LRG1: an emerging player in disease pathogenesis

Area of Science:

• Biochemistry
• Molecular Biology
• Immunology

Background:

• Leucine-rich α-2 glycoprotein 1 (LRG1) is a secreted glycoprotein.
• LRG1 was initially identified for its role in ocular neovascularization.
• Emerging evidence suggests LRG1 involvement in cancer, diabetes, cardiovascular, neurological, and inflammatory diseases.

Purpose of the Study:

• To provide a comprehensive review of the LRG1 literature.
• To explore LRG1's roles in both health and disease.
• To discuss LRG1's potential as a biomarker and therapeutic target.

Main Methods:

• Literature review of published studies on LRG1.
• Analysis of LRG1 expression and function in various physiological and pathological contexts.
• Examination of LRG1's impact on cellular interactions and signaling pathways, particularly TGFβ.

Main Results:

• LRG1 is constitutively expressed but its absence shows no overt phenotype in mice, suggesting redundancy in homeostasis.
• LRG1 expression is induced by inflammatory stimuli and contributes to disease pathogenesis.
• LRG1 acts as a vasculopathic factor, disrupting vessel formation and promoting a hypoxic, immunosuppressive microenvironment.
• LRG1 modulates TGFβ signaling in various cell types, including epithelial, immune, mesenchymal, and cancer cells.
• Animal studies demonstrate that LRG1 inhibition attenuates disease progression.

Conclusions:

• LRG1 is a pleiotropic molecule with significant pathogenic functions.
• LRG1's role in innate immunity and tissue integrity is under investigation.
• LRG1 is a promising biomarker for diagnosis, prognosis, and monitoring of multiple conditions.
• LRG1 inhibition presents a potential therapeutic strategy, targeting its role in TGFβ signaling.
• Further research is needed to fully elucidate LRG1's functions and clinical applications.