1. Department of Pathology; Leiden University Medical Center; Leiden The Netherlands
2. Department of Molecular Cell Biology; Leiden University Medical Center; Leiden The Netherlands
3. Department of Pathology; Hospital Vall D'hebron; Barcelona Spain
4. Laboratory of Experimental Oncology; Orthopaedic Rizzoli Institute; Bologna Italy
5. Department of Pathology; University of Copenhagen; Denmark
6. Department of Orthopedic Surgery; Leiden University Medical Center; Leiden The Netherlands