title: Expression of cysteine proteinases cathepsins B and K and of cysteine proteinase inhibitor cystatin C in giant cell tumor of tendon sheath.
abstract: The expression of cysteine proteinases cathepsins B and K and of the endogenous inhibitor of cysteine proteinases, cystatin C, was investigated in tissue specimens of patients with giant cell tumor of tendon sheath (GCTTS). Expression of both enzymes was examined by immunohistochemistry in tissue specimens of 14 patients with GCTTS. Applying double-labeling techniques, the coexpression of cathepsin B and its major endogenous inhibitor cystatin C was additionally studied. Cells expressing the respective proteins were further characterized with the macrophage markers HAM56 and anti-CD68 (clone PG-M1). Cathepsin B could be detected in numerous HAM56-positive mononuclear cells (MC), but only in very few giant cells (GC). In contrast, cathepsin K was predominantly identified in GC that were also strongly immunoreactive for cystatin C and CD68. Coexpression of cathepsin B and cystatin C occurred only in a few MC. The strong expression of both cathepsin B and K suggests that in GCTTS, bone erosion might be mediated not only by pressure of the proliferative tissue, but also by matrix-degrading cysteine proteinases. Because previous studies showed that osteoclasts express high levels of CD68, cathepsin K, and cystatin C but not of cathepsin B, our study contributes to the view that GC of GCTTS and osteoclasts are closely associated.
authors: Institute of Pathology, Johannes Gutenberg-University, Mainz, Germany.
authors: T
authors: T
authors: Hansen
authors: P K
authors: PK
authors: Petrow
authors: A
authors: A
authors: Gaumann
authors: G M
authors: GM
authors: Keyszer
authors: M
authors: M
authors: Otto
authors: C J
authors: CJ
authors: Kirkpatrick
authors: J
authors: J
authors: Kriegsmann
mesh_terms: D000328:Adult; D000368:Aged; D000911:Antibodies, Monoclonal / Q000378:metabolism; D015703:Antigens, CD / Q000378:metabolism; D015214:Antigens, Differentiation, Myelomonocytic / Q000378:metabolism; D002401:Cathepsin B / Q000378:metabolism*; D056657:Cathepsin K; D002403:Cathepsins / Q000378:metabolism*; D002452:Cell Count; D055316:Cystatin C; D015891:Cystatins / Q000378:metabolism*; D015853:Cysteine Proteinase Inhibitors / Q000378:metabolism*; D005260:Female; D005870:Giant Cell Tumors / Q000201:enzymology* / Q000473:pathology; D015726:Giant Cells / Q000201:enzymology / Q000473:pathology; D006801:Humans; D007124:Immunoenzyme Techniques; D007963:Leukocytes, Mononuclear / Q000201:enzymology / Q000473:pathology; D008297:Male; D008875:Middle Aged; D019042:Muscle Neoplasms / Q000201:enzymology* / Q000473:pathology; D013710:Tendons / Q000473:pathology*; D000097382:CD68 Molecule
chemical_list: D000911:Antibodies, Monoclonal; D015703:Antigens, CD; D015214:Antigens, Differentiation, Myelomonocytic; D002401:Cathepsin B; D056657:Cathepsin K; D002403:Cathepsins; D055316:Cystatin C; D015891:Cystatins; D015853:Cysteine Proteinase Inhibitors; C067980:CD68 antigen, human; D000097382:CD68 Molecule; C525030:CST3 protein, human; C096893:HAM-56 antibody; C534130:CTSK protein, human