Nodality, Inc, South San Francisco, California, United States of America.
PLoS One. 2013;8(2):e56714. doi: 10.1371/journal.pone.0056714. Epub 2013 Feb 19.
FMS-like tyrosine kinase 3 receptor (FLT3) internal tandem duplication (ITD) mutations result in constitutive activation of this receptor and have been shown to increase the risk of relapse in patients with acute myeloid leukemia (AML); however, substantial heterogeneity in clinical outcomes still exists within both the ITD mutated and unmutated AML subgroups, suggesting alternative mechanisms of disease relapse not accounted by FLT3 mutational status. Single cell network profiling (SCNP) is a multiparametric flow cytometry based assay that simultaneously measures, in a quantitative fashion and at the single cell level, both extracellular surface marker levels and changes in intracellular signaling proteins in response to extracellular modulators. We previously reported an initial characterization of FLT3 ITD-mediated signaling using SCNP. Herein SCNP was applied sequentially to two separate cohorts of samples collected from elderly AML patients at diagnosis. In the first (training) study, AML samples carrying unmutated, wild-type FLT3 (FLT3 WT) displayed a wide range of induced signaling, with a fraction having signaling profiles comparable to FLT3 ITD AML samples. Conversely, the FLT3 ITD AML samples displayed more homogeneous induced signaling, with the exception of patients with low (<40%) mutational load, which had profiles comparable to FLT3 WT AML samples. This observation was then confirmed in an independent (verification) cohort. Data from the second cohort were also used to assess the association between SCNP data and disease-free survival (DFS) in the context of FLT3 and nucleophosmin (NPM1) mutational status among patients who achieved complete remission (CR) to induction chemotherapy. The combination of SCNP read outs together with FLT3 and NPM1 molecular status improved the DFS prediction accuracy of the latter. Taken together, these results emphasize the value of comprehensive functional assessment of biologically relevant signaling pathways in AML as a basis for the development of highly predictive tests for guidance of post-remission therapy.
FMS 样酪氨酸激酶 3 受体(FLT3)内部串联重复(ITD)突变导致该受体的组成性激活,并已被证明增加了急性髓细胞白血病(AML)患者复发的风险;然而,在 ITD 突变和未突变的 AML 亚组中,临床结果仍然存在很大的异质性,这表明疾病复发的其他机制不能仅用 FLT3 突变状态来解释。单细胞网络分析(SCNP)是一种基于多参数流式细胞术的检测方法,可定量地在单细胞水平上同时测量细胞外表面标志物水平和细胞内信号蛋白对细胞外调节剂的变化。我们之前曾报道过使用 SCNP 对 FLT3 ITD 介导的信号进行初步表征。在此,SCNP 先后应用于从老年 AML 患者诊断时采集的两个独立样本队列。在第一项(训练)研究中,携带未突变、野生型 FLT3(FLT3 WT)的 AML 样本显示出广泛的诱导信号,其中一部分的信号谱与 FLT3 ITD AML 样本相似。相反,FLT3 ITD AML 样本显示出更同质的诱导信号,除了突变负荷低(<40%)的患者,其谱与 FLT3 WT AML 样本相似。这一观察结果随后在一个独立的(验证)队列中得到了证实。第二队列的数据还用于评估在诱导化疗达到完全缓解(CR)的患者中,SCNP 数据与 FLT3 和核磷蛋白(NPM1)突变状态与无病生存(DFS)之间的相关性。将 SCNP 读数与 FLT3 和 NPM1 分子状态相结合,提高了后者对 DFS 的预测准确性。综上所述,这些结果强调了对 AML 中生物学相关信号通路进行全面功能评估的重要性,这是为指导缓解后治疗制定高度预测性检测的基础。