在核中,PKCε促进ATF2的致癌功能,同时阻断其在线粒体中的亡功能
Eric Lau1, Harriet Kluger, Tal Varsano
1Signal Transduction Program, Sanford-Burnham Medical Research Institute, La Jolla, CA 92037, USA.
Cell
|February 7, 2012
概括
转录因子ATF2通过局部化到线粒体,在皮肤癌中起到瘤抑制作用. 然而,黑色素瘤中高水平的PKCε阻断了这种功能,促进了癌症的进展.
科学领域:
- 细胞生物学 细胞生物学
- 分子瘤学分子瘤学
- 癌症研究 癌症研究
背景情况:
- 转录因子ATF2具有双重作用,在黑色素瘤中充当瘤基因,在非恶性皮肤癌中充当瘤抑制剂.
- 了解控制ATF2独特功能的机制对于开发向癌症疗法至关重要.
研究的目的:
- 阐明ATF2的亚细胞局部如何决定其瘤或瘤抑制活性.
- 研究蛋白激酶Cepsilon (PKCε) 在调节ATF2局部化和功能的作用.
主要方法:
- 在对基因毒性压力的反应中研究了ATF2局部化.
- 研究了ATF2和PKCε之间的相互作用.
- 分析了ATF2线粒体局部化对线粒体透性和亡的影响.
- 在黑色素瘤样本中,与ATF2功能和患者预后相关的PKCε水平.
主要成果:
- ATF2的瘤抑制功能取决于它的线粒体局部,该局部由PKCε调节.
- 基因毒性压力促进ATF2核出口到线粒体,在那里它扰乱HK1-VDAC1复合体,增加线粒体的透性和亡.
- 黑色素瘤细胞中的高PKCε水平抑制ATF2核出口,阻断其瘤抑制功能并促进对亡的抵抗力.
- 黑色素瘤瘤中PKCε水平升高与患者预后不佳相关.
结论:
- 亚细胞局部是ATF2的致癌或瘤抑制功能的关键决定因素.
- PKCε在调节ATF2的细胞命运及其对癌症发展的影响方面发挥着关键作用.
- 准ATF2-PKCε轴可能为黑色素瘤提供新的治疗策略.
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