Nanotechnology for cancer treatment: Possibilities and limitations

Abstract

Drug delivery to solid tumors is one of the seminal challenges to developing more effective cancer therapies. A well-designed drug delivery system can potentially improve the efficacy of a treatment by enhancing drug accumulation in the tumor and combining synergistic effects into a single package. It may also reduce negative side effects by limiting drug access to sensitive noncancerous tissue. The most common drug delivery design is to package small molecule drugs with a nanoparticle. Nanotechnology provides a versatile platform onto which many functions can be added. Nanoparticles are widely considered to have superior biodistribution and efficacy when compared to free drug particles, but this expectation has not matched clinical results. One reason for the disappointing clinical outcomes of nano-sized drug carriers is the numerous barriers to drug delivery encountered by the nanoparticle on route from the administration site to tumor interior. These barriers are encountered along the entire delivery pathway and can severely limit the total effective amount of drug in the tumor.