Orosomucoid in liver diseases

Area of Science:

• Biochemistry
• Hepatology
• Oncology

Background:

• Orosomucoid (ORM), or alpha-1 acid glycoprotein (AGP), is an acute-phase protein synthesized in the liver, existing as ORM1 and ORM2 variants.
• ORM's biological effects vary with glycosylation patterns, making it a target for disease diagnosis and monitoring.
• ORM levels and glycosylation are implicated in liver conditions, including acute liver failure, fibrosis progression, and hepatocellular carcinoma (HCC).

Discussion:

• Decreased ORM levels can indicate HBV-associated acute liver failure (ALF), with ORM1 potentially aiding liver regeneration.
• Increased ORM and fucosylated forms correlate with fibrosis progression in viral hepatitis, suggesting noninvasive monitoring potential.
• Asialo-AGP (AsAGP) levels also correlate with fibrosis progression in chronic liver disease.

Key Insights:

• ORM enhances hepatocellular carcinoma (HCC) diagnosis when combined with other markers, particularly for AFP levels below 500 ng/mL.
• A unique trifucosylated glycan of ORM may serve as a marker for monitoring AFP-negative HCC.
• Reduced ORM2 expression in HCC correlates with aggressive disease and may indicate a tumor suppressor role, though further research is needed.

Outlook:

• ORM and its glycosylated variants are promising biomarkers for ALF identification, viral hepatitis fibrosis monitoring, and early HCC diagnosis.
• Further research into ORM expression in liver tissues is crucial to fully understand its role in carcinogenesis.
• Investigating ORM expression in borderline dysplastic nodules and hepatocellular adenomas could clarify its utility in histopathological differential diagnosis of HCC.