Latexin (LXN) (LXN)

Latexin (LXN) is a highly conserved protein and the only known endogenous inhibitor of zinc-dependent metallocarboxypeptidases, such as carboxypeptidase A (CPA1, CPA2, CPA4) and B (CPB1), in mammals [11]. It plays a critical role as a tumor suppressor, with its expression frequently lost or downregulated through promoter hypermethylation in various cancers, including leukemia, lymphoma, and gastric and prostate carcinomas [2, 8, 11]. In addition to its role in oncology, latexin is a key homeostatic regulator of the hematopoietic stem cell (HSC) pool, where it limits stem cell self-renewal and promotes apoptosis [8, 9]. Its expression is also linked to inflammatory responses, particularly in mast cells, and it serves as a marker for specific neuronal populations in the brain [2, 9]. Although no direct small-molecule inhibitors or activators of latexin are currently in clinical use, its potential as a therapeutic target is being explored, with studies showing that its expression can be modulated by agents like retinoic acid and DNA methyltransferase inhibitors [4, 8].

Other names

LXNEndogenous carboxypeptidase inhibitorECP-ITissue carboxypeptidase inhibitorTCIMUM

Latexin acts as a non-competitive inhibitor of zinc-dependent metallocarboxypeptidases, including CPA1, CPA2, and CPA4 [11]. It functions as a tumor suppressor by downregulating anti-apoptotic genes such as Bcl-2 and Pim-2 and negatively regulating the self-renewal of hematopoietic stem cells [8, 9].