Expression and Clinical Significance of CD82/KAI1 and E-cadherin in Non-Small Cell Lung Cancer

This study investigates the expression of CD82/KAI1 and epithelial-cadherin (E-cad) in non-small cell lung cancer (NSCLC). Tissues of resected primary NSCLC and normal lung tissue were investigated. Protein expression was detected with immunohistochemical staining. mRNA expression levels of CD82/KAI1 and E-cad were determined by semiquantitative reverse transcriptase polymerase chain reaction (RT-PCR) after mRNA extraction. The expression of CD82/KAI1 and E-cad was significantly lower in NSCLC compared to normal lung tissue (P < 0.01). CD82/KAI1 and E-cad mRNA and protein expression were found to be in close relationship with the grade of differentiation, lymph node metastasis and pathologic tumor-node-metastasis (pTNM) stages, and survival in NSCLC (P < 0.01), but no relationship was observed with gender, diameter, type, histological type and age (P > 0.05). Expression of mRNA CD82/KAI1 and E-cad were consistent with their proteins (P < 0.01), and there was a significant relationship between expression of CD82/KAI1 and E-cad. The survival rate of the CD82/KAI1-positive and CD82/KAI1-negative groups was significantly different (P < 0.01). In addition, the survival rate was significantly different between the E-cad-positive and E-cad-negative groups. pTNM stages and positive expression of CD82/KAI1 and E-cad were independent prognostic factors of NSCLC (P < 0.05). Lower expression of CD82/KAI1 and E-cad was found in NSCLC compared to normal lung tissue. Decreased expression of CD82/KAI1 and E-cad was closely related to cellular differentiation, pTNM stages, invasion and metastasis.