HGF and hepatocellular carcinoma: Culturing HCC cells in IL-6- but not in HGF-containing media led to an approximately threefold increase in TG2 promoter activity, and the increased activity was suppressed by IL-6 receptor (IL6R) siRNAs (Figure 7A), supporting that TG2 was transcriptionally upregulated by the IL-6/STAT3 signaling during EMT.