In the Cox regression model, univariate Cox regression indicates that the Age (p < 0.001), N stage (p < 0.001), M stage (p < 0.001), SMC4 (p = 0.036), pathologic stage (p < 0.001), menopause status (p < 0.001) and radiation therapy (p = 0.004) were correlated with the lousy prognosis of lung cancer (Table 2). Here, SMC4 is linked to lung cancer.