According to the ELISA detection (Additional file 3), the CD5L concentration was ranging from 0.332 μg/ml to 0.907 μg/ml (median: 0.693μg/ml) in HCC serum and ranging from 0.384μg/ml to 0.802μg/ml (median: 0.626μg/ml) in normal serum. The gene discussed is CD5L; the disease is hepatocellular carcinoma.