper, the virgin bamboo charcoal (denoted as WBC) was modified with different concentrations of KMnO4 and NaOH to obtain KMnO4-modified bamboo charcoal (KBC) and NaOH-modified bamboo charcoal (NBC) which was used to disposed of water bodies containing Cu2+ and Zn2+. The main conclusions were as following: The adsorption of Cu2+ by WBC, KBC and NBC was significantly affected by pH value, and the optimum pH was 5.0. Differently, the acidity and alkalinity of the solution doesn't effect the adsorption of Zn2+ seriousely. Meanwhile, surface diffusion and pore diffusion jointly determine the adsorption rate of Cu2+ and Zn2+. The test result of EDS showed that Mn-O groups formed on the surface of K6 (WBC treated by 0.06 mol/L KMnO4) can promote the adsorption of Cu2+ and Zn2+ at a great degree. The O content on N6(WBC treated by 6 mol/L NaOH) surface increased by 30.95% compared with WBC. It is speculated that the increase of carbonyl group on the surface of NBC is one of the reasons for the improvement of Cu2+ and Zn2+ adsorption capacity. Finally, the residual concentrations of Cu2+ and Zn2+ in wastewater are much lower than 0.5 mg/L and 1.0 mg/L, respectively. Thus it can be seen, KBC and NBC could be a promising adsorbent for heavy metals.

A "Pre-Division Metal Clusters" Strategy to Mediate Efficient Dual-Active Sites ORR Catalyst for Ultralong Rechargeable Zn-Air Battery.

To conquer the bottleneck of sluggish kinetics in cathodic oxygen reduction reaction (ORR) of metal-air batteries, catalysts with dual-active centers have stood out. Here, a "pre-division metal clusters" strategy is firstly conceived to fabricate a N,S-dual doped honeycomb-like carbon matrix inlaid with CoN4 sites and wrapped Co2 P nanoclusters as dual-active centers (Co2 P/CoN4 @NSC-500). A crystalline {CoII 2 } coordination cluster divided by periphery second organic layers is well-designed to realize delocalized dispersion before calcination. The optimal Co2 P/CoN4 @NSC-500 executes excellent 4e- ORR activity surpassing the benchmark Pt/C. Theoretical calculation results reveal that the CoN4 sites and Co2 P nanoclusters can synergistically quicken the formation of *OOH on Co sites. The rechargeable Zn-air battery (ZAB) assembled by Co2 P/CoN4 @NSC-500 delivers ultralong cycling stability over 1742 hours (3484 cycles) under 5 mA cm-2 and can light up a 2.4 V LED bulb for ≈264 hours, evidencing the promising practical application potentials in portable devices.

The association of age at menarche and adult height with mammographic density in the International Consortium of Mammographic Density.

BACKGROUND: Early age at menarche and tall stature are associated with increased breast cancer risk. We examined whether these associations were also positively associated with mammographic density, a strong marker of breast cancer risk. METHODS: Participants were 10,681 breast-cancer-free women from 22 countries in the International Consortium of Mammographic Density, each with centrally assessed mammographic density and a common set of epidemiologic data. Study periods for the 27 studies ranged from 1987 to 2014. Multi-level linear regression models estimated changes in square-root per cent density (√PD) and dense area (√DA) associated with age at menarche and adult height in pooled analyses and population-specific meta-analyses. Models were adjusted for age at mammogram, body mass index, menopausal status, hormone therapy use, mammography view and type, mammographic density assessor, parity and height/age at menarche. RESULTS: In pooled analyses, later age at menarche was associated with higher per cent density (ß√PD = 0.023 SE = 0.008, P = 0.003) and larger dense area (ß√DA = 0.032 SE = 0.010, P = 0.002). Taller women had larger dense area (ß√DA = 0.069 SE = 0.028, P = 0.012) and higher per cent density (ß√PD = 0.044, SE = 0.023, P = 0.054), although the observed effect on per cent density depended upon the adjustment used for body size. Similar overall effect estimates were observed in meta-analyses across population groups. CONCLUSIONS: In one of the largest international studies to date, later age at menarche was positively associated with mammographic density. This is in contrast to its association with breast cancer risk, providing little evidence of mediation. Increased height was also positively associated with mammographic density, particularly dense area. These results suggest a complex relationship between growth and development, mammographic density and breast cancer risk. Future studies should evaluate the potential mediation of the breast cancer effects of taller stature through absolute breast density.

