RESUMEN
BACKGROUND & OBJECTIVE: PTEN/PI3K signal transduction pathway regulates cell proliferation and survival, and is closely associated with the development and progress of various tumors. However, the relationship between the function of this pathway with lung carcinoma has not been completely elucidated. This study was to investigate the expression and clinical significance of PTEN/PI3K signal transduction-related proteins, such as insulin-like growth factor-1 receptor (IGF-1R), PTEN and phosphatidylinositol 3-kinase (PI3K), in non-small cell lung carcinoma (NSCLC). METHODS: The expression of IGF-1R, PTEN, and PI3K in 59 specimens of primary NSCLC, 19 specimens of metastatic lymph nodes, 16 specimens of para-cancerous hyperplastic lung tissues, and 7 specimens of normal lung tissues were detected by SP immunohistochemistry. The difference of positive rates of IGF-1R,PTEN and PI3K was evaluated by Chi-square test and Fisher's exact test. RESULTS: The positive rates of IGF-1R, PTEN, and PI3K in NSCLC were 72.88%, 27.12%, and 84.75%, respectively. The positive rates of IGF-1R and PI3K were not associated with the clinicopathologic features of NSCLC (P>0.05). The positive rate of PTEN was highly associated with lymph node metastasis of NSCLC (P=0.009), but was not associated with pathologic type and differentiation grade of NSCLC (P>0.05). The positive rate of PTEN was significantly lower and that of PI3K was significantly higher in NSCLC and metastatic lymph node tissues than in para-cancerous hyperplastic and normal lung tissues (P<0.05). The expression of IGF-1R in NSCLC was positively correlated to that of PI3K (r=0.432, P=0.001); while the expression of PTEN was negatively correlated to that of PI3K (r=0.505, P<0.001). CONCLUSION: Overexpression of IGF-1R and PI3K, and low expression of PTEN are closely correlated to the development, invasion and metastasis of NSCLC.