CD4 and cancer: Due to the fact that regulatory T cells (Tregs) are known to be increased in cancer patients [31,32,33], we also evaluated Tregs (CD3+ CD4+ Foxp3+) in all the tissues of HCC patients and, indeed, observed an increased frequency in the PBMC of HCC patients (4.88 ± 0.97), as compared to healthy controls (2.28 ± 0.44) (Figure 3b and Table 3).