CCN3 emerges as a multifaceted driver in Rheumatoid Arthritis pathogenesis, showing promise as a therapeutic target

Rheumatoid arthritis (RA) is a chronic autoimmune disease marked by persistent synovial inflammation, progressive joint destruction, and bone damage. Despite advancements in disease-modifying antirheumatic drugs (DMARDs), significant unmet clinical needs persist due to incomplete efficacy and safety concerns, driving the search for innovative therapeutic targets. Cellular communication network factor 3 (CCN3), a matricellular CCN family protein, is notably low in normal synovium but significantly elevated in RA synovium and circulation, correlating with disease activity and specific biomarkers like anti-cyclic citrullinated peptide (anti-CCP) antibodies and IL-6.

This comprehensive review synthesized findings from existing literature to examine the expression patterns, functional mechanisms, and signaling pathways associated with CCN3 in Rheumatoid Arthritis. The authors systematically analyzed published research to explore CCN3's role in inflammatory-cell recruitment, fibroblast-like synoviocyte (FLS) activation and senescence, extracellular matrix (ECM) remodeling, cartilage degeneration, and osteoclastogenesis. The review also delved into the mechanistic interactions of CCN3 with various RA-relevant signaling networks, including NF-κB, Wnt/β-catenin, BMP/Smad, PI3K/Akt/mTOR, IL-6/JAK/STAT, Notch, and MAPK pathways, to assess its therapeutic potential.

The review highlights that CCN3 is consistently found at elevated levels in RA synovium and circulation, where its concentration directly correlates with disease activity, anti-CCP antibody titers, and IL-6 levels. CCN3's multifaceted role in RA pathogenesis includes promoting inflammatory-cell recruitment, activating and inducing senescence in fibroblast-like synoviocytes (FLS), and contributing to extracellular matrix (ECM) remodeling. Furthermore, CCN3 is implicated in cartilage degeneration and osteoclastogenesis, key processes in joint destruction. Mechanistically, CCN3 interacts with several crucial RA-relevant signaling pathways, including NF-κB, Wnt/β-catenin, BMP/Smad, PI3K/Akt/mTOR, IL-6/JAK/STAT, Notch, and MAPK networks, suggesting its broad influence on cellular processes. This extensive review consolidates evidence supporting CCN3 as a significant contributor to RA pathology.

The consistent elevation of CCN3 in RA synovium and its strong correlation with disease activity and IL-6 levels positions it as a promising novel therapeutic target for Rheumatoid Arthritis.