PO.PR02.03 · 预防研究
空气污染物将突变上皮重塑为趋同的肺腺癌祖细胞状态
Air pollutants remodel mutant epithelia toward a convergent lung adenocarcinoma progenitor state
作者与单位 Authors & Affiliations
摘要 Abstract
中文摘要
肺上皮含有祖细胞群，包括基底细胞、棒状（club）细胞、神经内分泌细胞以及I/II型肺泡细胞（AT1/AT2）。一种高度可塑的Krt8+肺泡中间细胞状态（KAC）出现在Kras驱动的肿瘤发生和肺损伤模型中。环境颗粒物（PM）暴露通过巨噬细胞来源的白细胞介素-1β（IL-1β）促进肺肿瘤发生。EGFR突变（EGFRm）是从不吸烟者肺癌最常见的基因组驱动因素，其与肿瘤促进如何在单细胞水平上从多种肺上皮谱系驱动肺腺癌（LUAD）仍不明确。理解这一点将有助于开发分子靶向预防策略，尤其是针对从不吸烟者。
我们构建了在基底细胞、棒状细胞、神经内分泌细胞和AT2谱系中谱系特异性激活EGFR-L858R的小鼠模型。利用组织学和snRNA-seq对来自100只小鼠的37,627个细胞评估LUAD的发生和谱系趋同。对于PM效应，通过Ad5-Spc-Cre气管内滴注在AT2细胞中诱导EGFR-L858R，随后进行PM或PBS暴露。采用10X multiome snRNA-seq（34,459个AT2谱系细胞）和snATAC-seq分析转录和表观遗传变化。将EGFRm精密切割肺切片（PCLS）在IgG或抗IL-1β阻断抗体存在下进行体外PM暴露。
我们的分析显示，LUAD起源于基底细胞、棒状细胞、神经内分泌细胞和AT2谱系——它们全部趋同于一种肺泡样状态，与KRAS驱动的LUAD中观察到的轨迹一致。值得注意的是，在源自基底细胞、棒状细胞和AT2谱系的EGFRm细胞中均检测到肺泡KAC，表明早期肿瘤发生过程中存在一种保守的过渡状态。EGFRm激活还诱导了KAC特征基因，同时保留谱系特异性标志物，反映了谱系趋同与记忆的双重程序。在PM暴露后，EGFRm KAC表现出应激反应性和炎症诱导性上皮基因的显著上调。与野生型AT2对照相比，PM暴露的EGFRm KAC表现出LUAD相关转录本的强烈富集，重叠度超过30%，涵盖1,298个基因。这凸显了EGFRm与环境诱导损伤之间的协同作用。此外，我们发现KAC的表观遗传重连，其特征是PM暴露后与IL-1β通路相关的转录因子被激活。在功能上，在PCLS中阻断IL-1β能有效抑制KAC形成，从而建立了炎症信号与早期肿瘤细胞命运之间的机制联系。
总之，我们表明上皮谱系在通往EGFR驱动LUAD的过程中趋同于KAC，而KAC在PM暴露后发生扩增并经历转录和表观遗传重塑。未来阐明KAC扩增及其IL-1β依赖性关键调控因子的研究，可能为分子癌症预防提供新的治疗途径。
查看英文原文 English abstract
The lung epithelium harbours progenitor populations, including basal, club, neuroendocrine, and alveolar type I/II (AT1/AT2) cells. A highly plastic Krt8+ alveolar intermediate cell state (KAC) arises in Kras -driven tumorigenesis and in lung injury models. Environmental particulate matter (PM) exposure promotes lung tumorigenesis through macrophage-derived interleukin-1beta (IL-1beta). How EGFR mutations (EGFRm), the most common genomic driver of lung cancer in never-smokers, and tumour promotion drive lung adenocarcinoma (LUAD) at the single cell level from diverse lung epithelial lineages remains unclear. Understanding this will aid development of molecularly targeted prevention approaches, particularly in never-smokers.
