Search

The use of photodynamic therapy (PDT) and development of novel photosensitizers (PSs) for cancer treatment have received more and more attention nowadays. In the present work, five benzo[a]phenoxazinium derivatives have been prepared and evaluated for their in vitro anticancer photodynamic activity for the first time. They are red light absorbers and show low fluorescence quantum yield. Of these compounds, PS4 exhibited a higher quantum yield for reactive oxygen species (ROS) generation. The assays with cells in vitro showed that PS1 and PS4 were not significantly toxic in the dark, but was robustly toxic against the murine breast adenocarcinoma cells 4T1 and normal murine fibroblast cells NIH-3T3 upon photoactivation. More interestingly, PS5 was particularly selective towards 4T1 cancer cells and nearly non-phototoxic to non-cancerous NIH-3T3 cells. The results described in this report suggest that these new benzo[a]phenoxazinium derivatives are potential candidates as PSs for anticancer PDT. Further investigation of benzo[a]phenoxaziniums for anticancer PDT is warranted. [ABSTRACT FROM AUTHOR]

The use of photodynamic therapy (PDT) and development of novel photosensitizers (PSs) for cancer treatment have received more and more attention nowadays. In the present work, five benzo[ a ]phenoxazinium derivatives have been prepared and evaluated for their in vitro anticancer photodynamic activity for the first time. They are red light absorbers and show low fluorescence quantum yield. Of these compounds, PS4 exhibited a higher quantum yield for reactive oxygen species (ROS) generation. The assays with cells in vitro showed that PS1 and PS4 were not significantly toxic in the dark, but was robustly toxic against the murine breast adenocarcinoma cells 4T1 and normal murine fibroblast cells NIH-3T3 upon photoactivation. More interestingly, PS5 was particularly selective towards 4T1 cancer cells and nearly non-phototoxic to non-cancerous NIH-3T3 cells. The results described in this report suggest that these new benzo[ a ]phenoxazinium derivatives are potential candidates as PSs for anticancer PDT. Further investigation of benzo[ a ]phenoxaziniums for anticancer PDT is warranted.

Nanotechnology has provided powerful tools to improve the chemotherapy of cancer. Different nanostructures have been developed which deliver the anticancer drugs more selectively to tumor than to healthy tissues. The result has generally been the increase in efficacy and safety of classical anticancer drugs. In recent years, several studies have focused not only on the delivery of anticancer drugs to tumors, but also on delivering the drugs to specific organelles of cancer cells. Endoplasmic reticulum, Golgi apparatus, lysosomes, mitochondria, and nucleus have been the targets of different nanostructured drug delivery systems developed with the goal of circumventing drugresistance, increasing drug efficacy, and so on. So far, the results described in the literature show that this strategy may be used to improve chemotherapy outcomes. In this review a discussion is presented on the strategies described in the literature to deliver anticancer drugs to specific organelles of cancer cells by using nanostructures.