Unraveling the Mechanism of Aerobic Alcohol Oxidation by a Cu/pytl-ß-Cyclodextrin/TEMPO Catalytic System under Air in Neat Water.

The mechanism for the oxidation of p-tolylmethanol to p-tolualdehyde catalyzed by a Cu/pytl-ß-cyclodextrin/TEMPO (TEMPO = 2,2,6,6-tetramethylpiperidinyl-1-oxy) catalytic system under air in neat water is fully investigated by density functional theory (DFT). Four possible pathways (paths A → D) are presented. The calculated TOF = 0.67 h-1 for path A is consistent with the experimental TOF = 1.9 h-1 but much lower than that for path D (TOF = 1.1 × 105 h-1). The results demonstrate that path A is the dominant pathway under the optimal experimental conditions, even though path D is more kinetically favorable. This is because the concentration of precatalyst 11 [(pytl-ß-CD)CuII(OH)] in path D is too low to start path D, so p-tolylmethanol oxidation can only proceed via path A. This finding implies that the relative concentration of precatalysts in a one-pot synthesis experiment plays a vital role in the aerobic alcohol oxidation reaction. Based on this finding, we speculate that the direct use of the presynthesized precatalyst 11 or addition of an appropriate amount of NaOH to the reaction solution, but with the total amount of the base added unchanged, is a good way to improve its catalytic activity. Meanwhile, the solvent water was not found to directly participate in the catalytic active sites for the oxidation of alcohols but rather inhibited it by forming the hydrogen-bonded network.

Nanocage-Based N-Rich Metal-Organic Framework for Luminescence Sensing toward Fe3+ and Cu2+ Ions.

Luminescent metal-organic frameworks (LMOFs) as sensors showing highly efficient detection toward toxic heavy-metal ions are in high demand for human health and environmental protection. A novel nanocage-based N-rich LMOF (LCU-103) has been constructed and characterized. It is a 2-fold interpenetrating structure built from N-rich {Zn6(dttz)4} nanocages extended by N-donor ligand Hdpa [H3dttz = 4,5-di(1H-tetrazol-5-yl)-2H-1,2,3-triazole; Hdpa = 4,4'-dipyridylamine]. Notably, LCU-103 contains abundant N functional sites anchoring on both the windows of nanocages and the inner channels of the framework that can interact with metal ions and then recognize them. As a result, it can serve as a luminescent sensing material for detecting trace amounts of Fe3+ and Cu2+ ions with low limits of detection (LODs) of 1.45 and 1.66 µM, respectively, through a luminescent quenching mechanism. Meanwhile, LCU-103 as a LMOF sensor exhibits several advantages such as high sensitivity, appropriate selectivity (for Fe3+ in H2O), recycling stability, and fast response times in N,N-dimethylformamide. Moreover, LCU-103 also displays good luminescent quenching activity toward Fe3+ in H2O and a simulated 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid biological system with low LODs of 1.51 and 1.52 µM, respectively. LCU-103 test papers were further prepared to offer easy and real-time detection of Fe3+ and Cu2+ ions. Importantly, when density functional theory calculations and multiple experimental evidence, including X-ray photoelectron spectroscopy, UV-vis absorption, luminescence decay lifetimes, and quantum efficiencies, are combined, a preferred N-donor site and possible weak interaction sensing mechanism is also proposed to elucidate the quenching effect.

Adult weight change and premenopausal breast cancer risk: A prospective pooled analysis of data from 628,463 women.

