Fig. 1
From: Active targeting schemes for nano-drug delivery systems in osteosarcoma therapeutics
A schematic illustration of active targeting and passive targeting of nano-delivery system in anti-tumor therapy. Passive targeting is achieved via enhanced permeability and retention (EPR) effects. Nanocarriers circulate in the bloodstream, extravasate, and accumulate into tumor tissue through the leaky tumor vasculature. Targeting ligand-modified nanocarriers are able to bind to highly expressed receptors on the tumor cell, exerting local drug delivery or internalization through receptor-mediated endocytosis