Table 1_Dynamics of the immune repertoire in recurrent, locally advanced NSCLC not amenable for definitive therapy and in stage IV disease receiving first-line chemotherapy.docx

BackgroundCytotoxic chemotherapy can modulate antitumor immunity, yet its impact on the peripheral T-cell receptor (TCR) repertoire in non-targetable advanced NSCLC remains poorly characterized. We prospectively investigated chemotherapy-induced TCRβ repertoire dynamics and their prognostic relevance.
MethodsPatients with recurrent unresectable locally advanced or stage IV NSCLC without actionable mutations received first-line platinum-based chemotherapy (no immunotherapy) at Ramathibodi Hospital (2021–2024). Peripheral blood was collected at baseline (T1), chemotherapy completion (T2), and confirmed disease progression (T3). TCRβ sequencing (Ion Torrent™ Oncomine™ TCR Beta-LR) was performed on samples rarefied to >1.5 million reads. Shannon diversity, Pielou evenness, TCR convergence frequency, unique clone counts, and principal component analysis (PCA) of clonal frequencies were analyzed. Multiple comparisons were Benjamini–Hochberg corrected (significance: p<0.05, BH-adj. q<0.05).
ResultsOf 42 enrolled patients, 34 were T1-evaluable and 15 at T2; longitudinal attrition was driven primarily by pre-T2 death (74% vs. 27%; p=0.014). Disease control was achieved in 11/15 T2-evaluable patients (73%). Disease control patients trended higher TCR convergence (0.0040 vs. 0.0023) and significantly smaller decline in unique clone counts (−16% vs. −41%; Wilcoxon p=0.020, q=0.030). PCA revealed compact repertoire clustering in disease control versus wide PC2 dispersion in progressive disease (PD) patients (p=0.030, q=0.030). Among 4 patients reaching T3 (all PD), post-chemotherapy rises in Shannon diversity and convergence reversed at T3, consistent with immune attrition. Overall survival was significantly longer in disease control patients (log-rank p=0.036).
ConclusionStable clonal convergence and preserved clone counts associate with disease control and survival in non-targetable advanced NSCLC receiving chemotherapy, supporting peripheral TCRβ profiling as an exploratory biomarker warranting prospective validation.

研究背景：细胞毒性化疗可调控抗肿瘤免疫应答，但目前对于无可靶向驱动突变的晚期非小细胞肺癌（non-targetable advanced NSCLC）患者外周T细胞受体（T-cell receptor, TCR）库的影响仍未得到充分阐明。本研究前瞻性探讨了化疗诱导的TCRβ库动态变化及其预后价值。

研究方法：本研究纳入2021年至2024年在拉玛迪博迪医院（Ramathibodi Hospital）就诊的、无可靶向驱动突变的复发性不可切除局部晚期或IV期非小细胞肺癌患者，所有患者均接受一线铂类化疗且未联合免疫治疗。分别于基线期（T1）、化疗结束时（T2）及确诊疾病进展时（T3）采集外周血样本。采用Ion Torrent™ Oncomine™ TCR Beta-LR试剂盒对经抽平至>150万读长的样本进行TCRβ测序。分析指标包括香农多样性指数（Shannon diversity）、皮卢均匀度（Pielou evenness）、TCR趋同频率、独特克隆计数，以及克隆频率的主成分分析（principal component analysis, PCA）。多重比较采用Benjamini-Hochberg校正（显著性阈值：p<0.05，校正后q<0.05）。

研究结果：本研究共纳入42例入组患者，其中34例可评估T1样本，15例可评估T2样本；纵向随访脱落主要源于T2前死亡（74% vs. 27%；p=0.014）。15例可评估T2样本的患者中，11例达到疾病控制（73%）。疾病控制组患者的TCR趋同频率呈升高趋势（0.0040 vs. 0.0023），且独特克隆计数下降幅度显著更低（-16% vs. -41%；Wilcoxon秩和检验p=0.020，校正后q=0.030）。主成分分析结果显示，疾病控制组患者的TCR库呈现紧密聚类，而进展性疾病（progressive disease, PD）患者的PC2轴分散范围更广（p=0.030，校正后q=0.030）。在4例可获得T3样本的患者（均为PD）中，化疗后出现的香农多样性指数与趋同频率升高在T3时发生逆转，这与免疫耗竭的表现一致。疾病控制组患者的总生存期显著更长（log-rank检验p=0.036）。

研究结论：对于接受化疗的无可靶向驱动突变晚期非小细胞肺癌患者，稳定的克隆趋同状态与保留的克隆计数与疾病控制及总生存期改善显著相关，这提示外周血TCRβ谱可作为潜在的探索性生物标志物，有待开展前瞻性验证研究。