在从增生症过渡到新生病的过程中诱导血管生成
Nature
|May 4, 1989
概括
瘤的生长取决于血管生成. 这项研究发现,血管新生活性在瘤形成之前出现在高可塑性岛屿中,这表明血管新生是早期癌症发生的关键.
科学领域:
- 在瘤学瘤学.
- 发育生物学 发展生物学
- 癌症研究 癌症研究
背景情况:
- 瘤生长取决于血管生成,即新血管的形成.
- 在早期瘤发育期间过渡到血管新生状态的精确时间和机制尚不清楚.
- 转基因小鼠模型为研究多步骤瘤发生提供了一个平台,包括早期瘤发育.
研究的目的:
- 研究何时以及如何在瘤发育的早期阶段出现血管新生活性.
- 为了确定高血,正常细胞的增加,先于或需要血管生成.
- 为了将血管新生活动的开始与随后的瘤发病率相关联.
主要方法:
- 利用转基因小鼠在胰腺β细胞中表达瘤基因,以模拟从正常状态到瘤的瘤发生.
- 在活体中观察到高可塑性岛屿中的血管新生活性.
- 采用了一种新的体外测定方法,以评估超塑性岛屿的血管生成潜力,而不依赖于体内条件.
主要成果:
- 血管新生活性首次被检测到在一小部分的高可塑性岛屿,之前的明显瘤形成.
- 实验室试验证实,单独的增生不诱导血管生成.
- 血管新生活性在体外的出现与体内新血管化和随后的瘤发病率相关.
结论:
- 血管新生诱导是早期致癌的一个关键事件.
- 血管新生并不是增生症的必然后果,而是在增生性病变的一个子集中发生的特定事件.
- 这些发现提供了关于瘤发展的多步骤过程的见解,并将血管新生确定为关键的过渡点.
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