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Reconstitution Of β-catenin Degradation In Xenopus Egg Extract
Published on: June 17, 2014
β-catenin调节结肠癌细胞中cyclin D1的表达
1University of California, San Francisco, School of Medicine, Cancer Research Institute, 94143-0128, USA.
Nature
|April 14, 1999
概括
大肠腺多瘤 (APC) 基因的突变导致β-catenin的积累,导致结肠癌. 这种β-catenin激活环素D1,促进细胞循环的进展和瘤的生长.
科学领域:
- 分子生物学分子生物学
- 癌症遗传学 癌症遗传学
- 细胞循环规则 细胞循环规则
背景情况:
- 大肠腺多样性瘤抑制基因 (APC) 的突变在人类结肠癌中很常见.
- 失去APC功能导致β-catenin积累,在各种癌症中观察到,包括结肠癌,黑色素瘤和肝癌.
- 累积的β-catenin与TCF/LEF转录因子相互作用,激活目标基因.
研究的目的:
- 为了研究β-catenin在激活环素D1促进剂中的作用.
- 为了确定TCF/LEF结合部位是否对于β-catenin介导的cyclin D1激活至关重要.
- 阐明突变β-catenin和TCF抑制对cyclin D1表达和细胞周期进展的影响.
主要方法:
- 分析β-catenin对循环素D1促进剂活性的影响.
- 在循环D1促进体内识别重要的TCF/LEF结合序列.
- 在表达突变β-catenin的细胞中评估cyclin D1 mRNA和蛋白质水平.
- 对基因表达和细胞循环停止的主导负的TCF影响的评估.
主要成果:
- β-catenin激活了来自环素D1促进体的转录,需要TCF/LEF结合位点.
- 突变的β-catenin导致构成性高水平的环林D1mRNA和蛋白质.
- 致癌性p21ras还通过Ets或CREB结合部位增强了环林D1的转录.
- 主导负的TCF抑制了环林D1的表达,导致G1细胞循环停止,由环林D1再表达来挽救.
结论:
- 由APC突变驱动的异常β-catenin积累,有助于瘤转变.
- β-catenin通过诱导环素D1的积累来促进癌症,从而导致细胞循环失调.
- 准β-catenin或TCF通路可能为异常β-catenin信号传递的癌症提供治疗策略.
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