2023, Vol. 27 ›› Issue (10): 1514-1520

Effects of multiple myeloma cell conditioned medium on proliferation and differentiation of human umbilical cord mesenchymal stem cells

Yang Xu1, Wang Feiqing2, Zhao Jianing1, Zhang Chike3, Liang Huiling1, Qi Shasha3, Wu Dan1, Liu Yanqing2, Tang Dongxin2, Liu Yang1, 2, 4, Li Yanju3   

Abstract: BACKGROUND: In recent years, the interaction between stem cells and tumor in tumor microenvironment has become a hot topic. While few studies have reported the experiments of human umbilical cord mesenchymal stem cells in conditioned culture medium of human multiple myeloma cells.   
OBJECTIVE: To investigate the effects of conditioned medium of human multiple myeloma cells on proliferation, migration and differentiation of human umbilical cord mesenchymal stem cells.
METHODS: Human umbilical cord mesenchymal stem cells were extracted by tissue block adherent method. At the same time, the supernatant of human multiple myeloma RPMI8226 and U266 cells was cultured and extracted to prepare conditioned culture medium. The cells were grouped according to different media: the control group was only cultured with L-DMEM complete culture medium. In experimental group, human umbilical cord mesenchymal stem cells were cultured with 20% RPMI8226 cell conditioned medium or 20% U266 cell conditioned medium and 80% L-DMEM complete medium. After 24 hours of culture, the proliferation of cells was analyzed by CCK8 assay, EDU, and crystal violet staining. The migration of cells was evaluated by the scrape method. Osteogenic and adipogenic induction experiments were used to detect cell differentiation. Real-time PCR was used to detect the mRNA expressions of cyclin genes p16 and p21 in cells.   
RESULTS AND CONCLUSION: The proliferation of cells in the experimental group was more than that in the control group (P < 0.05); the migration rate was higher than that in the control group (P < 0.05); the staining area of mineralized nodules was smaller than that of the control group (P < 0.05); and the positive staining area of lipid droplets was larger than that of the control group (P < 0.05); the mRNA expression of cell cycle genes p16 and p21 in the experimental group was lower than that in the control group (P < 0.05). These findings exhibit that conditioned culture medium of human multiple myeloma cells can promote the proliferation, migration, and adipogenic differentiation of human umbilical cord mesenchymal stem cells, and inhibit osteogenic differentiation. This may be associated with the inhibition of p16 and p21 gene expression.
Key words: multiple myeloma, conditioned medium, human umbilical cord mesenchymal stem cell, proliferation, differentiation