(B) Representative MRI images; Scale bar = 5mm and (C) quantification (mean ± S.E.M.) of relative tumor blood volume (rTBV) over time after NeuT+ mammary tumors were size-matched at 20-70mm3 (0 weeks). Treatments and genotypes are indicated. NeuT;Apln+/+ Control (n=4), NeuT;Apln-/- Control (n=4), NeuT;Apln+/+ Sunitinib (n=5), NeuT;Apln-/- Sunitinib (n=5); **P<0.01, and ***P<0.001 compared to untreated NeuT;Apln+/+ mice and #P<0.05 compared to untreated control NeuT;Apln-/- mice; two-way ANOVA. Of note, in NeuT;Apln+/+ mice, only 2 tumors could be analyzed after 6 weeks as some mice had to be sacrificed due to the large tumor sizes following ethical guidelines. Thus, we did not perform any statistical analysis on the 6 weeks timepoints. 