Background: Augmenter of liver regeneration (ALR) is an important polypeptide in the process of liver regeneration. This study aimed to determine the expression level of ALR in different liver diseases and its significance.
Methods: We prepared murine polyclonal antibody against ALR protein from Balb/C mice and purified the IgG fraction, which specifically combined to ALR protein as shown by Western blotting. Serum ALR levels in patients with hepatocellular carcinoma (HCC), hepatic failure (HF), chronic hepatitis B, and healthy persons were compared by ELISA. ALR mRNA expression levels in liver tissues in some of these patients were also compared by real-time RT-PCR. Immunohistochemical analysis was carried out on HF and HCC liver tissues.
Results: Different serum ALR levels foreshowed completely different prognoses in 18 HF patients. Higher ALR levels were noted in 6 improved patients (1613.5+/-369.6 pmol/ml) than in 12 deteriorating patients (462.3+/-235.8 pmol/ml). Similar levels were found in 20 HCC patients (917.9+/-332.7 pmol/ml), 24 chronic hepatitis B patients (969.2+/-332.5 pmol/ml) and 10 healthy persons (806.9+/-240.8 pmol/ml). ALR mRNA levels in HCC liver tissues [10E6.24 (1.74X10(6)) copies/μl] were much higher than in those of HF patients receiving orthotopic liver transplantation [10E3.45 (2.82X10(3)) copies/μl] or in healthy liver tissues [10E4.31 (2.04X10(4)) copies/μl]. In immunohistochemical analysis, positive immunostaining in HCC liver tissue was more intense than that in HF liver tissue.
Conclusion: Serum ALR level is helpful in estimating the survival time of patients with HF, and ALR may play an important role in hepatocarcinogenesis.