Cellular communication network factor 1 (CCN1)

Cellular communication network factor 1 (CCN1, historically CYR61) is a secreted, cysteine-rich matricellular protein of the CCN family that associates with the extracellular matrix and signals through multiple integrins and heparan sulfate proteoglycans (notably syndecan-4). CCN1 contains an N‑terminal signal peptide and four conserved modules—IGFBP, vWC, TSP‑1, and a C‑terminal cystine-knot (CT)—that mediate binding to integrins (e.g., αvβ3, α6β1, αIIbβ3, αMβ2, αDβ2) and growth factor pathways, enabling regulation of adhesion, migration, proliferation, senescence, apoptosis, angiogenesis, wound healing, and matrix remodeling. It exhibits context-dependent roles in disease: it participates in tumor microenvironment signaling with both tumor-promoting and tumor-suppressive activities depending on cancer type and microenvironment; it is implicated in fibrotic and inflammatory remodeling, with contrasting effects across organs (notably liver); and it contributes to retinal vascular leakage in diabetic retinopathy. While CCN1 is considered a potential therapeutic target due to its extracellular accessibility and central role in integrin-mediated signaling, no approved drugs currently target CCN1 directly; experimental approaches include neutralizing antibodies or peptides that disrupt CCN1–integrin/HSPG interactions.

Other names

CCN1CYR61Cysteine-rich angiogenic inducer 61Cysteine-rich protein 61IGFBP-rP4insulin-like growth factor binding protein-related protein 4CTGF family member 1

For experimental agents: neutralization of CCN1–integrin/HSPG interactions to reduce angiogenesis, inflammation, or fibrosis; or modulation of downstream signaling from integrins (e.g., αvβ3, α6β1) and syndecan-4–dependent pathways. Note: No approved MOA for marketed drugs directly against CCN1 identified in cited sources.