Abstract
Non-small-lung cancer (NSCLC) is a common malignant tumor and is a leading cause of cancer mortality. Tumor stem cells are associated with tumor pathogenesis and development as well as invastion and metastasis. In the present study, the expression and correlation of tumor stem cell markers, octamer-binding transcription factor 4 (Oct-4) and E-cadherin (E-cad) in NSCLC and normal lung tissue were investigated. Additionally, the molecular mechanisms of invasion and metastasis of NSCLC were assessed. The expression of Oct-4 and E-cad was examined in 65 pathologically diagnosed cases of NSCLC using immunohistochemistry. The correlation between Oct-4 and E-cad, as well as the association with pathological grade and clinical staging were also analyzed. Fifteen cases of normal lung tissues served as the control. The positive expression of Oct-4 and abnormal expression of E-cad was higher in the NSCLC tissue compared to the normal lung tissue, and increased as NSCLC malignancy increased. The differences in each grade each stage were statistically significant (P<0.05). A correlation was identified between the abnormal expression of Oct-4 and E-cad (P<0.05, coefficient of contingency C=0.439). In conclusion, the expression of Oct-4 promoted the epithelial-mesenchymal transition in lung cancer.