In contrast, we found less staining of phospho-Src and -AKT, as well as lower percentages of Ki67-positive cells, in tumors derived from mice treated with either free or NP-associated saracatinib (Fig. 4g and Additional file 6: Figure S6), suggesting that Nano-sar has the great potential to induce tumor shrinkage and inactivate targeting proteins than free drug. This evidence concerns the gene MKI67 and neoplasm.