FBXO28-mediated Ubiquitination Of NOTCH1 Promotes Malignant Progression Of Osteosarcoma

Objective:Osteosarcoma is one of the most common primary malignant bone tumors,typically occurring in children and young adults.Normally,the 5-year survival rate for osteosarcoma patients after treatment is around 65-70%.However,if the patient experiences tumor metastasis,their survival rate may be significantly lower,often less than 20%.As a result,there is an urgent need to investigate the pathogenesis of osteosarcoma and identify new therapeutic targets to improve patient prognosis.The purpose of this study is to explore whether FBXO28 regulates the malignant progression of osteosarcoma and how it promotes this progression through ubiquitination mechanisms.By conducting an in-depth analysis of the interaction between FBXO28 and NOTCH1 and its regulatory effect on NOTCH1,we aim to provide new therapeutic targets and drug strategies for the treatment of osteosarcoma and improve treatment efficacy in clinical practice.Method:1.The effects of overexpression or knockdown of FBXO28 on osteosarcoma cells were analyzed using protein blotting,real-time PCR,CCK-8,Transwell,cloning formation,and apoptosis cycle detection analysis.2.The interaction between FBXO28 and NOTCH1 was validated using protein blotting and immunoprecipitation.The interaction domains were investigated using constructed domain plasmids,and the effect of FBXO28 on the ubiquitination of NOTCH1 was explored using in vivo ubiquitination assays.3.The Real-time fluorescence quantitative PCR was used to explore the effect of FBXO28 on the downstream target genes of NOTCH1.Results:1.Overexpression of FBXO28 promotes the malignant progression of osteosarcoma.2.Knockdown of FBXO28 inhibits the malignant progression of osteosarcoma.3.FBXO28 interacts with NICD.4.FBXO28 regulates NICD through ubiquitination.5.Knockdown of NOTCH1 can block the regulatory effect of FBXO28 on osteosarcoma cells.Conclusion:FBXO28 is highly expressed in osteosarcoma tissue,and its upregulation promotes the malignant progression of osteosarcoma.Conversely,knocking down FBXO28 can inhibit the malignant progression of osteosarcoma.FBXO28 interacts with NICD and regulates its function through ubiquitination.In addition,knocking down NOTCH1 can block FBXO28’s regulatory effect on osteosarcoma cells.These results suggest that FBXO28 may be a potential therapeutic target for treating osteosarcoma,with important clinical implications.