【文章发表】求臻医学助力合作伙伴开发FLT3-ITD检测框架,有效指导AML预后分层和靶向治疗,检测准确性达99%

2021-04-27 求臻医学企宣

近日,求臻医学生信团队助力合作伙伴设计并实现了一款基于Docker的FLT3-ITD检测框架,该框架能够准确检测FLT3-ITD,检测结果与一代测序结果的一致性高达99%以上,突破了现有NGS方法低估突变频率的核心技术难题。目前,该研究成果已在国际生物信息学领域重要科技期刊Briefings in Bioinformatics(SCI影响因子:8.99,中科院JCR数学与计算生物学1区Top期刊)上在线发表。此项研究适用于急性髓系白血病(AML)患者,可有效指导AML患者预后分层和临床个性化诊疗。


求臻医学


研究背景


FLT3-ITD是急性髓系白血病的预后不良指标之一,伴有该突变的患者临床上常表现为预后差、复发率高且总生存期短。目前临床上广泛采用PCR和毛细管电泳法检测FLT3-ITD,并通过片段分析对其长度和突变频率进行定量评估。但由于该方法存在操作过程易污染,无法识别突变位置和碱基序列,以及突变峰重叠导致FLT3-ITD个数识别出现偏差等不足,从而无法准确定位和量化FLT3-ITD。

二代测序(NGS)技术的蓬勃发展推动了FLT3-ITD检测软件的研发和应用。基于NGS的检测方法能够检测FLT3-ITD的突变位置、碱基序列、插入长度和突变频率等定量信息,有效地克服了传统检测方法的局限性。然而,基于NGS的检测方法仍存在安装部署复杂、检测结果假阳性较高且低估突变频率等问题。因此,突破以上技术瓶颈,开发基于Docker的FLT3-ITD自动化检测框架具有巨大的临床应用价值。


研究设计


本研究纳入了AML队列中的163例患者,使用求臻医学ChosenHeme®对血液样本进行基因检测。此外,基于二代测序数据模拟软件wgsim生成共计500例FLT3-ITD阳性样本。研究首先对现有NGS检测方法的原理、功能和局限性进行了全面研究,然后分别在模拟数据和真实样本上,围绕定性和定量分析能力、结果可读性以及运行时间,对Pindel、ITDseek、ScanITD、ITDetector、getITD和FLT3_ITD_ext六款代表性软件进行性能评估。


求臻医学


图1. 文章结构框架图


研究结果


基于以上对比分析结果,研究者设计了一款基于Docker的FLT3-ITD检测框架,实现了FLT3-ITD的精准检测,并使检测流程趋于自动化、可定制化以及跨平台可移植,为临床医生和科研人员选择合适的FLT3-ITD检测软件提供了有效的指导,同时进一步助力AML的预后分层和个性化诊疗。


未来,求臻医学将使用自主研发的ChosenHeme®血液系统肿瘤基因检测Panel,持续对大规模AML样本集进行测序,积累大量高通量测序数据,深度挖掘AML患者队列中FLT3-ITD的突变特征。与此同时,还将进一步关注靶向FLT3-ITD药物的筛选和研发,推动靶向治疗的发展进程,为更多的AML患者带来福音。


关于FLT3-ITD


FMS样酪氨酸激酶3(FLT3)基因位于染色体13q12.2,其编码的FLT3蛋白属于III型受体酪氨酸激酶(RTK)家族,可以调节细胞凋亡、增殖及造血干/祖细胞的分化,在造血过程中发挥重要作用。


求臻医学


图2. FLT3蛋白结构


FLT3-ITD,即FLT3基因内部串联重复,常见于FLT3基因的14号和15号外显子,其插入长度为3到几百个碱基对不等,多数情况下以3的倍数出现。每个患者中携带FLT3-ITD突变的个数一般为1-3个,且插入位置多覆盖14号外显子的Y591-Y597区域。FLT3-ITD的突变模式,如突变个数、插入长度以及突变频率等,不仅是AML的预后指标,还是AML风险分层的重要考虑因素,对其治疗方案的选择具有一定指导意义。


求臻医学

图3. FLT3-ITD突变特征



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