HAVCR2 and cancer: TFH cells in cancer correlate with increased survival in melanoma [39] and in breast cancer, with extensive immune cell infiltration and increased interferon γ, CD8+ cells, and B cells [40,41]; some studies, however, suggest that TFH cells may increase TGF-β and IL-10 as well as PD1+/TIM3+ cells, which could be indicative of dysfunctional CD8+ cells [42,43].