Background and purpose: Osteosarcoma is the most common primary malignancy in bone tumors. So far

the molecular mechanism of the development of osteosarcoma is not clear

and there is no effective therapeutic drug in clinic. This study explored the relationship between Notch1 protein and osteosarcoma and whether their influence involved in the occurrence and development of Notch-Wnt signal pathways. Methods: The expression levels of Notch1 mRNA and protein in tissue specimens were detected by immunohistochemistry

real-time fluorescent quantitative polymerase chain reaction (RTFQ-PCR) and Western blot. Transfection of siRNA interference Notch1 gene was carried out in MG-63 and U-2 OS osteosarcoma cell lines respectively to achieve reduction of Notch1 osteosarcoma cells. Osteosarcoma cell proliferation and apoptosis were determined by MTT test and flow cytometry. RTFQ-PCR and Western blot were used to detect the protein content changes of Notch and Wnt signaling pathway. Results: Notch1 in the tissue of bone sarcoma obtained by biopsy was positive. Notch1 siRNA significantly inhibited MG-63 and U-2 OS cells proliferation

and promoted apoptosis. It showed that the protein expression decreased significantly in Notch and Wnt signaling pathway after transfection of osteosarcoma cells with Notch1-siRNA. Conclusion: Notch1 plays a role in promoting proliferation by influencing the Notch-Wnt signaling pathway in the occurrence and development of osteosarcoma.