Unique flower-like Cur-metal complexes loaded liposomes for primary and metastatic breast cancer therapy

Mounting researches continue to support a favorable role for the drug metal complex against cancer progress and metastasis. However, pharmaceutical barriers were encountered when drug metal complexes needed further pre-clinical and clinical evaluations due to their poor aqueous solubility. In this research, liposomes loaded metal ion as nano-scaled reaction vehicles were used to carry out a synthesis reaction between metal ion and curcumin (Cur) to prepare Cur-metal drug liposomal formulations. The unique flower-like conformation of Cur-M liposomes was observed for the first time and dominated in the Cur-M liposomal formulations system by the cryo-transmission electron microscopy. Different metal ions behaved significant differences in formulations' appearance, release profile, cytotoxic effect against various cell lines, pharmacokinetic profiles, biodistribution and antitumor efficiency. Cur-M liposomes presented enhanced cellular uptake and ROS generation effects, thus augmenting the cytotoxicity of Cur. Superior performances of Cur-copper complexes liposomes were observed in improving Cur stability, promoting apoptosis, inhibiting the proliferation and angiogenesis, therefore enhancing therapeutic effect for primary and metastatic breast cancer. Overall, the current work highlights the potentially significant development value of Cur-M liposomes as an injectable agent for cancer treatment, even superior to the commercial agent Doxil.