Background ROS1 fusion-positive (ROS1+) nonsmall cell lung cancer (NSCLC) patients are highly sensitive to tyrosine kinase inhibitor (TKI) treatments. However, acquired TKI resistance remains the major hurdle preventing patients from experiencing prolonged benefits. Methods 107 advanced or metastatic ROS1+ NSCLC patients who progressed on crizotinib and lorlatinib were recruited. Tissue and plasma samples were collected at baseline (N = 50), postcrizotinib (N = 91), and postlorlatinib (N = 21), which were all subject to the 139-gene targeted next-generation DNA sequencing. Molecular dynamics modeling was performed to investigate the effects of ROS1 mutations on binding to different TKIs. Results In patients with postcrizotinib and postlorlatinib samples, an accumulation of on- and off-target resistance alterations after multiple TKI treatments was observed. ROS1 G2032R and MET amplification were the most common on-target and off-target alterations, respectively. Patients with CD74-ROS1 and SLC34A2-ROS1 had longer progression-free survival (PFS) (P < 0.001) and higher rates of resistance mutations (on-target, P = 0.001; off-target, P = 0.077) than other ROS1 fusion variants following crizotinib treatment. Ten distinct on-target resistance mutations were detected after TKI therapies, of which 4 were previously unreported (ROS1 L2010M, G1957A, D1988N, L1982V). Molecular dynamics simulations showed that all 4 mutations were refractory to crizotinib, while G1957A, D1988N, and L1982V were potentially sensitive to lorlatinib and entrectinib. Conclusions This study provided a comprehensive portrait of TKI-resistance mechanisms in ROS1+ NSCLC patients. Using in silico simulations of TKI activity, novel secondary mutations that may confer TKI resistance were identified and may support clinical therapeutic decision-making.

中文翻译：

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ROS1融合阳性非小细胞肺癌对酪氨酸激酶抑制剂的耐药机制

背景 ROS1 融合阳性 (ROS1+) 非小细胞肺癌 (NSCLC) 患者对酪氨酸激酶抑制剂 (TKI) 治疗高度敏感。然而，获得性 TKI 耐药仍然是阻止患者获得长期获益的主要障碍。方法 招募了 107 名接受克唑替尼和劳拉替尼治疗后病情进展的晚期或转移性 ROS1+ NSCLC 患者。在基线（N = 50）、克唑替尼治疗后（N = 91）和劳拉替尼治疗后（N = 21）收集组织和血浆样本，所有这些样本均经过 139 基因靶向下一代 DNA 测序。进行分子动力学建模以研究 ROS1 突变对与不同 TKI 结合的影响。结果在使用克唑替尼后和劳拉替尼后样本的患者中，观察到多次 TKI 治疗后出现的靶点和脱靶耐药性变化的累积。ROS1 G2032R 和 MET 扩增分别是最常见的在靶和脱靶改变。与其他 ROS1 患者相比，CD74-ROS1 和 SLC34A2-ROS1 患者的无进展生存期 (PFS) 更长（P < 0.001），耐药突变率更高（在靶，P = 0.001；脱靶，P = 0.077）克唑替尼治疗后的融合变异。TKI 治疗后检测到 10 种不同的靶向耐药突变，其中 4 种以前未报告（ROS1 L2010M、G1957A、D1988N、L1982V）。分子动力学模拟显示，所有 4 个突变均对克唑替尼耐药，而 G1957A、D1988N 和 L1982V 对 lorlatinib 和 entrectinib 可能敏感。结论 本研究全面描述了 ROS1+ NSCLC 患者的 TKI 耐药机制。使用 TKI 活性的计算机模拟，确定了可能赋予 TKI 耐药性的新型二次突变，并可能支持临床治疗决策。