Advances in nano drug delivery systems for enhanced efficacy of emodin in cancer therapy

Cancer remains one of the leading causes of death worldwide, highlighting the urgent need for novel antitumor drugs. Natural products have long been a crucial source of anticancer agents. Among these, emodin (EMO), a multifunctional anthraquinone compound, exhibits significant anticancer effects but is hindered in clinical applications by challenges such as low solubility, rapid metabolism, poor bioavailability, and off-target toxicity. Nano drug delivery systems offer effective strategies to overcome these limitations by enhancing the solubility, stability, bioavailability, and targeting ability of EMO. While substantial progress has been made in developing EMO-loaded nanoformulations, a comprehensive review on this topic is still lacking. This paper aims to fill this gap by providing an overview of recent advancements in nanocarriers for EMO delivery and their anticancer applications. These carriers include liposomes, nanoparticles, polymeric micelles, nanogels, and others, with nanoparticle-based formulations being the most extensively explored. Nanoformulations encapsulating EMO have demonstrated promising therapeutic results against various cancers, particularly breast cancer, followed by liver and lung cancers. We systematically summarize the preparation methods, materials, and physicochemical properties of EMO-loaded nanopreparations, underscoring key findings on how nanotechnology improves the anticancer efficacy of EMO. This review provides valuable insights for researchers engaged in developing nano delivery systems for anticancer drugs.