STAT3 and hepatocellular carcinoma: It has been also demonstrated that cancer-associated fibroblasts infiltrating HCC promote the activation and survival of TANs, which is reflected by an increased expression of CD66b, PD-L1, IL-8, TNF, and CCL2, but decreased expression of CD62L through an IL-6 signal transducer and activator of transcription-3 (STAT3)-PD-L1 signaling cascade [48].