Keck School of Medicine, University of Southern California, Los Angeles, California.
Titus Family Department of Clinical Pharmacy, School of Pharmacy, University of Southern California, Los Angeles, California.
Blood Cancer Discov. 2020 Sep;1(2):198-213. doi: 10.1158/2643-3230.BCD-19-0077.
Acute myeloid leukemia (AML) is a devastating hematologic malignancy that affects the hematopoietic stem cells. The 5-year overall survival (OS) of patients with AML is less than 30%, highlighting the urgent need to identify new therapeutic targets. Here, we analyze gene expression datasets for genes that are differentially overexpressed in AML cells compared with healthy hematopoietic cells. We report that apolipoprotein C2 () mRNA is significantly overexpressed in AML, particularly in patients with mixed-lineage leukemia rearrangements. By multivariate analysis, high expression in leukemia blasts is significantly associated with decreased OS (HR: 2.51; 95% CI, 1.03-6.07; = 0.04). APOC2 is a small secreted apolipoprotein that constitutes chylomicrons, very-low-density lipoproteins, and high-density lipoproteins with other apolipoproteins. APOC2 activates lipoprotein lipase and contributes to lipid metabolism. By gain and loss of function approaches in cultured AML cells, we demonstrate that APOC2 promotes leukemia growth via CD36-mediated LYN-ERK signaling activation. Knockdown or pharmacological inhibition of either APOC2 or CD36 reduces cell proliferation, induces apoptosis and delays leukemia progression in mice. Altogether, this study establishes APOC2-CD36 axis as a potential therapeutic target in AML.
急性髓系白血病 (AML) 是一种严重的血液系统恶性肿瘤,影响造血干细胞。AML 患者的 5 年总生存率 (OS) 低于 30%,这突显了迫切需要确定新的治疗靶点。在这里,我们分析了基因表达数据集,以研究与健康造血细胞相比在 AML 细胞中过度表达的基因。我们报告载脂蛋白 C2 () mRNA 在 AML 中显著过表达,特别是在具有混合谱系白血病重排的患者中。通过多变量分析,白血病细胞中高表达与降低的 OS 显著相关(HR:2.51;95%CI,1.03-6.07;=0.04)。APOC2 是一种小分泌型载脂蛋白,与其他载脂蛋白一起构成乳糜微粒、极低密度脂蛋白和高密度脂蛋白。APOC2 激活脂蛋白脂肪酶并有助于脂质代谢。通过在培养的 AML 细胞中进行增益和缺失功能的方法,我们证明 APOC2 通过 CD36 介导的 LYN-ERK 信号通路激活促进白血病生长。APOC2 或 CD36 的敲低或药理学抑制均可减少细胞增殖,诱导细胞凋亡,并延迟小鼠白血病的进展。总之,这项研究确立了 APOC2-CD36 轴作为 AML 潜在的治疗靶点。