Adding Nanotechnology to the Metastasis Treatment Arsenal

Metastasis is a major cause of cancer-related mortality, accounting for 90% of cancer deaths. The explosive growth of cancer biology research has revealed new mechanistic network information and pathways that promote metastasis. Consequently, a large number of antitumor agents have been developed and tested for their antimetastatic efficacy. Despite their exciting cytotoxic effects on tumor cells in vitro and antitumor activities in preclinical studies in vivo, only a few have shown potent antimetastatic activities in clinical trials. In this review, we provide a brief overview of current antimetastatic strategies that show clinical efficacy and review nanotechnology-based approaches that are currently being incorporated into these therapies to mitigate challenges associated with treating cancer metastasis. Most existing antimetastatic drugs have proved to be insufficient for effective metastasis control.Chemotherapy, widely used for the treatment of primary tumors, can unexpectedly enhance prometastatic signaling in many cases.To overcome tumor resistance to one agent, clinical trials are often conducted with combination therapy comprising two or more drugs.Promising new approaches to metastasis, such as nanoparticle-based therapies, have the potential to complement and improve existing therapeutic options.