Hepatocellular carcinoma in viral and autoimmune liver diseases: Role of CD4+ CD25+ Foxp3+ regulatory T cells in the immune microenvironment

Figure 1 The hepatocellular carcinoma liver microenvironment is characterized by a large population of immune cells. Natural killer and CD8+ T cells exert antitumor effect by secreting interferon-γ, granzyme A, granzyme B and perforin, however they are mostly defective since these cells are suppressed by CD4+ CD25 regulatory T cell (Tregs). Additionally, tumor associated neutrophils (by secreting CCL17 and CCR4) and M2 tumor associated macrophages (by secreting interleukin-10) can induce CD4+ CD25+ Tregs thus supporting tumor growth and progression. NK: Natural killer; Treg: Regulatory T cell; IL: Interleukin; TGF-β: Transforming growth factor β; IFN: Interferon; HCC: Hepatocellular carcinoma.