The role of the proteoglycans in the pathogenesis of nephrogenic systemic fibrosis (NSF) is unclear. We assessed expression of decorin, versican, and transforming growth factor beta1 (TGF-beta1) in skin specimens of 10 patients with biopsy-proven NSF and different control groups. Real-time reverse transcription-polymerase chain reaction studies and immunohistochemical analysis were performed on full-thickness skin specimens. The messenger RNA (mRNA) and protein levels of decorin were significantly higher in the skin lesions of patients with NSF than in skin lesions of patients with systemic sclerosis, patients undergoing hemodialysis, and healthy subjects. The versican mRNA levels in NSF lesions differed significantly only from the levels in healthy subjects. TGF-beta1 mRNA expression was significantly overexpressed in NSF lesions compared with control skin specimens investigated. In NSF specimens, the mRNA expression of TGF-beta1 and decorin were highly correlated (r = 0.92). Our results suggest that decorin and TGF-beta1 may have a fundamental role in the pathogenesis of NSF. Conversely, versican seems less likely to be of pathogenetic significance in NSF.