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Nano Research 2022, 15(1): 482-491 https://doi.org/10.1007/s12274-021-3507-8
Research Article | Open Access | Issue | Published: 19 May 2021

Vascular-confined multi-passage discoidal nanoconstructs for the low-dose docetaxel inhibition of triple-negative breast cancer growth

Show Author's Information Alessia Felici1,2,  Daniele Di Mascolo1,  Miguel Ferreira1,  Simone Lauciello3,  Luca Bono4,  Andrea Armirotti4,  Arunkumar Pitchaimani1,  Anna Lisa Palange1,§,  Paolo Decuzzi1,§( )
Laboratory of Nanotechnology for Precision Medicine Fondazione Istituto Italiano di Tecnologia Genoa 16163 Italy
Department of Informatics Bioengineering Robotics and System Engineering University of Genoa Genoa 16126 Italy
Nanochemistry Laboratory, Fondazione Istituto Italiano di Tecnologia Genoa 16163 Italy
Analytical Chemistry Laboratory Fondazione Istituto Italiano di Tecnologia Genoa 16163 Italy

§ Anna Lisa Palange and Paolo Decuzzi contributed equally to this work.

Keywords:
biomimicry, cancer therapy, hydrogel particles, template strategy, vascular targeting
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Nano biology
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Felici A, Mascolo DD, Ferreira M, et al. Vascular-confined multi-passage discoidal nanoconstructs for the low-dose docetaxel inhibition of triple-negative breast cancer growth. Nano Research, 2022, 15(1): 482-491. https://doi.org/10.1007/s12274-021-3507-8
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Abstract Full text Electronic supplementary material About this article

Taxane efficacy in triple negative breast cancer (TNBC) is limited by insufficient tumor accumulation and severe off-target effects. Nanomedicines offer a unique opportunity to enhance the anti-cancer potency of this drug. Here, 1, 000 nm × 400 nm discoidal polymeric nanoconstructs (DPN) encapsulating docetaxel (DTXL) and the near infrared compound lipid-Cy5 were engineered. DPN were obtained by filling multiple times cylindrical wells in a poly(vinyl alcohol) template with a polymer mixture comprising poly(lactic-co-glycolic acid) (PLGA) and poly(ethylene glycol) diacrylate (PEG-DA) chains together with therapeutic and imaging agents. The resulting "multi-passage" DPN exhibited higher DTXL loading, lipid-Cy5 stability, and stiffness as compared to the conventional "single-passage" approach. Confocal microscopy confirmed that DTXL-DPN were not taken up by MDA-MB-231 cells but would rather sit next to the cell membrane and slowly release DTXL thereof. Empty DPN had no toxicity on TNBC cells, whereas DTXL-DPN presented a cytotoxic potential comparable to free DTXL (IC50 = 2.6 nM ± 1.0 nM vs. 7.0 nM ± 1.09 nM at 72 h). In orthotopic murine models, DPN accumulated in TNBC more efficiently than free-DTXL. With only 2 mg/kg DTXL, intravenously administered every 2 days for a total of 13 treatments, DTXL-DPN induced tumor regression and were associated to an overall 80% survival rate as opposed to a 30% survival rate for free-DTXL, at 120 days. All untreated mice succumbed before 90 days. Collectively, this data demonstrates that vascular confined multi-passage DPN, biomimicking the behavior of circulating platelets, can efficiently deliver chemotherapeutic molecules to malignant tissues and effectively treat orthotopic TNBC at minimal taxane doses.


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Abstract
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Electronic supplementary material
About this article

Vascular-confined multi-passage discoidal nanoconstructs for the low-dose docetaxel inhibition of triple-negative breast cancer growth

Show Author's information Alessia Felici1,2, Daniele Di Mascolo1, Miguel Ferreira1, Simone Lauciello3, Luca Bono4, Andrea Armirotti4, Arunkumar Pitchaimani1, Anna Lisa Palange1,§, Paolo Decuzzi1,§( )
Laboratory of Nanotechnology for Precision Medicine Fondazione Istituto Italiano di Tecnologia Genoa 16163 Italy
Department of Informatics Bioengineering Robotics and System Engineering University of Genoa Genoa 16126 Italy
Nanochemistry Laboratory, Fondazione Istituto Italiano di Tecnologia Genoa 16163 Italy
Analytical Chemistry Laboratory Fondazione Istituto Italiano di Tecnologia Genoa 16163 Italy

§ Anna Lisa Palange and Paolo Decuzzi contributed equally to this work.

Abstract

Taxane efficacy in triple negative breast cancer (TNBC) is limited by insufficient tumor accumulation and severe off-target effects. Nanomedicines offer a unique opportunity to enhance the anti-cancer potency of this drug. Here, 1, 000 nm × 400 nm discoidal polymeric nanoconstructs (DPN) encapsulating docetaxel (DTXL) and the near infrared compound lipid-Cy5 were engineered. DPN were obtained by filling multiple times cylindrical wells in a poly(vinyl alcohol) template with a polymer mixture comprising poly(lactic-co-glycolic acid) (PLGA) and poly(ethylene glycol) diacrylate (PEG-DA) chains together with therapeutic and imaging agents. The resulting "multi-passage" DPN exhibited higher DTXL loading, lipid-Cy5 stability, and stiffness as compared to the conventional "single-passage" approach. Confocal microscopy confirmed that DTXL-DPN were not taken up by MDA-MB-231 cells but would rather sit next to the cell membrane and slowly release DTXL thereof. Empty DPN had no toxicity on TNBC cells, whereas DTXL-DPN presented a cytotoxic potential comparable to free DTXL (IC50 = 2.6 nM ± 1.0 nM vs. 7.0 nM ± 1.09 nM at 72 h). In orthotopic murine models, DPN accumulated in TNBC more efficiently than free-DTXL. With only 2 mg/kg DTXL, intravenously administered every 2 days for a total of 13 treatments, DTXL-DPN induced tumor regression and were associated to an overall 80% survival rate as opposed to a 30% survival rate for free-DTXL, at 120 days. All untreated mice succumbed before 90 days. Collectively, this data demonstrates that vascular confined multi-passage DPN, biomimicking the behavior of circulating platelets, can efficiently deliver chemotherapeutic molecules to malignant tissues and effectively treat orthotopic TNBC at minimal taxane doses.

Keywords: biomimicry, cancer therapy, hydrogel particles, template strategy, vascular targeting

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Publication history

Received: 25 September 2020
Revised: 01 April 2021
Accepted: 09 April 2021
Published: 19 May 2021
Issue date: January 2022

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© The Author(s) 2021

Acknowledgements

Acknowledgements

The authors wish to thank the reviewers for their valuable comments and suggestions to improve the quality of the paper. This project was partially supported by the European Research Council, under the European Union's Seventh Framework Programme (FP7/2007-2013)/ERC grant agreement No. 616695, by the Italian Association for Cancer Research (AIRC) under the individual investigator grant No. 17664, and by the European Union's Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No. 754490. The authors acknowledge the precious support provided by the Nikon Center, the Material Characterization Facility, the electron microscopy and nanofabrication facilities at the Italian Institute of Technology, and the work of Luca Caseracciu for the mechanical characterization of DPN.

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