Roles Of Calcium Signaling Pathway And Mitogen Activated Protein Kinases Signaling Pathway Of Colon Carcinoma Cells In Response To δ-Aminolevulinic Acids-Based Photodynamic Therapy

Photodynamic therapy(PDT) of cancer is based on the tumor-specific accumulation of a photosensitizer, followed by irradiation with visible light, reactive oxygen species(ROS) is generated, which induces cell death and apoptosis. So far, PDT of some malignant tumors has been ratified by Canada, American, French, Dutch Germany, Japan and so on. But common photosensitizer needs patients to avoid light exposure for more than 20 days and it have many side effects, whose drawbacks may limit applicability of PDT in treatment of tumors.δ-aminolevulinic acid(ALA)-PDT based on endogenously formed protoporphyrin IX (PPIX) following incubation of cells withδ-aminolaevulinic acid. By this procedure the feedback control of haem biosynthesis is bypassed and high amounts of ultimate heme precursor, the photosensitizing compound PPIX, are accumulated in cancerous cells. Subsequent irradiation of ALA-treated cells with visible light leads to destruction of cancerous cell. ALA-PDT is a...