1. Smoking-induced CCNA2 expression promotes lung adenocarcinoma tumorigenesis by boosting AT2/AT2-like cell differentiation.
- Author
-
He Q, Qu M, Xu C, Wu L, Xu Y, Su J, Bao H, Shen T, He Y, Cai J, Xu D, Zeng LH, and Wu X
- Subjects
- Animals, Female, Humans, Male, Mice, Alveolar Epithelial Cells metabolism, Alveolar Epithelial Cells pathology, beta Catenin metabolism, beta Catenin genetics, Cell Line, Tumor, Cyclin-Dependent Kinase 2 genetics, Cyclin-Dependent Kinase 2 metabolism, Gene Expression Regulation, Neoplastic, Neoplastic Stem Cells pathology, Neoplastic Stem Cells metabolism, Wnt Signaling Pathway genetics, Rats, Adenocarcinoma of Lung genetics, Adenocarcinoma of Lung pathology, Adenocarcinoma of Lung metabolism, Carcinogenesis genetics, Cell Differentiation, Cyclin A2 genetics, Cyclin A2 metabolism, Lung Neoplasms pathology, Lung Neoplasms genetics, Lung Neoplasms metabolism, Smoking adverse effects
- Abstract
Lung adenocarcinoma (LUAD), a type of non-small cell lung cancer (NSCLC), originates from not only bronchial epithelial cells but also alveolar type 2 (AT2) cells, which could differentiate into AT2-like cells. AT2-like cells function as cancer stem cells (CSCs) of LUAD tumorigenesis to give rise to adenocarcinoma. However, the mechanism underlying AT2 cell differentiation into AT2-like cells in LUAD remains unknown. We analyze genes differentially expressed and genes with significantly different survival curves in LUAD, and the combination of these two analyses yields 147 differential genes, in which 14 differentially expressed genes were enriched in cell cycle pathway. We next analyze the protein levels of these genes in LUAD and find that Cyclin-A2 (CCNA2) is closely associated with LUAD tumorigenesis. Unexpectedly, high CCNA2 expression in LUAD is restrictedly associated with smoking and independent of other driver mutations. Single-cell sequencing analyses reveal that CCNA2 is predominantly involved in AT2-like cell differentiation, while inhibition of CCNA2 significantly reverses smoking-induced AT2-like cell differentiation. Mechanistically, CCNA2 binding to CDK2 phosphorylates the AXIN1 complex, which in turn induces ubiquitination-dependent degradation of β-catenin and inhibits the WNT signaling pathway, thereby failing AT2 cell maintenance. These results uncover smoking-induced CCNA2 overexpression and subsequent WNT/β-catenin signaling inactivation as a hitherto uncharacterized mechanism controlling AT2 cell differentiation and LUAD tumorigenesis., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)
- Published
- 2024
- Full Text
- View/download PDF