Caspase-1 Regulates the Apoptosis and Pyroptosis Induced by Phthalocyanine Zinc-Mediated Photodynamic Therapy in Breast Cancer MCF-7 Cells

Photodynamic therapy (PDT) is an innovative and perspective antineoplastic therapy. Tetra-a-(4-carboxyphenoxy) phthalocyanine zinc (TaPcZn)-mediated PDT (TaPcZn-PDT) has shown antitumor activity in some tumor cells, but the manner in which caspase-1 is involved in the regulation of apoptosis and pyroptosis in the TaPcZn-PDT-treated breast cancer MCF-7 cells is unclear. Therefore, effects of TaPcZn-PDT on cytotoxicity, cell viability, apoptosis, pyroptosis, cellular reactive oxygen species (ROS), mitochondrial membrane potential (??m), caspase-1, caspase-3, and nuclear transcription factor-?B (NF?B) in MCF-7 cells was firstly examined in the present study. The findings demonstrated that TaPcZn-PDT resulted in the increase in cytotoxicity and the percentage of apoptotic and pyroptotic cells, the reduction in cell viability and ??m, the production of ROS and the activation of caspase-1, caspase-3 and NF?B in MCF-7 cells. Furthermore, the results also revealed that siRNA-targeting caspase-1 (siRNA-caspase-1) attenuated the effect of TaPcZn-PDT on apoptosis, pyroptosis and the activation of caspase-1, caspase-3 and NF?B in MCF-7 cells. Taken together, we conclude that caspase-1 regulates the apoptosis and pyroptosis induced by TaPcZn-PDT in MCF-7 cells.