Cationic Ester Porphyrins Cause High Levels of Phototoxicity in Tumor Cells and Induction of Apoptosis in HeLa Cells

A series of cationic ester porphyrins are much more cytotoxic to tumor cells than photofrin, meso-tetrakis(1-methylpyridinium-4-yl)porphyrin (TMPyP4), and cisplatin. The lowest IC(50) value for SGC7901 is ca. 6 nM in vitro with irradiation. These porphyrins also exhibited the most potent photo-induced cytotoxicity without photobleaching. HeLa Cell apoptosis induced by cationic ester porphyrins after illumination was examined by flow cytometric analysis, staining assays with propidium iodide and annexin V FITC-PI, and further confirmed by observing morphological changes in the cells. The result of this study indicates that these cationic ester porphyrins may be applied in photodynamic therapy (PDT) in the future.