RESUMO
<p><b>OBJECTIVE</b>To investigate the expression of p120(ctn) in non-small cell lung cancer (NSCLC) and its correlation with the clinical and pathologic parameters.</p><p><b>METHODS</b>Immunohistochemistry (S-P method) was used to detect the expression of p120(ctn) in 143 NSCLC cases. The variation of protein expression was further analyzed in 36 cases by Western blot. The correlation with clinical and pathologic parameters was studied.</p><p><b>RESULTS</b>Immunohistochemically, normal bronchial cells showed membranous expression for p120(ctn), while NSCLC was characterized by cytoplasmic or diminished membranous staining. The rate of abnormal p120(ctn) expression was 79.7% (114/143). There was a significant correlation between abnormal expression of p120(ctn) and tumor differentiation, clinical stage, lymph node metastasis and poor prognosis (< 0.05), but not histologic typing. Western blot showed that the total amount of p120(ctn) in normal bronchial cells was significantly higher than that in NSCLC. The p120(ctn) isoform 1 (120,000) and isoform 3 (100,000) were expressed in normal lung tissue, while there was a reduced expression or absence of isoform 1 in NSCLC.</p><p><b>CONCLUSION</b>The expression of p120(ctn) is abnormal in NSCLC; p120(ctn) may serve as a useful prognostic marker for NSCLC.</p>