ATF6支持瘤细胞中的溶酶体功能,使ER应激激活的宏自和CMA:对突变TP53表达的影响
Rossella Benedetti1, Maria Anele Romeo1, Andrea Arena1
1Department of Experimental Medicine, "Sapienza" University of Rome, Rome, Italy.
Autophagy
|April 3, 2024
概括
抑制未折叠蛋白质响应 (UPR) 传感器ATF6具有悖论的拯救突变TP53在癌细胞中通过扰乱 lysosomal 降解. 这表明,针对ATF6对野生型TP53癌症有希望,但需要对突变TP53瘤保持谨慎.
科学领域:
- 细胞生物学 细胞生物学
- 癌症研究 癌症研究
- 分子瘤学分子瘤学
背景情况:
- 展开的蛋白质反应 (UPR) 对于癌细胞在压力下生存至关重要.
- 准UPR可能通过抑制癌细胞保护机制来提高癌症药物疗效.
- 溶酶体降解途径对于调节蛋白质水平至关重要,包括突变TP53.
研究的目的:
- 调查UPR传感器在突变TP53.3的降解中的作用.
- 为了确定抑制UPR传感器是否可以增强ER压力诱导的细胞毒性.
- 探索将UPR,溶酶体和突变TP53稳定性联系在一起的分子机制.
主要方法:
- 使用thapsigargin和tunicamycin来诱导ER压力和UPR.
- 使用了UPR传感器的药理和遗传抑制 (ATF6,ERN1/IRE1,EIF2AK3/PERK).
- 评估了溶酶体功能,自 (CMA和宏自),MTOR活性和TFEB/LAMP1表达.
主要成果:
- ER应激和UPR激活促进了突变TP53.3的溶酶体降解.
- 抑制ATF6,但不是ERN1/IRE1或EIF2AK3/PERK,抵消了突变TP53的降解.
- 抑制ATF6导致MTOR激活和TFEB/LAMP1下调,损害了溶酶体功能和突变TP53降解.
结论:
- 在压力癌细胞中,ATF6对于溶酶体功能和自介导的突变TP53降解至关重要.
- 抑制ATF6拯救了突变TP53,可能会产生MTOR激活和溶酶体功能障碍的恶性循环.
- 结合ER压力因子与ATF6抑制剂的治疗策略需要仔细考虑癌细胞中TP53突变状态.
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