The ratio of CD8+ T cells to regulatory T (Treg) cells in the tumor microenvironment (TME) is also an important factor for predicting prognosis and clinical efficacies.20 21 Furthermore, anti-CTLA-4 may be effective in some patients with lower response rates to programmed death-1 (PD-1) blockade. The gene discussed is CD8A; the disease is neoplasm.