ITGA6 and head and neck squamous cell carcinoma: All components of this receptor-ligand complex, i.e. ITGA6, ITGB4, LAMA3, LAMB3, and LAMC2, were up-regulated in HNSCC mRNA expression data (Supplementary Figs. 4– 8), and significantly correlated to ITGB4 in bulk tumor and in malignant single cells mRNA expression data (Supplementary Fig. 3).