Up-regulation of MDC15 (metargidin) messenger RNA in human osteoarthritic cartilage

Objective. The aim of the study was to investigate the messenger RNA (mRNA) expression of the disintegrin metalloproteinase MDC15 (metargidin, or ADAM -15) in normal and osteoarthritic (OA) articular cartilage. Methods, In situ hybridization experiments and reverse transcription-polyme rase chain reaction (RT-PCR) were performed on tissue samples of adult norm al and OA articular cartilage. Results. MDC15 mRNA could be detected in normal articular cartilage by RT-P CR using tissue-extracted total RNA as a template. However, the mRNA level remained below the sensitivity of in situ hybridization, In contrast, in si tu hybridizations of OA cartilage revealed an intense staining with the MDC 15-specific riboprobes. The extension of the analysis to chondrosarcomas sh owed a strong up-regulation of MDC15 mRNA in these malignant transformed ce lls. Conclusion. Our results demonstrate a markedly strong up-regulation of MDC1 5 in adult OA and neoplastic cartilage compared,vith adult normal articular cartilage, indicating a potential role of the disintegrin metalloproteinas e in cartilage remodeling.