Objective The optimal therapeutic response in cancer patients is highly dependent upon the differentiation state of their tumours. Pancreatic ductal adenocarcinoma (PDA) is a lethal cancer that harbours distinct phenotypic subtypes with preferential sensitivities to standard therapies. This study aimed to investigate intratumour heterogeneity and plasticity of cancer cell states in PDA in order to reveal cell state-specific regulators. Design We analysed single-cell expression profiling of mouse PDAs, revealing intratumour heterogeneity and cell plasticity and identified pathways activated in the different cell states. We performed comparative analysis of murine and human expression states and confirmed their phenotypic diversity in specimens by immunolabeling. We assessed the function of phenotypic regulators using mouse models of PDA, organoids, cell lines and orthotopically grafted tumour models. Results Our expression analysis and immunolabeling analysis show that a mucus production programme regulated by the transcription factor SPDEF is highly active in precancerous lesions and the classical subtype of PDA — the most common differentiation state. SPDEF maintains the classical differentiation and supports PDA transformation in vivo . The SPDEF tumour-promoting function is mediated by its target genes AGR2 and ERN2 /IRE1β that regulate mucus production, and inactivation of the SPDEF programme impairs tumour growth and facilitates subtype interconversion from classical towards basal-like differentiation. Conclusions Our findings expand our understanding of the transcriptional programmes active in precancerous lesions and PDAs of classical differentiation, determine the regulators of mucus production as specific vulnerabilities in these cell states and reveal phenotype switching as a response mechanism to inactivation of differentiation states determinants. Data are available in a public, open access repository. The full list can be found in online supplemental materials and methods. Further information and requests for resources and reagents should be directed to the lead contact, Dr. David A. Tuveson dtuveson@cshl.edu.

中文翻译：

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粘液产生程序促进经典胰腺导管腺癌

目的 癌症患者的最佳治疗反应高度依赖于肿瘤的分化状态。胰腺导管腺癌 (PDA) 是一种致命的癌症，具有不同的表型亚型，对标准治疗具有优先敏感性。本研究旨在研究 PDA 中癌细胞状态的肿瘤内异质性和可塑性，以揭示细胞状态特异性调节因子。设计 我们分析了小鼠 PDA 的单细胞表达谱，揭示了肿瘤内异质性和细胞可塑性，并确定了在不同细胞状态下激活的途径。我们对小鼠和人类的表达状态进行了比较分析，并通过免疫标记证实了它们在标本中的表型多样性。我们使用 PDA、类器官、细胞系和原位移植肿瘤模型的小鼠模型评估了表型调节因子的功能。结果我们的表达分析和免疫标记分析表明，由转录因子 SPDEF 调节的粘液产生程序在癌前病变和 PDA 的经典亚型（最常见的分化状态）中高度活跃。 SPDEF 保持经典分化并支持 PDA 体内转化。 SPDEF 促肿瘤功能由其调节粘液产生的靶基因 AGR2 和 ERN2 /IRE1β 介导，SPDEF 程序的失活会损害肿瘤生长并促进亚型从经典分化向基底样分化的相互转化。结论 我们的研究结果扩展了我们对癌前病变和经典分化的 PDA 中活跃的转录程序的理解，确定了粘液产生的调节因子是这些细胞状态中的特定脆弱性，并揭示了表型转换是对分化状态决定因素失活的反应机制。数据可在公共、开放访问存储库中获取。完整列表可以在在线补充材料和方法中找到。如需了解更多信息以及对资源和试剂的请求，请直接联系主要联系人 David A. Tuveson 博士 dtuveson@cshl.edu。