9-hydroxypheophorbide a

9-hydroxypheophorbide a is a chlorophyll-derived second-generation photosensitizer investigated for use in photodynamic therapy (PDT). It is a derivative of pheophorbide a, characterized by the presence of a hydroxyl group at the C-9 position. When activated by specific wavelengths of light, typically around 670 nm, the molecule transfers energy to molecular oxygen to generate singlet oxygen and other reactive oxygen species (ROS). These ROS induce localized oxidative stress, leading to cell death through the activation of apoptotic pathways, specifically involving the cleavage of caspase-3, caspase-9, and poly(ADP-ribose) polymerase (PARP). Research has demonstrated that 9-hydroxypheophorbide a can work synergistically with chemotherapeutic agents like carboplatin to enhance cytotoxicity in malignant cells, such as head and neck cancer cell lines.

Other names

9-hydroxypheophorbide alpha9-hydroxy-pheophorbide a