RESUMEN
DNA microarray analysis was used to investigate the molecular phenotype of one of the first human chondrocyte cell lines, C-20/A4, derived from juvenile costal chondrocytes by immortalization with origin-defective simian virus 40 large T antigen. Clontech Human Cancer Arrays 1.2 and quantitative PCR were used to examine gene expression profiles of C-20/A4 cells cultured in the presence of serum in monolayer and alginate beads. In monolayer cultures, genes involved in cell proliferation were strongly upregulated compared to those expressed by human adult articular chondrocytes in primary culture. Of the cell cycle-regulated genes, only two, the CDK regulatory subunit and histone H4, were downregulated after culture in alginate beads, consistent with the ability of these cells to proliferate in suspension culture. In contrast, the expression of several genes that are involved in pericellular matrix formation, including MMP-14, COL6A1, fibronectin, biglycan and decorin, was upregulated when the C-20/A4 cells were transferred to suspension culture in alginate. Also, nexin-1, vimentin, and IGFBP-3, which are known to be expressed by primary chondrocytes, were differentially expressed in our study. Consistent with the proliferative phenotype of this cell line, few genes involved in matrix synthesis and turnover were highly expressed in the presence of serum. These results indicate that immortalized chondrocyte cell lines, rather than substituting for primary chondrocytes, may serve as models for extending findings on chondrocyte function not achievable by the use of primary chondrocytes.
Asunto(s)
Cartílago Articular/citología , Técnicas de Cultivo de Célula/métodos , Condrocitos/citología , Condrocitos/fisiología , Expresión Génica , Anciano , Alginatos , Línea Celular , Cartilla de ADN/química , ADN Complementario/análisis , Femenino , Ácido Glucurónico , Ácidos Hexurónicos , Humanos , Masculino , Persona de Mediana Edad , Análisis de Secuencia por Matrices de Oligonucleótidos , Fenotipo , Reacción en Cadena de la Polimerasa , ARN/aislamiento & purificaciónRESUMEN
INTRODUCTION: Giant cell tumor of the distal fibula is a very rare condition. The treatment of advanced tumors at this location can be challenging and has been described in the literature only in single cases. MATERIALS AND METHODS: We report on a patient with a stage III giant cell tumor, according to the classification of Campanacci, of the distal fibula after en bloc resection and distal fibula reconstruction with a long bone graft from the iliac crest in a second procedure. The syndesmosis was reconstructed with a periosteal flap, the capsule and ligaments with local scar tissue. RESULTS: Fifteen years after the initial treatment the patient is free of local recurrence and demonstrates an excellent clinical outcome without any signs of instability, loss of function or osteoarthritis of the ankle joint. CONCLUSION: We suggest the method to be worthwhile for treatment of this uncommon lesion in terms of recurrence and functional outcome.