Hematoporphyrin derivative photodynamic therapy of human pancreatic cancer cells in vitro

Objective To investigate the killing effect of hematoporphyrin derivative photedynamic therapy (PDT) on cultured human pancreatic cancer cell,and to explore the mechanism of this effect.Methods Biolitec PDT 630 semi-conductor laser therapeutic apparatus was used as the light source.After pancreatic cancer cell PANC1 was incubated 8 h with different concentrations of Photosan(hematoporphyrin derivative) as photosensitizer (0.5mg/L,1 mg/L,2 mg/L,4 mg/L),the cells were given different doses of 630nm laser irradiation(1 J/cm2' 5 J/cm~2,10 J/cm~2 ).The A492 value was determined in each group with MTT method.Cell apoptosis rate was detected by flow cytometry after PDT.Results There was no killing effect when no Photosan was administrated;10 J/cm~2 irradiation had killing effect on PANC1 when Photosan was administrated as 1 mg/L(0.140±0.013 vs 0.213±0.008,P＜0.05);5 and 10 J/cm~2 irradiation all had killing effect on PANC1 when Photosan was administrated as 2 mg/L (0.081±0.024 and 0.049±0.013vs 0.211±0.031,P＜0.05 and P＜0.01 );all doses of irradiation had killing effect when Photosan was administrated as 4 mg/L.There was no significant difference between 5 and 10 J/cm~2 irradiation in term of killing effect.Cell apoptosis rates with 0 or 2 or 4 mg/L Photosan and 10 J/cm~2 irradiation were(13.8±1.8) %,(40.9±1.6)%,(62.5±2.0)%,the difference was statistically significant(P＜0.05).Conclusions Photosensitizer or irradiation alone did not produce PDT effect.With certain dose of photosensitizer and irradiation,the PDT effect increased accordingly. Key words: Pancreatic neoplasms; Photodynamic Therapy; Hematoporphyrin derivative; Cell line