For example, hepatocellular carcinoma (HCC)‐derived exosomes highly express HMGB1, and HMGB1 strongly induces B cells to express TIM‐1 through the TLR2/4‐MAPK pathway.[49] These TIM‐1+ B cells correlate with poor clinical prognosis in HCC. Here, TLR2 is linked to hepatocellular carcinoma.