Early-adulthood body size is strongly inversely associated with risk of premenopausal breast cancer. It is unclear whether subsequent changes in weight affect risk. We pooled individual-level data from 17 prospective studies to investigate the association of weight change with premenopausal breast cancer risk, considering strata of initial weight, timing of weight change, other breast cancer risk factors and breast cancer subtype. Hazard ratios (HR) and 95% confidence intervals (CI) were obtained using Cox regression. Among 628,463 women, 10,886 were diagnosed with breast cancer before menopause. Models adjusted for initial weight at ages 18-24 years and other breast cancer risk factors showed that weight gain from ages 18-24 to 35-44 or to 45-54 years was inversely associated with breast cancer overall (e.g., HR per 5 kg to ages 45-54: 0.96, 95% CI: 0.95-0.98) and with oestrogen-receptor(ER)-positive breast cancer (HR per 5 kg to ages 45-54: 0.96, 95% CI: 0.94-0.98). Weight gain from ages 25-34 was inversely associated with ER-positive breast cancer only and weight gain from ages 35-44 was not associated with risk. None of these weight gains were associated with ER-negative breast cancer. Weight loss was not consistently associated with overall or ER-specific risk after adjusting for initial weight. Weight increase from early-adulthood to ages 45-54 years is associated with a reduced premenopausal breast cancer risk independently of early-adulthood weight. Biological explanations are needed to account for these two separate factors.

Associations between nutritional factors and chemotherapy toxicity in older adults with solid tumors.

BACKGROUND: Nutritional status can directly affect morbidity and mortality in older adults with cancer. This study evaluated the association between pretreatment body mass index (BMI), albumin level, and unintentional weight loss (UWL) in the prior 6 months and chemotherapy toxicity among older adults with solid tumors. METHODS: This was a secondary analysis of a prospective, multicenter study involving chemotherapy-treated patients 65 years old or older. Geriatric assessment, BMI, albumin level, and UWL data were collected before treatment. Multivariable logistic regression models evaluated the associations between nutritional factors and the risk of grade 3 or higher (grade 3+) chemotherapy toxicity. RESULTS: Seven hundred fifty patients with a median age of 72 years (range, 65-94 years) and mostly stage IV disease were enrolled. The median pretreatment BMI and albumin values were 26 kg/m2 (range, 15.1-52.1 kg/m2 ) and 3.9 mg/dL (range, 1.0-5.0 mg/dL), respectively. Nearly 50% of the patients reported UWL, with 17.6% reporting >10% UWL. Multivariable analysis revealed no association between >10% UWL and a risk for grade 3+ chemotherapy toxicity (adjusted odds ratio [AOR], 0.87; P = .58). Multivariable analysis showed a trend toward an association between a BMI ≥ 30 kg/m2 and a decreased risk of grade 3+ chemotherapy toxicity (AOR, 0.65; P = .06), whereas a low albumin level (≤3.6 mg/dL) was associated with a higher risk of grade 3+ chemotherapy toxicity (AOR, 1.50; P = .03). An analysis of the joint effect of BMI and albumin demonstrated the lowest risk of grade 3+ chemotherapy toxicity among patients with high BMIs (≥30 kg/m2 ) and normal albumin levels (AOR, 0.41; P = .008). CONCLUSIONS: Among older adults with solid tumors, higher BMIs and normal albumin levels are associated with a lower risk of grade 3+ chemotherapy toxicity. Additional research is warranted to define the clinical significance of nutritional markers and to inform future interventions.

Structural Diversity of Copper(I) Cluster-Based Coordination Polymers with Pyrazine-2-thiol Ligand.

Six novel copper(I) cluster-based coordination polymers (CPs) [Cu9(pzt)7Cl2]n (1), [Cu2(pzt)Cl]n (2), [Cu4(pzt)3Br]n (3), [Cu(pzt)]n (4), [Cu4(pzt)3I]n (5), and [Cu7(pzt)6I]n (6) were solvothermally synthesized using Hpzt (Hpzt = pyrazine-2-thiol) ligand and well-characterized by elemental analysis, infrared (IR) spectroscopy, powder X-ray diffraction (PXRD), and single-crystal X-ray diffraction (SCXRD). Six CPs exhibit either 2D (4 and 6) or 3D (1-3, and 5) network based on diverse multinuclear {CuxSy} clusters. The structural evolutions of 1-6 are greatly influenced by types of metal halides and the ligand-to-metal molar ratio used in the reaction. Among them, compound 1 displays interesting temperature-dependent photoluminescence arising from triplet cluster-centered (3CC) excited state from the cluster metal core. Compounds 1-6 also exhibit photocurrent responses upon visible-light illumination (λ = 420 nm) in the order 6 > 5 > 3 > 1 > 4 > 2. This work not only shows the structural diversity of {CuxSy} clusters-based CPs but also provides an interesting insight into structural modulation using crystal engineering concept.

