Cannabidiol (CBD) use in breast cancer chemotherapy

Breast cancer constitutes a major global health problem, as it represents the most frequently diagnosed carcinoma and the leading cause of cancer death in women worldwide. In the last decades, cannabinoids have appeared as promising therapeutic agents in breast cancer. Cannabidiol (CBD), which is the main non-psychoactive phytocannabinoid, is one of the most promising. CBD inhibits the growth of breast tumors and decreases the migration, invasion, and metastases of mammary cancer cells. It has shown to be active in hormone-positive, HER-2 overexpressing, and TNBC tumors. Interestingly, this cannabinoid potentiates the effect of conventional antineoplastics such as paclitaxel (PTX), doxorubicin (DOX), and vinorelbine, allowing the reduction of their doses and consequently their adverse effects. Moreover, CBD is also able to palliate some of the major adverse effects associated with these antineoplastics (e.g., peripheral neuropathy related to PTX and cardiotoxicity associated with DOX), making their combination an attractive strategy to improve cancer therapy. Nevertheless, the low solubility and poor oral bioavailability of this cannabinoid hamper its administration limiting its clinical efficacy, making drug delivery systems such as micro and nanoparticles potential strategies for its administration.