BACKGROUND: Recently, a second-generation photosensory agent for photodynamic therapy (PDT), mono-L: -aspartyl chlorine e6 (NPe6), which degrades rapidly in vivo, has been developed. We evaluated its feasibility and efficacy for treatment in biliary tract carcinoma. METHODS: A transmittance of semiconductor laser light (664 nm), sensitivity of a human biliary tract carcinoma cell line, and disorder to normal tissue including Glissonian constructs and adjacent hepatocytes were investigated. RESULTS: The transmittance of the laser was 85-91% through yellow clear bile and that of the bile including 50 microg/ml NPe6 was 17-48%. The effective concentration of NPe6 which showed LD50 for a cell line was 12.5 microg/ml, and that of LD95 was 25 microg/ml. NPe6 in the supernatant reduced laser transmissiveness, but it had little influence on the antitumor effect in supernatant with or without NPe6. The NOZ cell-tumor volume was reduced significantly 14 days after irradiation in the PDT group (PDT 69.9 +/- 44.6 mm(3) vs control 296.3 +/- 239.9 mm(3) P < 0.05). No severe hepatic disorder including Glisson components was observed by the histological findings. CONCLUSION: NPe6 PDT was effective in carcinomas even in the presence of bile, and causes no serious complication for the liver and Glisson structure. Therefore, NPe6 PDT will be a useful candidate as a new therapy for biliary tract carcinomas.
BACKGROUND: Recently, a second-generation photosensory agent for photodynamic therapy (PDT), mono-L: -aspartyl chlorine e6 (NPe6), which degrades rapidly in vivo, has been developed. We evaluated its feasibility and efficacy for treatment in biliary tract carcinoma. METHODS: A transmittance of semiconductor laser light (664 nm), sensitivity of a humanbiliary tract carcinoma cell line, and disorder to normal tissue including Glissonian constructs and adjacent hepatocytes were investigated. RESULTS: The transmittance of the laser was 85-91% through yellow clear bile and that of the bile including 50 microg/ml NPe6 was 17-48%. The effective concentration of NPe6 which showed LD50 for a cell line was 12.5 microg/ml, and that of LD95 was 25 microg/ml. NPe6 in the supernatant reduced laser transmissiveness, but it had little influence on the antitumor effect in supernatant with or without NPe6. The NOZ cell-tumor volume was reduced significantly 14 days after irradiation in the PDT group (PDT 69.9 +/- 44.6 mm(3) vs control 296.3 +/- 239.9 mm(3) P < 0.05). No severe hepatic disorder including Glisson components was observed by the histological findings. CONCLUSION: NPe6 PDT was effective in carcinomas even in the presence of bile, and causes no serious complication for the liver and Glisson structure. Therefore, NPe6 PDT will be a useful candidate as a new therapy for biliary tract carcinomas.
Authors: Sabrina Gloria Giulia Testoni; Andrew James Healey; Christoph F Dietrich; Paolo Giorgio Arcidiacono Journal: Endosc Ultrasound Date: 2020 Mar-Apr Impact factor: 5.628