Increased expression of COX-2 in recurrent basal cell carcinoma of the skin: A pilot study.

Introduction: Basal cell carcinoma (BCC) is the most frequent malignant skin tumor. BCC rarely metastasizes, but it is often locally aggressive. Cyclooxygenase-2 (COX-2) is critical for tumor formation, angiogenesis and metastasis. Matrix metalloproteinases (MMPs) are the members of the family of zinc (Zn)- and calcium-dependent endopeptidases that degrade the extracellular matrix. Materials and Methods: In our study, we used immunohistochemical methods for the evaluation of COX-2, MMP-2 and MMP-9 expression in tissue samples of 30 primary and 10 recurrent skin BCC cases. Results: Immunohistochemical COX-2 expression was significantly higher in the infiltrating pattern of BCC compared with the nodular (P = 0.005) and superficial (P = 0.041) subtypes in the primary BCC group. There was not a significant difference between nodular and superficial BCCs for COX-2 expression. In addition, COX-2 expression was significantly higher in the recurrent BCC group than in the primary BCC group (P = 0.030). There was no statistically significant difference between the histological subtypes of primary BCCs and between primary and recurrent BCCs for MMP-2 and MMP-9 expressions. Conclusions: Our data confirm previous findings that COX-2 and MMP-9 expressions are increased in BCC. Our results revealed an elevated COX-2 expression in recurrent BCCs. We suggest that COX-2 inhibition might have beneficial effects in BCCs, especially for the tumors with a higher level of COX-2 expression or aggressive phenotype.

Cyclooxygenase-2 expression in primary and recurrent pterygium.

BACKGROUND: Pterygia are common, benign, fibrovascular, and infiltrative processes of the corneo-conjunctival junction of unknown pathogenesis. Cyclooxygenase-2 (COX-2) mediates the rate-limiting step in arachidonic acid metabolism. Extensive evidence indicates that the COX-2 prostanoid pathway is involved in inflammation. The aim of the study was to document the immunohistochemical expression of COX-2 in primary and recurrent pterygia. MATERIALS AND METHODS: In this study, 21 primary pterygia and 12 recurrent pterygia from subjects undergoing pterygium surgery and six normal corneal-scleral tissue specimens were studied immunohistochemically for COX-2 expression. RESULTS: COX-2 was expressed in primary pterygia and recurrent pterygia specimens. There was a statistically significant difference in COX-2 expressions in fibroblasts between primary and recurrent pterygium cases ( P = 0.001). There were statistically significant differences in COX-2 expressions in surface epithelium ( P = 0.028) and stromal inflammatory cells ( P =0.000) between control tissues and primary pterygia tissues. We also detected statistically significant differences in COX-2 expressions in surface epithelium ( P =0.000), stromal fibroblasts P =0.000 (stromal fibroblasts and inflammatory cells), vessels ( P = 0.027) and inflammatory cells ( P =0.001) between control tissues and recurrent pterygia tissues. CONCLUSIONS: This is the first study to document the expression of COX-2 in primary and recurrent pterygia. In our opinion after excision of pterygia, fibroblastic proliferation continues and this contributes to recurrence.