Intrinsic brain activity changes associated with adjuvant chemotherapy in older women with breast cancer: a pilot longitudinal study.

PURPOSE: Older cancer patients are at increased risk of cancer-related cognitive impairment. The purpose of this study was to assess the alterations in intrinsic brain activity associated with adjuvant chemotherapy in older women with breast cancer. METHODS: Chemotherapy treatment (CT) group included sixteen women aged ≥ 60 years (range 60-82 years) with stage I-III breast cancers, who underwent both resting-state functional magnetic resonance imaging (rs-fMRI) and neuropsychological testing with NIH Toolbox for Cognition before adjuvant chemotherapy, at time point 1 (TP1), and again within 1 month after completing chemotherapy, at time point 2 (TP2). Fourteen age- and sex-matched healthy controls (HC) underwent the same assessments at matched intervals. Three voxel-wise rs-fMRI parameters: amplitude of low-frequency fluctuation (ALFF), fractional ALFF (fALFF), and regional homogeneity, were computed at each time point. The changes in rs-fMRI parameters from TP1 to TP2 for each group, the group differences in changes (the CT group vs. the HC group), and the group difference in the baseline rs-fMRI parameters were assessed. In addition, correlative analysis between the rs-fMRI parameters and neuropsychological testing scores was also performed. RESULTS: In the CT group, one brain region, which included parts of the bilateral subcallosal gyri and right anterior cingulate gyrus, displayed increased ALFF from TP1 to TP2 (cluster p-corrected = 0.024); another brain region in the left precuneus displayed decreased fALFF from TP1 to TP2 (cluster level p-corrected = 0.025). No significant changes in the rs-fMRI parameters from TP1 to TP2 were observed in the HC group. Although ALFF and fALFF alterations were observed only in the CT group, none of the between-group differences in rs-fMRI parameter changes reached statistical significance. CONCLUSIONS: Our study results of ALFF and fALFF alterations in the chemotherapy-treated women suggest that adjuvant chemotherapy may affect intrinsic brain activity in older women with breast cancer.

Pre-diagnosis alcohol consumption and mortality risk among black women and white women with invasive breast cancer.

BACKGROUND: Alcohol consumption is associated with increased risk of breast cancer; however, its association with subsequent risk of breast cancer death is unclear. METHODS: We followed 4523 women with complete information on relevant risk factors for mortality; these women were 35 to 64 years of age when diagnosed with incident invasive breast cancer between 1994 and 1998. During follow up (median, 8.6 years), 1055 women died; 824 died from breast cancer. The information on alcohol consumption before diagnosis was collected shortly after breast cancer diagnosis (average: 5.1 months) during an in-person interview which used a structured questionnaire. Multivariable Cox proportional hazards regression models provided hazard ratios (HRs) and 95% confidence intervals (CIs) for breast cancer-specific mortality, mortality due to causes other than breast cancer, and all-cause mortality associated with alcohol consumption from age 15 years until breast cancer diagnosis and during recent periods of time prior to breast cancer diagnosis. RESULTS: Average weekly alcohol consumption from age 15 years until breast cancer diagnosis was inversely associated with breast cancer-specific mortality (Ptrend = 0.01). Compared to non-drinkers, women in the highest average weekly alcohol consumption category (≥7 drinks/week) had 25% lower risk of breast cancer-specific mortality (HR = 0.75, 95% CI = 0.56-1.00). Breast cancer mortality risk was also reduced among women in the highest average weekly alcohol consumption category in two recent time periods (5-year period ending 2-years prior to breast cancer diagnosis, HR = 0.74, 95% CI = 0.57-0.95; 2-year period immediately prior to breast cancer diagnosis: HR = 0.73, 95% CI = 0.56-0.95). Furthermore, analyses of average weekly alcohol consumption by beverage type from age 15 years until breast cancer diagnosis suggested that wine consumption was inversely associated with breast cancer-specific mortality risk (wine Ptrend = 0.06, beer Ptrend = 0.24, liquor Ptrend = 0.74). No association with any of these alcohol consumption variables was observed for mortality risk due to causes other than breast cancer. CONCLUSIONS: Overall, we found no evidence that alcohol consumption before breast cancer diagnosis increases subsequent risk of death from breast cancer.

