Expression And Significance Of Cyclo-oxygenase-2 In Chordoma

Chordoma, a rare and low degree malignant tumor of bone, is considered to originate from remnants of the notochord, which is a slowly growing tumor and is frequently located at both ends of the axial skeleton, but most frequently at the sacral bone. Because of its proximity to vital neurovascular structures and their propensity to diffusely invasion, chordoma is difficult to cure and is easy to local recurrences. Today, the development and progression of chordoma is unclear and there is no effective method for diagnosis of chordoma. Therefore, In investigation of tumor of bone, the biological features of chordoma is one of focus.Cyclooxygenase is the key rate - limiting enzyme in prostaglandin biosynthesis. Expression of cyclooxygenase - 2 ( COX - 2 ) , a isoenzymes of cyclooxygenase, is induced by various stimuli such as growth factors, cytokines, cancer gene. COX - 2 may promote cell proliferation and the growth of tumor vessle, affect anti - oncogene and the function of immunocyte, suppress apoptosis, et al. It plays an important role in the development and progression of tumor. In a lot of studies, COX -2 is overexpressed in various tumor cells. However, expression and localization of COX - 2 protein in chordoma have not been reported.In order to develop the diagnosis and treatment of chordoma, we study expression of COX - 2 in chordoma by immunohistochemical a-nalysis (S - P) and the role in the development and progression of chordoma.MATERIALThe specimens of chordoma, which were diagnosed as chordoma by pathology after operation, obtained from 18 patients at the First and Third Affiliated Hospital of China Medical University, Shen Yang Central Hospital. 24 embryo - fetal specimens, as control, obtained from Shen Yang Women and Children Hospital. Antibody of COX - 2 were bought from Boster Biotechnology CO. LTD. S -p test kit, DAB substrate test kit and 10% blood serum of goat were bought from Beijing ZongShan biotechnology CO. LTD.METHODSIn this experiment, we examine the protein of COX -2 in 18 specimens of chordoma and 24 embryo - fetal specimens by immuno-histochemical analysis ( S - P) , account the rate of expression COX -2 and analyze average OD by the system of analyzing image. Difference between the groups were analyzed by either the x - test or t -test.RESULTSEnhanced COX - 2 expression was observed in chordoma cytoplasm. The rate of expression of COX - 2 was 66. 7% in the specimens of chordoma and 29.2% in the embryo - fetal plate specimens.Average OD is 41. 34 ±25. 00 in the specimens of chordoma and 17. 97±27.42 in the embryo - fetal plate specimens. The extent and intensity of the immunoreactive COX - 2 in the specimens of chordoma was much greater than that of embryo - fetal specimens ( P <0.05 ).CONCLUSION1. There are a lot of COX - 2 proteins in chordoma and COX - 2 protein plays an important role in the development and progression of chordoma.2. COX - 2 protein is one of the marker of diagnoses of chordoma.