Photodynamic effects of sulfonated aluminum chlorophthalocyanine in human urinary bladder carcinoma cells in vitro.

Objectives: Topically applied photosensitizers are particularly suited for use in the photodynamic therapy of urinary bladder tumors. The objective of the present study was to investigate the photodynamic effects of sulfonated aluminum chlorophthalocyanine on human bladder carcinoma cells.
Methods: The photodynamic efficiency and the morphologic changes induced by sulfonated aluminum chlorophthalocyanine on human bladder carcinoma cells and normal bladder wall cells were investigated in vitro using light microscopy and in order to determine the subcellular target organelles using electron microscopy.
Results: Examination of tumor cells with light microscopy after previous photodynamic therapy initially showed distension of the cells and, depending on the duration, a significant blistering of the cell membrane, leading, in some cases, to rupture of the cells. Electron microscopy revealed destruction of the mitochondria. No changes in other cell organelles or structures were observed.
Conclusions: Sulfonated aluminum chlorophthalocyanine exhibits good photodynamic activity in bladder tumor cells with relative tumor selectivity. The primary cellular target of photodynamic therapy seems to be the mitochondria.