We generated mouse models of lineage-specific activation of EGFR-L858R within basal, club, neuroendocrine, and AT2 lineages. LUAD development and lineage convergence were assessed using histology and snRNA-seq across 37,627 cells from 100 mice. For PM effects, EGFR-L858R induction in AT2 cells was achieved via Ad5-Spc-Cre intratracheal instillation, followed by PM or PBS exposure. 10X multiome snRNA-seq (34,459 AT2-lineage cells) and snATAC-seq were used to profile transcriptional and epigenetic changes. EGFRm precision-cut lung slices (PCLS) were exposed to PM ex vivo in presence of IgG or anti- IL-1beta blocking antibodies.
Our analysis revealed that LUAD arises from basal, club, neuroendocrine, and AT2 lineages - all converging on an alveolar-like state, mirroring the trajectory observed in KRAS-driven LUAD. Notably, alveolar KACs were detected in EGFRm cells derived from basal, club, and AT2 lineages, indicating a conserved transitional state during early tumorigenesis. EGFRm activation also induced KAC-signature genes while preserving lineage-specific markers, reflecting a dual programme of lineage convergence and memory. Upon PM exposure, EGFRm KACs exhibited pronounced upregulation of stress-responsive and inflammation-induced epithelial genes. Compared with wild-type AT2 controls, PM-exposed EGFRm KACs exhibited strong enrichment of LUAD-associated transcripts, with over 30% overlap encompassing 1,298 genes. This highlights the synergy between EGFRm and environment-induced injury. Furthermore, we identified epigenetic rewiring of KACs, marked by activation of transcription factors linked to the IL-1beta pathway upon PM. Functionally, blocking IL-1beta in PCLS effectively inhibited KAC formation, establishing a mechanistic link between inflammatory signalling and early tumour cell fate.
In conclusion, we showed that epithelial lineages converge on KACs en-route to EGFR -driven LUAD, which expands and undergoes transcriptional and epigenetic remodelling upon PM-exposure. Future studies defining key regulators of KAC expansion and its IL-1beta dependency could inform novel therapeutic avenues for molecular cancer prevention.
利益披露 Disclosure
M. M. Leung, None.
M. Zagorulya,
Baseimmune Ltd Employment, M.Z. is employed by Baseimmune Ltd and owns shares in the company; this employment is unrelated to the present study.
T. Pandya,
FutureHouse Independent Contractor, T.P. has undertaken consultancy work for FutureHouse, a not-for-profit AI startup, although unrelated to the scope of this project.
M. Augustine,
FutureHouse Independent Contractor, M.A. has undertaken consultancy work for FutureHouse, a not-for-profit AI startup, although unrelated to the scope of this project.
A. J. Griffen, None..
A. Le Marois, None..
S. Ward, None..
H. Slawinski, None..
A. Suárez-Bonnet, None..
S. L. Priestnall, None..
A. Hardas, None..
L. M. LaFave, None..
E. Gronroos, None..
N. McGranahan, None..
C. Weeden, None.
C. Swanton,
AstraZeneca ), He is Chief Investigator for the AstraZeneca MeRmaiD 1 and 2 clinical trials and is the Steering Committee Chair..
Boehringer-Ingelheim ).
Bristol Myers Squibb ).
Pfizer ).
Roche-Ventana ).
Invitae ).
Ono Pharmaceutical ).
Personalis ).
GRAIL Stock Option, ), He is Co-Chief Investigator of the NHS Galleri trial funded by GRAIL and a paid member of GRAIL’s Scientific Advisory Board (SAB)..
Bicycle Therapeutics Independent Contractor, Stock Option.
Genentech Independent Contractor.
Medicxi Independent Contractor.
China Innovation Centre of Roche Independent Contractor.
Relay Therapeutics Independent Contractor, Stock Option.
Saga Diagnostics Independent Contractor.
Sarah Cannon Research Institute Independent Contractor.
Epic Bioscience Stock Option.