Figure 7.
Methylene‐blue‐mediated photodynamic therapy (MB‐PDT) mediated induction of apoptosis by mitochondria‐dependent pathway. MB seems to selectively bind to mitochondria, where it produces reactive oxygen species (ROS) after excitation in combination with light. Then ROS act on mitochondria to induce an imbalance between ROS production and antioxidant capacity, which can be proved by proteomics study of alterations of proteins, such as peroxiredoxin‐1 and 6, GST‐piA, complex I‐49 kDa and COQ9. Consequently, MB‐PDT mediated oxidative stress causes impairment of mitochondrial integrity and function, resulting in release of cytochrome c and loss of mitochondrial membrane potential (Δψm ), which ultimately leads to apoptotic cell death and tumor destruction.