Despite all the advances achieved in the field of tumor-biology research, in most cases conventional therapies including chemotherapy are still the leading choices. The main disadvantage of these treatments, in addition to the low solubility of many antitumor drugs, is their lack of specificity, which leads to the occurrence of severe side effects due to nonspecific drug uptake by healthy cells. Progress in nanotechnology and its application in medicine have provided new opportunities and different smart systems. Such systems can improve the intracellular delivery of the drugs due to their multifunctionality and targeting potential. The purpose of this manuscript is to review and analyze the recent progress made in cancer nanotherapy. First, we provide a global overview of cancer and different smart nanoparticles currently used in oncology. Then, we analyze in detail the development of drug-delivery strategies in cancer therapy, focusing mainly on the intravenously administered smart nanoparticles with protein corona to avoid immune-system clearance. Finally, we discuss the challenges, clinical trials, marketed nanomedicines and future directions of the nanotherapy applied to cancer treatment.
