Anaplastic lymphoma kinase (ALK) fusion protein (ALK fusion protein)

Anaplastic lymphoma kinase (ALK) fusion proteins are chimeric oncoproteins generated by chromosomal translocations that fuse the intracellular kinase domain of the ALK gene with various amino-terminal partner proteins, most commonly EML4 in lung cancer and NPM1 in lymphoma (National Cancer Institute, 2023). These fusions result in the constitutive, ligand-independent dimerization and activation of the ALK tyrosine kinase, which normally functions as a cell surface receptor during neural development (UniProt, 2024). The persistent kinase activity drives oncogenic signaling through the PI3K/AKT, RAS/MAPK, and JAK/STAT pathways, leading to enhanced cell survival and proliferation (StatPearls, 2023). ALK rearrangements are critical biomarkers in approximately 3-5% of non-small cell lung cancer (NSCLC) cases and are also found in anaplastic large cell lymphoma and inflammatory myofibroblastic tumors (PubMed, 2022). Pharmacological targeting of these proteins involves ALK-specific tyrosine kinase inhibitors (TKIs) like crizotinib, alectinib, and lorlatinib, which block the ATP-binding site of the kinase (FDA, 2023). Despite high initial efficacy, patients often develop resistance through secondary ALK mutations or bypass signaling pathways, necessitating the development of next-generation inhibitors with broader mutational coverage and better CNS penetration (Journal of Clinical Oncology, 2021).

Other names

ALK rearrangementsALK fusionsEML4-ALKNPM-ALKKIF5B-ALKTFG-ALKRANBP2-ALK

Tyrosine kinase inhibition via competitive ATP binding