Abstract
Esophageal carcinoma is the most common type of tumor, with the incidence in China accounting for 50% of cases worldwide and the majority of patients not surviving due to tumor recurrence. According to the cancer stem cell theory, tumor development and recurrence is due to the excitation of a cancer stem cell. Aldehyde dehydrogenase 1 (ALDH1) is an appropriate marker for cancer stem cells and the present study aimed at determining the function of ALDH1 in human esophageal carcinoma. Indirect fluorescence antibody staining was used to investigate the association between the level of ALDH1 protein expression and clinicopathological parameters, including sex, age, vein invasion, degree of tumor cell differentiation and clinical stage. DAPI was used to stain the nuclei of tumor cells and exclude non-tumor cells. The results of the present study revealed that ALDH1 expression was associated with the level of tumor cell differentiation, tumor-node-metastasis stage and lymphatic invasion. In addition, increased expression of ALDH1 was identified in esophageal carcinoma tissues compared with in healthy esophageal tissues. Therefore, ALDH1 may be used as a parameter for the pathology of esophageal carcinoma.