STAT3 and hepatocellular carcinoma: Yu-Ping-Feng-San attenuates the activation of the thymic stromal lymphopoietin-signal transducer and activator of transcription 3 (TSLP-STAT3) signaling pathway by inhibiting the immune-related factor TSLP, thereby inhibiting the formation of hepatic microvessels and exerting an anti-HCC effect (Yuan et al., 2019).