To further validate the GSEA results, we then detected the protein expression of cell cycle (PCNA and CDC25A), cell apoptosis (Bcl-2 and Bax) and metastasis (MMP-2, MMP-9, Snail and E-cadherin) in NSCLC cells (Figure 6A). The gene discussed is MMP9; the disease is non-small cell lung carcinoma.