Elsevier

Journal of Controlled Release

Volume 319, 10 March 2020, Pages 407-415
Journal of Controlled Release

Transferrin-binding peptide functionalized polymersomes mediate targeted doxorubicin delivery to colorectal cancer in vivo

https://doi.org/10.1016/j.jconrel.2020.01.012Get rights and content

Highlights

  • Transferrin binding peptide decorated polymersomes (TBP-Ps) are easily obtained

  • TBP-Ps can selectively and stably bind transferrin (Tf@TBP-Ps)

  • Tf@TBP-Ps mediates targeted doxorubicin delivery to HCT-116 cancer cells

  • Dox-loaded Tf@TBP-Ps effectively inhibits HCT-116 colorectal tumor in vivo

Abstract

Transferrin receptor (TfR) is a promising target validated in the clinical trials for managing various malignancies. Transferrin (Tf) and single chain antibody fragment can target TfR and are typically conjugated to nanomedicines via post-modification, which poses significant production challenges. Here, we report that the polymersomes functionalized with a Tf-binding peptide CGGGHKYLRW (TBP-Ps) can selectively and stably bind Tf and subsequently mediate targeted doxorubicin (Dox) delivery to TfR over-expressing HCT-116 colorectal cancer cells in vitro and in vivo. The Tf surface density of the polymersomes could be controlled by the surface content of TBP. Interestingly, modifying Dox-loaded TBP-Ps with Tf led to greatly increased cellular uptake and inhibitory effect of HCT-116 cells. Tf-bound TBP-Ps demonstrated rapid accumulation in the tumor xenografts in nude mice following i.v. injection. More importantly, Dox-loaded Ps with Tf binding significantly enhanced the antitumor efficacy in mice bearing HCT-116 tumors compared to polymersomes without Tf binding. Surface functionalization of the nanoparticles with Tf-binding peptide provides an appealing strategy in formulating Tf-targeted nanomedicines.

Graphical abstract

Transferrin (Tf)-binding peptide CGGGHKYLRW functionalized polymersomes selectively and stably bind Tf and subsequently mediate targeted delivery of doxorubicin to TfR over-expressing HCT-116 colorectal cancer cells in vivo.

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Introduction

Targeted nanomedicines are considered as a future treatment modality for cancers [[1], [2], [3], [4]]. To accomplish targeted delivery, researchers have decorated nanomedicines with different ligands ranging from peptides [5,6], antibodies [7] and antibody fragments [8], glycoproteins [[9], [10], [11]], to folic acid [12,13]. In spite of intensive investigations, few actively targeted nanomedicines have come to the stage of clinical translation [[14], [15], [16]]. Notably, several targeted nano-formulations homing to transferrin receptor (TfR) have been approved for clinical trials [[17], [18], [19]]. TfR over-expresses on highly proliferative cancer cells [10,12,20]. Transferrin (Tf) and single-chain antibody fragment (ScFv) against TfR have been selected as ligands for TfR targeting [[21], [22], [23], [24], [25]]. For example, Davis et al. described that Tf-conjugated, cyclodextrin polymer-based nanoparticles exhibited an enhanced transfection of K562 leukemia cells as compared to the non-targeted control [26], and evidence of RNAi in a phase I clinical trial targeted delivery of siRNA to patients with solid tumor [27]. Chang et al. reported that liposomes modified with ScFv could mediate targeted delivery of wild-type p53 gene to metastatic pancreatic tumor. The results from phase I clinical trial revealed the accumulation of p53 gene in advanced solid tumor in patients, low adverse effects, and stablized disease [28]. However, the conjugation of large ligands like Tf and ScFv to nanomedicines via post-modification may pose significant production challenges. The post-modification with large ligands may encounter issues like poor control over conjugation site and efficacy, and difficulty in purification and in scaling up production.

In contrast to large glycoproteins and antibody fragments, peptides with a short sequence and easy handling enable functionalization of nanomedicines via pre-modification [29]. Various peptides have been screened as antibody alternatives for targeted tumor therapy in the past years [[30], [31], [32], [33], [34], [35]]. Nevertheless, to date, only BIND-014, a docetaxel nanoformulation decorated with prostate-specific membrane antigen-targeting peptide, has reached clinical assessments [36]. The slow development of peptide-targeted nanomedicines is likely due to the fact that peptides are not as specific and effective as antibodies for in vivo targeting. Interestingly, Signore et al. reported that CGGGHKYLRW as a Tf-binding peptide (TBP) showed a high specificity and affinity to Tf [37]. TBP following plasma incubation could promote TfR-mediated cellular uptake of gold nanoparticles.

Here, we report for the first time that Tf-binding peptide-functionalized polymersomes (TBP-Ps) loaded with doxorubicin hydrochloride (TBP-Ps-Dox) following Tf binding could mediate targeted Dox delivery to TfR over-expressing HCT-116 colorectal cancer cells in vitro and in vivo (Scheme 1). Several reports demonstrated that colorectal cancers over-express TfR [38,39]. We previously reported that the disulfide-crosslinked polymersome is a promising substitute to liposome for Dox delivery [[40], [41], [42], [43]]. Interestingly, TBP-Ps-Dox following Tf binding (Tf@TBP-Ps-Dox) revealed greatly enhanced cellular uptake and antitumor effect in HCT-116 cells over Ps-Dox. The pharmacokinetics and anti-tumor therapy experiments revealed that Tf@TBP-Ps-Dox exhibited a long circulation time and a considerably improved inhibition of HCT-116 tumor as compared to Ps-Dox. Surface functionalization of the nanoparticles with Tf-binding peptide thus provides an appealing strategy to fabricate nanomedicines targeting to TfR over-expressing malignancies.

