Neutrophil elastase (ELANE) (ELANE)

Neutrophil elastase (ELANE) is a 218-amino acid serine protease primarily synthesized in promyelocytes and stored in the azurophilic granules of mature neutrophils [UniProt: P08246]. It plays a critical role in the innate immune system by degrading engulfed pathogens and remodeling the extracellular matrix at sites of inflammation. In oncology, the ELANE pathway has emerged as a novel mechanism for selective cancer cell destruction; ELANE released by neutrophils can enter cancer cells and trigger apoptosis by cleaving the CD95 death receptor, a process that appears to spare normal cells due to their higher expression of endogenous protease inhibitors like alpha-1 antitrypsin [PubMed: 34043952]. Beyond its anti-tumor potential, ELANE is a well-established driver of tissue damage in chronic inflammatory diseases such as COPD and cystic fibrosis, where its activity is unopposed by natural inhibitors. Therapeutic strategies involving ELANE include the use of small-molecule inhibitors like Sivelestat to treat acute lung injury and the exploration of ELANE-based biologics for targeted cancer therapy. Mutations in the ELANE gene are also the primary cause of severe congenital neutropenia and cyclic neutropenia, highlighting its essential role in hematopoiesis.

Other names

Neutrophil elastaseELA2Polymorphonuclear leukocyte elastaseBone marrow serine proteaseMedullasinHuman leukocyte elastase (HLE)

ELANE acts as a serine protease that cleaves various protein substrates. In cancer cells, it selectively triggers apoptosis by cleaving the CD95 (Fas) receptor, releasing the Fas intracellular domain (Fas-ICD) which activates the extrinsic apoptotic cascade [PubMed: 34043952]. In inflammatory contexts, it degrades elastin and other extracellular matrix proteins, facilitating leukocyte migration but also potentially causing tissue damage if not regulated by endogenous inhibitors.