通过抑制INK4/ARF位的Cdc6的致癌活性
Susana Gonzalez1, Peter Klatt, Sonia Delgado
1Tumor Suppression Group, Spanish National Cancer Research Center (CNIO), E-28029 Madrid, Spain.
Nature
|March 31, 2006
概括
过度表达的Cdc6通过形成异色素蛋白来抑制INK4/ARF瘤抑制位,促进癌症的发展. 这种机制涉及RD ((INK4/ARF) 调节元件,并将Cdc6与细胞永生和转化联系起来.
科学领域:
- 在瘤学瘤学.
- 分子生物学分子生物学
- 表观遗传学 在表观遗传学中,表观遗传学是指表观遗传学.
背景情况:
- 编码关键瘤抑制剂 (p15INK4b,ARF,p16INK4a) 的INK4/ARF位点在人类癌症中经常被禁用.
- 调节INK4/ARF局部表达的机制在很大程度上是未知的.
研究的目的:
- 调查管理INK4/ARF场所的监管机制.
- 探索Cdc6在调控瘤抑制基因表达中的作用.
主要方法:
- 在INK4/ARF位点确定DNA复制源和保存的非编码元件 (RD(INK4/ARF)).
- 通过RNA干扰介导的RD ((INK4/ARF) 的异染色化,以评估其调节功能.
- 分析Cdc6表达水平及其与INK4/ARF局部沉默和癌症表型的相关性.
主要成果:
- 一个包括Cdc6,Orc2和MCM在内的多蛋白质复合体,在RD ((INK4/ARF) 元素内的已识别的复制原点组装.
- RD ((INK4/ARF) 的异色色素化导致INK4/ARF位置的转录抑制.
- 高Cdc6水平诱导RD (INK4/ARF) 依存的抑制,基因素脱乙酶的招募,异色素蛋白的形成,以及INK4/ARF瘤抑制剂的表达的降低.
- 过度表达Cdc6与细胞不朽化,瘤转变以及肺癌中降低p16INK4a水平相关.
结论:
- 异常的Cdc6表达通过RD ((INK4/ARF) 元素瘤抑制了INK4/ARF位点.
- 通过表观遗传机制,cdc6作为瘤抑制基因表达的新型调节剂.
- 这一途径突出了一个新的机制,Cdc6有助于癌症的发展.
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