Abstract: Objective: To detect the expression of aldehyde dehydrogenase1A1 (ALDH1A1) in the primary lesions and lymph nodes of tongue squamous cell carcinoma (TSCC) patients, and analyze the their relationship with clinicopathological features and prognosis. Methods: The expression of ALDH1A1 was evaluated by SP immunohistochemistry in 50 cases of TSCC primary lesions, 10 cases of normal tongue tissue and 29 metastatic lymph nodes, 9 non-metastatic lymph nodes. Results: Expression of ALDH1A1 in TSCC primary lesions was significantly higher than that in normal tongue tissue (P<0.05). Expression of ALDH1A1 in metastatic lymph nodes was significantly higher than that in non-metastatic lymph nodes (P<0.05). In primary TSCC lesions, the expression level of ALDH1A1 was associated with clinical stage, lymph node metastasis, tumor size and histological grade (P<0.05). In lymph nodes, the expression level of ALDH1A1 was associated with clinical stage, lymph node metastasis and tumor size (P<0.05). The Kaplan-Meier analysis demonstrated that ALDH1A1 overexpression was associated with poor prognosis in TSCC patients. Conclusion: ALDH1A1 was closely correlated with the biological behavior and prognosis of patients in TSCC, and may provide new therapeutic targets for TSCC.

Key words: Tongue squamous cell carcinoma, Lymph node , Aldehyde dehydrogenase1, A1Cancer stem cell, Prognosis