Expression of high molecular weight cysteine proteinase inhibitor in ovarian cancer tissues: regulation of cathepsin B expression by placental CPI.
Mouse polyclonal antibodies against placental cysteine proteinase inhibitor (CPI) react with the placental 67 kDa CPI on Western blots, and CPI present in ovarian cancer homogenate and serum was shown by double immunodiffusion to react with the same antiserum. By immunohistochemical staining, positive expression of high molecular weight CPI was observed on the tumour cell surface in serous and endometrioid ovarian carcinomas with metastasis. Normal endometrioid tissue was not stained with anti-placental CPI antibodies. Cathepsin B and pro-cathepsin B median levels in ovarian cancer tissue homogenates increased progressively with FIGO stage of the disease. The enzyme level decreased 22-fold after treatment of tissue homogenates with 5 nM purified CPI. These results provide evidence that addition of CPI reduces the levels of cysteine-type cathepsins to those of normal non-cancerous values.
Siewiński
Maciej
M
Department of Obstetrics and Gynaecology, Wrocław Medical University, 3 Chałubińskiego, 50-368 Wrocław, Poland.
Saleh
Yousif
Y
Popiela
Andrzej
A
Ziółkowski
Piotr
P
Jeleń
Michał
M
Gryboś
Marian
M
D000328:Adult; D000906:Antibodies / Q000276:immunology*; D002401:Cathepsin B / Q000096:biosynthesis / Q000378:metabolism*; D015853:Cysteine Proteinase Inhibitors / Q000096:biosynthesis / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D004792:Enzyme Precursors / Q000378:metabolism; D005260:Female; D015870:Gene Expression; D006801:Humans; D007150:Immunohistochemistry; D008875:Middle Aged; D008970:Molecular Weight; D010051:Ovarian Neoplasms / Q000378:metabolism* / Q000473:pathology; D010920:Placenta / Q000201:enzymology / Q000276:immunology / Q000378:metabolism*; D014020:Tissue Extracts / Q000378:metabolism
D000906:Antibodies; D015853:Cysteine Proteinase Inhibitors; D004792:Enzyme Precursors; D014020:Tissue Extracts; C057832:procathepsin B; D002401:Cathepsin B