Phenotypic and functional analysis of lymphocytes infiltrating osteolytic tumors: use as a possible therapeutic approach of osteosarcoma

BACKGROUND: Osteosarcoma is the most common type of primary bone tumor. The use of aggressive chemotherapy has drastically improved the prognosis of the patients with non-metastatic osteosarcomas, however the prognosis of the patients with metastasis is still very poor. Then, new and more effective treatments for curing osteosarcoma, such as immunotherapy are needed. Tumor-infiltrating lymphocytes (TIL) have been involved in the control of tumor development and already assessed with success for the treatment of several cancers including melanoma. While TIL represent a fascinating therapeutic approach in numerous malignant pathologies, there is few report concerning adult bone-associated tumors including osteosarcoma. METHODS: Human TIL were isolated and characterized (phenotype, lytic activity) from twenty-seven patients with bone-associated tumors (osteosarcoma, Ewing's sarcoma, giant cell tumor, chondrosarcoma, plasmocytoma and bone metastases). Similar experiments were performed using rat osteosarcoma model. RESULTS: While TIL with a main CD4(+ )profile were easily isolated from most of the tumor samples, only TIL extracted from osteosarcoma were cytotoxic against allogeneic tumor cells. In all cases, TIL lytic activity was significantly higher compared to autologous peripheral blood leukocytes. Similar data were observed in rat osteosarcoma model where TIL were characterized by a main CD4(+ )profile and high lytic activity against allogeneic and autologous tumor cells. Moreover, rat TIL expansion was not accompanied by refractoriness to further activation stimulus mainly by tumor antigens. CONCLUSION: These results demonstrated that TIL therapy could be a very efficient strategy for the treatment of adult osteosarcoma

Biomaterials: the new frontiers in spine surgery.

Journal Articleinfo:eu-repo/semantics/publishe

Potential synergies between matrix proteins and soluble factors on resorption and proteinase activities of rabbit bone cells

Human growth hormone (GH) has recently been found to stimulate osteoclastic resorption, cysteineproteinase and metalloproteinase activities (MMP-2 and MMP-9) in vitro via insulin-like growth factor-1 (IGF-1) produced by stromal cells. The present study investigated the effects of two extracellular matrix components (vitronectin and type-1 collagen) on hGHand hIGF-1-stimulated osteoclastic resorption and proteinase activities in a rabbit bone cell model. After 4 days of rabbit bone cell culture on dentin slices with vitronectin coating, hGH and hIGF-1 stimulated bone resorption and hIGF-1 upmodulated cysteine-proteinase activities. MMP-2 expression (but not resorption, cathepsin or MMP-9 activities) was upmodulated by hGH and hIGF-1 on dentin slices coated with type 1 collagen as compared to those without coating. Then, vitronectin was synergistic with hIGF-1 in the regulation of cysteine-proteinase production whereas collagen showed synergy with hGH and hIGF-1 in the regulation of MMP-2 production. Anti-αvβ3 totally abolished the effects of hGH and hIGF-1 on metalloproteinase release, but had no influence on cathepsin release. The results suggest that cysteine-proteinase modulation is not mediated by αvβ3 integrin (strongly expressed on osteoclastic surface) whereas the resorption process and metalloproteinase modulation are clearly'mediated by this integrin. Our finding about the collagen coating also suggests that hGH- and hIGF-1-stimulated MMP-2 activity are mediated, along with αvβ3 integrin, by another adhesion molecule

Bone remodelling and tumour grade modifications induced by interactions between bone and swarm rat chondrosarcoma

Chondrosarcoma is currently defined as a malignant cartilage tumour arising de novo or within a pre-existing benign cartilage tumour. Chondrosarcoma can be surgically resected, but all grades have significant rates of local recurrence. The purpose of the present study was to develop an animal intraosseous chondrosarcoma model simulating the progression of human chondrosarcoma and elucidating its behaviour and biology. An intraosseous Swarm rat model was designed to assess interactions between bone and chondrosarcoma. A comparison of tumour grading was carried out according to transplantation site. The effects of chondrosarcoma cells (SRC cells) on the mineralisation capacities of osteoblasts and on osteoclast differentiation were studied in relation to modifications observed in vivo at the cellular level. Transplantation of Swarm rat chondrosarcoma within bone marrow or contiguous to induced periosteal lesions led to extensive bone remodelling with trabecular bone rarefaction and periosteal apposition. Transplantation in close contact to bone but without any periosteal lesion had no effect on bone, suggesting that bone healing factors interact with tumour development. With the intramedullary model, the development of tumours of different grade confirms that bone environment is an important factor in malignancy. A decrease of bone nodule formation was noted after cocultures of SRC cells with rat bone marrow, but there was no modification of osteoclast differentiation after cultures of total rabbit bone cells with SRC cells. These data reveal the importance of interactions between bone environment and tumour in inducing bone remodelling and variations in tumour malignancy

Influence of metal ion solutions on rabbit osteoclast activities in vitro

The purpose of the present study was to compare the effects of various metal ions (aluminium, chromium, cobalt, gold, iron, strontium, titanium and vanadium) on rabbit osteoclast activities, with respect to their number, size, resorptive capacity and their capacity to release proteinases. Marked heterogeneous osteoclastic behaviour was observed early in culture with metal ions (24 h) in term of resorption parameters. In contrast, protease activities (cysteine-proteinase and metalloproteinase activities) were not modulated in our culture conditions. Aluminium, iron, gold and titanium reduced the number of osteoclasts significantly. Aluminium and gold had no effect on osteoclastmediated resorption on dentin-slices, although aluminium induced a greater number of very small lacunae. Titanium reduced only the mean surface area per lacunae, cobalt reduced the mean surface area of lacunae and increased their number, and iron reduced both parameters. Strontium had no effect on osteoclast formation and on total dentin slice surface resorbed. However, strontium increased the number of small lacunae formed on dentin-slices by osteoclasts. Chromium had no effect on osteoclast activities. These findings indicate that metal ions induce very early effects on osteoclasts, which can contribute to periprosthetic pathologies via different cellular mechanisms