THIRD PARTY CLINICAL STUDIES / NEXT GENERATION PDT

STUDY BY:
LI Wen-min - CAI Xiao-jun - LI Yan-bing - CHEN Wen-hui - LI Li-bo1 - LUO Rong-cheng
Department of Oncology Nanfang Hospital
Southern Medical University Guangzhou 510515 China
Shanghai Fudan - Zhangjiang R&D Center for Photodynamic Therapy Drug


基金项目: 广东省科技计划项目( 2010B031600246)
作者单位: 1. 南方医科大学南方医院肿瘤科( 广州市,5
10515) 2. 上海复旦张江光动力药物研发中心
作者简介: 李文敏( 1986 ~ ) ,女,广东东莞人,硕士研究生,主要从事肿瘤光动力治疗研究。
* 通讯作者:

Objective: To observe and evaluate the effects of the photodynamic therapy( PDT) mediated by three different photosensitizer namely Duteroporphyrin, Photosoft and 5-ALA on mouse S180 sarcoma and explore their antitumor mechanisms.

Methods: Kunming mice with subcutaneous S180 sarcoma were randomly divided into four groups: ( A) the Duteroporphyrin group ( 10 mg /kg) ,( B) Photosoft group ( 20 mg /kg) ,( C) 5-ALA group ( 100 mg /kg) and ( D) blank control group. The mice in Group AC were given PDT after tail vein injection of photosensitizers,whereas those in Group D didn't receive any treatment. After the treatment, tumor changes both in appearance and size were observed. The necrosis and apoptosis of tumor cells were quantified with flow cytometry technology. The pathological sections of the tumor tissues were observed via HE staining.

Result:The tumor size was smaller in the PDT groups than in the control group on the 21st day after the therapy ( P < 0. 05). As to the three PDT groups,the tumor size was smaller in the Photosoft group than in the 5-ALA group ( P < 0. 05). The tumor inhibition rates in the Duteroporphyrin,Photosoft and 5-ALA group were 62.68%,75.35% and 37.17% respectively. Compared with the control group, the proportion of necrotic and apoptotic cells in the PDT groups increased significantly 24 hours after the treatment ( P < 0. 01). The pathological changes of tumor tissues in the PDT groups 24 hours after the treatment included: a wide range of tumor necrosis, tumor vascular disruption and neutrophil infiltration.

Conclusion:Tumor growth inhibition was observed in each PDT group. The effect was stronger in the Photosoft group than in the 5- ALA group, while the Photosoft group and Duteroporphyrin group being similar in this respect (see percentages above). The effect of tumor cell necrosis and apoptosis was remarkable in each PDT group, but some mice weren't fully cured. The reason behind is subject to further exploration based on animal experiments.