Interleukin-1 receptor-associated kinase 4 (IRAK4) (IRAK4)

Interleukin-1 receptor-associated kinase 4 (IRAK4) is a pivotal serine/threonine kinase that functions as a central mediator in the signaling pathways of the Toll-like receptor (TLR) and Interleukin-1 receptor (IL-1R) families (UniProt Q9NWZ3). Upon ligand binding to these receptors, IRAK4 is recruited to the Myddosome complex, where its kinase activity triggers a cascade involving IRAK1/2 and TRAF6, ultimately leading to the activation of NF-kappa-B and mitogen-activated protein kinases (MAPKs) (PubMed: 30108015). This signaling is essential for the production of pro-inflammatory cytokines and the initiation of the innate immune response. Dysregulation of IRAK4 is implicated in various autoimmune and inflammatory diseases, as well as certain malignancies, such as Waldenström macroglobulinemia and diffuse large B-cell lymphoma, particularly those with MYD88 mutations (PubMed: 32810034). Therapeutic targeting of IRAK4 involves small molecule inhibitors and proteolysis-targeting chimeras (PROTACs) designed to dampen pathological inflammation or inhibit tumor growth (ClinicalTrials.gov: NCT04772885). However, clinical development must account for the risk of increased susceptibility to pyogenic bacterial infections, a phenotype observed in patients with primary IRAK4 deficiency (PubMed: 15351781).

Other names

IRAK-4NY-REN-64Renal carcinoma antigen NY-REN-64

Inhibition of kinase activity to block downstream pro-inflammatory signaling; targeted protein degradation via PROTACs.