Body mass index at age 18 years and recent body mass index in relation to risk of breast cancer overall and ER/PR/HER2-defined subtypes in white women and African-American women: a pooled analysis.

BACKGROUND: Although it has been well-documented that obesity is associated with decreased risk of premenopausal breast cancer and increased risk of postmenopausal breast cancer, it is unclear whether these associations differ among breast cancer subtypes defined by the tumor protein expression status of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2). METHODS: We evaluated the associations of body mass index (BMI) at age 18 years and recent BMI in relation to risk of breast cancer overall and ER/PR/HER2-defined subtypes, in 6320 women (3934 case-patient participants, 2386 control participants) aged 35-64 years, who participated in one of three population-based case-control studies. We estimated multivariable-adjusted odd ratios (ORs) and corresponding 95% confidence intervals (CIs) using polychotomous unconditional logistic regression methods for case-control comparisons in premenopausal women and postmenopausal women. RESULTS: BMI at age 18 years was inversely associated with risk of breast cancer, particularly among premenopausal women (≥ 25 vs. < 20 kg/m2, OR = 0.72, 95% CI = 0.53-0.96; per 5 kg/m2 increase, OR = 0.83, 95% CI = 0.73-0.95). This inverse association did not differ across ER/PR/HER2-defined subtypes or by race (white women, African-American women). Recent BMI was not associated with risk of premenopausal breast cancer after adjustment for BMI at age 18 years; nevertheless, the analysis for the joint effects of BMI at age 18 years and recent BMI showed that premenopausal women in the highest categories of the two BMI measures (≥ 25 kg/m2 at age 18 years and ≥ 30 kg/m2 for recent BMI) had 46% lower risk of breast cancer than premenopausal women in the lowest categories of the two BMI measures (< 20 kg/m2 at age 18 years and < 25 kg/m2 for recent BMI; OR = 0.54, 95% CI = 0.38-0.78). Neither measure of BMI was statistically significantly associated with risk of postmenopausal breast cancer. CONCLUSION: Our findings indicate that high BMI near the end of adolescence decreases risk of all ER/PR/HER2-defined subtypes of premenopausal breast cancer and also suggest that this benefit could be maximized among premenopausal women who consistently have high BMI during their premenopausal years.

Gray matter density reduction associated with adjuvant chemotherapy in older women with breast cancer.

PURPOSE: The purpose of this study was to evaluate longitudinal changes in brain gray matter density (GMD) before and after adjuvant chemotherapy in older women with breast cancer. METHODS: We recruited 16 women aged ≥ 60 years with stage I-III breast cancers receiving adjuvant chemotherapy (CT) and 15 age- and sex-matched healthy controls (HC). The CT group underwent brain MRI and the NIH Toolbox for Cognition testing prior to adjuvant chemotherapy (time point 1, TP1) and within 1 month after chemotherapy (time point 2, TP2). The HC group underwent the same assessments at matched intervals. GMD was evaluated with the voxel-based morphometry. RESULTS: The mean age was 67 years in the CT group and 68.5 years in the HC group. There was significant GMD reduction within the chemotherapy group from TP1 to TP2. Compared to the HC group, the CT group displayed statistically significantly greater GMD reductions from TP1 to TP2 in the brain regions involving the left anterior cingulate gyrus, right insula, and left middle temporal gyrus (pFWE(family-wise error)-corrected < 0.05). The baseline GMD in left insula was positively correlated with the baseline list-sorting working memory score in the HC group (pFWE-corrected < 0.05). No correlation was observed for the changes in GMD with the changes in cognitive testing scores from TP1 to TP2 (pFWE-corrected < 0.05). CONCLUSIONS: Our findings indicate that GMD reductions were associated with adjuvant chemotherapy in older women with breast cancer. Future studies are needed to understand the clinical significance of the neuroimaging findings. This study is registered on ClinicalTrials.gov (NCT01992432).

