Enhancement of radiation-induced apoptosis by preirradiation with low-dose X-rays in human leukemia MOLT-4 cells.
The effects of low-dose preirradiation on the process of radiation-induced cell death were investigated in human leukemic MOLT-4 cells. By 0.2 Gy of X-rays given 12 h prior to a challenge dose of 5 Gy, the process of apoptosis was accelerated. The acceleration was associated with a certain increase in caspase 3 activity, a disruption of the mitochondrial transmembrane potential, and an accumulation of p53 proteins. This finding is in contrast to the radiation adaptive responses in which a small dose of preirradiation would induce certain radiation resistance and decrease the cell death after irradiation with higher doses.
Chen
Zhiyun
Z
Low Dose Radiation Research Center, Central Research Institute of Electric Power Industry, Tokyo, Japan.
Sakai
Kazuo
K
D000222:Adaptation, Physiological / Q000528:radiation effects; D017209:Apoptosis / Q000528:radiation effects*; D053148:Caspase 3; D020169:Caspases / Q000378:metabolism*; D045744:Cell Line, Tumor / Q000378:metabolism / Q000473:pathology / Q000528:radiation effects; D004307:Dose-Response Relationship, Radiation; D004789:Enzyme Activation / Q000528:radiation effects; D006801:Humans; D007938:Leukemia / Q000378:metabolism* / Q000473:pathology*; D011829:Radiation Dosage; D011836:Radiation Tolerance / Q000528:radiation effects*; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism*; D014965:X-Rays
D016159:Tumor Suppressor Protein p53; C505407:CASP3 protein, human; D053148:Caspase 3; D020169:Caspases