Fig. 6

SKP2 inhibitor SMIP004 increases the effect of tumor radiotherapy. a SMIP004 downregulated SKP2 expression levels and upregulated PDCD4 expression levels. 293 T cells were transfected with Flag-SKP2 and control plasmid for 48 h, then untreated or treated with SMIP004(40 μM) for 24 h and harvested for IB. b, c MCF-7 or MDA-MB-231 were treated or untreated with SMIP004 (40 μM) for 24 h, then untreated or treated with radiation (6GY), followed by MTT assay (n = 3). d, e MCF-7 or MDA-MB-231 were treated or untreated with SMIP004 (40 μM) for 24 h, then untreated or treated with radiation (6GY), followed by clonogenic survival assay (n = 3). f, j MCF-7 or MDA-MB-231 cells were subcutaneously injected into nude mice (n = 5 for each group), then untreated or treated with radiation at 0.1GY/min for 10 min twice a week from 4 to 6 week or radiation at 0.1GY/min for 10 min and SMIP004 (50 mg/kg) twice a week from 4 to 6 week. A photo of five tumors aligned together were presented. g, k  Tumor weight was measured. h, l Tumor size was monitored and calculated by caliper for up to 6 weeks (see Methods). i, m Breast tumors were harvested from nude mice at 6 week for Caspase-3 staining by IHC and quantitated (Scale bars, 50 um, Scale bars inside the box, 20 um). b-e, g-i, k-m Data represent the mean ± SEM of three independent experiments. Student’s t-test used: *P < 0.05; **P < 0.01