Musculoskeletal oncology--advances in cytogenetics and molecular genetics and their clinical implications

Achievements during the Bone and Joint Decade 2000-2010

Musculoskeletal diseases continue to produce major disability around the world. Advances in therapy - particularly for the inflammatory diseases - have the potential to eradicate the inflammation and thus prevent joint destruction. Surgical advances include minimally invasive and computer-assisted robotic surgery, and advances in arthroscopic surgery. The development of new musculoskeletal tissues - tendons, cartilage and bone using nanotechnology and stem cells - has the potential to revolutionise the way we approach these chronic destructive diseases as well as major trauma. With the rapid increase in these conditions with an ageing population, new models of care will need to be developed to ensure that the right care is delivered at the right time by the most appropriately trained health professional and at a reasonable cost. The Bone and Joint Decade has played a significant role in focussing researchers, clinicians and health educators on these diseases and also in drawing them to the attention of Governments around the globe. While there is still much to be done, the journey has commenced and will continue into the future with education, research and service delivery into these important conditions being further enhanced.

Disseminated osteosarcoma arising in the pelvis after total hip arthroplasty

The development locally of a malignant neoplasm after total hip arthroplasty is rare but increasingly recognized. Its significance is unclear. The association could be fortuitous. If not, the rarity of the complication argues that constitutional factors are likely to be important in pathogenesis. We describe a case of disseminated osteosarcoma of the hip developing 6.5 years after total hip arthroplasty and review the related literature.

A PCR-ELISA assay for the detection of disseminated osteosarcoma cells in a mouse metastatic model

Circulating tumor cells in the blood play a central role in the metastatic process. There have been no reports describing the relationship between lung metastasis and circulating osteosarcoma cells. We developed a system with a polymerase chain reaction assay based on an enzyme-linked immunosorbent assay (PCR-ELISA) to detect circulating osteosarcoma cells in a mouse metastatic model. Osf2/Cbfa1, hereafter called Osf2, a member of the runt family of transcription factors, was used as a target gene. One splicing variant of Osf2 mRNA was identified and its expression was restricted to the bones and osteosarcomas. The amount of the splicing variant of Osf2 mRNA was significantly higher in the blood of mice with metastasis than in the blood of the control group. The PCR-ELISA using Osf2 mRNA is a potential method to detect circulating osteosarcoma cells in peripheral blood.

Collagenase specificity in chondrosarcoma metastasis

The treatment of some mesenchymal malignancies has made significant gains over the past few decades with the development of effective systemic therapies. In contrast, the treatment of chondrosarcoma has been limited to surgical resection, with the most significant prognostic indicators being surgical margins and histologic grade. We have reported that MMP-1/TIMP-1 gene expression serves to prognosticate for tumor recurrence in this group of patients. This led to the hypothesis that collagenase activity facilitates cell egression from the cartilaginous matrix. In the current study we examine the specificity of collagenase gene expression in archival human chondrosarcoma samples using semi-quantitative PCR. Messenger RNA was affinity extracted and subject to reverse transcription. The subsequent cDNA was amplified using novel primers and quantitated by densitometry. Ratios of gene expression were constructed and compared to disease-free survival. The data demonstrate that the significance of the MMP-1/TIMP-1 ratio as a predictor of recurrence is confirmed with a larger number of patients. Neutrophil collagenase or MMP-8 was observed in only 5 of 29 samples. Collagenase-3 or MMP-13 was observed in all samples but the level did not correlate with disease-free survival. Since the collagenases have similar activity for fibrillar collagens and cleave the peptide in the same location, post-transcriptional regulatory mechanisms may account for the observed specificity. The determination of the MMP-1/TIMP-1 gene expression ratio not only serves to identify those patients at risk for recurrence but may also serve as a novel therapeutic avenue as an adjunct to surgical resection.