Panitumumab works by specifically binding to the extracellular domain of EGFR, a transmembrane glycoprotein involved in the regulation of cell growth, apoptosis, and differentiation. When EGFR is overexpressed or mutated, it can lead to uncontrolled cell division and tumor growth. Panitumumab blocks the binding of endogenous ligands such as EGF and TGF-α, thereby preventing receptor dimerization and autophosphorylation, which are essential for the activation of downstream signaling pathways like the RAS-RAF-MEK-ERK and PI3K-AKT pathways.
