Dietary Effect of Mead Acid on DMBA‑induced Breast Cancer in Female Sprague‑Dawley Rats

In the present study, the dietary effects of mead acid (MA; 5,8,11‑eicosatrienoic acid) on 7,12‑dimethylbenz[a]anthracene (DMBA)‑induced breast cancer in female Sprague‑Dawley rats were examined. The 2.4 and 4.8% MA diets were commenced when the rats were 6 weeks of age. DMBA was administered by a single oral ingestion when the rats were 7 weeks of age, and the rats were maintained on the respective diets until 19 weeks of age. Tumor weight, histopathology, cell kinetics, and the fatty acid composition in breast tissue and serum were examined. In the control (CTR) group, the DMBA‑exposed rats were fed a basal diet (0% MA). The results revealed that there were no significant differences in tumor incidence, cell kinetics and in the N‑6/N‑3 ratio in breast tissue between the groups. Only the N‑6/N‑3 ratio of fatty acid composition in serum was significantly decreased in the 2.4% MA diet group. In previous studies, the 2.4% MA diet was shown to suppress N‑methyl‑N‑nitrosourea‑induced luminal A mammary cancer by decreasing cancer cell proliferation. The findings of the present study differ from those of previous studies with different breast cancer models. To further clarify the effects of MA against breast carcinogenesis, further investigations with different experimental breast cancer models are recommended.