Integrated transcriptomic and functional characterization of Claudin-1 reveals its oncogenic and immunomodulatory roles in pancreatic ductal adenocarcinoma.
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引用次数: 0
Abstract
Pancreatic ductal adenocarcinoma (PDAC) remains among the deadliest malignancies, driven by its invasive nature and lack of effective biomarkers. Disruption of the epithelial barrier, mediated by tight junction components, is a critical yet underexplored contributor to PDAC progression. Claudins, integral regulators of tight junction integrity, display altered expression across cancers, but their prognostic and immunomodulatory roles in PDAC remain unclear. We performed an integrative analysis of 177 RNA-Seq datasets from TCGA and GTEx to characterize Claudin family alterations in PDAC. Differential expression, copy number variation, methylation, and co-expression networks were analyzed alongside clinical and survival data. Prognostic significance was assessed using Kaplan - Meier and Cox regression analyses, while immune cell infiltration was examined using deconvolution algorithms. Functional validation of Claudin-1 was conducted in Capan-1 cells using CRISPR/Cas9 knockout, followed by proliferation, wound-healing, and Western blot assays. Ten Claudin genes were significantly dysregulated, with Claudin-1 and Claudin-4 frequently amplified and associated with advanced stage and poor survival. High Claudin-1 expression correlated with reduced immune infiltration, indicating an immune-excluded phenotype characterized by immune cells retained in the tumor stroma but largely absent from the tumor parenchyma. Claudin-1 knockout markedly inhibited proliferation, migration, and EMT, evidenced by downregulation of Snail and Slug and restoration of E-cadherin expression. This integrative transcriptomic and functional study identifies Claudin-1 as a key driver of PDAC aggressiveness and immune modulation. These findings establish Claudin-1 as a promising prognostic biomarker and therapeutic target for restoring epithelial integrity and counteracting immune evasion in pancreatic cancer.
期刊介绍:
Tissue Barriers is the first international interdisciplinary journal that focuses on the architecture, biological roles and regulation of tissue barriers and intercellular junctions. We publish high quality peer-reviewed articles that cover a wide range of topics including structure and functions of the diverse and complex tissue barriers that occur across tissue and cell types, including the molecular composition and dynamics of polarized cell junctions and cell-cell interactions during normal homeostasis, injury and disease state. Tissue barrier formation in regenerative medicine and restoration of tissue and organ function is also of interest. Tissue Barriers publishes several categories of articles including: Original Research Papers, Short Communications, Technical Papers, Reviews, Perspectives and Commentaries, Hypothesis and Meeting Reports. Reviews and Perspectives/Commentaries will typically be invited. We also anticipate to publish special issues that are devoted to rapidly developing or controversial areas of research. Suggestions for topics are welcome. Tissue Barriers objectives: Promote interdisciplinary awareness and collaboration between researchers working with epithelial, epidermal and endothelial barriers and to build a broad and cohesive worldwide community of scientists interesting in this exciting field. Comprehend the enormous complexity of tissue barriers and map cross-talks and interactions between their different cellular and non-cellular components. Highlight the roles of tissue barrier dysfunctions in human diseases. Promote understanding and strategies for restoration of tissue barrier formation and function in regenerative medicine. Accelerate a search for pharmacological enhancers of tissue barriers as potential therapeutic agents. Understand and optimize drug delivery across epithelial and endothelial barriers.