In this study, copper chlorophyllin was used as a photosensitizer for photodynamic therapy (PDT) in Ehrlich tumour mouse model. Six groups of animals comprising 5 animals per group were subcutaneously transplanted with 1x10⁶ Ehrlich tumour cells. A single dose of 200 μg/gm body weight chlorophylin derivative was administered by intravenous (IV) or intratumoral (IT) routes. Mice were exposed to monochromatic red laser of 630 nm for 1 h, and tumour regression was followed up for three consecutive months post treatment. Several Biochemical, histological and molecular tests were performed in order to evaluate the efficacy and safety of the applied treatment. An interest has been also directed towards investigating the molecular mechanisms underlying chlorophyllin derivative mediated PDT. PDT-treated animals via either the IV or IT routes showed significant decrease in tumour size 72 h post-treatment. Tumours at the IV-PDT group disappeared totally within a week with no recurrence over three months follow up. In the IT-PDT, the decrease in tumour size at the first week was interrupted by a slight increase; however never reached the original size. Histological examination of tumour tissues of the IV-PDT group at 24 h post treatment demonstrated restoring the normal muscle tissue architecture, and the biochemical assays indicated normal liver functions. The immunohistochemical analysis of caspase-3, and the quantitative PCR results of caspases-8 and 9 proved the presence of extrinsic apoptotic pathway after cholorphyllin derivative-mediated PDT. In conclusion IV-PDT strategy proved better cure rate than the IT-PDT, with no recurrence over three months of follow up.

Date Published: 2 March 2015
PDF: 9 pages
Proc. SPIE 9308, Optical Methods for Tumor Treatment and Detection: Mechanisms and Techniques in Photodynamic Therapy XXIV, 930813 (2 March 2015); doi: 10.1117/12.2080247

Published in SPIE Proceedings Vol. 9308:
Optical Methods for Tumor Treatment and Detection: Mechanisms and Techniques in Photodynamic Therapy XXIV
David H. Kessel; Tayyaba Hasan, Editor(s)