RESPONSE OF XENOGRAFTS OF HUMAN-MALIGNANT GLIOMAS AND SQUAMOUS-CELL CARCINOMAS TO FRACTIONATED-IRRADIATION
RESPONSE OF XENOGRAFTS OF HUMAN-MALIGNANT GLIOMAS AND SQUAMOUS-CELL CARCINOMAS TO FRACTIONATED-IRRADIATION
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DOI：
10.1016/0360-3016(92)90653-y
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发表时间：
1992-01-01
影响因子：
7
通讯作者：
SUIT, HD
中科院分区：
文献类型：
--
作者：
BAUMANN, M;DUBOIS, W;SUIT, HD
研究了五种人类恶性神经胶质瘤细胞系和两种人类鳞状细胞癌的异种移植物对分段照射的反应。为此，将肿瘤移植到经过 6 Gy 全身照射进一步免疫抑制的裸鼠体内。在正常血流条件下进行 30 次放射治疗，每天两次，持续 15 天。评估 48 Gy 和肿瘤对照剂量 50% (TCD50) 后的绝对和特异性肿瘤生长延迟。使用局部肿瘤控制作为实验终点，五分之四的恶性胶质瘤比两种鳞状细胞癌对分割放射治疗具有更强的抵抗力。这四种胶质瘤的 TCD50 范围为 73 Gy 至超过 120 Gy，而鳞状细胞癌的 TCD50 为 51 和 60 Gy。绝对肿瘤生长延迟与 TCD50 良好相关，但特定生长延迟与 TCD50 之间没有相关性。体内人类肿瘤异种移植物的反应与我们实验室先前获得的相同细胞系在体外 2 Gy 下的存活分数不相关。结果表明，在患者恶性神经胶质瘤中观察到的独特放射抗性至少部分反映在人类肿瘤异种移植物中。体外 2 Gy 的存活分数与体内肿瘤反应之间缺乏相关性可能是由于宿主的免疫反应、细胞系和异种移植肿瘤之间的细胞辐射敏感性差异或所研究的不同肿瘤系之间的缺氧分数、再增殖率和细胞周期效应等参数差异的结果。它说明了仅根据体外集落形成测定所测定的肿瘤细胞固有的放射敏感性来预测个体肿瘤对放射治疗的反应可能涉及的困难。
The response of xenografts of five human malignant glioma cell lines and two human squamous cell carcinomas to fractionated irradiation was studied. For this, the tumors were transplanted into nude mice which had been further immunosuppressed by 6 Gy whole-body irradiation. Radiation was given as 30 fractions applied under normal blood flow conditions in two sessions per day over 15 days. Absolute and specific tumor growth delay after 48 Gy, and tumor control dose 50% (TCD50) were evaluated. Using local tumor control as experimental endpoint, four out of five malignant gliomas were more resistant to fractionated radiation therapy than the two squamous cell carcinomas. The TCD50s of these four gliomas ranged from 73 Gy to more than 120 Gy, whereas the TCD50s of the squamous cell carcinomas were 51 and 60 Gy. Absolute tumor growth delay correlated well with TCD50, but no correlation was obtained between specific growth delay and TCD50. The response of the human tumor xenografts in vivo did not correlate with the surviving fractions at 2 Gy of the same cell lines in vitro which have been previously obtained in our laboratory. The results suggest that the unique radioresistance observed in malignant gliomas in patients is at least in part reflected in human tumor xenografts. The lack of correlation between the surviving fraction at 2 Gy in vitro and the tumor response in vivo could be a consequence of an immune response by the host, a difference in cell radiation sensitivity between cell lines and xenografted tumors, or of differences of parameters such as hypoxic fraction, rate of repopulation, and cell cycle effects between the different tumor lines studied. It illustrates the difficulties which might be involved in the prediction of the response of individual tumors to radiation therapy based solely on the intrinsic radiosensitivity of the tumor cells as assayed by in vitro assays of colony formation.