Trajectories in Leisure-Time Physical Activity and Risk of Stroke in Women in the California Teachers Study.

BACKGROUND AND PURPOSE: Whether changes in leisure-time physical activity (LTPA) over time are associated with lower risk of stroke is not well established. We examined the association between changes in self-reported LTPA 10 years apart, with risk of incident stroke in the CTS (California Teachers Study). We hypothesized that the risk of stroke would be lowest among those who remained active. METHODS: Sixty-one thousand two hundred and fifty-six CTS participants reported LTPA at 2 intensity levels (moderate and strenuous activity) at 2 time points (baseline 1995-96; 10-year follow-up 2005-2006). LTPA at each intensity level was categorized based on American Heart Association (AHA) recommendations (moderate, >150 minutes/week; strenuous, >75 minutes/week). Changes in LTPA were summarized as follows: (1) not meeting recommendations at both time points; (2) meeting recommendations only at follow-up; (3) meeting recommendations only at baseline; and (4) meeting recommendations at both time points. Incident strokes were identified through California state hospitalization records. Using multivariable Cox models, we examined the associations between changes in LTPA with incident stroke. RESULTS: Nine hundred and eighty-seven women were diagnosed with stroke who completed both questionnaires. Meeting AHA recommendations at both the time points was associated with a lower risk of all stroke (adjusted hazard ratio, 0.84; 95% confidence interval, 0.72-0.98). The protective effects for stroke were driven by meeting AHA recommendations for moderate activity and largely observed for ischemic strokes (adjusted hazard ratio, 0.70; 95% confidence interval, 0.55-0.88). CONCLUSIONS: Meeting AHA recommendations for moderate activity had a protective effect for reducing ischemic stroke risk. Participants who met AHA recommendations at baseline but not at follow-up, however, were not afforded reduced stroke risk.

Reproductive factors and the risk of triple-negative breast cancer in white women and African-American women: a pooled analysis.

BACKGROUND: Early age at menarche, nulliparity, late age at first completed pregnancy, and never having breastfed, are established breast cancer risk factors. However, among breast cancer subtypes, it remains unclear whether all of these are risk factors for triple-negative breast cancer (TNBC). METHODS: We evaluated the associations of these reproductive factors with TNBC, in 2658 patients with breast cancer (including 554 with TNBC) and 2448 controls aged 20-64 years, who participated in one of the three population-based case-control studies: the Women's Contraceptive and Reproductive Experiences Study, the Women's Breast Carcinoma in situ Study, or the Women's Learning the Influence of Family and Environment Study. We used multivariable polychotomous unconditional logistic regression methods to conduct case-control comparisons among breast cancer subtypes defined by estrogen receptor, progesterone receptor, and human epidermal growth factor receptor-2 expression status. RESULTS: TNBC risk decreased with increasing duration of breastfeeding (P trend = 0.006), but age at menarche, age at first completed pregnancy, and nulliparity were not associated with risk of TNBC. Parous women who breastfed for at least one year had a 31% lower risk of TNBC than parous women who had never breastfed (odds ratio, OR = 0.69; 95% confidence interval, CI = 0.50-0.96). The association between breastfeeding and risk of TNBC was modified by age and race. Parous African-American women aged 20-44 years who breastfed for 6 months or longer had an 82% lower risk of TNBC than their counterparts who had never breastfed (OR = 0.18, 95% CI = 0.07-0.46). CONCLUSIONS: Our data indicate that breastfeeding decreases the risk of TNBC, especially for younger African-American women.

Mammographic density and ageing: A collaborative pooled analysis of cross-sectional data from 22 countries worldwide.

