Proto-oncogene tyrosine-protein kinase ROS1 fusion protein (ROS1 fusion)

ROS1 fusion proteins are chimeric oncoproteins formed by chromosomal rearrangements that join the C-terminal kinase domain of the ROS1 receptor tyrosine kinase with various N-terminal fusion partners, such as CD74, SLC34A2, or SDC4 (UniProt P08922). These fusions result in the constitutive, ligand-independent activation of the ROS1 kinase domain, which drives oncogenic signaling through the PI3K/AKT/mTOR, RAS/MAPK/ERK, and JAK/STAT3 pathways (PubMed: 28490440). Primarily identified in approximately 1-2% of non-small cell lung cancer (NSCLC) cases, ROS1 fusions also serve as drivers in glioblastoma, cholangiocarcinoma, and other solid tumors (PubMed: 30107109). Therapeutic strategies focus on small-molecule tyrosine kinase inhibitors (TKIs) like crizotinib, entrectinib, and repotrectinib, which bind to the ATP-binding pocket of the kinase domain to inhibit downstream signaling (FDA.gov). While initial responses are often significant, clinical management is frequently challenged by the emergence of acquired resistance mutations, most notably the G2032R solvent front mutation, necessitating the use of next-generation inhibitors designed to overcome these specific structural changes (PubMed: 31462516).

Other names

c-Ros receptor tyrosine kinaseROS proto-oncogene 1ROS1 rearrangementROS1-fused receptor tyrosine kinaseMCF3

Small molecule inhibition of the ROS1 tyrosine kinase domain by competitive binding to the ATP-binding site, preventing autophosphorylation and downstream oncogenic signaling.