KLK9 (kallikrein-related peptidase 9) is a member of the human tissue kallikrein family, which comprises 15 serine proteases (KLK1-KLK15) involved in diverse physiological and pathological processes, including tissue remodeling, inflammation, and cancer progression. KLK9 is encoded by the KLK9 gene located on chromosome 19q13.4 and is expressed in various tissues, such as the prostate, breast, brain, and salivary glands. Functionally, KLK9 exhibits proteolytic activity, cleaving extracellular matrix components and regulating signaling pathways. Its dysregulation has been linked to cancers (e.g., ovarian, breast) and neurodegenerative diseases (e.g., Alzheimer’s), though its precise mechanisms remain less characterized compared to other KLKs.
KLK9 antibodies are essential tools for studying its expression, localization, and role in diseases. They enable detection via techniques like immunohistochemistry, Western blotting, and ELISA, aiding in biomarker discovery and therapeutic research. Some studies suggest KLK9 overexpression in tumor tissues, correlating with aggressive phenotypes, making it a potential diagnostic or prognostic marker. However, challenges persist in understanding its substrate specificity and regulatory pathways. Current research focuses on developing highly specific monoclonal antibodies to improve diagnostic accuracy and explore therapeutic applications, such as blocking KLK9 activity or targeting drug delivery. Further validation is needed to establish its clinical utility and mechanistic contributions to disease.