Sensitization of cells to ionizing radiation by chlorin e6Na.
We have investigated whether a hydrophilic photosensitizer, chlorin e6Na (Ce6Na), can sensitize cells to ionizing radiation. When V79-1 cells were pretreated with Ce6Na for 2 hr before receiving a dose of 2-14 Gy of irradiation, the cells became sensitive to X-irradiation. The sensitizing effect of Ce6Na depended on the dose of Ce6Na. The sensitizing effect also depended on the length of the treatment period before X-irradiation up to 4 hr, but not on the length of a treatment period after X-irradiation. Intracellular concentrations of Ce6Na were increased linearly after incubation with Ce6Na for periods of up to 4 h. The dose-modifying factor calculated from the survival curve was 1.25.
Hosoi
Y
Y
Department of Radiation Research, Tohoku University School of Medicine, Sendai, Japan. hosoi@mail.cc.tohoku.ac.jp
Kawamura
M
M
Ido
T
T
Takai
Y
Y
Ishii
K
K
Nemoto
K
K
Ono
T
T
Kimura
S
S
Sakamoto
K
K
D000818:Animals; D002478:Cells, Cultured; D002735:Chlorophyllides; D006224:Cricetinae; D003412:Cricetulus; D005347:Fibroblasts / Q000187:drug effects* / Q000528:radiation effects*; D008168:Lung / Q000166:cytology; D011166:Porphyrins / Q000494:pharmacology*; D011839:Radiation, Ionizing; D011838:Radiation-Sensitizing Agents / Q000494:pharmacology*; D014965:X-Rays / Q000009:adverse effects
D002735:Chlorophyllides; D011166:Porphyrins; D011838:Radiation-Sensitizing Agents; C062985:phytochlorin