Section snippets

Synthesis of TBP-PEG-P(TMC-DTC)

Poly(ethylene glycol)-b-poly(trimethylene carbonate-co-dithiolane trimethylene carbonate) (mPEG-P(TMC-DTC)) and maleimide functionalized copolymer Mal-PEG-P(TMC-DTC) were produced according to our previous report (Table S1) [40]. Mal-PEG-P(TMC-DTC) (200 mg, 8.2 μmol) was added under stirring to 1.5 mL TBP (CGGGHKYLRW, 19.2 mg, 16.4 μmol) solution in N, N-dimethlyformamide (DMF). The reaction proceeded at 37 °C for 24 h, followed by intensive dialysis (MWCO 3500) against 100 mL DMF (× 3) and

Formation and characterization of TBP-Ps-Dox and Tf@TBP-Ps-Dox

TBP-Ps-Dox with three different TBP molar surface densities were obtained from co-assembly of PEG-P(TMC-DTC) and 8.6, 17.2 and 25.8 mol% TBP-PEG-P(TMC-DTC) (referring to total copolymers), followed by Dox·HCl loading using a pH gradient method (Scheme 1A). To make TBP preferentially located at the outer surface of polymersomes facilitating the Tf binding, the PEG in TBP-PEG-P(TMC-DTC) (Mn = 7.5 kg/mol) was designed longer than that in PEG-P(TMC-DTC) (Mn = 5.0 kg/mol) (Table S1). The dynamic

Conclusion

We have demonstrated that disulfide-crosslinked polymersomes functionalized with a transferrin-binding peptide (TBP-Ps) can selectively and stably bind transferrin and subsequently mediate targeted Dox delivery to TfR over-expressing HCT-116 colorectal cancer cells in vitro and in vivo, leading to enhanced tumor suppression and reduced off-target side effects. To the best of our knowledge, this is the first report on the preparation of transferrin-functionalized nanomedicines by selective

Acknowledgements

This work is supported by research grants from the National Natural Science Foundation of China (NSFC 51633005, 51761135117, 51773146, 51861145310, 51561135010).

References (54)

  • A. Wicki et al.

    Nanomedicine in cancer therapy: challenges, opportunities, and clinical applications

    J. Control. Release

    (2015)
  • Y.S. Youn et al.

    Perspectives on the past, present and future of cancer nanomedicine

    Adv. Drug Deliv. Rev.

    (2018)
  • R. van der Meel et al.

    Ligand-targeted particulate nanomedicines undergoing clinical evaluation: current status

    Adv. Drug Deliv. Rev.

    (2013)
  • K.F. Pirollo et al.

    Safety and efficacy in advanced solid tumors of a targeted nanocomplex carrying the p53 gene used in combination with docetaxel: a phase 1b study

    Mol. Ther.

    (2016)
  • A. Siefker-Radtke et al.

    A phase l study of a tumor-targeted systemic nanodelivery system, SGT-94, in genitourinary cancers

    Mol. Ther.

    (2016)
  • L. Liu et al.

    Dihydroartemisinin and transferrin dual-dressed nano-graphene oxide for a pH-triggered chemotherapy

    Biomaterials

    (2015)
  • S.S. Kim et al.

    Encapsulation of temozolomide in a tumor-targeting nanocomplex enhances anti-cancer efficacy and reduces toxicity in a mouse model of glioblastoma

    Cancer Lett.

    (2015)
  • S.S. Kim et al.

    The clinical potential of targeted nanomedicine: delivering to cancer stem-like cells

    Mol. Ther.

    (2014)
  • N. Senzer et al.

    Phase I study of a systemically delivered p53 nanoparticle in advanced solid tumors

    Mol. Ther.

    (2013)
  • A.M. Brinkman et al.

    Aminoflavone-loaded EGFR-targeted unimolecular micelle nanoparticles exhibit anti-cancer effects in triple negative breast cancer

    Biomaterials

    (2016)
  • M. Santi et al.

    Rational design of a transferrin-binding peptide sequence tailored to targeted nanoparticle internalization

    Bioconjug. Chem.

    (2017)
  • H. Makwana et al.

    Engineered polymer-transferrin conjugates as self-assembling targeted drug delivery systems

    Biomacromolecules

    (2017)
  • Y. Zou et al.

    Robust, tumor-homing and redox-sensitive polymersomal doxorubicin: a superior alternative to Doxil and Caelyx?

    J. Control. Release

    (2016)
  • Y. Fang et al.

    EGFR-targeted multifunctional polymersomal doxorubicin induces selective and potent suppression of orthotopic human liver cancer in vivo

    Acta Biomater.

    (2017)
  • Y. Zhu et al.

    cRGD-functionalized reduction-sensitive shell-sheddable biodegradable micelles mediate enhanced doxorubicin delivery to human glioma xenografts in vivo

    J. Control. Release

    (2016)
  • W.J. Yang et al.

    Granzyme B-loaded, cell-selective penetrating and reduction-responsive polymersomes effectively inhibit progression of orthotopic human lung tumor in vivo

    J. Control. Release

    (2018)
  • L. Ding et al.

    HER2-specific reduction-sensitive immunopolymersomes with high loading of Epirubicin for targeted treatment of ovarian tumor

    Biomacromolecules

    (2019)
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