Abstract 487: Peptide amphiphiles hitchhike on endogenous biomolecules for enhanced drug delivery

Abstract

Abstract Peptide amphiphiles (PAs) have been applied as building blocks for self-assembled nanostructures with various morphologies. These self-assembled nanostructures are promising drug delivery platforms as they are naturally biodegradable and biocompatible with low immunogenicity. One primary focus in drug delivery using the PA nanostructures has been to develop strongly assembled structures to avoid disassembly in the blood and allow them to carry payloads to their intended targets. In this work, rather than developing stable self-assembled PA structures, we focused on weakly assembled PA nanostructures to investigate their interactions with blood components and to understand how these interactions affect their biodistribution. We found that weakly assembled PA nanostructures (SA-E) quickly disassembled in plasma and reassembled with lipoproteins (LPs), which significantly prolonged the blood circulation of SA-E in mice. We showed that SA-E crossed the endothelial barriers through transcytosis only when they were assembled with LPs. Cellular uptake studies showed that SA-E accumulated in cancer cells through lipid-raft-mediated uptake. Interestingly, their cellular internalization was independent of LP receptors, suggesting that SA-E assembles with different endogenous biomolecules in vivo. By exploiting these endogenous interactions, SA-E demonstrated high tumor accumulation in a myriad of small animal tumor models of breast, colon, pancreatic, brain, skin, prostate, or lung cancers. SA-E demonstrated large tumor-to-background signal ratios in live animals (>5), extended retention (>2 weeks), and excellent tissue distribution (tumor to liver signal >3) in these tumor models. Encouraged by the excellent tumor accumulation of SA-E, we prepared SA-E drug conjugate using a highly potent and toxic chemotherapeutic agent, Monomethyl auristatin E (MMAE). SA-E-MMAE conjugate demonstrated strong antitumor efficacy in aggressive breast and glioma models in mice with reduced side effects. With its simple and modular design and universal tumor accumulation mechanism, SA-E represents a promising platform for broad applications in cancer therapy. Citation Format: Jared M. Fischer, Morgan Stewart, Mingchong Dai, Samuel Drennan, Sinan Sabuncu, Benjamin Kingston, Isabel Dengos, Li Xiang, Karla Bonic, Xin Yi, Srivathsan Ranganathan, Bruce Branchaud, Adem Yildirim. Peptide amphiphiles hitchhike on endogenous biomolecules for enhanced drug delivery [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 487.