Spatial association of an AKR1C3-positive epithelial state with ACTA2-positive stromal cells and SPP1-positive macrophages in gastric cancer

Introduction The spatial organization of epithelial states relative to stromal and myeloid cells in gastric cancer remains incompletely understood. Methods We integrated single-cell RNA-sequencing data from 36 normal and tumor tissue samples (GSE183904) with Visium spatial transcriptomics (GSE251950). Cell-state signatures were evaluated in TCGA-STAD (n = 375), and multiplex immunohistochemistry was performed on specimens from three patients. Results Epi4_AKR1C3 and FB3_ACTA2 showed nominal enrichment in tumor tissues, whereas Mac2_SPP1 showed no significant compositional difference between normal and tumor tissues. Higher signature scores for these three states were nominally associated with shorter overall survival (log-rank P = 0.044, 0.019, and 0.048, respectively), although none remained significant after multiple-testing correction. Spatial deconvolution identified regions of co-enrichment, and multiplex immunohistochemistry provided proof-of-concept evidence of close spatial proximity among the corresponding marker-defined populations. Discussion These findings identify a candidate AKR1C3-associated epithelial–stromal–myeloid spatial configuration in gastric cancer. Further mechanistic studies are needed to validate its biological and clinical significance.