Mechanism Research Of TGF-? Inhibitor RepSox Suppressing The Osteosarcoma Via JNK/Smad3 Signaling Pathway

Purpose:Osteosarcoma is the most common bone malignancy in the clinic.Thanks to the extensive use of neoadjuvant chemotherapy,the five-year survival rate of osteosarcoma patients has reached 70%.However,the long-term survival rate of patients with osteosarcoma who are relapse,metastasis and resistant to chemotherapy is still worrying.Therefore,it is urgent to study the pathogenesis of osteosarcoma and find new effective therapeutic drugs.Studies have shown that TGF-? plays an important role in tumor progression,and TGF-p inhibitors have been shown to have multiple effects on anti-tumor.RepSox is a highly potent TGF-? inhibitor that has been found to have effects on anti-tumor,anti-fibrotic,and anti-osteoporosis.In consideration of anti-tumor effect of RepSox,this study is aiming to prove the therapeutical effect of RepSox on osteosarcoma.Methods:In this study,we examined the effect of RepSox on the proliferation of human osteosarcoma cell lines HOS/143B by CCK-8 cell proliferation assay and colony assay.The effect of RepSox on cell cycle was studied by cell cycle flow.The effect of RepSox on apoptosis was investigated by apoptotic flow and TUNEL fluorescence staining.The effect of RepSox on migration was investigated by scratch test,Transwell experiment and QPCR.The effect of RepSox on the JNK pathway and the Smad3 pathway was detected by WB.Finally,the nude mouse model of allogeneic subcutaneous implantation was established and given intraperitoneal injection of different concentration of RepSox,and the anti-tumor effect of the drug in vivo was observed.Results:RepSox could inhibit the proliferation ability of osteosarcoma cells,leading to cell cycle arrest in S phase and promoting apoptosis in osteosarcoma cells.At the same time,RepSox can inhibit the metastasis and invasion of osteosarcoma cells and inhibit the mRNA expression of MMP2 and MMP9.In addition,we found that RepSox is able to inhibit the JNK signaling pathway and the Smad3 signaling pathway.Finally,we found that RepSox inhibits the growth rates of osteosarcoma as well as promotes apoptosis in the tumor model of allogeneic subcutaneous implantation in nude mice.It means that RepSox also possess anti-tumor ability in vivo.Conclusion:According to our results,TGF-? inhibitor RepSox inhibits proliferation,migration and induces apoptosis of human osteosarcoma cells by suppressing JNK/Smad3 signaling pathway.The data mentioned above indicates that RepSox is a new potential anti-osteosarcoma drug.