Recent studies have established that metabolic restrains, such as glucose restriction, impair the activities of effector T cells in TME.69, 83 In the same context, the remarkable expansion of activated Treg cells, which is characterized by the expression of CD4, CD25, cytotoxic T lymphocyte‐associated protein 4 (CTLA‐4) and forkhead box P3 (FoxP3) in tumour tissues, has been described in both mice and humans, thereby contributing to the suppression of protective anti‐tumour immunity.48, 84 CD8+ T cells are the most important executors of the anti‐tumour adaptive immunity, including HCC. Here, CD4 is linked to hepatocellular carcinoma.