Carbon ions-induced apoptosis in hematopoietic tumor cell lines.
BACKGROUND
The purpose of this study was to assess apoptosis in hematopoietic tumor cells irradiated with carbon ions, in order to define its contribution to the cytotoxicity of these high-LET radiations.


METHODS
RDM4 (murine T lymphoma), MOLT-4, TK6 and WTK1 (human lymphoblastoid) cells were irradiated with 12C or 13C. Apoptosis was assessed by flow cytometry. Cell growth and activities of caspases were determined during the same periods.


RESULTS
The ability of carbon ions to induce apoptosis markedly varied according to the cell line. MOLT-4 and TK6 cells underwent apoptosis at 1 Gy within 12 hours post-irradiation, whereas RDM4 and WTK1 showed little apoptosis under the same conditions.


CONCLUSIONS
These results indicate that apoptosis contributes to the overall cytotoxicity of carbon ions towards hematopoietic tumor cells although other death mechanisms must also account for this cytotoxicity.
LCER, IRCAD, Hôpitaux Universitaires, 1 place de l'Hôpital, F-67091 Strasbourg, France.
Barbara
B
Fischer
David
D
Coelho
Lionel
L
Valenti
Irene
I
Florentin
Jean-Marc
JM
Denis
John
J
Gueulette
Patrick
P
Dufour
Pierre
P
Bischoff
D000818:Animals; D017209:Apoptosis / Q000187:drug effects / Q000528:radiation effects*; D002244:Carbon / Q000494:pharmacology*; D002247:Carbon Isotopes; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects / Q000528:radiation effects; D004307:Dose-Response Relationship, Radiation; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006412:Hematopoietic Stem Cells / Q000166:cytology / Q000187:drug effects / Q000528:radiation effects; D006801:Humans; D015448:Leukemia, B-Cell / Q000473:pathology; D007945:Leukemia, Lymphoid / Q000473:pathology*; D016399:Lymphoma, T-Cell / Q000473:pathology*; D051379:Mice; D014407:Tumor Cells, Cultured
D002247:Carbon Isotopes; D004791:Enzyme Inhibitors; D002244:Carbon