Our study highlights the reported variant to be a trivial factor and possibly other confounding factors may regulate STAT4 expression during HCC development.
In the gene expression analyses, although no significant differences in mRNA expression of nearby genes according to genotypes were detected, a significantly decreased mRNA expression in HCC subjects was observed in STAT4, HLA-DQA1, and HLA-DQB1.
Recent studies demonstrated that single nucleotide polymorphisms (SNPs) rs2293152 in signal transducer and activator of transcription 3 (STAT3) and rs7574865 in signal transducer and activator of transcription 4 (STAT4) are associated with chronic hepatitis B (CHB)-related HCC in the Chinese population.
We observed that the STAT4 (2q32.2-q32.3) at rs7574865 (P=1.17×10(-3), OR=0.79) and EFCAB11 (14q32.11) at rs8013403 (P=1.54×10(-3), OR=0.80) were significantly associated with HCC in this study.
STAT4 gene polymorphism has been shown to be associated with the antiviral response in chronic hepatitis C and drug-induced liver injury (DILI), primary biliary cirrhosis (PBC), HCV-associated liver fibrosis and in hepatocellular carcinoma (HCC).
Meta-analysis of the included studies revealed that STAT4rs7574865 polymorphism contributed to the risk of HCC under all four genetic models, consisting of the allelic model (G vs. T: odds ratio [OR], 1.25; 95% confidence interval [CI], 1.19-1.30), the dominant effect model (GG + GT vs. TT: OR, 1.52; 95% CI, 1.26-1.84), the recessive effect model (GG vs. GT + TT: OR, 1.35; 95% CI, 1.21-1.50), and the co-dominant effect model (GG vs.. TT: OR, 1.72; 95% CI, 1.42-2.10) comparisons.
Recently, a genome-wide association study (GWAS)-identified polymorphism in the STAT4 gene that contributes to the risk for hepatocellular carcinoma (HCC) was shown to be associated with the full spectrum of hepatitis B virus (HBV) outcomes in Asian patients.