Figure 4

E5 enhanced the sensitivity of 4T1 cells to different chemotherapeutic drugs in co-culture models. (a) The cytotoxicity of paclitaxel (10 μM), elemene (10 mg l⁻¹), and cisplatin (8 μM) on 4T1 cells pre-treated with E5 (10 μM) and co-cultured with MS-5 cells. The viability of 4T1 cells pre-treated with 10 μM E5 with paclitaxel (4, 20 and 100 nM), elemene (10, 20 and 40 mg l⁻¹) or cisplatin (2, 4 and 8 μM) for 24 h in the presence of MS-5 conditional medium (b) or medium supplemented with CXCL12 (c). The viability percentage of 4T1 cells in the absence of treatment was set as 100%. The data are presented as the means±s.d. (n=4). * represents P<0.05 and ** represents P<0.01, respectively.