For this purpose, a series of MS with EpoB and Rap were obtained from pure PLA or from a mixture of PLA and PLA–PEG (Table 1), which were compared with PLA–PEG micelles to assess the influence of the DDS type, its morphology, and polymer composition on the drugs’ release process and cytotoxicity against breast cancer cells. Here, LRPAP1 is linked to breast cancer.