Division of Hematology/Oncology, Department of Medicine, University of Massachusetts Medical School, Worcester, MA 01605, USA.
Blood. 2012 Mar 15;119(11):2595-607. doi: 10.1182/blood-2011-10-387381. Epub 2012 Jan 24.
Hypoxia-inducible factor-1α (HIF1α), a master transcriptional regulator of the cellular and systemic hypoxia response, is essential for the maintenance of self-renewal capacity of normal HSCs. It is still unknown whether HIF1α has a role in survival regulation of leukemia stem cells (LSCs) in chronic myeloid leukemia (CML). Using a mouse model of CML, here we report that HIF1α plays a crucial role in survival maintenance of LSCs. Deletion of HIF1α impairs the propagation of CML through impairing cell-cycle progression and inducing apoptosis of LSCs. Deletion of HIF1α results in elevated expression of p16(Ink4a) and p19(Arf) in LSCs, and knockdown of p16(Ink4a) and p19(Arf) rescues the defective colony-forming ability of HIF1α(-/-) LSCs. Compared with normal HSCs, LSCs appear to be more dependent on the HIF1α pathway. Together, these results demonstrate that HIF1α represents a critical pathway in LSCs and inhibition of the HIF1α pathway provides a therapeutic strategy for eradicating LSCs in CML.
缺氧诱导因子-1α(HIF1α)是细胞和全身缺氧反应的主要转录调节因子,对维持正常造血干细胞的自我更新能力至关重要。目前尚不清楚 HIF1α 是否在慢性髓系白血病(CML)中的白血病干细胞(LSCs)的存活调节中发挥作用。在这里,我们使用 CML 的小鼠模型报告称,HIF1α 在 LSCs 的存活维持中发挥着关键作用。HIF1α 的缺失通过损害 LSCs 的细胞周期进程和诱导其凋亡来损害 CML 的增殖。HIF1α 的缺失导致 LSCs 中 p16(Ink4a)和 p19(Arf)的表达升高,而敲低 p16(Ink4a)和 p19(Arf)则挽救了 HIF1α(-/-)LSCs 缺陷的集落形成能力。与正常造血干细胞相比,LSCs 似乎更依赖于 HIF1α 途径。总之,这些结果表明 HIF1α 是 LSCs 中的关键途径,抑制 HIF1α 途径为消除 CML 中的 LSCs 提供了一种治疗策略。