[Expression and function of cyclooxygenase-2 in endometrial carcinoma].

OBJECTIVE

To evaluate the cyclooxygenase-2(COX-2) expression at mRNA and protein levels, as well as its clinical significance, and to study the correlation of COX-2 with angiogenesis, apoptosis and estrogen or progestron receptors.

METHODS

Forty-one samples of normal endometrium tissues and 52 ones of endometrial carcinomas(EC) were collected, together with their corresponding clinical information. RT-PCR was adopted to determine the expression of COX-2 mRNA. Immunohistochemical staining was engaged to evaluate the protein expression of COX-2, VEGF, Bcl-2 and the MVD marked by CD105. And TUNEL was used to count the apoptosis cells.

RESULTS

(1)Significantly higher mRNA and protein levels of COX-2 were found in endometrial carcinomas than in normal endometrial tissues (P<0.001). (2)At protein level, COX-2 expression was related to the grade (P=0.020), but had nothing to do with the stage, pathological type, depth of myometrium invasion and lymph node metastasis.Neither did the level of COX-2 mRNA with all the factors above. (3)The level of COX-2 mRAN had nothing to do with that of protein(P=0.125, r=0.222). (4)The higher the expression of COX -2 protein was, the higher that of VEG, MVD or Bcl-2 was, and the lower the count of apoptosis cells was P<0.05. (5)The upregulation of COX-2 protein had no correlation with ER-alpha and ER-beta. But it had positive correlation with PRA and PRB, P was 0.031 and 0.007, respectively.

CONCLUSION

(1)The expression of COX-2 is significantly higher in EC than in normal endometrium tissue, not only at the mRNA level, but also at protein level. (2)At protein level, COX-2 expression is related to the grade, but has nothing to do with the stage, pathological type, depth of myometrium invasion and lymph node metastasis. Neither does the level of COX-2 mRNA with all the factors above. (3)The upregulation of COX-2 protein in EC correlates with the increase of VEGF protein and MVD. (4)The upregulation of COX-2 protein in EC correlates with the increase of Bcl-2 protein and the decrease of apoptosis cells. (5)The upregulation of COX-2 protein in EC has no significant correlation with ER expression, but has something to do with the increase of PRA and PRB.