Augmenter of Liver Regeneration Monoclonal Antibody Promotes Apoptosis of Hepatocellular Carcinoma Cells

Background and Aims: Hepatocellular carcinoma (HCC) is one of the most common types of cancer, often resulting in death. Augmenter of liver regeneration (ALR), a widely expressed multifunctional protein, has roles in liver disease. In our previous study, we reported that ALR knockdown inhibited cell proliferation and promoted cell death. However, there is no study on the roles of ALR in HCC. Methods: We used in vitro and in vivo models to investigate the effects of ALR in HCC as well as its mechanism of action. We produced and characterized a human ALR-specific monoclonal antibody (mAb) and investigated the effects of the mAb in HCC cells. Results: The purified ALR-specific mAb matched the predicted molecular weight of IgG heavy and light chains. Thereafter, we used the ALR-specific mAb as a therapeutic strategy to suppress tumor growth in nude mice. Additionally, we assessed the proliferation and viability of three HCC cell lines, Hep G2, Huh7, and MHC97-H, treated with the ALR-specific mAb. Compared with controls, tumor growth was inhibited in mice treated with the ALR-specific mAb at 5 mg/kg, as shown by hematoxylin and eosin staining and terminal deoxynucleotidyl transferase dUTP nick end labeling. Simultaneous treatment with the ALR-specific mAb and adriamycin promoted apoptosis, whereas treatment with the ALR-specific mAb alone inhibited cell proliferation. Conclusions: The ALR- specific mAb might be a novel therapy for HCC by blocking extracellular ALR.