Induction of Apoptosis and Antiproliferative Activity of MCF-7 Human Breast Cancer Cells with Sonicated Aqueous Peel Extract of Punica granatum L. (Nimali sp.).

BACKGROUND: The antioxidant and antiproliferative activities of various parts of the Punica granatum L. fruit (Nimali variety) on MCF-7 human breast cancer cells have been investigated.  The analysis of the effect on gene regulation and apoptosis induction compared to different extraction methods, was carried out highlighting the fruit's potential anticancer properties attributed to polyphenol-rich composition. METHODS: This study analyzed alterations in radical scavenging capacity (RSC), phenol (TPC), and flavonoid contents (FC) of pomegranate fruit parts, and antiproliferative activity towards MCF-7 cancer cells using different extraction methods. Most effective peel extract/s were analyzed for total protein content, nitric oxide production, LDH, and Caspase 3 and 8 activities. RT-qPCR was performed with intact RNA to examine the apoptotic pathway and gene expression, and western blot analysis confirmed the presence of tumor suppressor protein/s. RESULTS: The sonicated peel extract (SPL) exhibited the highest RSC, TPC, and FC. Fermented juice displayed higher RSC, TPC, and FC compared to fresh juice. Sonicated peel extract showed an IC50 value of 130±4.5 μg mL-1 against MCF-7 cells, while VERO (healthy) cells had values >1,000 μg mL-1. Sonication was identified as the most effective extraction method for the antiproliferative activity of pomegranate fruit. The study revealed that SPL induced apoptosis via the p21, p53-dependent, caspase 8 pathways, and caspase 3-independent mechanisms in MCF-7 cells. CONCLUSION: Findings emphasize the potential therapeutic effects of SPL in the antiproliferative effect of  MCF-7 cells by modulating caspase 8, p53, and p21-dependent pathways, without activating caspase 3.