Figure 1.

IL-6/STAT3 pathway was hyperactivated in HCC tissues and related with up-regulation of HIF-1α positively. A. IL-6 protein expression was found predominantly in the cytoplasm of HCC cells and positive in samples from 82 of 86 HCCs (95.3%) by IHC assay. Mann-Whitney U test confirmed that there was more IL-6 expression in HCC tissues than adjacent liver tissues. B. p-STAT3 protein was found located mainly in nucleus of tumor cells, while there was also detectable p-STAT3 protein in cytoplasm of tumor cells as assessed by IHC. Mann-Whitney U test also demonstrated that the expression of p-STAT3 in tumor samples was significantly higher than one in adjacent liver samples. C. By Log-rank test, comparison of survival curves revealed that HCCs from High p-STAT3 group suffered from remarkably worse prognosis after TACE than those from Low p-STAT3 group. D. The analysis of data from the Cancer Genome Atlas (TCGA) database displayed that there was apparently correlation between STAT3 mRNA and HIF-1α mRNA in 371 HCC samples (Fig.1D, r-value=0.393 p-value=3.6e-15 T-value=8.215). E. IHC staining assay exhibited that HIF-1α protein located in both cytoplasm and nucleus of tumor cells and Spearman rank correlation analysis that there was remarkably positive association between p-STAT3 and HIF-1α in HCC tissues.