BACKGROUND: Mammographic density (MD) is one of the strongest breast cancer risk factors. Its age-related characteristics have been studied in women in western countries, but whether these associations apply to women worldwide is not known. METHODS AND FINDINGS: We examined cross-sectional differences in MD by age and menopausal status in over 11,000 breast-cancer-free women aged 35-85 years, from 40 ethnicity- and location-specific population groups across 22 countries in the International Consortium on Mammographic Density (ICMD). MD was read centrally using a quantitative method (Cumulus) and its square-root metrics were analysed using meta-analysis of group-level estimates and linear regression models of pooled data, adjusted for body mass index, reproductive factors, mammogram view, image type, and reader. In all, 4,534 women were premenopausal, and 6,481 postmenopausal, at the time of mammography. A large age-adjusted difference in percent MD (PD) between post- and premenopausal women was apparent (-0.46 cm [95% CI: -0.53, -0.39]) and appeared greater in women with lower breast cancer risk profiles; variation across population groups due to heterogeneity (I2) was 16.5%. Among premenopausal women, the √PD difference per 10-year increase in age was -0.24 cm (95% CI: -0.34, -0.14; I2 = 30%), reflecting a compositional change (lower dense area and higher non-dense area, with no difference in breast area). In postmenopausal women, the corresponding difference in √PD (-0.38 cm [95% CI: -0.44, -0.33]; I2 = 30%) was additionally driven by increasing breast area. The study is limited by different mammography systems and its cross-sectional rather than longitudinal nature. CONCLUSIONS: Declines in MD with increasing age are present premenopausally, continue postmenopausally, and are most pronounced over the menopausal transition. These effects were highly consistent across diverse groups of women worldwide, suggesting that they result from an intrinsic biological, likely hormonal, mechanism common to women. If cumulative breast density is a key determinant of breast cancer risk, younger ages may be the more critical periods for lifestyle modifications aimed at breast density and breast cancer risk reduction.

Recreational physical activity and risk of triple negative breast cancer in the California Teachers Study.

BACKGROUND: Evidence has accumulated showing that recreational physical activity reduces breast cancer risk. However, it is unclear whether risk reduction pertains to specific receptor-defined subtypes. Moreover, few studies have examined whether changes in the amount of recreational physical activity during adulthood influence breast cancer risk. METHODS: A total of 108,907 women, ages 22 to 79 years with no history of breast cancer when joining the California Teachers Study in 1995-1996, completed a baseline questionnaire and were eligible for the study. Through 2012, 5882 women were diagnosed with invasive breast cancer. Breast cancer subtypes were defined by the expression status of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2). Multivariable Cox proportional hazards models provided adjusted hazard ratios (HRs) and 95 % confidence intervals (CIs) for breast cancer overall and ER/PR/HER2-defined subtypes associated with long-term (from high school through age 54 or age at cohort entry, whichever was younger) and baseline (during 3 years prior to baseline) recreational physical activity. Among women who also completed a follow-up questionnaire at 10 years after baseline in 2005-2008 (54,686 women, 1406 with invasive breast cancer), risk associated with changes in the amount of recreational physical activity from baseline to the 10-year follow-up (during 3 years prior to the 10-year follow-up) was determined. RESULTS: Both long-term and baseline strenuous recreational physical activity were inversely associated with risk of invasive breast cancer (P trend ≤0.03). The observed associations were mainly confined to women with triple negative breast cancer (TNBC, ER-/PR-/HER2-, P trend ≤0.02) or luminal A-like subtype (ER+ or PR+ plus HER2-) who were former users of menopausal hormone therapy at baseline (P trend = 0.02, P homogeneity of trends ≤0.03). Moreover, women who consistently engaged in the highest level (≥3.51 h/wk/y) of strenuous recreational physical activity between baseline and 10-year follow-up had the lowest risk of breast cancer (HR = 0.71, 95 % CI = 0.52-0.98) when compared to those who were consistently low (≤0.50 h/wk/y). CONCLUSIONS: Strenuous recreational physical activity is associated with lower breast cancer risk, especially TNBC. The benefit may be maximized by consistently engaging in high-intensity recreational physical activity during adulthood.

Mammographic density assessed on paired raw and processed digital images and on paired screen-film and digital images across three mammography systems.

