Abstract:

Objective To observe the effect of human mesenchymal stem cells （hMSCs） conditioned medium （CM） co-cultured with the human liposarcoma SW872 cells on the proliferation and migration of the tumor cells， and to discuss the effect of hMSCs CM on the liposarcoma cells and the possible mechanism. Methods The hMSCs were cultured in vitro and transfected with either lentiviral vector control shNS （control group） or lentiviral shRNA targeting Yes-associated protein （YAP） （shYAP-hMSCs group） by lentiviral methods. The expression levels of YAP mRNA and protein in the hMSCs in various groups were detected by real-time fluorescence quantitative PCR （RT-qPCR） and Western blotting methods. The CM was then harvested. The SW872 cells were cultured in vitro and divided into control group （normal culture）， hMSCs CM group， and shYAP-hMSCs CM group. The proliferation activities of the cells in various groups were detected by CCK-8 assay； the apoptotic rates of the cells in various groups were detected by flow cytometry； the scratch healing rates of the cells in various groups were detected by cell scratch assay； the expression levels of YAP， matrix metallopeptidase-9 （MMP-9）， and cyclin D1 proteins in the cells in various groups were detected by Western blotting method. Results Compared with control group， the expression levels of YAP mRNA and protein in the cells in shYAP-hMSCs group were decreased （P<0.01）， indicating the successful establishment of a stable transfected cell line. The CCK-8 assay results showed that compared with control group， the proliferation activity of the cells in hMSCs CM group was increased （P<0.05）， and the proliferation activity of the cells in shYAP-hMSCs CM group was decreased （P<0.01）. The flow cytometry results showed that compared with control group， there was no significant change in the apoptotic rate of the cells in hMSCs CM group （P>0.05）， while the apoptotic rate of the cells in shYAP-hMSCs CM group was increased （P<0.01）. The cell scratch assay results showed that compared with control group，the scratch healing rate of the cells in hMSCs CM group was increased （P<0.05）， and the scratch healing rate of the cells in shYAP-hMSCs CM group was decreased （P<0.01）. The Western blotting results showed that compared with control group， there were no significant differences in the expression levels of YAP， MMP-9， and cyclin D1 proteins in the cells in hMSCs CM group （P>0.05）， while the expression levels of YAP， MMP-9， and cyclin D1 proteins in the cells in shYAP-hMSCs group were decreased （P<0.05 or P<0.01）. Conclusion The hMSCs regulate the proliferation and migration of the human liposarcoma SW872 cells， and its mechanism may be related to the expression of YAP.

Key words: Human bone marrow mesenchymal stem cell, Conditioned medium, Liposarcoma, Cell proliferation, Cell migration, Yes-associated protein