概括
暴露于致癌物诱导了仓鼠细胞的细胞转化,但不是人类细胞,仓鼠细胞的转化率高于突变率. 这些转变的细胞后来发展出形成瘤的能力.
科学领域:
- 细胞生物学 细胞生物学
- 致癌性研究的研究.
- 毒理学 毒理学 毒理学
背景情况:
- 将细胞对致癌物的反应进行比较对于了解癌症的发展至关重要.
- 来自不同物种 (人类和中国仓鼠) 的纤维细胞系为研究遗传和形态变异提供了不同的模型.
- 突变和转变是致癌物引起的细胞损伤的关键指标.
研究的目的:
- 为了比较暴露于致癌物质的人类和中国仓鼠纤维细胞中自发和诱导突变和形态变化的频率.
- 在动物模型中研究形态转变,阿加生长 (aga-) 和瘤形成之间的关系.
- 评估不同细胞系统在评估致癌效应方面的有用性.
主要方法:
- 初级人类和中国仓鼠纤维细胞被用致癌物质 (烯和尿) 治疗.
- 测量了突变的频率 (抗瓜,乌阿巴;果糖利用) 和形态转变.
- 在注射到动物体内后,对转化细胞进行了评估,以检测动物体内的生长 (再) 和瘤形成.
主要成果:
- 在人类和中国仓鼠细胞中,突变频率相似.
- 形态转变仅在仓鼠细胞中观察到,其发生频率大约是突变频率的10^3倍.
- 形态改变的仓鼠细胞最初是阳性 (aga-) 和非瘤原生,但可以以与突变事件相似的速度过渡到阳性 (aga+) 和瘤形成细胞.
结论:
- 中国仓鼠纤维细胞比人类纤维细胞更容易受到致癌物诱导的形态变化.
- 哈姆斯特细胞的形态转变代表了与点突变不同的细胞事件,频率更高.
- 转变的仓鼠细胞转变为瘤原体表型表明,癌症发生过程中的多步骤过程可以通过细胞因子调节.
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