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Expression of cell cycle-associated proteins CDK4, p27, and E2F-1 in chondrosarcoma of the jaws
1Department of Endodontics, School of Stomatology, Shanghai Second Medical University, Shanghai 200011, P. R. China.
Objective:
To elucidate the expression and significance of cell cycle-associated proteins in chondrosarcoma of the jaws.
Methods:
CDK4, p27, and E2F-1 expression were examined in chondrosarcoma and osteochondroma of the jaws by immunohistochemical ABC method.
Results:
CDK4, p27, and E2F-1 were positive in 60% (12 of 20), 25% (5 of 20), and 65% (13 of 20), respectively, in chondrosarcoma of the jaws. There was no significant difference in the expression of CDK4, P27, and E2F-1 among histological grade of the chondrosarcoma (P > 0.05). In osteochondroma of the jaws, CDK4 and E2F-1 showed an equal positivity of 12.5% (1 of 8), whereas p27 was positive in 87.5% (7 of 8). The positive rate of CDK4, p27, and E2F-1 was significant between chondrosarcoma and osteochondroma of the jaws (P < 0.05).
Conclusion:
These data show that cell cycle regulatory proteins are altered in chondrosarcoma of the jaws. CDK4 and E2F-1 are over-expressed and p27 is under-expressed in chondrosarcoma of the jaws.
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