摘要: | Tumor recurrence and distant metastasis are major causes of treatment failure in the oral cancer. Rapid growth of tumor cells and increased expressions of dihydrodiol dehydrogenase (DDH) and cyclooxygenase-2 (COX2) genes in tumor cells have been suggested as the important mechanisms for the disease progression. Interestingly, DDH1 and DDH2 also express PGF synthase activities. In this study we, therefore, investigated the prognostic significance of DDH expression in patients with oral cancer. By using immunohistochemistry, we measured DDH expression in 251 patients with oral cancer. Relation between DDH expression and clinicopathological parameters (age, gender, smoking history, mitotic index, histological type, stage, cell differentiation, and lymphovascular invasion) was analyzed by Chi-Square analysis. Our results showed that DDH overexpression could be detected in 193 (76.9%) of 251 pathological sections and in 65.0% (52/80) of metastatic lymph nodes. Expression of DDH was confirmed by immunoblotting and reverse transcription-polymerase chain reaction technique (RT-PCR). Compared to patients with DDH overexpression in tumors, patients with low DDH expression had significantly lower incidence of early tumor recurrence and distant organ metastasis (24.2% vs. 7.8%, p = 0.021). Using univariate analysis, DDH overexpression, tumor stages, and gender were three important factors correlated with poor prognosis for patients with oral cancer. Interestingly, DDH overexpression was closely correlated with patients’ betel nut chewing habit. However, biological function and involvement of DDH in the disease progression of oral cancer remains to be clarified by further studies. |