Downregulated RhoBTB2 expression contributes to poor outcome in osteosarcoma patients.

Purpose: Osteosarcoma is a malignant bone tumor. RhoBTB2 protein participated in various cellular activities and influenced pathways responsible for cell cycle and apoptosis. To address its potential as a therapeutic target for osteosarcoma, this study investigated the effect of RhoBTB2 expression on osteosarcoma tissue and cell.

Materials And Methods: Real-time PCR and immunohistochemistry analysis were performed to evaluate the level of RhoBTB2 mRNA and protein in 121 osteosarcoma specimens. The relationship of RhoBTB2 expression with clinicopathological parameters of osteosarcoma patients was analyzed using Chi-square test. In addition, a plasmid expressing the RhoBTB2 gene was transfected into human osteosarcoma (HOS) cell using Lipofectamine 2000, and the effects of RhoBTB2 on HOS cell were investigated using 3-(4,5-dimethylthiazolyl)-2,5-diphenyltetrazoliumbromide assay and flow cytometry.

Results: This study reports that RhoBTB2 protein is weakly expressed in osteosarcoma specimens, but highly in normal parts of specimens. RhoBTB2 expression is significantly associated with primary location and local recurrence of osteosarcoma. Overexpression of RhoBTB2 results in significant G1 phase arrest and apoptosis in HOS cell.

Conclusion: Taken together, we identified the role RhoBTB2 in osteosarcoma tissue and cell. The results might not only be of relevance for diagnosis and prognosis, but potentially also provide a novel target for osteosarcoma therapies.