Clinicopathological Significance of E-Cadherin and PCNA Expression in Human Non-Small Cell Lung Cancer

This study was designed to assess E-cadherin (E-cad)and proliferating cell nuclear antigen (PCNA)expression as well as their clinicopathological significance in human non small cell lung cancers (NSCLCs). Possible molecular mechanisms of differentiation and metastasis of NSCLCs are discussed. Immuno-histochemical and immunofluorescence double staining were performed to examine the expression of E-cad and PCNA in 68 primary NSCLCs cases. The E-cad expression in squamous cell carcinomas and adenocarcinomas showed no significant difference. E-cad expression had a positive correlation with the histological-diferentiated grade. A significant difference of E-cad expression was found between metastatic and non-metastatic groups. PCNA expression in squamous cell carcinomas and adenocarcinomas showed no significant difference. The PCNA expression had a reverse correlation with the histological-differentiated grade. A significant difference of PCNA expression was found between m etastatic and non-metastatic groups. The E-cad and PCNA expression presented a reverse correlation. E-cad expression is not associated with the histological type of NSCLC, but is associated with differentiation and metastasis of the cancer. Down-regulation of E-cad expression affects the proliferation of cancer cells. Conjoint analysis of E-cad and PCNA expression is a good way to evaluate tumor biological behavior.