African American men have higher incidence rates of aggressive prostate cancer, where high levels of calcium and serum vitamin D deficient levels play a role in the racial differences in incidence. In this study, we examined associations of serum vitamin D with aggressive prostate cancer to improve our understanding of higher susceptibility of aggressive disease in this racial cohort. From Howard University Hospital, 155 African American men with clinically-identified prostate cancer were identified; 46 aggressive cases, and 58 non-aggressive cases. Serum vitamin D was assessed from fasting blood samples, and total calcium intake was assessed using the Block Food Frequency Questionnaire. Vitamin D receptor polymorphisms from three different loci were genotyped; rs731236, rs1544410, and rs11568820. Multivariate logistic regression models were used to determine odds ratios (OR) and 95% confidence intervals (CI) comparing aggressive to non-aggressive prostate cancer. Vitamin D deficiency (<20 ng/mL) significantly increased risk of aggressive disease (OR: 3.1, 95% CI: 1.03–9.57, p-value = 0.04). Stratification by total calcium showed high calcium levels (≥800 mg/day) modified this association (OR: 7.3, 95% CI: 2.15–47.68, p-interaction = 0.03). Genetic variant rs11568820 appeared to increase the magnitude of association between deficient serum vitamin D and aggressive prostate cancer (OR: 3.64, 95% CI: 1.12–11.75, p-value = 0.05). These findings suggest that high incidence of aggressive prostate cancer risk in African American men may be due in-part to deficient levels of serum vitamin D. Other factors, including genetics, should be considered for future studies.

Trends in biliary tract cancer incidence rates have increased in Shanghai, China. These trends have coincided with economic and developmental growth, as well as a shift in dietary patterns to a more Westernized diet. To examine the effect of dietary changes on incident disease, we evaluated associations between diet and biliary tract cancers amongst men and women from a population-based case-control study in Shanghai, China. Biliary tract cancer cases were recruited from 42 collaborating hospitals in urban Shanghai, and population-based controls were randomly selected from the Shanghai Household Registry. Food frequency questionnaire data were available for 225 gallbladder, 190 extrahepatic bile duct, and 68 ampulla of Vater cancer cases. A total of 39 food groups were created and examined for associations with biliary tract cancer. Interestingly, only four food groups demonstrated a suggested association with gallbladder, extrahepatic bile duct, or ampulla of Vater cancers. The allium food group, consisting of onions, garlic, and shallots showed an inverse association with gallbladder cancer (OR: 0.81, 95% CI: 0.68–0.97). Similar trends were seen in the food group containing seaweed and kelp (OR: 0.79, 95% CI: 0.67–0.96). In contrast, both preserved vegetables and salted meats food groups showed positive associations with gallbladder cancer (OR:1.27, 95% CI: 1.06–1.52; OR: 1.18, 95% CI: 1.02–1.37, respectively). Each of these four food groups showed similar trends for extrahepatic bile duct and ampulla of Vater cancers. The results of our analysis suggest intake of foods with greater anti-inflammatory properties may play a role in decreasing the risk of biliary tract cancers. Future studies should be done to better understand effects of cultural changes on diet, and to further examine the impact diet and inflammation have on biliary tract cancer incidence.

Vitamin D has been discussed in the context of cardiovascular disease, cancer, bone health and other outcomes. Epidemiological studies have reported on the importance of vitamin D in cancer prevention and treatment. The discovery of vitamin D-associated metabolites through agnostic metabolomics analyses offers a new approach for elucidating disease aetiology and health-related pathway identification. Baseline serum 25-hydroxy-vitamin D [25(OH)D] and 940 serum metabolites were measured in 392 men from eight nested cancer case-control studies in the Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study of Finnish male smokers (aged 50-69 years). The metabolomic profiling was conducted using mass spectrometry. We used linear regression to estimate the standardized beta-coefficient as the effect metric for the associations between metabolites and 25(OH)D levels. A majority of the metabolites associated with 25(OH)D were of lipid origin, including 3-carboxy-4-methyl-5-propyl-2-furanpropanoic acid (CMPF) [beta-estimate 0.38 per 1 standard deviation (SD) increment], stearoyl-arachidonoyl-glycerophosphoethanolamine (GPPE) (-0.38 per SD) and two essential fatty acids: eicosapentaenoate (EPA; 0.17 per SD) and docosahexaenoate (DHA; 0.13 per SD). Each of these lipid metabolites was associated with 25(OH)D at the principal components corrected P-value of 3.09 × 10^-4 CONCLUSIONS: The large number of metabolites, particularly lipid compounds, found to be associated with serum 25(OH)D provide new biological clues relevant to the role of vitamin D status and human health outcomes. The present findings should be re-examined in other metabolomics studies of diverse populations.