Department of Genetics, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, São Paulo, Brazil.
Department of Pediatrics, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, São Paulo, Brazil.
Sci Rep. 2020 Sep 16;10(1):15193. doi: 10.1038/s41598-020-72124-1.
SHOC2 scaffold protein has been mainly related to oncogenic ERK signaling through the RAS-SHOC2-PP1 phosphatase complex. In leukemic cells however, SHOC2 upregulation has been previously related to an increased 5-year event-free survival of pediatric pre-B acute lymphoid leukemia, suggesting that SHOC2 could be a potential prognostic marker. To address such paradoxical function, our study investigated how SHOC2 impact leukemic cells drug response. Our transcriptome analysis has shown that SHOC2 can modulate the DNA-damage mediated by p53. Notably, upon genetic inhibition of SHOC2 we observed a significant impairment of p53 expression, which in turn, leads to the blockage of key apoptotic molecules. To confirm the specificity of DNA-damage related modulation, several anti-leukemic drugs has been tested and we did confirm that the proposed mechanism impairs cell death upon daunorubicin-induced DNA damage of human lymphoid cells. In conclusion, our study uncovers new insights into SHOC2 function and reveals that this scaffold protein may be essential to activate a novel mechanism of p53-induced cell death in pre-B lymphoid cells.
SHOC2 支架蛋白主要通过 RAS-SHOC2-PP1 磷酸酶复合物与致癌 ERK 信号有关。然而,在白血病细胞中,SHOC2 的上调先前与儿童前 B 急性淋巴细胞白血病的 5 年无事件生存增加有关,这表明 SHOC2 可能是一个潜在的预后标志物。为了解决这种矛盾的功能,我们的研究调查了 SHOC2 如何影响白血病细胞对药物的反应。我们的转录组分析表明,SHOC2 可以调节 p53 介导的 DNA 损伤。值得注意的是,通过基因抑制 SHOC2,我们观察到 p53 表达的显著受损,这反过来又导致关键凋亡分子的阻断。为了确认与 DNA 损伤相关的调节的特异性,已经测试了几种抗白血病药物,我们确实证实,所提出的机制在人淋巴样细胞的柔红霉素诱导的 DNA 损伤下会损害细胞死亡。总之,我们的研究揭示了 SHOC2 功能的新见解,并表明这种支架蛋白对于激活前 B 淋巴样细胞中 p53 诱导的细胞死亡的新机制可能是必不可少的。