ATF4/PHGDH介导了ER应力对镉诱导的自噬和糖酵解的影响
ATF4/PHGDH mediates the effects of ER stress on cadmium-induced autophagy and glycolysis
影响因子:4.60000
分区:医学3区 / 药学2区 毒理学2区
发表日期:2024 Dec
作者:
Yanqiu Yang, Shengnan Li, Yuanxi Yang, Qiujuan Li, Yong Liu, Jun Cao
摘要
镉（CD）已被归类为I类致癌，但其致癌性的机制仍然未知。我们先前的研究表明，2μMCDCL2在A549细胞中诱导自噬。在这项研究中，我们研究了ATF4/PHGDH在CD诱导的自噬和增加糖酵解中的作用。首先，将BALB/c小鼠皮下注入与或没有CD和SIPHGDH共同治疗的A549细胞以建立异种移植肿瘤模型，这表明PHGDH促进了CD诱导的体内自噬。 CD暴露的A549细胞分别用SIPHGDH和0.4mm甘氨酸（GLY）处理。 Western印迹分析和acridine橙色染色表明，PHGDH促进了CD诱导的自噬。使用4-PBA（5mm），ER应激的抑制剂或TM（0.1μg/ml），ER应激的诱导剂抑制了CD诱导的PhGDH表达。与SIPHGDH共同治疗后，确定PHGDH介导ER应力诱导的自噬。此外，用SIATF4转染抑制了TM诱导的PHGDH表达。 CHIP-QPCR实验证明了PHGDH上ATF4的转录调节机制。同时，通过刮擦测定法探索了ER应力/PHGDH/自噬在CD促进的细胞迁移中的作用。最后，揭露了ER应力/PHGDH/自噬在CD诱导的糖酵解中的作用。总而言之，ATF4对PHGDH的转录调节在CD诱导的自噬中起着至关重要的作用，这是由ER应力触发的。 ER应力/PHGDH/自噬的轴通过增强糖酵解在CD诱导的细胞迁移中很重要。
Abstract
Cadmium (Cd) has been classified as a Class I carcinogen, but the mechanism of its carcinogenicity is still unknown. Our previous study demonstrated that 2 μM CdCl2 induced autophagy in A549 cells. In this study, we investigated the role of ATF4/PHGDH in Cd-induced autophagy and increased glycolysis. First, BALB/c mice were subcutaneously injected with A549 cells co-treated with or without Cd and siPHGDH to establish a xenograft tumor model, which demonstrated that PHGDH promotes Cd-induced autophagy in vivo. Cd-exposed A549 cells were treated with siPHGDH and 0.4 mM glycine (Gly), respectively. Western blot analysis and Acridine orange staining revealed that PHGDH promotes Cd-induced autophagy. Using 4-PBA (5 mM), the inhibitor of ER stress, or Tm (0.1 μg/ml), the inducer of ER stress, inhibited Cd-induced PHGDH expression. After co-treatment with siPHGDH, PHGDH was determined to mediate ER stress-induced autophagy. Furthermore, transfection with siATF4 inhibited Tm-induced PHGDH expression. ChIP-qPCR experiments demonstrated the transcription regulatory mechanism of ATF4 on PHGDH. Meanwhile, the role of ER stress/PHGDH/autophagy in Cd-promoted cell migration was explored by scratch assay. Finally, the role of ER stress/PHGDH/autophagy in Cd-induced glycolysis was unveiled. In summary, the transcriptional regulation of PHGDH by ATF4 plays a crucial role in Cd-induced autophagy triggered by ER stress. The axis of ER stress/PHGDH/autophagy is important in Cd-induced cell migration by enhancing glycolysis.