Using data from the TIMER database, we revealed a significant correlation between the decreased expression of HLA-DPA1 and T cell exhaustion as well as markers of various immune cell types, including CD8+ T cells, T cells, B cells, monocytes, tumor-associated macrophages, macrophages, neutrophils, natural killer cells, dendritic cells, T helper cells, and Treg (Figure 12 and Table 3). This evidence concerns the gene CD8A and neoplasm.