IMMUNOHISTOCHEMICAL ANALYSIS OF CELL CYCLE-ASSOCIATED PROTEINS IN OSTEOSARCOMA OF THE JAWS

Objective To analyze the expression of cell cycle-associated proteins in osteosarcoma of the jaws. Methods Cyclin D1 , CDK4 , p27, E2F-1 and Ets-1 expression were examined semi-quantitatively in 20 osteosarcoma and 8 osteochondroma of the jaws by immunohistochemical ABC method. Results The positive rates of cyclin D1, CDK4 , p27, E2F-1 and Ets-1 were 65% ( 13 of 20), 60% ( 12 of 20), 20% (4 of 20),70% ( 14 of 20 ) and 55% ( 11 of 20 ) in osteosarcoma of the jaws, respectively. There was no remarkable difference in the expression of these proteins among histopathological types ( P ＞ 0. 05 ). In osteochondroma of t he jaws, the Positi ye ra res of CDK4 and E2F- 1 were both 12.5 % ( 1 of 8 ), whereas t ha t of p27 was 75 % ( 6 of 8). None of osteochondroma was positive for cyclin D1 and Ets-1. The positive rates of cyclin D1, CDK4,E2F-1 and Ets-1 were significantly higher while that of p27 was lower in osteosarcoma than that in osteochondroma of the jaws ( P ＜ 0. 05 ). In addition, the metastatic osteosarcoma of the jaws had higher Positive rate of Ets- 1 than that of the non-metastatic ( P ＜ 0 . 05). Conclusion The results suggest that the dysregulation of cell cycle-asso-ciated proteins may be involved in the occurrence and development of osteosarcoma of the jaws.