MUC5AC and neoplasm: Subsequent gene set enrichment analysis (GSEA) of the DEGs in the MUC5AC-high compared with the MUC5AC-low patient groups revealed enrichment of gene signatures associated with epithelial-to-mesenchymal transition (EMT), increased tumor invasiveness, and increased metastasis, suggesting the potential involvement of MUC5AC in LUAD metastasis (Fig. 2i–k).