The promoting effect of adiponectin in hepatocellular carcinoma.

BACKGROUND AND OBJECTIVES

Adipokines may explain the newly established association of obesity with hepatocellular carcinoma (HCC). This study investigated if adiponectin levels in HCC patients differed from healthy controls and their potential effect in the development of HCC.

METHODS

Radioimmunoassay was used to determine serum adiponectin levels of 65 HCC patients and 165 healthy controls. The expressions of adiponectin protein in the tumor and adjacent non-tumor parts were examined by the immunoblotting method. Cell proliferation assays were used to assess the bioeffects of adiponectin in two human liver cancer cell lines.

RESULTS

Serum adiponectin levels were significantly higher in the HCC patients than the controls. Significant correlations of serum adiponectin levels with serum triglyceride levels and insulin resistance were found in the controls, but not in the HCC patients. In contrast, serum adiponectin levels significantly correlated with serum albumin and alkaline phosphatase levels in the HCC patients, but this trend was not observed in the controls. The expression pattern of adiponectin protein between the paired tumor and adjacent non-tumor tissues significantly correlated with tumor size. In vitro, adiponectin increased cell proliferation in a dose-dependent manner.

CONCLUSIONS

Increased adiponectin expressions were found in HCC and this increase might contribute to tumor growth.