Fig. 3

The effects of upregulation or knockdown of SPOP under treatment with sunitinib or IFN-α2b on RCC cell proliferation and apoptosis. (A and B) The cells were incubated with the indicated drug concentrations for 48 h and subjected to ELISA to analyse the OD450 and calculate the proliferation inhibitory rate of the cells. Sunitinib or IFN-α2b at several concentrations significantly increased the proliferation rate of RCC cells overexpressing SPOP compared to that of RCC cells with low expression of SPOP (*, P < 0.05, **, P < 0.01. ***, P < 0. 001. ****, P < 0.0001). (C and D) RCC cells were treated with different concentrations of sunitinib or IFN-α2b, collected and stained with Annexin V-APC and 7-AAD. The total apoptosis rate consisted of early apoptosis (Q3) and late apoptosis (Q2) and was quantified by flow cytometry. The total apoptosis rate of RCC cells overexpressing SPOP increased with increasing drug concentrations, and the SPOP protein may improve the susceptibility of RCC cells to drug treatments