Nanodrug Delivery Systems Modulate Tumor Vessels to Increase the Enhanced Permeability and Retention Effect

Abstract

The use of nanomedicine for antitumor therapy has been extensively investigated for a long time. Enhanced permeability and retention (EPR) effect-mediated drug delivery is currently regarded as an effective way to bring drugs to tumors, especially macromolecular drugs and drug-loaded pharmaceutical nanocarriers. However, a disordered vessel network, and occluded or embolized tumor blood vessels seriously limit the EPR effect. To augment the EPR effect and improve curative effects, in this review, we focused on the perspective of tumor blood vessels, and analyzed the relationship among abnormal angiogenesis, abnormal vascular structure, irregular blood flow, extensive permeability of tumor vessels, and the EPR effect. In this commentary, nanoparticles including liposomes, micelles, and polymers extravasate through the tumor vasculature, which are based on modulating tumor vessels, to increase the EPR effect, thereby increasing their therapeutic effect.

Design and Evaluation of 223Ra-Labeled and Anti-PSMA Targeted NaA Nanozeolites for Prostate Cancer Therapy—Part II. Toxicity, Pharmacokinetics and Biodistribution

“…The most likely explanation for the observed low tumor deposition of 223 RaA-silane-PEG-D2B is the relatively high hydrodynamic diameter of 223 RaA-silane-PEG-D2B (~250 nm) and low Enhanced Permeability and Retention effect (EPR), which is responsible for extravasation and retention of nanocarriers in tumors [55]. Though tumors growing in the subcutaneous microenvironment have a functional pore cut-off size ranging from approximately 10 nm to 1000 µm [55][56][57], the size of endothelial fenestrae and vascular permeability in tumors is highly heterogeneous and depends on tumor type, development and growth [58]. It was reported that slow-growing tumors, such as the prostate tumor, have a decreased EPR effect and are usually difficult to treat with nanomedicine [59].…”

Stimuli-Responsive Polymeric Nanoplatforms for Cancer Therapy

“…Passive targeting is directly associated with the nanoparticles' inherent properties, including size, shape, charge, flexibility, etc. Nanotechnology has accelerated the development of polymeric drugs for cancer therapy because polymeric nanomaterials can alter the physicochemical features such as size, shape and charge potential to enhance the EPR effect directly or indirectly (Maeda et al, 2009;Huang et al, 2021). The typical size of nanosystems ranges from 5 to 200 nm to avoid kidney filtration and extravasate the leaky vasculature in tumor (Dai et al, 2017).…”

Delivery of microRNA-21-sponge and pre-microRNA-122 by MS2 virus-like particles to therapeutically target hepatocellular carcinoma cells

“…13 MS2 VLPs are nuclease resistant and can protect RNA cargos from degenerating in circulation. 12 MS2 VLPs are as small as 27.5 nm, compared with most nanoparticles, which are approximately 100-200 nm, 14 so VLPs leave circulation more easily and contact tumor cells independent of the apparatus. 15 The amino acid residues located outside the capsid make it possible to conjugate the VLPs with functional peptides, such as cell-specific peptides, penetrating peptides and lysosome escape peptides.…”