The expression of CBX4 was positively associated with all of the assessed immune cells in both RCC subtypes (in details, for ccRCC: CD4+ T cells (ρ = 0.252, p = 3.98−8), neutrophils (ρ = 0.288, p = 2.79−10), dendritic cells (ρ = 0.243, p = 1.23−7); for pRCC: B cell (ρ = 0.211, p = 6.61−4), CD4+ T cells (ρ = 0.158, p = 1.11−2), CD8+ T cells (ρ = 0.256, p = 3.07−5), neutrophils (ρ = 0.327, p = 7.74−8) and dendritic cells (ρ = 0.328, p = 6.85−8). The gene discussed is CD4; the disease is renal cell carcinoma.