Clinicopathologic significance of β-catenin and matrix metalloproteinase-2 expression in non-small cell lung cancer

The purpose of this study was to analyze β-catenin and matrix metalloproteinase-2 (MMP-2) expression in non-small cell lung cancer (NSCLC) and to investigate the association between their expression and clinicopathologic characteristics of NSCLC patients. Immunohistochemistry was performed to examine β-catenin and MMP-2 protein expression in 39 resected NSCLC samples and 8 adjacent normal lung tissues. Statistical analysis with SPSS13.0 software was performed to investigate the association between β-catenin and MMP-2 expression and clinicopathologic features of the patients. Expression of cytosolic β-catenin in NSCLC tissue was significantly higher than that in normal tissues (P < 0.001). In addition, cytosolic protein expression of β-catenin in lung squamous cell carcinoma was significantly elevated compared to that in lung adenocarcinoma (P = 0.02). However, cell membrane protein expression of β-catenin in squamous cell carcinoma was lower than that in adenocarcinoma (P = 0.041). Cytosolic MMP-2 protein expression in NSCLC samples was significantly higher than that in normal tissues (P = 0.002). MMP-2 expression in N _1–2 NSCLC patients was significantly increased relative to N ₀ patients (P = 0.019). However, statistical analysis showed no correlation between β-catenin and MMP-2 expression in NSCLC samples. Collectively, our results show that cytosolic protein expression of β-catenin in NSCLC samples is increased relative to normal lung tissues. Also, expression of β-catenin is significantly elevated in squamous cell carcinoma compared to that in lung adenocarcinoma subtypes. Additionally, MMP-2 expression in N _1–2 NSCLC tissues is higher than that in N ₀ lung tissue. There is no correlation between β-catenin and MMP-2 expression in NSCLC, and our study suggests that evaluation of β-catenin and MMP-2 expression may have potential in diagnosis and progression in patients with NSCLC.