Hummingbird Diagnostics GmbH, Heidelberg, Germany.
Center for Interstitial and Rare Lung Diseases, Department of Pneumology and Critical Care Medicine, Thoraxklinik at Heidelberg University Hospital, Heidelberg, Germany; Translational Lung Research Center Heidelberg (TLRC-H), Member of the German Center for Lung Research (DZL), Heidelberg, Germany.
J Thorac Oncol. 2023 Nov;18(11):1504-1523. doi: 10.1016/j.jtho.2023.07.005. Epub 2023 Jul 16.
Lung cancer remains the deadliest cancer in the world, and lung cancer survival is heavily dependent on tumor stage at the time of detection. Low-dose computed tomography screening can reduce mortality; however, annual screening is limited by low adherence in the United States of America and still not broadly implemented in Europe. As a result, less than 10% of lung cancers are detected through existing programs. Thus, there is a great need for additional screening tests, such as a blood test, that could be deployed in the primary care setting.
We prospectively recruited 1384 individuals meeting the National Lung Screening Trial demographic eligibility criteria for lung cancer and collected stabilized whole blood to enable the pipetting-free collection of material, thus minimizing preanalytical noise. Ultra-deep small RNA sequencing (20 million reads per sample) was performed with the addition of a method to remove highly abundant erythroid RNAs, and thus open bandwidth for the detection of less abundant species originating from the plasma or the immune cellular compartment. We used 100 random data splits to train and evaluate an ensemble of logistic regression classifiers using small RNA expression of 943 individuals, discovered an 18-small RNA feature consensus signature (miLung), and validated this signature in an independent cohort (441 individuals). Blood cell sorting and tumor tissue sequencing were performed to deconvolve small RNAs into their source of origin.
We generated diagnostic models and report a median receiver-operating characteristic area under the curve of 0.86 (95% confidence interval [CI]: 0.84-0.86) in the discovery cohort and generalized performance of 0.83 in the validation cohort. Diagnostic performance increased in a stage-dependent manner ranging from 0.73 (95% CI: 0.71-0.76) for stage I to 0.90 (95% CI: 0.89-0.90) for stage IV in the discovery cohort and from 0.76 to 0.86 in the validation cohort. We identified a tumor-shed, plasma-bound ribosomal RNA fragment of the L1 stalk as a dominant predictor of lung cancer. The fragment is decreased after surgery with curative intent. In additional experiments, results of dried blood spot collection and sequencing revealed that small RNA analysis could potentially be conducted through home sampling.
These data suggest the potential of a small RNA-based blood test as a viable alternative to low-dose computed tomography screening for early detection of smoking-associated lung cancer.
肺癌仍然是全球最致命的癌症，肺癌的存活率在很大程度上取决于检测时的肿瘤分期。低剂量计算机断层扫描筛查可以降低死亡率；然而，由于美国的参与度低，年度筛查受到限制，且尚未在欧洲广泛实施。因此，目前的筛查方案中不到 10%的肺癌被发现。因此，非常需要额外的筛查测试，例如血液测试，可以在初级保健环境中部署。
我们前瞻性地招募了符合国家肺癌筛查试验人口统计学入选标准的 1384 名肺癌患者，并采集了稳定的全血，以便进行无需移液的标本采集，从而最大程度地减少了分析前的噪音。对每个样本进行了超深度小 RNA 测序（每个样本 2000 万条读长），并添加了一种去除高丰度红细胞 RNA 的方法，从而为检测来自血浆或免疫细胞区室的低丰度物质开放了带宽。我们使用 100 个随机数据拆分，通过对 943 名个体的小 RNA 表达进行训练和评估逻辑回归分类器的集合，发现了一个由 18 个小 RNA 特征组成的共识特征签名（miLung），并在一个独立的队列（441 名个体）中进行了验证。进行血液细胞分选和肿瘤组织测序以将小 RNA 解析为其来源。
我们生成了诊断模型，并在发现队列中报告了中位数接收者操作特征曲线下面积为 0.86（95%置信区间 [CI]：0.84-0.86），在验证队列中的广义性能为 0.83。诊断性能呈阶段依赖性增加，范围从发现队列中 I 期的 0.73（95%CI：0.71-0.76）到 IV 期的 0.90（95%CI：0.89-0.90），以及验证队列中从 0.76 到 0.86。我们发现了一种肿瘤脱落的、血浆结合的核糖体 RNA 片段 L1 茎，它是肺癌的主要预测因子。该片段在有治愈意图的手术后减少。在额外的实验中，干血斑采集和测序的结果表明，小 RNA 分析可能通过家庭采样进行。
这些数据表明，基于小 RNA 的血液测试作为低剂量计算机断层扫描筛查的替代方法，用于早期发现与吸烟相关的肺癌具有潜在的可能性。
