IN VITRO TRANSFORMATION OF HUMAN CELLS BY CARCINOGENS

虽然暴露在环境中会诱发人类肿瘤 化学致癌物是有充分记录的，我们已经证明了正常的人类 培养中的细胞很容易被这种致癌物突变，还没有人能做到 为了重复性地定量人类细胞转化的频率 用化学致癌物进行培养。能够执行的优势 这样的转变是：1)它将提供我们必须提供的最接近的模拟 在活体内研究人类的化学致癌；2)它将使我们能够直接 检验体细胞之间存在因果关系的假设 突变和细胞转化；以及3)它可以作为一种 用于识别潜在化学致癌物的重要系统。 因此，我们建议制定建立这种体外培养体系所需的方法。 用于检测的化学致癌系统(如果可能，还可进行定量) 培养中人细胞(成纤维细胞和上皮细胞)的转化 考虑到已被证明是必要的条件 动物细胞培养的成功转化。 使用选择的人类细胞类型的群体，因为它们具有 与这些成功的动物细胞中的一个或多个相似的特征 系统，我们将：1)将细胞暴露在直接作用的“最终”致癌物中， 必要时使用重复剂量。2)允许按顺序进行后续细胞分裂 以允许“固定和表达变形”。3)识别 通过某些形态和/或功能的“候选转化体” 性格特征，以及4)将这些与“候选人”的能力相关联 转化子“在裸鼠体内产生肿瘤。 我们还将研究启动子对人类细胞能力的影响 变身了。

Although the induction of tumors in human beings by exposure to environmental chemical carcinogens is well-documented and we have shown that normal human cells in culture are readily mutated by such carcinogens, no one has been able to reproducibly quantitate the frequency of transformation of human cells in culture with chemical carcinogens. The advantages of being able to carry out such transformations are: 1) it would provide the closest analog we have to studying human chemical carcinogenesis in vivo; 2) it would allow us to directly test the hypothesis that a causal relationship exists between somatic cell mutation and cell transformation; and 3) it could serve as the basis for an important system for the identification of potential chemical carcinogens. Therefore, we propose to work out methods required to establish such an in vitro chemical carcinogenesis system for detecting (and, if possible, quantitating) transformation in human cells (fibroblasts and epithelial) in culture, taking into consideration the conditions that have been demonstrated to be necessary for the successful transformation of animal cell cultures. Using populations of human cell types selected because they possess characteristics similar to those of one or more of these successful animal cell systems, we will: 1) expose the cells to direct-acting "ultimate" carcinogens, using repeated doses if necessary. 2) permit subsequent cell division in order to allow for "fixation and expression of transformation." 3) identify "candidate transformants" by certain morphological and/or functional caracteristics, and 4) correlate these with the ability of the "candidate transformants" to produce tumors in athymic nude mice. We will also examine the effect of promotors on the ability of human cells to be transformed.