BACKGROUND:?Transforming growth factor-β (TGF-β) plays an important role in the regulation of cell growth and differentiation, angiogenesis, extracellular matrix formation, immunosuppression and cancer development. In this study, we investigated the levels of TGF-β1 and TGF-β1 mRNA expression, their relationship with HBV replication, and their diagnostic value for hepatocellular carcinoma (HCC). METHODS:?Total RNAs were extracted from HCC samples and matched non-tumor tissues, and from peripheral blood mononuclear cells in HCC patients. TGF-β1 mRNA was ampliifed by RT-PCR and conifrmed by DNA sequencing. The distribution of TGF-β1 expression was assessed by immunohistochemistry. The clinical characteristics were analyzed between TGF-β1 and HBV replication. The diagnostic value of circulating TGF-β1 and TGF-β1 mRNA levels were investigated in HCC patients. RESULTS:?The incidence of hepatic TGF-β1 expression was 83.3%in HCC samples, 43.3%in the surrounding tissues, 94.7%in the HBV DNA-positive group, and 63.6%in the HBV DNA-negative group. Liver TGF-β1 expression was associated with the degree of HCC differentiation and the status of HBV replication, but not with the size or number of tumors. Circulating TGF-β1 level and incidence of TGF-β1 mRNA were signiifcantly higher in the HCC groupthan in any group of patients with benign liver disease, with a higher sensitivity of 89.5%and a speciifcity of 94.0%for HCC diagnosis when circulating TGF-β1 levels were>1.2 μg/L. No signiifcant correlation was found between TGF-β1 expression and AFP level or tumor size. Combining TGF-β1 level and serum AFP raised the detection rate to 97.4%. CONCLUSIONS:?Abnormal expression of hepatic TGF-β1 is associated with the degree of HCC differentiation and HBV replication. Both circulating TGF-β1 and TGF-β1 mRNA can be used as sensitive biomarkers for the diagnosis and prognosis of HBV-induced HCC.