Transcriptional activation of HIF-1 by a ROS-ERK axis underlies the resistance to photodynamic therapy.

Photodynamic therapy (PDT), a promising treatment option for cancer, involves the activation of a photosensitizer (PS) by local irradiation with visible light. Excitation of the PS leads to a series of photochemical reactions and consequently the local generation of harmful reactive oxygen species (ROS) causing limited or none systemic defects. However, the development of resistance to this promising therapy has slowed down its translation into the clinical practice.

Developing strategies to predict photodynamic therapy outcome: the role of melanoma microenvironment.

Melanoma is among the most aggressive and treatment-resistant human skin cancer. Photodynamic therapy (PDT), a minimally invasive therapeutic modality, is a promising approach to treating melanoma. It combines a non-toxic photoactivatable drug called photosensitizer with harmless visible light to generate reactive oxygen species which mediate the antitumor effects.