Immunohistochemical expression of p27 and p21 in canine cutaneous mast cell tumors and histiocytomas.
The objective of this study was to evaluate by immunohistochemical means the nuclear expression of p27 and p21 proteins in cutaneous mast cell tumors and histiocytomas of dogs. In mast cell tumors, nine of the 13 grade I tumors, 13 of the 19 grade II tumors, and 10 of the 15 grade III tumors showed no detectable or mild p27 immunoreactivity. In contrast, one of the 13 grade I tumors, 12 of the 19 grade II tumors, and 11 of the 15 grade III tumors showed moderate or marked p21 immunoreactivity. Nineteen of the 28 histiocytomas showed no detectable or mild p27 immunoreactivity, and 24 cases showed moderate or marked p21 immunoreactivity. These findings indicate that a loss or absence of p27 expression is an early pathogenic event in mast cell and histiocyte tumorigenesis and that p21 expression may be a marker of mast cell tumor progression and histiocytoma cell proliferation.
Wu
H
H
Department of Veterinary Pathology, Faculty of Agriculture, Yamaguchi University, 1677-1 Yoshida, Yamaguchi 753-8515, Japan.
Hayashi
T
T
Inoue
M
M
D000818:Animals; D018797:Cell Cycle Proteins / Q000378:metabolism*; D050759:Cyclin-Dependent Kinase Inhibitor p21; D050760:Cyclin-Dependent Kinase Inhibitor p27; D016213:Cyclins / Q000378:metabolism*; D004283:Dog Diseases / Q000378:metabolism*; D004285:Dogs; D018219:Histiocytoma, Benign Fibrous / Q000378:metabolism / Q000662:veterinary*; D007150:Immunohistochemistry; D008407:Mast Cells / Q000378:metabolism*; D012878:Skin Neoplasms / Q000378:metabolism / Q000662:veterinary*; D025521:Tumor Suppressor Proteins / Q000378:metabolism*
D018797:Cell Cycle Proteins; D050759:Cyclin-Dependent Kinase Inhibitor p21; D016213:Cyclins; D025521:Tumor Suppressor Proteins; D050760:Cyclin-Dependent Kinase Inhibitor p27