Impact of nanotechnology on the delivery of natural products for cancer prevention and therapy

Chemoprevention of human cancer by dietary products is a practical approach of cancer control, especially when chemoprevention is involved during the early stages of the carcinogenesis process. Research over the last few decades has clearly demonstrated the efficacy of dietary products for chemoprevention in cell culture and preclinical animal model systems. However, these in vitro and in vivo effects have not been able to be translated to bedside for clinical use. Among many reasons, inefficient systemic delivery and bioavailability of promising chemopreventive agents are considered to significantly contribute to such a disconnection. Since its advent in the field of cancer, nanotechnology has provided researchers with expertise to explore new avenues for diagnosis, prevention, and therapy of the disease. In a similar trait, we introduced a novel concept in which nanotechnology was utilized for enhancing the outcome of chemoprevention (Cancer Res. 2009; 69:1712–1716). This idea, which we termed as ‘nanochemoprevention’, was exploited by several laboratories and has now become an advancing field in chemoprevention research. This review summarizes some of these applications of nanotechnology in medicine, particularly focused on controlled and sustained release of bioactive compounds with emphasis on current and future utilization of nanochemoprevention for prevention and therapy of cancer. Nanotechnology‐based delivery of bioactive food components has several salient features that include improved drug delivery, potential to enhance tumor control, and minimized side effects. Such nanodelivery systems possess unique properties that allow them to modulate the pharmacokinetic and pharmacodynamic profiles of the payload. Loading of drugs in nanocarriers increases their in vivo stability, extend a compound's blood circulation time, and allow for controlled and sustained drug release. Importantly, nanocarriers can be modified to target a specific organ in a cancer cell‐ or tissue‐specific manner.