Figure 1.

Sunitinib treatment significantly inhibited tumor growth and tumor angiogenesis of the basal-like triple-negative breast cancer. Oral sunitinib significantly suppressed the basal-like TNBC growth curve of tumor volume in MDA-MB-468/xenografts (A). When the tumor volume reached around 100 mm³, four female athymic nude-Foxn1 mice received sunitinib given by gavage at 80 mg/kg/2 days for 4 weeks and the other 4 mice received the vehicle only as the control group. At the conclusion of the experiment, the tumor volume was significantly reduced by 90.4% (p < 0.01; n = 4) in the sunitinib-treated group in contrast to the control group, which was consistent with the reduction in tumor weight in the sunitinib-treated group compared to the control group (31 ± 0.6 vs. 294 ± 28 mg; P <0.01). The digital images of CD31 staining of the basal-like TNBC tumors showed that the sunitinib-treated tumor had fewer microvessels than the control tumor (B). Morphometric analysis (B) indicated that sunitinib- treatment caused a significant decrease in average microvessel density (the number of microvessels per mm² area) of the basal-like TNBC tumors when compared to the control tumors (72 ± 8 vs. 114 ± 10 microvessels number per mm²; n = 4; p < 0.01).