Objective: To study the expression of cyclooxygenase-2 (COX-2) gene in breast cancer and its clinicopathologic characteristics.
Methods: With beta-actin gene as reference, the COX-2 mRNA was monitored in 30 specimens of breast cancer tissue and adjacent normal breast tissue by reverse transcription-polymerase chain reaction (RT-PCR).
Results: The COX-2 mRNA expression was significantly upregulated in most breast cancer tissues with range of 0.05 - 0.91 (median 0.56), which was rare in normal breast tissue with range of 0 - 0.09 (median 0). The difference of COX-2 mRNA expression between cancer and normal breast tissue was significant (rank sum test, P < 0.05). COX-2 overexpression in breast cancer was related to its lymph node metastasis (P < 0.05) but not to age, tumor size, pathologic grade or pathologic type (P > 0.05).
Conclusion: The level of COX-2 mRNA expression is obviously higher in the breast cancer tissue than that in normal breast tissue. COX-2 overexpression may play a crucial role in the carcinogenesis, development of cancer and lymph node metastasis in breast cancer patients.