Single-Cell Transcriptomic Characterization of the Tumor Microenvironment in Prostate Cancer Bone Metastases

BACKGROUND: Prostate cancer (PCa) bone metastases cause significant morbidity and mortality in advanced disease. The tumor microenvironment (TME) of bone metastases drives disease progression and therapeutic resistance, yet comprehensive characterization of its cellular heterogeneity remains limited. This study aims to characterize cellular populations and molecular signatures of PCa bone metastases using single-cell RNA sequencing (scRNA-seq) data from the Gene Expression Omnibus (GEO) database. METHODS: scRNA-seq data from PCa bone metastasis samples were obtained from GEO. Quality control, normalization, dimensionality reduction, and cell type identification were performed using Seurat. Differential expression, pseudotime trajectory, pathway enrichment, gene regulatory network, and cell-cell communication analyses were conducted to investigate molecular mechanisms of bone metastasis progression. RESULTS: Single-cell analysis identified distinct cellular populations within the bone metastatic TME, including malignant epithelial cells, fibroblasts, endothelial cells, osteoblasts, osteoclasts, and immune cells. Clustering revealed heterogeneous transcriptional signatures, while pseudotime analysis uncovered developmental transitions between cell states. Key transcription factors, enriched pathways related to bone remodeling, angiogenesis, and immune regulation, and critical signaling interactions between cancer and stromal cells were identified. CONCLUSION: This study provides comprehensive insights into the cellular composition and molecular architecture of the PCa bone metastatic TME, revealing distinct cell populations, type-specific gene signatures, and cell-cell communication networks driving bone metastasis progression.