Transmission electron microscopy (TEM) revealed the formation of spherical BTA@CD-Man7 nanoparticles with an average diameter of 117 ± 16 nm, whereas confocal laser scanning microscopy (CLMS) showed that the nanoparticles were efficiently internalized in MDA-MB-231 breast cancer cells overexpressing the mannose receptor (MR), but not in healthy MCF-10A cells. This evidence concerns the gene NR3C2 and breast carcinoma.