Lowering photosensitizer doses and increasing fluences induce apoptosis in tumor bearing mice

Abstract

Abstract:The objective of this study was to determine an optimal dose of photodynamic therapy (PDT) for inducing apoptotic tumor cells in vivo. In this context, mice bearing human tongue-squamous epithelium carcinomas were treated with various photosensitizer concentrations and fluences. Tumor apoptosis was imaged after 2 days via a self-designed DY-734-annexin V probe using near-infrared fluorescence (NIRF) optical imaging. Apoptosis was verified ex vivo via TUNEL staining. Apoptotic tumor cells were detected in vivo at a dose of 40 µg photosensitizer and a fluency of 100 J/cm 2 . This is the lowest photosensitizer dose reported so far.

SHG-enhanced NIR-excitedin vitrophotodynamic therapy using composite nanoparticles of barium titanate and rose Bengal

“…The triplet PSs are likely to interact with oxygen or oxygen-containing groups, which would generate toxic reactive oxygen species (ROS) and cause cell apoptosis or necrosis. [9][10][11][12] Since the above process (known as photodynamic effect) can only occur when suitable light and PSs are both present, the treatment region can be carefully selected and side effects would be small.…”