GDF15 and hepatocellular carcinoma: Serum GDF15 levels were significantly increased in patients with HCC (6.66±0.67 ng/mL, p<0.0001) and cirrhosis (6.51±1.47 ng/mL, p<0.0001) compared with healthy controls (0.31±0.01 ng/mL), though the GDF15 levels in HBV and HCV carriers were moderately elevated (1.34±0.19 ng/mL and 2.13±0.53 ng/mL, respectively).