Journey of Rosmarinic Acid as Biomedicine to Nano-Biomedicine for Treating Cancer: Current Strategies and Future Perspectives

Rosmarinic acid (RA) is a polyphenolic metabolite found in various culinary, dietary sources, and medicinal plants like Coleus scutellarioides (Linn) Benth., Lavandula angustifolia Linn., Mellisa officinalis Linn., Origanum vulgare Linn., Rosmarinus officinalis Linn., Zataria multiflora Boiss. and Zhumeria majdae Rech. F. Apart from its dietary and therapeutic values, RA is an important anticancer phytochemical owing to its multi-targeting anticancer mechanism. These properties provide a scope for RA's therapeutic uses beyond its traditional use as a dietary source. However, its oral bioavailability is limited due to its poor solubility and permeability. This impedes its efficacy in treating cancer. Indeed, in recent years, tremendous efforts have been put towards the development of nanoformulations of RA for treating cancer. However, this research is in its initial stage as bringing a nanoparticle into the market itself is associated with many issues such as stability, toxicity, and scale-up issues. Considering these pitfalls during formulation development and overcoming them would surely provide a new face to RA as a nanomedicine to treat cancer. A literature search was conducted to systematically review the various biological sources, extraction techniques, and anticancer mechanisms through which RA showed multiple therapeutic effects. Various nanocarriers of RA pertaining to its anticancer activity are also discussed in this review.