CD8A and neoplasm: Among those are anti-inflammatory cytokines (e.g. transforming growth factor (TGF)-β, IL-6 or IL-10 [11]), inhibitory metabolic factors (e.g. prostaglandin E2 [12, 13] and extracellular adenosine [14]), interferon signaling defects [15] and downregulation of classical HLA class I molecules [16], which are required for attack by tumor-specific cytotoxic CD8+ T lymphocytes.