Collaborative Molecular Epidemiology Study of Metabolic Dysregulation, DNA Methylation, and Breast Cancer Risk Among Nigerian Women: MEND Study Objectives and Design

PURPOSE To elucidate the role of metabolic dysregulation and associated DNA methylation changes on breast cancer risk and aggressive subtypes among Nigerian women. We describe the design and methods of a collaborative molecular epidemiology study of breast cancer in Nigerian hospitals. METHODS The Mechanisms for Novel and Established Risk Factors for Breast Cancer in Women of Nigerian Descent (MEND) study was designed as a matched case-control study of 350 patients, age 18 to 75 years, with newly diagnosed, treatment-naive breast cancer and 350 age-matched healthy controls from surrounding geographic areas. Patients with breast cancer seen for initial diagnosis at four large tertiary hospitals in southwest Nigeria and one affiliated private hospital were recruited. Healthy female controls were selected from a cohort of 4,000 healthy women recruited as part of the Human Heredity and Health (H3) in Africa Chronic Kidney Disease Case-Control Study in Nigeria. Tumor and adjacent normal tissue, and blood and saliva samples were collected for molecular and epigenetic assays. RESULTS Although recruitment is ongoing, a total of 416 patients have been recruited to date, with tumor and blood samples obtained from at least 310 patients. Data on age-matched (6 months) controls have also been obtained and harmonized. Lipid assays for 350 pathologically verified cases and 350 age-matched controls is underway, and pathologic characterization of tumors (including immunohistochemistry for subtyping) is ongoing. Data on DNA methylation for tumors and adjacent normal tissue are expected by the end of the study period. CONCLUSION The MEND study will provide a unique, high-quality source of data to evaluate the contribution of metabolic dysregulation such as obesity, diabetes, hypertension, and metabolic syndrome to the biology of breast cancer among Nigerian women and foster collaborative studies relevant for women of African descent globally. J Global Oncol. (C) 2019 by American Society of Clinical Oncology.National Institutes of Health, National Cancer Institute, Fogarty International Center [K01TW010271]Open access journalThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]

Collaborative Molecular Epidemiology Study of Metabolic Dysregulation, DNA Methylation, and Breast Cancer Risk Among Nigerian Women: MEND Study Objectives and Design

PURPOSE To elucidate the role of metabolic dysregulation and associated DNA methylation changes on breast cancer risk and aggressive subtypes among Nigerian women. We describe the design and methods of a collaborative molecular epidemiology study of breast cancer in Nigerian hospitals. METHODS The Mechanisms for Novel and Established Risk Factors for Breast Cancer in Women of Nigerian Descent (MEND) study was designed as a matched case-control study of 350 patients, age 18 to 75 years, with newly diagnosed, treatment-naïve breast cancer and 350 age-matched healthy controls from surrounding geographic areas. Patients with breast cancer seen for initial diagnosis at four large tertiary hospitals in southwest Nigeria and one affiliated private hospital were recruited. Healthy female controls were selected from a cohort of 4,000 healthy women recruited as part of the Human Heredity and Health (H3) in Africa Chronic Kidney Disease Case-Control Study in Nigeria. Tumor and adjacent normal tissue, and blood and saliva samples were collected for molecular and epigenetic assays. RESULTS Although recruitment is ongoing, a total of 416 patients have been recruited to date, with tumor and blood samples obtained from at least 310 patients. Data on age-matched (± 6 months) controls have also been obtained and harmonized. Lipid assays for 350 pathologically verified cases and 350 age-matched controls is underway, and pathologic characterization of tumors (including immunohistochemistry for subtyping) is ongoing. Data on DNA methylation for tumors and adjacent normal tissue are expected by the end of the study period. CONCLUSION The MEND study will provide a unique, high-quality source of data to evaluate the contribution of metabolic dysregulation such as obesity, diabetes, hypertension, and metabolic syndrome to the biology of breast cancer among Nigerian women and foster collaborative studies relevant for women of African descent globally

