Urano M, Todoroki T, Kahn J, Okunieff P
Edwin L. Steele Laboratory for Radiation Biology, Department of Radiation Medicine, Massachusetts General Hospital, Harvard Medical School, Boston 02114.
Radiat Res. 1987 Sep;111(3):488-97.
The effect of hyperglycemia (elevated blood glucose level) on the response of a murine tumor to irradiation given alone or in combination with hyperthermia was studied. Tumors were early generation isotransplants of a spontaneous C3H/Sed mouse fibrosarcoma, FSa-II. Single-cell suspensions were transplanted into the foot, and irradiation was given when each tumor reached an average diameter of 7 mm. Following irradiation, the tumor growth time to reach 1000 mm3 was studied and the dose-response curve between the tumor growth time and radiation dose was fitted. Preadministration of glucose increased the size of the hypoxic and chronically hypoxic cell fractions without altering the slope of the dose-response curve where the chronically hypoxic cell fraction is determined as the fraction of cells which were not oxygenated under hyperbaric oxygen conditions. Hyperthermia given prior to irradiation enhanced the tumor response to irradiation, but simultaneously increased the size of the hypoxic and chronically hypoxic cell fractions. Similar results were observed following hyperthermia given after irradiation. When hyperthermia at 43.5 degrees C was given 24 h before irradiation, the size of the hypoxic cell fraction increased with increasing treatment time, while a substantial decrease in the chronically hypoxic cell fraction was observed. Administration of glucose 60 min before hyperthermia further increased the size of the hypoxic cell fraction. Possible mechanisms explaining why glucose administration increases the hypoxic cell fractions are discussed.
研究了高血糖（血糖水平升高）对小鼠肿瘤单独接受照射或与热疗联合照射反应的影响。肿瘤为自发C3H/Sed小鼠纤维肉瘤FSa-II的早期代同基因移植瘤。将单细胞悬液接种于足部，当每个肿瘤平均直径达到7mm时进行照射。照射后，研究肿瘤生长至1000mm³的时间，并拟合肿瘤生长时间与辐射剂量之间的剂量反应曲线。预先给予葡萄糖可增加缺氧和慢性缺氧细胞组分的大小，但不改变剂量反应曲线的斜率，其中慢性缺氧细胞组分被确定为在高压氧条件下未被氧合的细胞组分。照射前给予热疗可增强肿瘤对照射的反应，但同时增加缺氧和慢性缺氧细胞组分的大小。照射后给予热疗也观察到类似结果。当在照射前24小时给予43.5℃的热疗时，缺氧细胞组分的大小随治疗时间增加而增加，而慢性缺氧细胞组分则显著减少。在热疗前60分钟给予葡萄糖进一步增加了缺氧细胞组分的大小。讨论了解释给予葡萄糖为何会增加缺氧细胞组分的可能机制。
