In both BAS1 and BAS2, cluster 9 exhibits over-expression of basal cell markers (KRT5, KRT14, and KRT17)65, and SERPINA366, and genes associated with extracellular matrix remolding, collagen metabolism, cell migration, tissue repair, inflammatory response, and the PI3K-Akt signaling pathway, underscoring its critical role in promoting tumor cell invasion (Fig. 6h–j). Here, KRT5 is linked to neoplasm.