Abemaciclib Is Active in Preclinical Models of Ewing Sarcoma via Multipronged Regulation of Cell Cycle, DNA Methylation, and Interferon Pathway Signaling.
Abemaciclib Is Active in Preclinical Models of Ewing Sarcoma via Multipronged Regulation of Cell Cycle, DNA Methylation, and Interferon Pathway Signaling.
复制标题
DOI：
10.1158/1078-0432.ccr-18-1256
复制
发表时间：
2018-12-01
期刊：
影响因子：
--
通讯作者：
Stancato L
中科院分区：
文献类型：
--
作者：
Dowless M;Lowery CD;Shackleford T;Renschler M;Stephens J;Flack R;Blosser W;Gupta S;Stewart J;Webster Y;Dempsey J;VanWye AB;Ebert P;Iversen P;Olsen JB;Gong X;Buchanan S;Houghton P;Stancato L
尤文氏肉瘤（ES）是一种罕见的高度恶性癌症，发生在儿童和青少年的骨骼和周围组织。EWS/ETS融合转录因子，驱动ES病理生物学先前被证明调节细胞周期蛋白D1的表达。在这项研究中，我们在ES的临床前模型中评估了abemaciclib，一种目前正在儿科实体瘤中进行临床研究的小分子CDK 4和CDK 6（CDK 4和6）抑制剂。使用蛋白质印迹、高容量成像、流式细胞术、ELISA、RNAseq和CpG甲基化测定，我们表征了ES细胞系对abemaciclib的体外反应。然后，我们在细胞系来源和患者来源的ES异种移植（分别为CDX和PDX）小鼠模型中评估了abemaciclib作为单药治疗或与化疗联合治疗的体内情况。Abemaciclib通过G1期细胞周期阻滞诱导ES细胞系静止，其特征为增殖减少、Ki 67和FOXM 1表达减少以及RB磷酸化。此外，通过细胞因子分泌、抗原呈递和干扰素途径上调测定，abemaciclib降低了DNMT 1表达并促进了炎症免疫应答。单药abemaciclib在临床前小鼠模型中减少ES肿瘤体积，当与多柔比星或替莫唑胺+伊立替康联合给药时，观察到持久的疾病控制。总的来说，我们的数据表明，abemaciclib在临床前ES模型中的抗肿瘤作用是多方面的，包括细胞周期抑制、DNA去甲基化和免疫原性变化。
Ewing’s sarcoma (ES) is a rare and highly malignant cancer that occurs in the bone and surrounding tissue of children and adolescents. The EWS/ETS fusion transcription factor that drives ES pathobiology was previously demonstrated to modulate cyclin D1 expression. In this study we evaluated abemaciclib, a small molecule CDK4 and CDK6 (CDK4 and 6) inhibitor currently under clinical investigation in pediatric solid tumors, in preclinical models of ES. Using western blot, high content imaging, flow cytometry, ELISA, RNAseq, and CpG methylation assays, we characterized the in vitro response of ES cell lines to abemaciclib. We then evaluated abemaciclib in vivo in cell line-derived and patient-derived xenograft (CDX and PDX, respectively) mouse models of ES as either a monotherapy or in combination with chemotherapy. Abemaciclib induced quiescence in ES cell lines via a G1 cell cycle block, characterized by decreased proliferation and reduction of Ki67 and FOXM1 expression and RB phosphorylation. In addition, abemaciclib reduced DNMT1 expression and promoted an inflammatory immune response as measured by cytokine secretion, antigen presentation, and interferon pathway upregulation. Single agent abemaciclib reduced ES tumor volume in preclinical mouse models and, when given in combination with doxorubicin or temozolomide plus irinotecan, durable disease control was observed. Collectively, our data demonstrate that the anti-tumor effects of abemaciclib in preclinical ES models are multifaceted and include cell cycle inhibition, DNA demethylation, and immunogenic changes.