Targeted Photodynamic Therapy of Human Head and Neck Squamous Cell Carcinoma with Anti ‐epidermal Growth Factor Receptor Antibody Cetuximab and Photosensitizer IR700DX in the Mouse Skin‐fold Window Chamber Model

In this study the EGFR over‐expressing human head/neck OSC‐19‐luc2‐cGFP tumour with transfected GFP gen e was used in a skin‐fold window‐chamber model in BALB/c nude mice. The uptake and localization of the conjugate in the tumour and its surrounding normal tissues were studied by an intravital confocal laser scanning microscopy with image analyses. The tumour was also irradiated with 690 nm las er light 24 hours after conjugate administration. The vascular and tumour responses were examined by morphological evaluation and immunohistochemistry (IHC). The amount of conjugate in the tumour peaked at 24‐48 hours after injection. Image analyses of colocalization correlation parameters demonst rated a high fraction of the conjugate IR700DX colocalised in the GFP‐expressing tumour cells. PDT‐treated tumours showed extensive necrotic/apoptotic destruction with little vascular damage; while IHC showed no HIF‐1α expression and decreased EGFR and Ki67 expression with activated caspase‐ 3 overexpression, indicating a direct killing of tumour cells through both necrotic and apoptotic cell death.
Source: Photochemistry and Photobiology - Category: Science Authors: Tags: SPECIAL ISSUE RESEARCH ARTICLE Source Type: research