Protein Expression and Significance of VEGF, EGFR and MMP-9 in Non-Small Cell Lung Carcinomas

Objective: This study was designed to detect the protein expression of VEGF, EGFR and MMP-9, to investigate the potential roles they might play in the pathogenesis of NSCLC and to discuss their relationship and their clinical significance.
Methods: For 136 cases who were diagnosed of NSCLC, immunohistochemistry was used to detect protein expression of VEGF, EGFR and MMP-9 tumour and normal lung tissue specimens. Statistical analysis was performed on the relationship between protein expression of VEGF, EGFR and MMP-9 and clinico-pathological parameters and prognosis.
Results: Expression of VEGF and MMMP-9 was mostly in the cytoplasm, while EGFR wasfound in both cytoplasm and membranes. In NSCLCs, the positive rate of VEGF protein was 79.4% (108/136), for EGFR was 75.0% (102/136) and for MMP-9 was 68.4% (93/136), significantly greater than the normal tissue values of 16.0% (8/50), 12.0% (6/50) and 8.0% (4/50), respectively (P<0.01). Expression of VEGF, EGFR and MMP-9 was related to pathology grading, lymph node metastasis and clinical staging in NSCLC (P<0.01), while being independent of other clinicopathologic parameters (P>0.05). There was an obvious positive correlation among the expression of VEGF and EGFR (r=0.25; P<0.01), VEGF and MMP-9 (r=0.28; P<0.01), EGFR and MMP-9 (r=0.19; P<0.05) in NSCLCs.
Conclusions: Protein expression of VEGF, EGFR and MMP-9 is elevated higher in NSCLC, correlating with progression.