Vitamin and mineral supplements for cancer prevention: issues and evidence

An Update on Tamoxifen and the Chemo-Preventive Potential of Vitamin E in Breast Cancer Management

Breast cancer (BC) is the most common female cancer in terms of incidence and mortality worldwide. Tamoxifen (Nolvadex) is a widely prescribed, oral anti-estrogen drug for the hormonal treatment of estrogen-receptor-positive BC, which represents 70% of all BC subtypes. This review assesses the current knowledge on the molecular pharmacology of tamoxifen in terms of its anticancer and chemo-preventive actions. Due to the importance of vitamin E compounds, which are widely taken as a supplementary dietary component, the review focuses only on the potential importance of vitamin E in BC chemo-prevention. The chemo-preventive and onco-protective effects of tamoxifen combined with the potential effects of vitamin E can alter the anticancer actions of tamoxifen. Therefore, methods involving an individually designed, nutritional intervention for patients with BC warrant further consideration. These data are of great importance for tamoxifen chemo-prevention strategies in future epidemiological studies.

Aberrantly methylated-differentially expressed genes and related pathways in cholangiocarcinoma

This study aimed to explore aberrantly methylated-differentially expressed genes and related pathways in cholangiocarcinoma (CCA).The mRNA expression data (GSE26566) and methylation profiling data (GSE44965) were collected from the Gene Expression Omnibus (GEO) Datasets. Differentially expressed genes and differentially methylated genes were identified using GEO2R. Gene ontology analysis and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses were performed using clusterprofiler in R. MCODE clustering tool was used to screen modules of the protein-protein interaction network in Cytoscape. Related pathways of hub gene by using gene set enrichment analysis.Eighty-one hypermethylated, lowly expressed genes (Hyper-LGs) and 76 hypomethylated, highly expressed genes (Hypo-HGs) were identified in this study. Hyper-LGs were enriched in ion channel binding and transcription factor activity, which was associated with Mineral absorption and Cell adhesion molecules. Hypo-HGs were enriched in cysteine-type endopeptidase activity, which was associated with Sphingolipid signaling pathway and T cell receptor signaling pathway. Based on protein-protein interaction networks, MYC and VWF were identified as hub genes for Hyper-LGs, and no hub genes for Hypo-HGs.This study found methylated-differentially expressed genes and signaling pathways that are connected with the CCA by using a series of bioinformatics databases and tools. MYC and VWF act as hub genes of CCA, which can be used as biomarkers based on aberrant methylation for the accurate diagnosis and treatment of CCA.

The use of daily aspirin, nutritional supplements and alternative medications among Amish and non-Amish living in Ohio Appalachia

The purpose of this study was to assess daily aspirin and supplement use among Amish and non-Amish adults living in Ohio Appalachia to understand their potential contribution to lower cancer incidence rates among the Amish. A cross-sectional study was conducted with random samples of 134 Amish adults and 154 non-Amish adults. Face-to-face interviews about cancer-related behaviors included questions regarding aspirin and supplement use. Amish compared to non-Amish adults reported 1) taking significantly (P < 0.05) more supplements [mean number of daily products by Amish males (3.5 ± 3.7) and females (5.2 ± 4.3) vs. non-Amish males (1.4 ± 1.3) and females (3.0 ± 3.2)]; 2) taking significantly (P < 0.05) more vitamins, minerals, fiber supplements (females only), and enzymes (females only); 3) taking significantly (P < 0.01) more herbal supplements (approximately 55% and 71% of Amish males and females vs. 17% and 23% of non-Amish males and females, respectively); and 4) taking significantly (P < 0.05) less aspirin on a regular basis. Aspirin and supplement use among Amish and non-Amish adults show significant differences characteristic of their social and cultural norms. Future studies that clarify the impact of aspirin and supplement use among the Amish and their impacts upon the risk of certain cancers and other disease processes are warranted.

Lessons learned from randomized clinical trials of micronutrient supplementation for cancer prevention

This review discusses the results of randomized clinical trials of supplemental micronutrients for cancer prevention completed over the past 20 years, including trials of beta-carotene and retinol, vitamins C and E, selenium, folic acid, and vitamin D. Some trials observed significant reductions in risk, whereas others observed significant increases in risk of the primary cancer endpoint. In considering these trials, it appears that supplementation targeted to populations with low status of the nutrient of interest may prevent cancer, whereas supplementation in populations with higher status or to achieve pharmacological exposures may promote cancer. Observational epidemiologic evidence coupled with these trial results supports the concept of a U-shaped curve for micronutrients in relation to cancer prevention. Based on these data, nutrient supplements are not currently recommended for cancer prevention in the general population. The hypothesis that groups with low nutrient status may benefit from supplementation has yet to be formally tested.