COMP, also known as cartilage oligomeric matrix protein, is an extracellular matrix (ECM) glycoprotein. It is critical for collagen assembly and ECM stability, and binds to types II and IX collagens [4]. COMP has been associated with multiple fibrotic conditions and is involved in regulating the TGF-β signaling pathway [2].

In pancreatic fibrosis, COMP was up-regulated in fibrotic tissues of chronic pancreatitis (CP) patients. Knockdown of COMP inhibited the proliferation and migration of pancreatic stellate cells (PSCs), while recombinant human COMP (rCOMP) promoted their proliferation and activation through the CD36-ERK/AKT signaling pathway [1]. In atrial fibrillation, silencing COMP inhibited the activation of the TGF-β pathway in AF cells, and COMP could improve Ang-II-induced AF via this pathway [2]. In lung transplantation, higher mean COMP levels early after transplantation were associated with the development of restrictive allograft syndrome (RAS), suggesting it could be a biomarker [3]. In pseudoachondroplasia, mutations in COMP cause abnormal chondrocyte function due to retention of COMP and type IX collagen in the endoplasmic reticulum [4].

In conclusion, COMP plays essential roles in collagen-related functions and is involved in multiple disease conditions such as fibrosis, atrial fibrillation, and some genetic disorders. Studies, especially those using gene-knockdown approaches, have revealed its functions in specific biological processes related to these diseases, providing potential therapeutic directions, like interfering with COMP expression or its interactions in relevant cells for treating CP [1].