Gene expression pattern of S100A8 -correlated genes and progression of two clusters. A: Gene expression patterns of S100A8 and its correlated genes. A total of 1,015 genes whose expression patterns are highly correlated with S100A8 were selected for cluster analysis (Pearson correlation test, P < 0.001, r < -0.3 or r > 0.3). Patients were divided into two groups: high S100A8 cluster (HSC) and low S100A8 cluster (LSC). B: Kaplan-Meier curves showing time to progression. The progression rate of HSC patients was significantly higher than that of LSC patients (log-rank test, P < 0.001).