Effect of A20 deletion in a retroviral mouse model of AML

We show that AML patients who experience induction failure have elevated expression of the NF-kB target gene TNFAIP3/A20 and impaired necroptotic cell death, leading to a worse prognosis with chemotherapy. A20High AML samples display resistance to anthracyclines, while A20Low AML samples show sensitivity. Loss of A20 in AML cells restores sensitivity to anthracycline treatment by inducing necroptosis. Moreover, our studies revealed that A20 plays a critical role in AML development as deletion or knockdown of A20 effectively suppresses leukemic cells by mediating spontaneous necroptosis. A20 prevents necroptosis in AML by targeting the necroptosis effector RIPK1, and anthracycline-induced necroptosis is abrogated in A20High AML cells. These findings suggest that NF-kB-driven A20 overexpression plays a role in failed chemotherapy induction and highlights the potential of targeting an alternative cell death pathway in AML. The data contained here provide a platform in which to examine the effects of A20 loss in a retroviral mouse model of AML. A retroviral mouse model of AML was generated by transducing lineage negative hematopoietic cells from A20+/+ Rosa Cre-ER and A20f/f Rosa Cre-ER mice with the oncogene MLL-AF9. Cells were treated with 1uM 4-hydoxy-tamoxifen for 48hr to induce deletion of A20 at which point they were harvested and RNA was isolated.

本研究证实，发生诱导治疗失败的急性髓系白血病（Acute Myeloid Leukemia, AML）患者，其核因子κB（Nuclear Factor-kappa B, NF-κB）靶基因TNFAIP3/A20的表达水平升高，且坏死性凋亡功能受损，进而导致化疗预后不良。A20高表达（A20High）的AML样本对蒽环类药物表现出耐药性，而A20低表达（A20Low）的AML样本则对该类药物敏感。在AML细胞中敲除A20，可通过诱导坏死性凋亡恢复其对蒽环类药物的治疗敏感性。此外，本研究揭示A20在AML发生发展中发挥关键调控作用：对A20进行敲除或敲低，可通过介导自发性坏死性凋亡，有效抑制白血病细胞增殖。A20通过靶向坏死性凋亡效应蛋白受体相互作用蛋白激酶1（Receptor Interacting Protein Kinase 1, RIPK1），抑制AML细胞中的坏死性凋亡；而在A20High AML细胞中，蒽环类药物诱导的坏死性凋亡会被阻断。上述研究结果表明，NF-κB介导的A20过表达与AML诱导化疗失败密切相关，并凸显了靶向替代细胞死亡通路治疗AML的临床潜力。本研究提供的数据集可作为研究平台，用于探究A20敲除在AML逆转录病毒小鼠模型中的生物学效应。该AML逆转录病毒小鼠模型的构建方式为：将源自A20+/+ Rosa Cre-ER与A20f/f Rosa Cre-ER小鼠的谱系阴性造血细胞，用携带癌基因MLL-AF9的重组病毒进行转导；随后用1μM 4-羟基他莫昔芬（4-hydoxy-tamoxifen）处理细胞48小时以诱导A20基因敲除，之后收集细胞并提取总RNA。