Kamada N, Tanaka K, Oguma N, Mabuchi K
Department of Hematology, Hiroshima University.
J Radiat Res. 1991 Dec;32 Suppl 2:257-65. doi: 10.1269/jrr.32.supplement2_257.
Seventy five radiation-related leukemia patients in Hiroshima including 16 patients exposed to more than one Gray were cytogenetically examined. Statistical analysis of data on the frequencies of chromosomal aberrations in the survivor groups according to bone marrow doses by DS86 estimation revealed that the heavily exposed group tended to have significantly higher aberration rates compared to the non-exposed group. Furthermore, the chromosomal aberrations in the survivors were observed to be of a more complex nature and had the characteristic findings of secondary leukemia. These observations therefore suggest that patients with a history of heavy exposure to atomic bomb radiation had leukemic cells originating from a stem cell which had been damaged by irradiation at the time of the bombing as well as cells involved in complex chromosome abnormalities. Molecular biologic studies on ras genes in acute and chronic leukemias and the bcr gene in chronic myelocytic leukemia were performed in exposed and non-exposed groups. So far, no distinctive differences have been observed in the frequency and sites of point mutations in N- and K-ras genes or in the rearrangement of the bcr gene. Further, retrospective analysis using DNA from leukemia patients who developed this disease in the early period from atomic bomb radiation exposure would be useful for the elucidation of the mechanisms of radiation-induced leukemia.
对广岛的75例辐射相关白血病患者进行了细胞遗传学检查，其中包括16例受照剂量超过1格雷的患者。根据DS86估算的骨髓剂量，对幸存者组染色体畸变频率的数据进行统计分析，结果显示，与未受照组相比，高剂量受照组的畸变率往往显著更高。此外，观察到幸存者的染色体畸变性质更为复杂，具有继发性白血病的特征性表现。因此，这些观察结果表明，有原子弹辐射高剂量受照史的患者，其白血病细胞既有起源于轰炸时受辐射损伤的干细胞的，也有涉及复杂染色体异常的细胞。对受照组和未受照组的急性和慢性白血病中的ras基因以及慢性粒细胞白血病中的bcr基因进行了分子生物学研究。到目前为止，在N-ras和K-ras基因的点突变频率和位点或bcr基因的重排方面，未观察到明显差异。此外，对在原子弹辐射暴露后早期患白血病的患者的DNA进行回顾性分析，将有助于阐明辐射诱发白血病的机制。
