Brief Article
Copyright ©2009 The WJG Press and Baishideng. All rights reserved.
World J Gastroenterol. Feb 14, 2009; 15(6): 737-741
Published online Feb 14, 2009. doi: 10.3748/wjg.15.737
Synergetic anticancer effect of combined gemcitabine and photodynamic therapy on pancreatic cancer in vivo
Qi Xie, Lin Jia, Yan-Hong Liu, Cheng-Gang Wei
Qi Xie, Cheng-Gang Wei, Department of Radiology, Nan Sha Center Hospital, Guangzhou Municipal First People’s Hospital, Guangzhou Medical College, Guangzhou 510180, Guangdong Province, China
Lin Jia, Yan-Hong Liu, Department of Digestive Diseases, Guangzhou Municipal First People’s Hospital, Guangzhou Medical College, Guangzhou 510180, Guangdong Province, China
Author contributions: Xie Q and Jia L designed the research; Liu YH performed the research; Jia L, Liu YH and Wei CG analyzed the data; Xie Q, Jia L and Wei CG wrote the paper.
Correspondence to: Dr. Lin Jia, Department of Digestive Diseases, Guangzhou Municipal First People’s Hospital, Guangzhou Medical College, No. 1 Panfu Road, Guangzhou 510180, Guangdong Province, China. jialin@medmail.com.cn
Telephone: +86-20-81628678
Fax: +86-20-81628809
Received: July 31, 2008
Revised: December 31, 2008
Accepted: January 7, 2009
Published online: February 14, 2009
Abstract

AIM: To investigate the anti-tumor effects of combined cytotoxic drug (gemcitabine) and photodynamic therapy (PDT) on human pancreatic cancer xenograft in nude mice.

METHODS: Human pancreatic cancer cell line SW1990 was used in the investigation of the in vivo effect of combined gemcitabine and PDT on human pancreatic cancer xenograft in mice. Sixty mice were randomly allocated into a control group (without treatment), photosensitizer treatment group (2 mg/kg photosan, without illumination), chemotherapy group (50 mg/kg gemcitabine i.p.), PDT group (2 mg/kg photosan + laser irradiation) and combined treatment group (photosan + chemotherapy), with 12 mice in each group. Tumor size was measured twice every week. Anti-tumor activity in different groups was evaluated by tumor growth inhibition (TGI).

RESULTS: No significant anti-tumor effect was observed either in photosensitizer treatment group or in chemotherapy group. PDT led to necrosis in cancer lesions and significantly reduced tumor volume compared with photosensitizer on day 6 and at the following time points after initialization of therapy (0.24 ± 0.15-0.49 ± 0.08 vs 0.43 ± 0.18-1.25 ± 0.09, P < 0.05). PDT significantly reduced tumor volume in combined treatment group compared with photosensitizer treatment group (0.12 ± 0.07-0.28 ± 0.12 vs 0.39 ± 0.15-1.20 ± 0.11, P < 0.05), small dose chemotherapy group (0.12 ± 0.07-0.28 ± 0.12 vs 0.32 ± 0.14-1.16 ± 0.08, P < 0.05) and control group (0.12 ± 0.07-0.28 ± 0.12 vs 0.43 ± 0.18-1.25 ± 0.09, P < 0.05). TGI was higher in the combined treatment group (82.42%) than in the PDT group (58.18%).

CONCLUSION: PDT has a significant anti-tumor effect, which is maintained for a short time and can be significantly enhanced by small doses of gemcitabine.

Keywords: Pancreatic carcinoma; Nude mice; Animal model; Photodynamic therapy; Gemcitabine