Abstract
OBJECTIVE: This study examines the cellular heterogeneity of epithelial cells within pancreatic ductal adenocarcinoma (PDAC) and their contributions to tumor progression, metastasis, and immunosuppressive interactions using single-cell RNA sequencing. METHODS: Single-cell RNA-sequencing data from two datasets (GSE154778 and GSE158356) were integrated using the Harmony algorithm, followed by quality control, clustering, and differential gene expression analysis. Distinct subpopulations of epithelial cells were identified, and their gene expression profiles were analyzed. To assess the malignancy of these subpopulations, single-cell copy number variation (CNV) analysis and trajectory analysis were conducted. Additionally, intercellular communication was examined using the CellChat platform. RESULTS: The analysis revealed pronounced heterogeneity among PDAC epithelial cells, with specific subpopulations exhibiting distinct roles in tumor proliferation, extracellular matrix remodeling, and metastatic dissemination. Subpopulations 4 and 6 were characterized by increased CNV levels and a more malignant phenotype, suggesting an enhanced capacity for metastasis. Single-cell trajectory analysis, along with CellChat, mapped the temporal evolution of epithelial cells, identifying key regulatory genes such as DCBLD2 and JUN. A prognostic model incorporating five key genes, including KLF6, was developed and demonstrated strong predictive accuracy for patient outcomes. Notably, KLF6 emerged as a critical prognostic marker associated with immune modulation, particularly through interactions with M2 macrophages. CONCLUSION: The study highlights the pronounced heterogeneity of epithelial cells in PDAC and their distinct contributions to tumor progression, metastasis, and immune modulation. Through single-cell transcriptomic and CNV analyses, we identified epithelial subpopulations with varying malignant potentials and distinct interactions with the tumor microenvironment. Among these, KLF6 emerged as a key regulator associated with immune modulation and metastasis. Our findings emphasize the significance of epithelial cell heterogeneity in shaping pancreatic cancer progression. These insights provide a foundation for future investigations into novel prognostic markers and therapeutic strategies.