Ubiquinol and the papaverine derivative caroverine prevent the expression of tumour- promoting factors in adenoma and carcinoma colon cancer cells induced by dietary fat.

High consumption of dietary fat promotes colon carcinogenesis. While this effect is well known the underlying mechanism is not understood. Fatty acid hydroperoxides (LOOH) arise from unsaturated fatty acids in the presence of oxygen and elevated temperature during food processing.

Suppression of tumour-promoting factors in fat-induced colon carcinogenesis by the antioxidants caroverine and ubiquinone.

Fatty acid hydroperoxides are produced from unsaturated fatty acids in the presence of oxygen at elevated temperatures during food processing. Their effects on gene expression in colorectal tumour cells were studied using linoleic acid hydroperoxide (LOOH) as a model compound. Addition of LOOH to the medium of LT97 adenoma and SW480 carcinoma cells enhanced the production of hydrogen peroxide.

Bile acid induced gene expression in LT97 colonic adenoma cells.

LT97 human colonic adenoma cells reflecting early premalignant genotype and growth characteristics have been posed to tumor promoting bile acids in order to identify marker genes that permit identification of tumor promoters in vitro. Physiologically relevant concentrations of desoxycholate (DOC) and chenodesoxycholate (CDC) upregulated expression of c-fos and COX-2 in a concentration- and time-dependent manner. Transient induction of c-fos was seen with the non-promoting taurodesoxycholate (TDOC) as well as DOC, however extended induction at 3 h was only achieved by DOC and CDC reaching 3-6-fold as compared to the control.

Dietary lipid hydroperoxides induce expression of vascular endothelial growth factor (VEGF) in human colorectal tumor cells.

Fatty acid hydroperoxides arise from unsaturated fatty acids in the presence of oxygen and elevated temperature during processing of food. Here we have studied their effects on gene expression in colorectal tumor cells using linoleic acid hydroperoxide (LOOH) as a model compound. Its addition to the medium of LT97 human adenoma cells and SW480 human carcinoma cells enhanced the production of intracellular hydrogen peroxide.

Induction of lipid peroxidation in biomembranes by dietary oil components.

Prooxidant formation and resulting lipid peroxidation are supposed to be involved in the pathogenesis of various diseases including cancer. Cancer risk is possibly influenced by the composition of diet with high intake of fat and red meat being harmful and high consumption of fruits and vegetables being protective. Since dietary oils may contain potential prooxidants, the aim of the present study was to prove (i) whether oxidative stress in biomembranes may be induced by dietary oils and if, (ii) which impact it has on the viability and proliferation of cultured colon (carcinoma) cells.