Tyrosine kinase receptors (TKRs) are a prominent class of receptors that are frequently altered in cancer. These receptors span the cell membrane and, upon binding to their ligands, activate their intracellular kinase domain. This activation phosphorylates tyrosine residues on themselves and other proteins, triggering multiple signaling pathways such as the MAPK/ERK pathway and the PI3K/AKT pathway. Mutations or overexpression of TKRs, such as EGFR or HER2, can result in continuous signaling leading to oncogenesis.
