Metastatic AJCC stage N2 patients with high levels of PLK1 and TNFAIP6 had lower survival rates than similar patients with low PLK1 and TNFAIP6, suggesting that the high expression of both TNFAIP6 and PLK1 is a negative marker for survival among primary and metastatic NSCLC patients. Here, PLK1 is linked to non-small cell lung carcinoma.