We further analyzed cell–cell interaction in tumor tissues and an interesting finding was that TNFRSF14, a co-stimulatory molecule (22), interacted with MIF widely existing in all major immune cell types and malignant cells of the liver, indicating that TNFRSF14/MIF signaling may be a promising target of immunotherapy in HCC (Figure 3F). Here, MIF is linked to hepatocellular carcinoma.