Expression of GPC3 protein and its significance in lung squamous cell carcinoma

The purpose of this study was to investigate GPC3 gene expression in lung squamous cell carcinoma tissue and its correlation with clinical and tumor characteristics. Using RT-PCR, the presence of GPC3 gene expression was detected in cancer tissue and adjacent normal tissue in 66 cases of lung squamous cell carcinoma and positive rates were calculated. Using Western blot, changes in GPC3 protein expression were detected in lung squamous cell carcinoma and adjacent normal tissues. The percentage of tissue samples expressing GPC3 mRNA was significantly higher in lung squamous cell carcinoma than in adjacent normal tissue (P < 0.05). This percentage was also significantly higher for cases with lymph node metastasis than for those without lymph node metastasis (P < 0.05). Further, the percentage of samples expressing GPC3 mRNA was higher with lowering degrees of tumor differentiation (P < 0.05). Rates of GPC3 expression were, however, independent of patient gender, age, and tumor size (P > 0.05). The expression of GPC3 protein in lung squamous cell carcinoma was significantly higher than that in adjacent normal tissues (P < 0.05). The expression in cases with lymph node metastasis was significantly higher than in those without lymph node metastasis (P < 0.05), and GPC3 protein expression increased with lowering degrees of tumor differentiation (P < 0.05). Further investigation is warranted for the association of initiation, development, invasion, and metastasis of disease.