Mediation Effect of Physical Activity on Obesity in Black Women.

BACKGROUND AND OBJECTIVE: Sociodemographic and lifestyle factors, physical activity, diet, and nutrients are important in the understanding of obesity. The possibly direct or indirect nature of the associations among these factors and the eventual link to obesity is not well understood. In this study, we assess the indirect association between socio-demographic factors and obesity. DESIGN: A case-control study involving African American women conducted at Howard University Cancer Center. PARTICIPANTS AND METHODS: One hundred ninety eight participants gave information on anthropometric measurements, intake of dietary supplements and nutrients, socio-demographic factors (age, marital status, income and education) and physical activity. Path analysis was utilized to assess associations between socio-demographic factors and obesity through physical activity, dietary supplements and nutrients, smoking or alcohol consumption. MAIN RESULTS: The mean age of the participants was (55 ± 12 years), with 50% being obese (BMI ≥ 30 kg/m2). Obesity level decreased by approximately 7% for every one level increase in education via its prior effect on vigorous physical activity. Age had a significant positive indirect effect on obesity through vigorous physical activity - with obesity levels increasing by approximately 6% for every one year increase in age via its prior effect on vigorous physical activity. CONCLUSIONS: Vigorous physical activity mediates the association between education and age on obesity.

Frequent loss of the BLID gene in early-onset breast cancer.

The BH3-like motif-containing inducer of cell death (BLID) is an intronless gene localized on 11q24.1. Loss of that region has frequently been reported in early-onset breast cancer and is significantly associated with poor prognosis and reduced survival. Downregulation of BLID is associated with younger age, triple-negative phenotype, and reduced disease-free and overall survival of breast cancer patients. In this study, we investigated allelic loss of BLID in breast tumor specimens from 78 women with invasive breast cancer using 2 dinucleotide polymorphic markers closely linked to the BLID gene (no intragenic marker for BLID is available). Seventy-three cases were informative. Overall, loss of heterozygosity (LOH) at the BLID locus was detected in 32% of the informative cases (23/73). However, in patients 40 years old and younger, LOH was detected in 50% of the cases (9/18). Patients aged 40 years and younger were significantly more likely to experience LOH than those aged 41-55 years (p = 0.04). Specifically, the odds of BLID loss for patients aged 40 years and younger were 3.7 times the odds of loss for patients aged 41-55 years (95% CI, 1.1-13). Our findings suggest a tumor suppressor role of the BLID gene in early-onset breast cancer.