Wnt信号通路对癌细胞干细胞（CSCs）的维持至关重要，但β-连环蛋白和APC基因的突变在非小细胞肺癌（NSCLC）中较少见。因此，肺CSCs中Wnt信号通路持续激活的机制仍然未知。我们进行了基因集富集分析和免疫组织化学实验证实了KDM6A/KMT2B与CSC干性的相关性。我们对人类NSCLC细胞系进行了基因修饰的功能研究。我们通过球形成试验和干性基因表达谱分析来研究KDM6A/KMT2B在肺CSCs中的作用。我们使用肿瘤异种移植实验证明了KDM6A/KMT2B在体内对肿瘤发生和复发的功能。我们进行了西方印迹分析、共免疫沉淀和染色质免疫沉淀来了解KDM6A/KMT2B介导的组蛋白H3K4me上Wnt信号通路的表观遗传调控。我们发现组蛋白去甲基化酶KDM6A和甲基转移酶KMT2B的表达与NSCLC的CSCs干性相关。KDM6A与KMT2B协同作用，通过调控H3K4me3水平激活Wnt/β-连环蛋白信号通路，促进CSC干性的肿瘤发生和维持。此外，KDM6A/KMT2B的过表达促进了CSC对化疗的耐药性以及体内外肿瘤复发。抑制KDM6A和KMT2B能够显著抑制异种移植动物模型中肿瘤的发生和复发。我们的研究结果表明，KDM6A和KMT2B介导了肺CSCs中Wnt/β-连环蛋白信号通路的持续激活，可能为NSCLC提供了潜在的治疗靶点。版权所有 © 2023. 由Elsevier Inc.出版。

Wnt signaling is essential for the maintenance of cancer stem cells (CSCs), but mutations in the β-catenin and APC genes are less common in non-small cell lung carcinoma (NSCLC). Thus, the mechanism underlying the constitutive activation of Wnt signaling in lung CSCs is still unknown.Gene set enrichment analysis and immunohistochemistry were performed to establish the correlation between KDM6A/KM2B and CSC stemness. Human NSCLC cell lines were genetically manipulated for functional studies. Sphere formation assay and stemness gene expression profiling were examined to investigate the role of KDM6A/KMT2B in lung CSCs. Tumor xenograft assay were used to identify the function of KDM6A/KMT2B on tumorigenicity and tumor recurrence in vivo. Western blot analysis, coimmunoprecipitation and chromatin immunoprecipitation were performed to understand KDM6A/KMT2B mediated epigenetic regulation of Histone 3 lysine 4 methylation (H3K4me) on Wnt signaling pathway.We discovered that the expression of Histone demethylase KDM6A and methyltransferase KMT2B correlate with the stemness of CSCs in NSCLC. KDM6A coordinates with KMT2B to activate the Wnt/β-catenin signaling pathway by regulating the H3K4me3 level and promotes the tumorigenicity and maintenance of CSC stemness. Furthermore, KDM6A/ KMT2B overexpression promotes the CSC chemoresistance and tumor recurrence both in vitro and in vivo. Inhibition of KDM6A and KMT2B potently suppress tumor initiation and recurrence in xenografted animal models.Our findings suggest that KDM6A and KMT2B mediate the constitutive activation of Wnt/β-catenin signaling in lung CSCs, potentially providing a therapeutic target for NSCLC.Copyright © 2023. Published by Elsevier Inc.