Integrated single-cell and spatial transcriptomics reveals a multicellular program contributing to immunotherapy...

Advanced renal cell carcinoma frequently acquires resistance to immune checkpoint blockade (ICB), underscoring the pivotal influence of the tumor immune microenvironment (TME) on therapeutic efficacy. While recent studies have implicated multicellular crosstalk within the TME as a central driver of ICB resistance, the precise multicellular programs (MCPs) that orchestrate this process remain poorly defined. Here, through integrative single-cell and spatial transcriptomic profiling of clear cell RCC (ccRCC) cohorts, we delineated a previously unrecognized MCP associated with ICB resistance, distinguished by heightened lysosomal activity, adipogenic signaling, and rewired fatty acid metabolism. Within this program, we uncover a coordinated interplay among TAM_APOE, ccRCC_CXCL14, and endothelial cells, whereby ccRCC_CXCL14 recruits TAM_APOE, which subsequently promotes tumor lipid metabolic reprogramming and angiogenesis, forming a pro-tumorigenic feedforward loop. Spatial mapping revealed a malignant gene topic colocalizing with this MCP in tumor cores, which robustly predicted both unfavorable survival and resistance in ICB-treated patients. Functional assays confirmed that the CXCL14-TAM axis promotes metabolic reprogramming, while dual CXCR4 and PD-1 blockade synergistically reverses the resistant phenotype by restoring CD8⁺ T-cell cytotoxicity. Multiplex immunofluorescence further validated the enrichment of this MCP specifically in non-responders. Collectively, our study defines a spatially organized, functionally coordinated multicellular niche that drives ICB resistance in ccRCC, establishing both a predictive biomarker for patient stratification and a mechanistic framework for therapeutic intervention.