Effect of mesenchymal stem cells on the apoptosis of breast cancer cells induced by cisplatin / 中华肿瘤杂志

ABSTRACT

Objective@#To investigate the effect of mesenchymal stem cells (MSCs) on apoptosis of breast cancer cell line MCF-7 induced by cisplatin (DDP), MSCs derived from breast cancer (BC-MSCs) or adjacent non-cancerous tissues (BN-MSCs) were isolated, cultured and identified.@*Methods@#BC-MSCs and BN-MSCs were isolated and cultured by tissue adherent method. The differentiation potential of BC-MSCs was detected by osteogenic and adipogenic induction, and cell surface markers of BC-MSCs and BN-MSCs were evaluated by flow cytometry. MCF-7 cells were co-treated with DDP and conditioned medium (CM) collected from BC-MSCs and BN-MSCs after being cultured for 48 hours, respectively. Inhibition rate of cell proliferation was evaluated by MTT. Cell apoptosis and viability were detected by MUSE cell analyzer. Cytokines in MSC-CM were detected by Luminex liquid chip. Interleukin 6 (IL-6) mRNA expressions in MCF-7 cells with different treatment were detected by RT-PCR.@*Results@#The morphology of BC-MSCs and BN-MSCs successfully isolated and cultured was uniform fibroblast-like clusters under the microscope. These cells expressed high levels of CD29 and CD44, but neither CD14 nor CD34 were detected. MSCs could also differentiate into osteoblasts and adipocytes after specific induction. After treatment with 2.5, 5, 10, 20, 40 and 80 μmol/L DDP, the inhibitory rates of proliferation of MCF-7 cells in DDP group were (17.33±2.00)%, (22.37±0.73)%, (30.77±1.23)%, (44.93±1.27)%, (62.03 ±1.97)% and (73.93±1.10)%, respectively. While the inhibitory rates of DDP+ BC-MSCs group were (8.27±0.63)%, (11.50±1.30)%, (20.57±0.93)%, (32.60 ±1.90)%, (52.27±0.73)% and (62.13±2.17)%, respectively. The inhibitory rates of DDP+ BN-MSCs group were (12.90±1.60)%, (16.53±2.87)%, (25.90±1.50)%, (39.40±2.40)%, (57.40±0.70)% and (69.03±1.07)%, respectively. The inhibitory rates of DDP+ BC-MSCs group were significantly lower than those of DDP group (P<0.05). The apoptotic rates of MCF-7 cells in DDP group, DDP+ BC-MSCs group and DDP+ BN-MSCs group were (47.77±1.98)%, (29.20±2.12)% and (37.92±2.21)%, respectively. The apoptotic rates of DDP group was significantly higher than that of DDP+ BC-MSCs group (P<0.05). The cell viabilities of MCF-7 in DDP group, DDP+ BC-MSCs group and DDP+ BN-MSCs group were 0.52±0.02, 0.72±0.02 and 0.64±0.02, respectively. The cell viability of DDP group was significantly lower than that of DDP+ BC-MSCs group (P<0.05). The result of Luminex liquid chip analysis showed that, the level of IL-6 in BC-MSCs group increased 2.50±0.68 fold when compared with BN-MSCs group (P<0.05). The relative expressions of IL-6 mRNA in DDP group and DDP+ BC-MSCs group were 1.02±0.10 and 7.58±0.55, respectively, with a statistically significant difference (P<0.01). The apoptotic rates of MCF-7 cells in DDP+ BC-MSCs group with or without IL-6 neutralizing antibody were (27.41±1.95)% and (42.45±2.87)%, respectively, with a statistically significant difference (P<0.05). The cell viabilities of MCF-7 cells in DDP+ BC-MSCs group with or without IL-6 neutralizing antibody were (72.40±2.60)% and (59.76±3.89)%, respectively, with a statistically significant difference (P<0.05).@*Conclusions@#BC-MSCs and BN-MSCs have been isolated and cultured successfully. Compared with BN-MSCs, BC-MSCs could attenuate the effect of DDP on MCF-7 cells, evidently decrease the apoptosis and increase the proliferation and vitality in an IL-6 dependent manner.