Association of Body Composition with Odds of Breast Cancer by Molecular Subtype: Analysis of the Mechanisms for Established and Novel Risk Factors for Breast Cancer in Nigerian Women (MEND) Study

BACKGROUND: The association between obesity and breast cancer (BC) has been extensively studied among US, European and Asian study populations, with often conflicting evidence. However, despite the increasing prevalence of obesity and associated conditions in Africa, the continent with the highest age-standardized BC mortality rate globally, few studies have evaluated this association, and none has examined in relation to molecular subtypes among African women. The current analysis examines the association between body composition, defined by body mass index (BMI), height, and weight, and BC by molecular subtype among African women. METHODS: We estimated odds ratios (ORs) and 95% confidence intervals (95% CI) for the association between measures of body composition and BC and molecular subtypes among 419 histologically confirmed cases of BC and 286 healthy controls from the Mechanisms for Established and Novel Risk Factors for Breast Cancer in Women of Nigerian Descent (MEND) case-control study. RESULTS: Higher BMI (aOR: 0.79; 95% CI: 0.67, 0.95) and weight (aOR: 0.83; 95% CI: 0.69, 0.98) were associated with reduced odds of BC in adjusted models, while height was associated with non-statistically significant increased odds of BC (aOR: 1.07, 95% CI: 0.90, 1.28). In pre/peri-menopausal, but not post-menopausal women, both higher BMI and weight were significantly associated with reduced odds of BC. Further, higher BMI was associated with reduced odds of Luminal A, Luminal B, and HER2-enriched BC among pre/peri-menopausal women, and reduced odds of triple-negative BC among post-menopausal women. CONCLUSIONS: Higher BMI and weight were associated with reduced odds of BC overall and by molecular subtype among West African women. Larger studies of women of African descent are needed to definitively characterize these associations and inform cancer prevention strategies

Mathematical modeling of drying characteristics of Jew’s mallow (Corchorus olitorius) leaves

Drying behaviour of Jew’s mallow leaves using an oven dryer was studied. The influence of drying temperatures (50, 60 and 70 °C) on moisture content of the leaves at stable air velocity was considered. Five drying models, including, simple exponential, Page, Two-term exponential, Logarithmic, and Wang and Singh were fitted to drying data. Two-term exponential model adequately express the drying behaviour of Jew’s mallow leaves. Effective moisture diffusivity of Jew’s mallow leaves ranged from 8.18 × 10−8 to 1.13 × 10−7 m2/s. Dependence of the computed effective diffusivity on oven temperature was obvious. The energy required for oven drying of Jew’s mallow leaves was found to be 14.84 kJ/mol. The L∗, a∗, b∗, ΔE, a∗/b∗ colour characteristics of the dried leaves range from 31.8 to 32.87, −3.73 to −4.37, 13.6 to 16.47, 69.00 to 69.73, and −0.26 to −0.34 respectively. Oven drying conditions of 50 °C 150 min and 70 °C 90 min resulted to dried leaves with desirable colour characteristics. Keywords: Jew’s mallow, Oven drying, Mathematical modeling, Colour, Effective diffusivity, Activation energ

Physical properties and consumer acceptance of maize-baobab snacks

In this study, an instant maize meal (IMM) was composited with baobab fruit powder (BFP) and commercial starch (CS) which was used as a binding agent. The formulation for the snack was optimised with response surface methodology using design expert software. Thirteen experimental runs were generated by the software and prepared into composite snacks. The snacks were baked using a pilot scale baking oven and microwave oven. The maize-baobab snacks were analysed for colour and texture using different probes (compression force, guillotine, v-shaped and puncture probe). The optimised snacks were evaluated for consumer acceptability and textural properties (instrumental). The results showed an increase in the hardness, fracturability, crunchiness and thickness as the instant maize meal and baobab concentrations increased in the formulation. The colour of the snacks was significantly affected as the concentration of baobab fruit powder and commercial starch increased in the formulation. However, significant correlations existed between sensory attributes and textural parameters in both baking methods except for puncture and aroma of oven-baked snacks