Impact of the enhanced permeability and retention (EPR) effect and cathepsins levels on the activity of polymer-drug conjugates

Rajora, A. K., Ravishankar, D., Osborn, H. M.I. ORCID: https://orcid.org/0000-0002-0683-0457 and Greco, F. (2014) Impact of the enhanced permeability and retention (EPR) effect and cathepsins levels on the activity of polymer-drug conjugates. Polymers, 6 (8). pp. 2186-2220. ISSN 2073-4360 doi: 10.3390/polym6082186

Abstract/Summary

Polymer-drug conjugates have demonstrated clinical potential in the context of anticancer therapy. However, such promising results have, to date, failed to translate into a marketed product. Polymer-drug conjugates rely on two factors for activity: (i) the presence of a defective vasculature, for passive accumulation of this technology into the tumour tissue (enhanced permeability and retention (EPR) effect) and (ii) the presence of a specific trigger at the tumour site, for selective drug release (e.g., the enzyme cathepsin B). Here, we retrospectively analyse literature data to investigate which tumour types have proved more responsive to polymer-drug conjugates and to determine correlations between the magnitude of the EPR effect and/or expression of cathepsin B. Lung, breast and ovarian cancers showed the highest response rate (30%, 47% and 41%, respectively for cathepsin-activated conjugates and 31%, 43%, 40%, across all conjugates). An analysis of literature data on cathepsin content in various tumour types showed that these tumour types had high cathepsin content (up to 3835 ng/mg for lung cancer), although marked heterogeneity was observed across different studies. In addition, these tumour types were also reported as having a high EPR effect. Our results suggest that a pre-screening of patient population could bring a more marked clinical benefit.

Item Type	Article
URI	https://reading-clone.eprints-hosting.org/id/eprint/37492
Item Type	Article
Refereed	Yes
Divisions	Life Sciences > School of Chemistry, Food and Pharmacy > School of Pharmacy > Medicinal Chemistry Research Group Life Sciences > School of Chemistry, Food and Pharmacy > School of Pharmacy > Pharmaceutics Research Group
Publisher	MDPI
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