After August 17, 2026, Novus Biologicals products and services will no longer be available on this website; you will access all products and services on rndsystems.com. Create your R&D Systems online account today.
Cathepsins are lysosomal proteases that play an important role in the intracellular degradation of exogenous and endogenous proteins, activation of enzyme precursors, and tumour invasion and metastasis. Normally located in lysosomes of almost all mammalian cells, they can be secreted from the cell under certain conditions. Cathepsin L is responsible for most of the intralysosomal breakdown of normal cells. Cathepsin L is secreted by numerous transformed cells in its inactive proform, and mRNA expression level seems to correlate with their metastatic potential.