Tumor microenvironment penetrating chitosan nanoparticles for elimination of cancer relapse and minimal residual disease

Abstract

Chitosan and its derivatives are among biomaterials with numerous medical applications, especially in cancer. Chitosan is amenable to forming innumerable shapes such as micelles, niosomes, hydrogels, nanoparticles, and scaffolds, among others. Chitosan derivatives can also bring unprecedented potential to cross numerous biological barriers. Combined with other biomaterials, hybrid and multitasking chitosan-based systems can be realized for many applications. These include controlled drug release, targeted drug delivery, post-surgery implants (immunovaccines), theranostics, biosensing of tumor-derived circulating materials, multimodal systems, and combination therapy platforms with the potential to eliminate bulk tumors as well as lingering tumor cells to treat minimal residual disease (MRD) and recurrent cancer. We first introduce different formats, derivatives, and properties of chitosan. Next, given the barriers to therapeutic efficacy in solid tumors, we review advanced formulations of chitosan modules as efficient drug delivery systems to overcome tumor heterogeneity, multi-drug resistance, MRD, and metastasis. Finally, we discuss chitosan NPs for clinical translation and treatment of recurrent cancer and their future perspective.

Keywords: chitosan; drug delivery; minimal residual disease; recurrent cancer; tumor heterogeneity; tumor microenvironment.

Figure 1

Chitosan NPs afford effective gene therapy and endo/lysosomal escape. (A) Bioinspired glycol chitosan NPs for GI passing and endosomal escape delivery of oral siRNA for successful treatment of CLM. (a) Synthesis and characterization of AR-GT NPs. (b) Ex vivo fluorescence images of major organs of the AR-coated chitosan and glycol chitosan (GC)-coated NPs in treated animals for 30 min. (c) In vivo mechanism of AR-GT100 transport, which is designed to occur through transcytosis, inspired from enterocytic-mediated recycling of amphipathic fatty acid bilirubin, with specific accumulation in the ileum. For chitosan, this occurs through tight junctions. (d) Therapeutic efficacy in a CLM cancer mouse model after oral delivery of AR-chitosan and AR-GT100 (25 or 100 μg/kg) and CLM lung antimetastatic potential. Reprinted with permission from (24), Copyright (2017), American Chemical Society. (B) Chitosan NPs for precisely targeting POLR2A as a therapeutic strategy for human triple-negative breast cancer. (a) Scheme for NP synthesis. (b) TEM images showing pH-responsive NPs and nanobomb effect that occur under low pH 5.0–6.0 endolysosomes, leading to NP enlargement and cracking. At the same time, spherical core–shell NPs are intact under pH 7.4. (c) Endosomal escape of Dextran-Rhodamine (Dex-Rho) NPs. In early hours, the red color largely overlapped with LysoTracker green fluorescence. After 6 h, this overlap is minimum, indicating successful endosomal escape of core–shell chitosan-loaded anti-Mir21 due to the nanobomb effect. Reprinted from (25) Under Creative commons Attribution License 4.0, Copyright (2018) Springer Nature. (C) pH-responsive chitosan-based nanocomplex for efficient CRISPR/Cas9 gene-chemo synergistic HCC therapy. (a) Schematics of preparation and characterizations of CLPV NPs. (b) (i) Working principle of CLPV NPs for precise targeting of VEGFR2 and downstream tumorigenic pathways IL-6/IL-8-NF-κB p65; (ii) T7E1 analysis of the VEGFR2 sgRNA sites on tumor tissues. (c) (i) Plasmid profile of recombinant sgVEGFR2/Cas9 (VC); (ii) AFM image of 238.2-nm CLPV NPs; (iii) agarose gel electrophoresis analysis for VC stability on NPs. (d) In vivo biodistribution studies using injected free cy5.5 and cy5.5-loaded CLPV NPs recorded at different time points from the major organs and tumor tissues. Reprinted with permission from (26), Copyright (2018) Elsevier.

