PDF(Pubmed)
Abstract：
ALK, ROS1, and RET fusions and MET∆ex14 variant associate with response to targeted therapies in non-small-cell lung cancer (NSCLC). Technologies for fusion testing in tissue must be adapted to liquid biopsies, which are often the only material available. In this study, circulating-free RNA (cfRNA) and extracellular vesicle RNA (EV-RNA) were purified from liquid biopsies. Fusion and MET∆ex14 transcripts were analyzed by nCounter (Nanostring) and digital PCR (dPCR) using the QuantStudio® System (Applied Biosystems). We found that nCounter detected ALK, ROS1, RET, or MET∆ex14 aberrant transcripts in 28/40 cfRNA samples from positive patients and 0/16 of control individuals (70% sensitivity). Regarding dPCR, aberrant transcripts were detected in the cfRNA of 25/40 positive patients. Concordance between the two techniques was 58%. Inferior results were obtained when analyzing EV-RNA, where nCounter often failed due to a low amount of input RNA. Finally, results of dPCR testing in serial liquid biopsies of five patients correlated with response to targeted therapy. We conclude that nCounter can be used for multiplex detection of fusion and MET∆ex14 transcripts in liquid biopsies, showing a performance comparable with next-generation sequencing platforms. dPCR could be employed for disease follow-up in patients with a known alteration. cfRNA should be preferred over EV-RNA for these analyses.
摘要：
ALK,在非小细胞肺癌（NSCLC）中，ROS1和RET融合以及MET÷ex14变体与非小细胞肺癌（NSCLC）靶向治疗的反应相关。组织融合检测技术必须适应液体活检，通常是唯一可用的材料。在这项研究中,从液体活检中纯化无循环RNA(cfRNA)和细胞外囊泡RNA(EV-RNA)。使用QuantStudio®系统（应用生物系统）通过nCounter（Nanostring）和数字PCR（dPCR）分析融合和METΔex14转录本。我们发现nCounter检测到ALK,来自阳性患者和对照个体的0/16的28/40cfRNA样品中的ROS1，RET或METΔex14异常转录本（70％敏感性）。关于dPCR，在25/40阳性患者的cfRNA中检测到异常转录本。两种技术的一致性为58%。分析EV-RNA时获得了较差的结果，其中nCounter通常由于输入RNA量低而失败。最后,5例患者连续液体活检的dPCR检测结果与靶向治疗反应相关.我们得出的结论是，nCounter可用于液体活检中融合和METΔex14转录本的多重检测，显示与下一代测序平台相当的性能。dPCR可用于已知改变的患者的疾病随访。对于这些分析，cfRNA应优于EV-RNA。
