Protective effect of purple sweet potatoes (Ipomoea batatas L.) against rat breast cancer

Background and Aim: Breast cancer is one of the most prevalent and lethal malignancies affecting women worldwide. Given the limitations of conventional treatments, there is an increasing interest in exploring naturally derived compounds with chemoprotective properties. Purple sweet potatoes (Ipomoea batatas L.) are rich in anthocyanins and have been reported to possess antioxidant, anti-inflammatory, and anticancer activities. This study aimed to evaluate the chemopreventive potential of ethanolic extracts from purple sweet potato peels in a rat model of 7,12-dimethylbenz(a)anthracene (DMBA)-induced breast cancer. Materials and Methods: Fifty female Rattus norvegicus (170–200 g) were randomized into five groups. Breast tumors were induced through a single subcutaneous dose of DMBA (20 mg/rat). Three experimental groups received daily oral administration of the extract at 200, 400, and 600 mg/kg body weight, respectively, for 4 months. One control group received only DMBA, while another received the highest dose of the extract without DMBA. Antioxidant activity was assessed using 2,2-diphenyl-1-picrylhydrazyl-hydrate (DPPH) and 2,2’-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) assays. Anthocyanin content was quantified using spectrophotometry. Tumor latency, tumor volume, and histopathological alterations were evaluated to determine the extract’s chemopreventive effects. Results: The extract exhibited significant antioxidant activity comparable to quercetin at 1500 ppm (DPPH assay) and a high anthocyanin content (138.92 ± 0.58 mg/100 g dry extract). Tumor latency was significantly prolonged in the 600 mg/kg group (101 days) compared to the DMBA control (88 days). In addition, this group showed a marked reduction in tumor volume (2.26 cm3 vs. 15.21 cm3; p < 0.05). Histological examination revealed improved ductal epithelial integrity and reduced necrosis in extract-treated groups, particularly at the highest dose. Conclusion: The ethanolic extract of purple sweet potato peels demonstrated a dose-dependent chemopreventive effect against DMBA-induced breast cancer in rats. The extract’s high anthocyanin content likely contributed to its antioxidant and antitumor activities. These findings suggest potential applications in dietary chemoprevention, warranting further investigation into its molecular mechanisms and clinical translation.