Piero Picci

Sorafenib blocks tumour growth, angiogenesis and metastatic potential in preclinical models of osteosarcoma through a mechanism potentially involving the inhibition of ERK1/2, MCL-1 and ezrin pathways

BackgroundOsteosarcoma (OS) is the most common primary bone tumour in children and young adults. Despite improved prognosis, metastatic or relapsed OS remains largely incurable and no significant improvement has been observed in the last 20 years. Therefore, the search for alternative agents in OS is mandatory.ResultsWe investigated phospho-ERK 1/2, MCL-1, and phospho-Ezrin/Radixin/Moesin (P-ERM) as potential therapeutic targets in OS. Activation of these pathways was shown by immunohistochemistry in about 70% of cases and in all OS cell lines analyzed. Mutational analysis revealed no activating mutations in KRAS whereas BRAF gene was found to be mutated in 4/30 OS samples from patients. Based on these results we tested the multi-kinase inhibitor sorafenib (BAY 43-9006) in preclinical models of OS. Sorafenib inhibited OS cell line proliferation, induced apoptosis and downregulated P-ERK1/2, MCL-1, and P-ERM in a dose-dependent manner. The dephosphorylation of ERM was not due to ERK inhibition. The downregulation of MCL-1 led to an increase in apoptosis in OS cell lines. In chick embryo chorioallantoic membranes, OS supernatants induced angiogenesis, which was blocked by sorafenib and it was also shown that sorafenib reduced VEGF and MMP2 production. In addition, sorafenib treatment dramatically reduced tumour volume of OS xenografts and lung metastasis in SCID mice.ConclusionIn conclusion, ERK1/2, MCL-1 and ERM pathways are shown to be active in OS. Sorafenib is able to inhibit their signal transduction, both in vitro and in vivo, displaying anti-tumoural activity, anti-angiogenic effects, and reducing metastatic colony formation in lungs. These data support the testing of sorafenib as a potential therapeutic option in metastatic or relapsed OS patients unresponsive to standard treatments.

Atlas of musculoskeletal tumors and tumorlike lesions

Atlas of musculoskeletal tumors and tumorlike lesions : , Atlas of musculoskeletal tumors and tumorlike lesions : , کتابخانه دیجیتال جندی شاپور اهواز

Prognostic Relevance of CCN3 in Bone Sarcomas

Osteosarcomas and Ewing’s sarcoma (EWS) are aggressive malignant bone tumors. In both cases, prognostic markers are lacking. Presently, only clinical features are widely accepted as prognostic indicators. In this study we assessed the prognostic value of CCN3 (Nov), a matricellular protein that belong to the CCN family of regulatory proteins, whose members were shown to play crucial roles in bone formation. In osteosarcomas, CCN3 expression levels represent a useful tool to early identification of patients with different prognosis. In both osteosarcomas and Ewing’s sarcomas, the expression of a full length CCN3 protein was associated to a worse prognostic and a higher risk to developing metastasis. In Ewing’s tumors, the expression of a CCN3 protein lacking the internal VWC module was associated with reduced tumorigenic potential and better outcome.