PCOLCE (procollagen C-endopeptidase enhancer) is a glycoprotein that primarily functions to enhance the proteolytic maturation of fibrillar procollagens by binding to the C-terminal propeptide of type I procollagen and stimulating procollagen C-proteinase activity 1. The protein exists as a 55-kDa form that is processed to 36- and 34-kDa forms while retaining full enhancing activity 1. PCOLCE localizes to extracellular structures and the extracellular matrix, where it promotes collagen deposition and potentially contributes to plaque stabilization through collagen fiber formation 23. In disease contexts, PCOLCE demonstrates significant oncogenic properties across multiple cancer types, with high expression correlating with poor prognosis in gliomas and promoting tumor growth through ERK signaling pathway activation 45. Additionally, PCOLCE serves as an autoantigen in rheumatoid arthritis, with anti-citrullinated PCOLCE antibodies showing diagnostic potential particularly in seronegative patients 6. The gene is highly expressed in collagen-rich tissues and maps to chromosome 7.3-q22 1. Beyond collagen metabolism, PCOLCE influences tumor immunity and may serve as a therapeutic target in various cancers 47.