Figure 4. Further bioinformatics analysis of S100A9 in glioma. (A) Comparison of the distribution of samples in TCGA, CGGA1, and CGGA2 cohorts before and after expression profile merging. (B) Presentation of the cross genes in TCGA, CGGA1, and CGGA2 cohorts. (C) The volcano plot displayed the DEGs between high- and low-expression groups of S100A9. (D) The heat map showed the relative expression levels of the top 40 genes with the most significant difference according to the median expression value of S100A9. (E, F) The enrichment analysis of KEGG pathways (E) and the terms of GO-BP (F) based on the DEGs. (G, H) The gene sets involved in tumor malignant progression (G), immune and inflammatory response (H) were enriched through differential expression levels of S100A9.