CD4 and neoplasm: To explore the complex tumor microenvironment of BRCC, with cell types including endothelial cells, fibroblasts, and immune cells (CD4+ T cells, CD8+ T cells, B cells, natural killer cells, and bone marrow cells), we calculated the expression levels of marker genes associated with each cell type in each cell cluster and thus inferred the distribution of each cell subtype of BRCC in its various cell clusters.