BACKGROUND: Inter-women and intra-women comparisons of mammographic density (MD) are needed in research, clinical and screening applications; however, MD measurements are influenced by mammography modality (screen film/digital) and digital image format (raw/processed). We aimed to examine differences in MD assessed on these image types. METHODS: We obtained 1294 pairs of images saved in both raw and processed formats from Hologic and General Electric (GE) direct digital systems and a Fuji computed radiography (CR) system, and 128 screen-film and processed CR-digital pairs from consecutive screening rounds. Four readers performed Cumulus-based MD measurements (n = 3441), with each image pair read by the same reader. Multi-level models of square-root percent MD were fitted, with a random intercept for woman, to estimate processed-raw MD differences. RESULTS: Breast area did not differ in processed images compared with that in raw images, but the percent MD was higher, due to a larger dense area (median 28.5 and 25.4 cm2 respectively, mean √dense area difference 0.44 cm (95% CI: 0.36, 0.52)). This difference in √dense area was significant for direct digital systems (Hologic 0.50 cm (95% CI: 0.39, 0.61), GE 0.56 cm (95% CI: 0.42, 0.69)) but not for Fuji CR (0.06 cm (95% CI: -0.10, 0.23)). Additionally, within each system, reader-specific differences varied in magnitude and direction (p < 0.001). Conversion equations revealed differences converged to zero with increasing dense area. MD differences between screen-film and processed digital on the subsequent screening round were consistent with expected time-related MD declines. CONCLUSIONS: MD was slightly higher when measured on processed than on raw direct digital mammograms. Comparisons of MD on these image formats should ideally control for this non-constant and reader-specific difference.

Novel polymorphisms in caspase-8 are associated with breast cancer risk in the California Teachers Study.

BACKGROUND: The ability of tamoxifen and raloxifene to decrease breast cancer risk varies among different breast cancer subtypes. It is important to determine one's subtype-specific breast cancer risk when considering chemoprevention. A number of single nucleotide polymorphisms (SNPs), including one in caspase-8 (CASP8), have been previously associated with risk of developing breast cancer. Because caspase-8 is an important protein involved in receptor-mediated apoptosis whose activity is affected by estrogen, we hypothesized that additional SNPs in CASP8 could be associated with breast cancer risk, perhaps in a subtype-specific manner. METHODS: Twelve tagging SNPs of CASP8 were analyzed in a nested case control study (1,353 cases and 1,384 controls) of non-Hispanic white women participating in the California Teachers Study. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated for each SNP using all, estrogen receptor (ER)-positive, ER-negative, human epidermal growth factor receptor 2 (HER2)-positive, and HER2-negative breast cancers as separate outcomes. RESULTS: Several SNPs were associated with all, ER-positive, and HER2-positive breast cancers; however, after correcting for multiple comparisons (i.e., p < 0.0008), only rs2293554 was statistically significantly associated with HER2-positive breast cancer (OR = 1.98, 95% CI 1.34-2.92, uncorrected p = 0.0005). CONCLUSIONS: While our results for CASP8 SNPs should be validated in other cohorts with subtype-specific information, we conclude that some SNPs in CASP8 are associated with subtype-specific breast cancer risk. This study contributes to our understanding of CASP8 SNPs and breast cancer risk by subtype.

A novel method for the synthesis of BiOCl/Bi2Sn2O7 heterojunction photocatalysts with enhanced visible light photocatalytic properties.

A novel simple method was proposed to synthesize BiOCl/Bi2Sn2O7 heterojunction photocatalysts through the treatment of Bi2Sn2O7 with HCl solution of different concentrations. The as-synthesized photocatalysts were characterized by x-ray diffraction, scanning electron microscopy, transmission electron microscopy, photoluminescence, x-ray photoelectron spectroscopy and ultraviolet-visible diffuse reflectance spectroscopy. The experimental results show that sheet-like BiOCl particles were obtained after the HCl treatment. Bi2Sn2O7 nanoparticles were distributed on the BiOCl sheets, resulting in the low aggregation of the Bi2Sn2O7 nanoparticles. As compared to BiOCl and Bi2Sn2O7, BiOCl/Bi2Sn2O7 showed enhanced photocatalytic activity under visible light irradiation, which can be attributed to the effective separation of photogenerated electrons and holes due to the formation of a BiOCl/Bi2Sn2O7 heterojunction. In addition, the dominant active species and the photocatalytic mechanism were discussed in detail.