Research Institute for Diseases of the Chest, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
Department of Genome Biology, Faculty of Medicine, Kindai University, Osaka, Japan.
Oncologist. 2019 Aug;24(8):1022-1026. doi: 10.1634/theoncologist.2019-0101. Epub 2019 Apr 25.
Patients with non-small cell lung cancer (NSCLC) treated with epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) eventually acquire resistance to these drugs. The identification of various resistance mechanisms for determination of subsequent treatment for these patients will require a method for simultaneous detection of multiple genetic alterations with high sensitivity. We performed cancer personalized profiling by deep sequencing (CAPP-Seq) with circulating tumor DNA obtained from patients with NSCLC who acquired resistance to first- or second-generation EGFR-TKIs. Plasma samples from 27 patients were analyzed, and 24 samples underwent CAPP-Seq successfully. Original activating mutations were detected in 23 patients, with the remaining patient showing amplification. With regard to known mechanisms of EGFR-TKI resistance, the T790M mutation of was detected in 17 of the 24 patients, amplification in 9 patients (6 of whom also harbored T790M), amplification in 2 patients (1 of whom also harbored T790M), and amplification in 4 patients (all of whom harbored T790M). Our results thus show that CAPP-Seq is applicable to clinical samples for the identification of multiple somatic mutations in circulating tumor DNA obtained from patients with NSCLC at the time of disease progression during treatment with first- or second-generation EGFR-TKIs. Patients positive for the T790M mutation of were also found to constitute a molecularly heterogeneous population. KEY POINTS: CAPP-Seq is applicable to clinical samples for the identification of multiple somatic mutations.The T790M mutation of is associated with amplification of , , or in NSCLC patients resistant to EGFR-TKIs.T790M-positive patients are molecularly heterogeneous, and genetic alterations coexisting with T790M may differ between patients treated with first-generation or second-generation EGFR-TKIs.
接受表皮生长因子受体（EGFR）酪氨酸激酶抑制剂（TKI）治疗的非小细胞肺癌（NSCLC）患者最终会对这些药物产生耐药性。为了确定这些患者的后续治疗方法，需要一种能够同时高灵敏度检测多种遗传改变的方法。我们使用从对第一代或第二代 EGFR-TKI 产生耐药的 NSCLC 患者中获得的循环肿瘤 DNA 进行癌症个体化基因谱测序（CAPP-Seq）。分析了 27 名患者的血浆样本，其中 24 个样本成功进行了 CAPP-Seq。在 23 名患者中检测到原始激活突变，1 名患者显示扩增。对于 EGFR-TKI 耐药的已知机制，在 24 名患者中的 17 名中检测到 突变，9 名患者中扩增（其中 6 名患者也存在 T790M），2 名患者中扩增（其中 1 名患者也存在 T790M），4 名患者中扩增（所有患者均存在 T790M）。因此，我们的研究结果表明，CAPP-Seq 可适用于临床样本，用于鉴定在第一代或第二代 EGFR-TKI 治疗期间疾病进展时从 NSCLC 患者的循环肿瘤 DNA 中获得的多种体细胞突变。还发现， 突变阳性的患者构成了一个分子异质性人群。关键点：CAPP-Seq 可适用于临床样本，用于鉴定在第一代或第二代 EGFR-TKI 治疗期间疾病进展时从 NSCLC 患者的循环肿瘤 DNA 中获得的多种体细胞突变。在对 EGFR-TKI 耐药的 NSCLC 患者中， 突变与 、 或 的扩增有关。T790M 阳性患者存在分子异质性，并且与 T790M 共存的遗传改变在接受第一代或第二代 EGFR-TKI 治疗的患者之间可能不同。
