Cancer nanomedicine: emergence, expansion, and expectations

The introduction of cancer nanomedicine has substantially enhanced the effectiveness of cancer treatments. Nano-formulations are becoming more prevalent among other treatment methods due to their improved therapeutic efficacy and low systemic toxicity. The discovery of the enhanced permeability and retention (EPR) effect has led to the development of numerous nanodrugs that passively target tumours. Then researchers identified certain cancer cells overexpress certain receptors, targeting these over-expressing receptors using targeting moiety on the surface of the nanoparticles becomes promising and surface functionalization of nanoparticles has become an important area of cancer nanomedicine. This leads to the physiochemical modification of nanoparticles for strengthening the EPR effect and active targeting. This review comprehensively outlines the origins of cancer nanomedicine, the role of the EPR effect, the tools of nanotechnology and their specifications, and the nature of passive and active targeting, which gives important direction for the progress of cancer therapy using nanomedicine. The review briefly enlists the available nano formulations for different cancers and attempts were made to account for the barriers to clinical translation. The review also briefly describes the transition of research from nanomedicine to nano-immunotherapy.