Overexpression of RBM10 induces osteosarcoma cell apoptosis and inhibits cell proliferation and migration.

Osteosarcoma is the most common malignant bone tumor with high incidence in adolescence and poor prognosis. RBM10, a member of RBPs, was reported to be a tumor suppressor in many kinds of cancers. However, the roles of RBM10 in osteosarcoma remain unknown. In this study, we found that overexpression of RBM10 decreased osteosarcoma cell proliferation and colony formation in soft agar, and inhibited osteosarcoma cell migration and invasion. Our results also revealed that RBM10 overexpression induced osteosarcoma cell apoptosis via the inhibition of Bcl-2, the activation of caspase-3, and the transcription and production of TNF-α. Our results indicated that RBM10 acts as a tumor suppressor in osteosarcoma. This could enable to define a new strategy for diagnosis and treatment of patients with osteosarcoma.

Bergapten exerts inhibitory effects on diabetes-related osteoporosis via the regulation of the PI3K/AKT, JNK/MAPK and NF-κB signaling pathways in osteoprotegerin knockout mice.

Diabetes, as a serious metobolic disorder, poses global threat to human health. It is estimated that over 50 million individuals are already affected by diabetes. Currently, diabetes-related osteoporosis has been a research hotspot due to its high incidence rate in older individuals. Osteoprotegerin, as an important protein for the prevention of osteoporosis, has been proven to be key to the suppression of osteoporosis. Hence, the loss of function of osteoprotegerin may promote the development of osteoporosis. Bergapten, as a natural anti-inflammatory and anti-tumor agent isolated from bergamot essential oil, other citrus essential oils, and grapefruit juice, has been proven to have the ability to attenuate a number of metabolic disorders. In view of these findings, in this study, we used a high-fat diet to construct a mouse model of diabetes-related osteoporosis and a mouse model of diabetes-related osteoporosis using osteoprotegerin knockout mice. Enzyme-linked immunosorbent assay (ELISA), qPCR, western blot analysis, immunohistochemical assay, H&E staining, Oil Red O staining, Masson's staining and other biochemical analyses were used to evaluate the related signaling pathways involved in the development of diabetes-related osteoporosis. We also examined the role of osteoprotegerin in the activation of these pathways and in the development of osteoporosis, as well as the protective effects of bergapten against diabetes-related osteoporosis and on the activation of related signaling pathways. Our results revealed that in diabetes-related osteoporosis, the phosphoinositide 3-kinase (PI3K)/AKT, c-Jun N-terminal kinase (JNK)/mitogen-activated protein kinase (MAPK) and nuclear factor-κB (NF-κB) signaling pathways were activated and the expression levels of related indicators were increased. At the same time, osteoprotegerin knockout further promoted the activation of these pathways. By contrast, bergapten exerted effects similar to those of osteoprotegerin. Bergapten exhibited the ability to significantly inhibit RANKL-RANK signaling transduction, and to suppress the activation of the PI3K/AKT, JNK/MAPK and NF-κB signaling pathways, thus protecting trabecular structure and decreasing osteoclastogenic differentiation.