Single-Cell Mapping Reveals MIF-Centered Immunoregulatory Networks in Colorectal Cancer

Colorectal cancer (CRC) progression is strongly shaped by the tumor microenvironment (TME), where complex interactions between epithelial, immune, and stromal cells orchestrate immune suppression and tumor evolution. To dissect these relationships at single-cell resolution, we analyzed CRC scRNA-seq datasets using Seurat for data integration and CellChat for ligand-receptor inference. We identified extensive cellular heterogeneity within the TME, dominated by CMS2/CMS3 epithelial states, SPP1⁺ tumor-associated macrophages, diverse T-cell subsets, and CXCR4⁺ B cells. Communication analysis revealed MIF-centered signaling-including MIF-CD74-CXCR4 and MIF-CD74-CD44-as the predominant axis linking tumor epithelial cells with T cells, B cells, and macrophage subpopulations. CMS3 epithelial cells displayed particularly strong connectivity to SPP1⁺ macrophages and cytotoxic lymphocytes through both MIF- and APP-CD74-mediated pathways. Differential gene expression confirmed elevated levels of MIF, CD74, CD44, and SPP1 in tumor tissues, while pathway enrichment analyses highlighted cytokine signaling, antigen presentation, and chemokine-regulated immune modulation as key biological processes. Collectively, our study provides a high-resolution map of CRC intercellular communication and identifies MIF-CD74-associated signaling as a central immunoregulatory hub with potential relevance for therapeutic targeting and biomarker development.