A Lauren-associated mitotic programme in gastric cancer: integrative bulk, single-cell and spatial analyses

Objective: Lauren intestinal- and diffuse-type gastric cancers differ in histological organisation and molecular context, but a reproducible mitotic transcriptional programme linking these subtypes has not been fully resolved. We integrated bulk, single-cell and spatial transcriptomic analyses with network prioritisation and preliminary experimental support to define such a programme while preserving the inferential limits of each data layer. Methods: The discovery cohort was GSE62254 (137 intestinal-type and 129 diffuse-type tumours). Differential expression, gene-set enrichment analysis, covariate-aware weighted gene co-expression network analysis, GO/KEGG enrichment and STRING physical-interaction analysis were followed by three-algorithm centrality prioritisation and 2,000 fixed-seed edge-deletion perturbations. Candidate genes were evaluated across GSE62254, GSE15459 and GSE113255 (total n = 570) by random-effects meta-analysis and sensitivity analyses. GSE183904 was used for patient-aware single-cell localisation, and immune context was estimated with three complementary algorithms. A ten-specimen gastric-cancer cohort provided preliminary RT-qPCR support. Connectivity Map screening, CDC20-pocket docking, exploratory CellChat/NicheNet analysis and donor-level spatial analysis of GSE270678 extended the programme into testable structural and tissue-context hypotheses. Results: The primary and full-clinical differential-expression models identified 5,223 and 3,048 genes, respectively, with 2,978 directionally concordant robust genes. A 449-gene yellow co-expression module yielded 39 candidates after intersection with the robust differential-expression and prespecified mitotic sets. The 39-protein STRING network contained 70 physical edges; centrality convergence identified ten candidates with median perturbation stability of 0.981 versus 0 among non-candidates. Cross-cohort validation froze BIRC5, CDC20, CENPA, CKS1B and NUF2 as the Hub set. The five-gene programme was higher in intestinal-type tumours (pooled Hedges' g = − 0.827, 95% CI − 1.007 to − 0.647; I² = 0%), consistent with RT-qPCR in ten specimens. Single-cell and spatial analyses localised the programme to epithelial and immune compartments and revealed donor-level, context-dependent tissue coupling. Conclusion: BIRC5, CDC20, CENPA, CKS1B and NUF2 define a reproducible Lauren-associated mitotic transcriptional programme with higher bulk activity in intestinal-type gastric cancer. These associative findings provide a prioritised, testable framework for future functional and clinical dissection of Lauren subtype biology.