Curcumin loaded polymeric micelles inhibit breast tumor growth and spontaneous pulmonary metastasis

This work aims to develop curcumin (Cur) loaded biodegradable self-assembled polymeric micelles (Cur-M) to overcome poor water solubility of Cur and to meet the requirement of intravenous administration. Cur-M were prepared by solid dispersion method, which was simple and easy to scale up. Cur-M had a small particle size of 28.2 ± 1.8 nm and polydisperse index (PDI) of 0.136 ± 0.050, and drug loading and encapsulation efficiency of Cur-M were 14.84 ± 0.11% and 98.91 ± 0.70%, respectively. Besides, in vitro release profile showed a significant difference between rapid release of free Cur and much slower and sustained release of Cur-M. Cytotoxicity study showed that the encapsulated Cur remained its potent anti-tumor effect. Furthermore, Cur-M were more effective in inhibiting tumor growth and spontaneous pulmonary metastasis in subcutaneous 4T1 breast tumor model, and prolonged survival of tumor-bearing mice. In addition, immunofluorescent and immunohistochemical studies also showed that tumors of Cur-M-treated mice had more apoptosis cells, fewer microvessels, and fewer proliferation-positive cells. In conclusion, polymeric micelles encapsulating Cur were developed with enhanced anti-tumor and anti-metastasis activity on breast tumor, and Cur-M is excellent water-based formulation of Cur which may serve as a candidate for breast cancer therapy.