In addition, the expression of PPP1BC, PPP1CC and RAC1 was correlated with the tumor stage (P < 0.05) (Supplementary Figure 4C–4D); the expression of PPP1CC and SPP1 was correlated with age (P < 0.05) (Supplementary Figure 4A); the expression of PPP1CB was correlated with gender (P < 0.05) (Supplementary Figure 4B). The gene discussed is SPP1; the disease is neoplasm.