Figure 2.

The mechanisms of nanoparticle entry into solid tumors. The escape of a nanoparticle from circulation into a solid tumor plays a pivotal role on a nanoparticle’s overall therapeutic efficacy, but this process is poorly understood. (A) The enhanced permeability and retention (EPR) effect, in which the nanoparticle enters the tumor through leaky tumor vasculature, and (B) transcytosis of the nanoparticle through intra-endothelial channels or vesicles in the absence of leakage between endothelial cells, as proposed by Sindhwani et al. [35]. Created with Biorender.com (accessed on 27 March 2022).