Predicted Vitamin D Status and Colorectal Cancer Incidence in the Black Women's Health Study

Exploration and Identification of Vitamin D and Related Genes as Potential Biomarkers for Colorectal Tumors

Objective

To explore the relationship and underlying mechanisms between vitamin D and CRC, offering valuable insights into the diagnosis and treatment of CRC.

Materials and Methods

Serum levels of 1,25(OH)2D3 were measured using a double-antibody sandwich assay. Bioinformatics analysis identified vitamin D-related CRC genes, which were validated using HCT116 and HT29 cell lines. Changes in hub gene expression were analyzed via RT-qPCR.

Results

Serum levels of 1,25(OH)2D3 were 42.99±6.02µg/mL in the normal group, 37.06±9.56µg/mL in the CRA group, and 19.00±5.96µg/mL in the CRC group (p<0.05). No significant differences were observed in VDR SNPs among the groups. Significant expression differences were detected in vitamin D-related colon cancer genes across the groups. LASSO regression analysis identified 5 key genes. The diagnostic model based on these genes demonstrated high diagnostic efficiency and performed well in the TCGA-COAD dataset. RT-qPCR results showed that SOSTDC1, PRKAA2, and CEACAM1 expressions decreased in the CRC and CRA groups, while MMP1 and CCND1 expressions increased. In vitro experiments indicated that calcitriol inhibits the proliferation and migration of HCT116 and HT29 cell lines and significantly alters the expression of hub genes.

Conclusion

Serum vitamin D levels are significantly lower in CRC patients. Vitamin D has been shown to inhibit the proliferation and migration of colon cancer cells and reduce the expression of oncogenes. Therefore, vitamin D holds substantial potential for the diagnosis and treatment of CRC.

Associations between diet and nutritional supplements and colorectal cancer: A systematic review

Background and Aim

Colorectal cancer (CRC) is one of the most prevalent cancers around the world. The link between nutrients and the likelihood of developing CRC remains uncertain. The primary objective of the present study was to investigate the potential connection between dietary intake/dietary supplements and the occurrence of CRC through a literature review.

Methods

A comprehensive online search was conducted in PubMed, Scopus, Web of Science, and the Cochrane Library from January 1990 to March 2023 using appropriate keywords. A systematic search was conducted for clinical trials and cohort studies in order to determine the relationship between dietary components/supplements and CRC.

Results

The intake of long-chain n-3 polyunsaturated fatty acids (n-3 LCPUFAs), consisting of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), has the potential to decrease the likelihood of developing CRC (eight studies found positive effects and four studies found no association). Some other dietary components such as probiotics, prebiotics, and synbiotics may contribute to suppressing CRC development (three studies found positive effects, whereas three studies did not find any association). There is inconclusive evidence that supplementation with certain micronutrients including vitamin D (one trial found positive effects and another trial reported no association), folate, zinc, and selenium may reduce the risk of CRC.

Conclusion

Some dietary supplements such as n-3 LCPUFAs and probiotics have the potential to reduce the risk of developing CRC. Further studies are necessary to validate these results and understand the underlying mechanisms.

The Non-Invasive Prediction of Colorectal Neoplasia (NIPCON) Study 1995-2022: A Comparison of Guaiac-Based Fecal Occult Blood Test (FOBT) and an Anti-Adenoma Antibody, Adnab-9

Given the need to improve the sensitivity of non-invasive methods to detect colorectal neoplasia, particularly adenomas, we compared a fecal test using a monoclonal antibody (Mab) raised against constituents of colonic adenomas designated Adnab-9 (Adenoma Antibody 9), recognizing an N-linked 87 kDa glycoprotein, to gFOBT, which is shown to reduce CRC mortality. p87 immunohistochemistry testing is significantly more sensitive (OR 3.64[CI 2.37-5.58]) than gFOBT (guaiac-based fecal occult blood test) for adenomas (<3 in number), advanced adenomas (OR 4.21[CI 2.47-7.15]), or a combination of the two (OR 3.35[CI 2.47-4.53]). p87 immunohistochemistry shows regional Paneth cell (PC) expression mainly in the right-sided colon and is significantly reduced in the ceca of African Americans (p < 0.0001). In a subset of patients, we obtained other body fluids such as urine, colonic effluent, and saliva. Urine tests (organ-specific neoantigen) showed a significant difference for advanced adenomas (p < 0.047). We conclude that fecal p87 testing is more sensitive than gFOBT and Adnab-9 and could be used to better direct the colonoscopy screening effort.

Vitamin D and risk of hypertension among Black women

Evidence of an association between plasma 25-hydroxyvitamin D [25(OH)D] levels and risk of hypertension, predominantly from studies of White individuals, suggests an inverse relationship. Limited data are available on Black individuals, who are more likely to have vitamin D deficiency. In the Black Women's Health Study (BWHS), a prospective study of 59 000 self-identified Black women from across the US, we assessed levels of a validated predicted vitamin D score in relation to incident hypertension. We followed 42 239 participants who were free of cardiovascular disease and cancer from 1995 to 2019, during which time 19 505 incident cases of hypertension were identified. Cox proportional hazards model were used to calculate multivariable-adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for the association of predicted vitamin D with the risk of incident hypertension. In age-adjusted analyses, there was a strong inverse dose-response association between predicted vitamin D score and hypertension risk, with an HR of .66 (95% CI: .63-.68, p trend < .0001) for the highest quartile of predicted vitamin D relative to the lowest. After control for potential confounders including body mass index, physical activity, and cigarette smoking, the HR was attenuated to .91 (95% CI: .87-.95, p trend = .002). In this prospective cohort study of Black women, predicted vitamin D score was weakly inversely associated with the incidence of hypertension. This observed association may reflect an inability to fully control for confounding factors.