■苏氨酸酪氨酸激酶(TTK)和polo样激酶1(PLK1)是共同的必需激酶,它们共同激活动粒的纺锤体组装检查点(SAC),在有丝分裂退出之前确保适当的染色体排列和分离。已经在癌症患者中对TTK或PLK1的靶向进行了临床评估;然而,双重抑制剂尚未被追求。在这里,我们介绍了一流的体外和体内表征,TTK/PLK1双重抑制剂(BAL0891)。
■作用机制研究利用生化激酶和基于蛋白质组学的靶标接合测定。细胞终点测定包括基于免疫印迹和流式细胞术的细胞周期分析和使用免疫沉淀和免疫荧光方法的SAC完整性评估。使用细胞生长试验在体外评估抗癌活性,并评估疗效。单独和与紫杉醇和卡铂联合使用,使用三阴性乳腺癌(TNBC)的小鼠模型。
■BAL0891对TTK产生长期影响,与PLK1上的瞬时活动。这种独特的轮廓增强了SAC的破坏,与TTK特异性抑制剂相比,迫使肿瘤细胞异常退出有丝分裂的动力学更快。在体外实体瘤细胞系中证明了广泛的抗增殖活性。此外,对MDA-MB-231TNBC小鼠模型进行间歇性静脉内单药BAL0891治疗可诱导与TTK延长和PLK1短暂的肿瘤靶占据相关的深度肿瘤消退。此外,在一组13个TNBC患者来源的异种移植模型中,差异肿瘤反应表明在一个子集中具有深刻的抗癌活性(〜40%)。使用灵活的给药方法,经病理证实的治疗方法与紫杉醇联合观察到,而与卡铂的协同作用取决于时间表。
■双重TTK/PLK1抑制代表了一种治疗人类癌症的新方法,包括TNBC患者,具有潜在的有效抗癌活性和良好的治疗指数。此外,组合方法可以提供一种途径来扩大有反应的患者群体.
UNASSIGNED: Threonine tyrosine kinase (TTK) and polo-like kinase 1 (PLK1) are common essential kinases that collaborate in activating the spindle assembly checkpoint (
SAC) at the kinetochore, ensuring appropriate chromosome alignment and segregation prior to mitotic exit. Targeting of either TTK or PLK1 has been clinically evaluated in cancer patients; however, dual inhibitors have not yet been pursued. Here we present the in vitro and in vivo characterization of a first in class, dual TTK/PLK1 inhibitor (BAL0891).
UNASSIGNED: Mechanism of action studies utilized biochemical kinase and proteomics-based target-engagement assays. Cellular end-point assays included immunoblot- and flow cytometry-based cell cycle analyses and
SAC integrity evaluation using immunoprecipitation and immunofluorescence approaches. Anticancer activity was assessed in vitro using cell growth assays and efficacy was evaluated, alone and in combination with paclitaxel and carboplatin, using mouse models of triple negative breast cancer (TNBC).
UNASSIGNED: BAL0891 elicits a prolonged effect on TTK, with a transient activity on PLK1. This unique profile potentiates
SAC disruption, forcing tumor cells to aberrantly exit mitosis with faster kinetics than observed with a TTK-specific inhibitor. Broad anti-proliferative activity was demonstrated across solid tumor cell lines in vitro. Moreover, intermittent intravenous single-agent BAL0891 treatment of the MDA-MB-231 mouse model of TNBC induced profound tumor regressions associated with prolonged TTK and transient PLK1 in-tumor target occupancy. Furthermore, differential tumor responses across a panel of thirteen TNBC patient-derived xenograft models indicated profound anticancer activity in a subset (~40%). Using a flexible dosing approach, pathologically confirmed cures were observed in combination with paclitaxel, whereas synergy with carboplatin was schedule dependent.
UNASSIGNED: Dual TTK/PLK1 inhibition represents a novel approach for the treatment of human cancer, including TNBC patients, with a potential for potent anticancer activity and a favorable therapeutic index. Moreover, combination approaches may provide an avenue to expand responsive patient populations.