Enhanced anticancer potential of Punica granatum fruit extract in combination with Pheophorbide-a mediated photodynamic therapy on MCF-7 breast cancer cells

Combination therapy refers to the simultaneous administration of several therapeutic medications and treatment procedures with diverse biochemical and molecular targets and mechanisms of action. This is now used to treat a range of cancers. Furthermore, the search for less toxic natural alternatives has gained importance, which has led researchers’ interest in phytotherapy-based combination therapies. Punica granatum leaf, fruit, seed, and peel extracts, like many other medicinal plants, contains a high concentration of phytochemicals like tannins, anthocyanidins, phenolics, and have shown to be effective in cancer treatment. In this study, the anticancer potentials of P. granatum extract were evaluated in combination with a chlorophyll derivative photosensitizer, pheophorbide-a mediated photodynamic therapy (PDT) against MCF-7, a human breast cancer cell line. The effects of single and combination therapy on the viability and morphology, were examined using, adenosine triphosphate (ATP) assays, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) reduction, and bright field and LIVE/DEAD assay respectively. The apoptotic cell death were determined by FITC-Annexin V/ Propidium Iodide assay, caspase, cytochrome-c, and Bax/Bcl-2 activity. This study demonstrated that combination treatment significantly inhibited the MCF-7 cell growth with an IC₅₀ value of 129 µg/mL compared to extract treatment alone at ~ 289 µg/mL at 24 h. Initiation of apoptosis indicated that it was mediated by the extrinsic and intrinsic pathways according to the enhanced levels of both caspase-8 and caspase-9 enzymes. Our findings suggest that a combination of phytocompound-based therapeutic modalities with different mechanisms of action has the potential to significantly improve cancer treatment efficacy when compared to single-agent therapy.