The purpose of this study was to evaluate the effect of genistein in nano, micro, and macro forms on the intensity of the DMBA-induced tumor process in rats and to understand the mechanisms of this action. The effect of genistein supplementation on the content of selected eicosanoids (HETEs, HODE, and HEPE) in the serum of rats was evaluated. The levels and expression of genes encoding various pro-inflammatory cytokines (IL-1, IL-6) and MMP-9 in the blood of rats were also investigated. The biological material for the study was blood obtained from female rats of the Sprague Dawley strain (n = 32). The animals were randomly divided into four groups: animals without supplementation, and animals supplemented at a dose of 0.2 mg/kg b.w. (0.1 mg/mL) with macro, micro (587 ± 83 nm), or nano (92 ± 41 nm) genistein. To induce mammary neoplasia (adenocarcinoma), rats were given 7,12-dimethyl-1,2-benz[a]anthracene (DMBA). The content of selected eicosanoids was determined by liquid chromatography with UV detection. An immunoenzymatic method was used to determine the content of cytokines and MMP-9. The expression of the IL-6, IL-1beta, and MMP-9 genes was determined with quantitative real-time PCR (qRT-PCR) using TaqMan probes. Based on the study, it was shown that supplementation of animals with genistein in macro, micro, and nano forms increased the intensity of the tumor process in rats. It was shown that the content of 12-HEPE, HODE, and 12-HETE in the serum of genistein-supplemented rats was statistically significantly lower with respect to the content of the aforementioned markers in the serum of rats receiving only a standard diet, devoid of supplementation. It was found that animals supplemented with nano-, micro-, and macrogenistein had higher levels of metalloproteinase-9, MMP-9, compared to animals without supplementation. There was a significant increase in MMP-9 gene expression in the blood of macrogenistein-supplemented animals, relative to the other groups of rats. On the basis of the study, it was shown that supplementation of animals with nano-, micro-, and macrogenistein had an effect on the development of the tumor process. Dietary supplementation with genistein significantly decreased the level of selected eicosanoids, which may have significant impacts on cancer development and progression.
Keywords: cancer; genistein; nanoparticles.