Figure 2

Chitosan-based drug delivery systems for cancer targeting. (A) Nanofiber-based chitosan hydrogel as injectable drug depot. Reprinted from (65) under Creative Commons Attribution License 4.0, Copyright (2021) Wiley‐VCH GmbH. (B) Amphipathic chitosan can self-assemble into vesicular core–shell particles. Reprinted with permission from (66), Copyright (2021) Elsevier. (C) Chitosan hydrogel as a packaging system for other NPs (niosome in hydrogel). Reprinted from (23) under Creative Commons Attribution License 4.0, Copyright (2020) Springer Nature.

Figure 3

Chitosan-based multitasking drug delivery systems for treatment of MDR cancer. (A) Chitosan-based multimodal system for PTT-enhanced PDT therapy. Reprinted with permission from (36), Copyright (2020) Elsevier. (B) Chitosan MN patches for combined chemo-PTT cancer therapy. Reprinted with permission from (37), Copyright (2020) Elsevier. (C) Chitosan-based theranostics for thermal-photoacoustic (PA) imaging-guided tumor chemo-PTT therapy. (a) Schematic of NP working design. (b) Electron microscopy images: (A) TEM and (B) SEM images of HMSNs. TEM image of (C) CuS nanodots (D) and HMSNs-CS-DOX@CuS. Red arrows indicate the CuS nanodots on the HMSN surfaces. Reprinted with permission from (38), Copyright (2021) Elsevier.

Figure 4

N-substitution of chitosan by different approaches.

Figure 5

N-substitution of chitosan by different approaches.

Figure 6

Chitosan NPs affords crossing stroma and biological membranes. (A) EPR and CPP-mediated active targeting. Reprinted from (15) under Creative Commons Attribution License 4.0, Copyright (2019) Springer Nature. (B) FC affords superior mucoadhesion potential to cross epithelial barriers of bladder cancer. Reprinted with permission from (80), Copyright (2021) Wiley‐VCH GmbH. (C) Multi-stage acting CS NPs. Reprinted with permission from (81), Copyright (2019) American Chemical Society. (D) Stroma cell depletion afforded by chitosan-modified CAF inhibitor. Reprinted with permission from (74), Copyright (2018) Elsevier. (E) Chitosan nanosweeper for ECM drilling. Reprinted with permission from (82), Copyright (2018) Elsevier. (F) Chitosan-clocked NPs with RBC membrane as Trojan system. Reprinted from (83), Copyright (2017) American Chemical Society.

Figure 7

Advanced chitosan-based NPS target tumor hypoxia and result in complete tumor remission. (A) Hypoxia alleviation strategy. Schematics of thermo-triggered in situ chitosan gel formation for repeated and enhanced SDT after a single injection. Reprinted with permission from (100), Copyright (2020) Wiley‐VCH GmbH. (B) Hypoxia depletion therapy coupled with hypoxia-activated prodrugs (HAPs). Reprinted with permission from (109), Copyright (2021) Elsevier. (C) Hypoxia-responsive immunomodulation of DCs for boosted PDT coupled immunotherapy. (a) Schematic design of NPs, (b) working principle. (c, d) TEM images of CAGE without and with CpG ODN. (e) The efficacy of antitumor effects in vivo. Reprinted with permission from (110), Copyright (2019) American Chemical Society. (D) Combination of tumor infarction therapy with chemotherapy for tumor starvation therapy. (a) Schematic design of NPs and (b) their working principle. Reprinted with permission from (111), Copyright (2021) Springer Nature.

Figure 8

Chitosan-based platforms for active immunotherapy and metastasis inhibition. (A) Chitosan NPs for NK cell preservation and delivery. Reprinted from (119) under Creative Commons Attribution License 4.0, Copyright (2020) WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim. (B) Integration of chitosan Ch/γ-PGA NPs with radiotherapy boost immune response and elicit antimetastatic potential. Reprinted with permission from (120), Copyright (2020) Elsevier. (C) Chitosan NP-loaded MN patch for systemic vaccination in mice. (a) Schematics of synthesis of CS–OVA–CpG NPs; (b) TEM; (c) macroscopic and SEM images; (d) dissolution kinetics, insertion, and biocompatibility in BALB/c mouse skins; and (e) rat skin. Reproduced with permission from (121), Copyright (2020) Royal Society of Chemistry.

