[One of three inhibitory families in the cystatin superfamily (including type 2 cystatins and kininogens), Stefin Family Genes (type 1 cystatins) encode intracellular cysteine thiol protease inhibitors of papain and cathepsins B, H, and L. Cystatin Superfamily proteins contain multiple cystatin-like sequences; some are active cysteine protease inhibitors, while others have lost or perhaps never acquired this activity. (NCI) ( NCI )]
UMLS (NCI) C1336499Stefin Family Gene