High ALDH1A1 expression correlates with poor survival in papillary thyroid carcinoma

BACKGROUND High expression of aldehyde dehydrogenase 1 (ALDH1) has been confirmed in many tumors. This enzyme plays an important role in tumor proliferation, metastasis, and drug resistance. However, in the case of papillary thyroid carcinoma (PTC), the relationship between ALDH1 expression and prognosis remains unknown. METHOD We used tissue microarrays to evaluate ALDH1A1 expression in 247 surgically resected PTC specimens by immunochemistry, and correlated the findings with the clinicopathological parameters. RESULT ALDH1A1 levels were significantly higher than in normal thyroid tissues. Moreover, ALDH1A1 overexpression was significantly associated with extrathyroid extension (P = 0.001), pT status (P < 0.001), pN status (P = 0.016) and TNM stage (P < 0.001). The Kaplan-Meier survival analysis suggested that high ALDH1A1 expression reflects a poorer lymph node recurrence-free survival (LN-RFS) and distant recurrence-free survival (DRFS) in PTC patients, as compared with patients having low ALDH1A1 expression. Multivariate analysis confirmed the ALDH1A1 expression was an independent prognostic factor for LN-RFS and DRFS in PTC patients. CONCLUSION In conclusion, high ALDH1A1 expression correlates with poor survival in PTC patients.