Figure 9

Strategies for CSC targeting and elimination. (A) Hyperbaric oxygen therapy. Reprinted with permission from (92), Copyright (2021) Elsevier. (B) NP surface modification from hydrophilic (TTMA) to highly hydrophobic (C10) tested, with C6 AuNP robustly promoted CSC differentiation by reducing stemness marker. Reprinted with permission from (128), Copyright (2020) American Chemical Society. (C) Multimodal system combines chemo- and cryoablation therapy. Reprinted with permission from (129), Copyright (2021) Elsevier. (D) Receptor-mediated dual drug combination strategy. Reprinted with permission from (130), Copyright (2021) Royal Society of Chemistry.

Figure 10

CS-based liquid biopsy for interrogation and elimination of circulating materials. Chitosan-based microfluidic platform for tumor-derived exosome isolation and analysis. Reprinted from (135), Copyright (2021) Royal Society of Chemistry.

Figure 11

Local injectable chitosan serves as a drug depot to control tumor relapse. Intratumoral injectable chitosan nanoformulation for combined chemo- and immunotherapy of cancer. Reprinted with permission from (139), Copyright (2021) Elsevier.

Figure 12

Post-surgery chitosan injectable gels/implanted scaffolds for treating recurrent cancer and MRD. (A) Magnetic hydrogel for the treatment of breast cancer metastasis. (a) Schematics of design (top) and transformation mechanism (bottom) of GC-ferrofluids to form a magnetic hydrogel. (b) TEM and (c) SEM images of porous magnetic hydrogels. Reprinted from (141) with permission, Copyright (2019) WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim. (B) Injectable biodegradable hydrogel for multiple tumor and recurrent cancer therapy. (a) Schematic for the degradable process of the CS@CuNPs@BPNSs hydrogel. (b) TEM image (c) and efficacy of CuNPs@BPNSs for complete tumor remission in the lung cancer recurrence model. Reprinted from (142) with permission, Copyright (2021) Elsevier. (C) Thermosensitive injectable halloysite-chitosan hydrogels as drug carriers for inhibition of breast cancer recurrence and tissue reconstruction. (a) Synthesis procedure for thiolated halloysite nanotubes (HNT) for DOX loading and hydrogel formation by cross-linking with chitosan through SS bonds and electrostatic interactions. Reprinted from (20) with permission, Copyright (2021) Elsevier. (D) Anti-inflammatory and antibacterial catecholic chitosan hydrogel for rapid surgical trauma healing and subsequent prevention of breast tumor recurrence. (a) Synthesis route of CSG/Fe⁺³/DOX hydrogel by Fe⁺³ chelation of chitosan (CS)–gallic acid (GA) and DOX loading. (b) hemostatic potential in a model of rat liver bleeding, (c) typical bloody filter papers. (d) pH/NIR-responsive DOX (e) Effective 4T1 tumor recurrence of the CSG/Fe3+/DOX hydrogel. Reprinted from (63) with permission. Copyright (2020) Elsevier. (E) 3D printed intelligent scaffold (IS) stops bleeding and adsorbs CTC after surgery to prevent recurrence and distal metastasis of breast cancer. (a) Electro-hydrodynamic jet 3D printing process of drug-loaded chitosan–gelatin (CG) scaffold, (b) macroscopic, (c) microscopic, (d) SEM images of implanted IS after 30 days, (e) potential of IS for wound healing and closure compared to gauze (control) and PLGA-DOX-5FU (PD5) scaffold, (f) potential of IS for recurrent cancer and inhibiting breast cancer lung metastatic activity. From (144), Copyright (2020) Under Creative Commons Attribution License 4.0. ivyspring.