The DOX and MUC1 loaded nanoparticles were characterized physicochemically to determine their size, shape, surface charge, entrapment efficiencies, release behavior, etc. The cytotoxicity parameters of the DOX and MUC1 loaded nanoparticles (DM-PEG-PCL NPs) were evaluated and assessed against the breast cancer cell lines MCF-7 and MDA-MB-231. This evidence concerns the gene MUC1 and breast cancer.