AG 1478 hydrochloride is widely used in biomedical research as a selective inhibitor of the epidermal growth factor receptor (EGFR) tyrosine kinase. It is commonly applied in studies involving cell signaling pathways related to cell proliferation, survival, and differentiation. Due to its ability to block EGFR autophosphorylation, it is used to investigate the role of EGFR in cancer development, particularly in models of lung, breast, and head and neck cancers. Researchers also utilize AG 1478 hydrochloride to suppress aberrant EGFR activity in vitro and in vivo, helping to evaluate potential therapeutic strategies. Additionally, it has been employed in studies exploring wound healing, angiogenesis, and neuronal protection, where EGFR signaling plays a regulatory role. Its specificity makes it a valuable tool for dissecting kinase-dependent cellular mechanisms.