Nano-based delivery systems for berberine: A modern anti-cancer herbal medicine

Berberine (BBR) is an isoquinoline alkaloid belonging to the structural class of protoberberines. BBR has been used in traditional medicine to treat diseases, such as type 2 diabetes and hypercholesterolemia. BBR inhibits cancer cell growth and induces apoptosis. However, BBR has significant drawbacks as a chemotherapeutic agent, including poor solubility, and induction of drug resistance, limiting its application in chemotherapy. Hence, combination therapy could not only deal with the problems related to single-agent chemotherapy but could also improve the therapeutic index of anticancer drugs. Co-administration of drugs may show pharmaceutical incompatibility due to conflicting physicochemical features. BBR can be used in nanoparticle-based single drug delivery, and in co-delivery systems designed to accommodate drugs and deliver them simultaneously into cancer cells. In this review, we will summarize the use of BBR, including BBR as a single chemotherapeutic agent and the combination of BBR with traditional anti-cancer drugs or herbal medicines in nanoparticle-based delivery systems.