KLK15

KLK15 (kallikrein-related peptidase 15) is a member of the human kallikrein family of secreted serine proteases and functions primarily in extracellular proteolysis, a process implicated in tissue remodeling and cancer-associated microenvironmental regulation^[1][2]. KLK15 exhibits serine-type endopeptidase activity and participates in proteolytic pathways operating in the extracellular region, linking its biological function to protein substrate processing and cellular interactions with the surrounding matrix^[2][5]. Mechanistically, biochemical characterization demonstrated that KLK15 possesses trypsin-like enzymatic activity with preferential cleavage after arginine residues, and its activity is influenced by pH, cations, and serine protease inhibitors^[3]. Consistent with this proteolytic function, degradomic analyses identified interactions with extracellular matrix-associated substrates and pathways, suggesting a role in extracellular matrix remodeling and tumor progression-related processes^[3]. In disease contexts, increased KLK15 expression has been reported in prostate cancer, and multiple studies have evaluated KLK15 expression as a diagnostic or prognostic biomarker in prostate and ovarian malignancies^[1][6][7]. Compared with related kallikrein isoforms, KLK15 is distinguished by extensive alternative splicing that generates multiple transcript and protein isoforms, indicating a higher degree of transcript diversity than many family members and supporting isoform-specific biological investigation^[1][4]. For experimental applications, recombinant KLK15 has been used to define substrate specificity, characterize enzymatic regulation, and evaluate potential cancer-associated extracellular targets, providing a useful platform for mechanistic studies of kallikrein-mediated proteolytic networks^[3].