Nasopharyngeal carcinoma(NPC)is one of the most common cancers in Southern China.Aldo-keto reductase 1B10(AKR1B10)is upregulated in multiple tumors and plays an oncogenic role.In this study,we used immunohistochemistry staining,Western blot and quantitative real time RT-PCR to examine the expression of AKR1B10 at the mRNA and protein levels in NPC and precancerous nasopharyngeal specimens.We found that AKR1B10 expression was increased in malignant tissues compared to normal tissues(p=0.000).In NPC tissues,high AKR1B10 expression appeared specifically in squamous cell carcinoma,but not in basal cell carcinoma,adenoid cystic carcinoma,adenocarcinoma and undifferentiated carcinoma(p=0.000).AKR1B10 expression also demonstrated correlation with differentiation with a high level in well and moderately differentiated squamous cell carcinoma,but the expression level was low in poorly differentiated squamous cell carcinoma(p=0.000).AKR1B10 was also upregulated in hyperplasia and benign tumors(p=0.000),and demonstrated a specific nuclear distribution.Taken together,this study provides for the first time evidence that AKR1B10 is overexpressed in NPC and precancerous lesions,being a potential new biomarker of nasopharyngeal neoplasms.The increased expression and nuclear location of AKR1B10 in precancerous lesions may imply its promoting role in the development and malignant progression of nasopharyngeal tumors.