Affiliation: Department of Pharmacy, Annamalai University, Annamalai Nagar, Chidambaram, Tamil Nadu 608 002 India.
Cancer is one of the major causes of the death worldwide and its prevalence is expected to reach about 27 million by 2050 due to aging, adoption of cancer causing behaviours and limitations of cancer treatment. The major therapeutic approach for the treatment of cancer is chemotherapy but most chemotherapeutic agents experience some limitations including poor aqueous solubility, systemic toxicities and drug resistance. The better alternative seems to be functional foods, which are devoid of systemic toxicities at the therapeutic doses. Curcumin is one such functional food isolated from dried rhizome of turmeric and reported to inhibit proliferation, invasion, angiogenesis and metastasis of various cancer cells. However, the clinical usefulness of curcumin in the treatment of cancer is limited due to limited solubility in water, hydrolytic degradation in alkaline pH, metabolism via glucuronidation and sulfation and reduced oral bioavailability. Various approaches have been reported to overcome the limitation of conventional curcumin. Of all, nanotechnology is the most recent and showing encouraging results. This review highlighted the nanoparticulate drug delivery systems that have been developed to overcome the limitations of curcumin in the treatment of cancer. However, about 60-70% of an oral dose of curcumin gets eliminated as its metabolites and there were no reports of nanoparticulate drug delivery system that overcome the metabolism of curcumin. Bio-enhancer such as piperine, quercetin and silibinin prevent/minimize the metabolism of curcumin and utilizing these bio-enhancers along with curcumin as a dual drug loaded nanoparticles are hypothesized to overcome all the limitations of curcumin.