Figure 3G and H visualized the top 20 genes with the highest alteration frequency and showed that Cluster 2 had a higher overall gene mutation frequency than Cluster 1. The Cluster 2 subtype harbored a higher tumor mutation burden (TMB) score than Cluster 1 (Fig. 3I). Previous research has shown that a high TMB is linked with higher numbers of potentially immunogenic neoantigens (47) and the activation of infiltrating CD8+ T cells that may facilitate anti-tumor immune responses (48). The gene discussed is CD8A; the disease is neoplasm.