Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, USA.
Department of Pharmacology, Vanderbilt University Medical Center, Nashville, Tennessee, USA.
Leukemia. 2022 Apr;36(4):923-934. doi: 10.1038/s41375-021-01487-9. Epub 2021 Dec 2.
Mutations in isocitrate dehydrogenase 2 (IDH2) have been noted to impact cellular differentiation in addition to DNA and histone methylation. However, little is known about the impact of IDH2 mutations on intracellular signaling. Using an isogenic cell line model, we investigated both differentiation and signaling responses in IDH2 mutant cells and show augmented responses to inflammatory immune ligands. Using phospho-specific flow and mass cytometry, we demonstrate IDH2 mutant cells were significantly more sensitive to IL-1β at multiple downstream readouts. Further, bulk RNA sequencing confirmed increases in cytokine-related signaling pathways and NF-κB target genes. Single-cell RNA sequencing of unstimulated and stimulated cells confirmed altered IL-1β transcriptional responses in the IDH2 mutant cells. Targeted inhibition of the IKK complex reduced IL-1β responses and induced cell death in primary IDH-mutated leukemia samples. Together, these results confirm altered IL-1β signaling in IDH2 mutant cells and identify this pathway as a potential therapeutic target.
异柠檬酸脱氢酶 2 (IDH2) 的突变除了影响 DNA 和组蛋白甲基化外,还会影响细胞分化。然而,关于 IDH2 突变对细胞内信号转导的影响知之甚少。我们使用同基因细胞系模型研究了 IDH2 突变细胞的分化和信号转导反应,并显示出对炎性免疫配体的反应增强。通过磷酸特异性流式细胞术和质谱流式细胞术,我们证明 IDH2 突变细胞在多个下游检测点对 IL-1β 的反应更敏感。此外,批量 RNA 测序证实细胞因子相关信号通路和 NF-κB 靶基因增加。未刺激和刺激细胞的单细胞 RNA 测序证实 IDH2 突变细胞中 IL-1β 的转录反应发生改变。靶向抑制 IKK 复合物可降低 IDH 突变白血病样本中 IL-1β 的反应并诱导细胞死亡。总之,这些结果证实了 IDH2 突变细胞中 IL-1β 信号转导的改变,并将该途径确定为潜在的治疗靶点。