Targeting gold nanoshells on silica nanorattles: a drug cocktail to fight breast tumors via a single irradiation with near-infrared laser light

Sub-picometer level all-solid-state narrow linewidth single-frequency Pr3+:LiYF4 laser in the near-infrared spectral region

We report an all-solid-state near-infrared single-frequency (single longitudinal mode, SLM) Pr3+:LiYF4 (Pr:YLF) laser with the spectral linewidth at the sub-picometer level. The SLM lasers with center wavelengths of 868 and 907 nm are realized in Pr:YLF crystal for the first time to the best of our knowledge. The maximum output powers of SLM lasers at 868 and 907 nm are 102  and 213mW, corresponding to the narrowest spectral linewidths of 82 MHz (0.21 pm) and 94 MHz (0.26 pm), respectively. At the maximum output power, the beam quality factors in the x and y directions are measured as 1.25 and 1.16 at 868 nm and 1.21 and 1.13 at 907 nm, respectively. The output power stabilities of the 868 and 907 nm SLM lasers are calculated as 1.39% and 0.87%, respectively. The successful realization of 868 and 907 nm all-solid-state SLM lasers makes up for the gap that the Pr:YLF SLM lasers developed in the past are focused on the visible region, enriches the types of near-infrared (NIR) SLM lasers, and can provide practical applications in biomedicine, cold atom physics, and optical atom manipulation.

Cu3P/1-MT Nanocomposites Potentiated Photothermal-Immunotherapy

Purpose

Photothermal therapy (PTT) is a promising anticancer treatment that involves inducing thermal ablation and enhancing antitumor immune responses. However, it is difficult to completely eradicate tumor foci through thermal ablation alone. Additionally, the PTT elicited antitumor immune responses are often insufficient to prevent tumor recurrence or metastasis, due to the presence of an immunosuppressive microenvironment. Therefore, combining photothermal and immunotherapy is believed to be a more effective treatment approach as it can modulate the immune microenvironment and amplify the post-ablation immune response.

Methods

Herein, the indoleamine 2, 3-dioxygenase-1 inhibitors (1-MT) loaded copper (I) phosphide nanocomposites (Cu₃P/1-MT NPs) are prepared for PTT and immunotherapy. The thermal variations of the Cu₃P/1-MT NPs solution under different conditions were measured. The cellular cytotoxicity and immunogenic cell death (ICD) induction efficiency of Cu₃P/1-MT NPs were analyzed by cell counting kit-8 assay and flow cytometry in 4T1 cells. And the immune response and antitumor therapeutic efficacy of Cu₃P/1-MT NPs were evaluated in 4T1-tumor bearing mice.

Results

Even at low energy of laser irradiation, Cu₃P/1-MT NPs remarkably enhanced PTT efficacy and induced immunogenic tumor cell death. Particularly, the tumor-associated antigens (TAAs) could help promote the maturation of dendritic cells (DCs) and antigen presentation, which further activates infiltration of CD8⁺ T cells through synergistically inhibiting the indoleamine 2, 3-dioxygenase-1. Additionally, Cu₃P/1-MT NPs decreased the suppressive immune cells such as regulatory T cells (Tregs) and M2 macrophages, indicating an immune suppression modulation effect.

Conclusion

Cu₃P/1-MT nanocomposites with excellent photothermal conversion efficiency and immunomodulatory properties were prepared. In addition to enhanced the PTT efficacy and induced immunogenic tumor cell death, it also modulated the immunosuppressive microenvironment. Thereby, this study is expected to offer a practical and convenient approach to amplify the antitumor therapeutic efficiency with photothermal-immunotherapy.

Two-Stage Targeted Bismuthene-Based Composite Nanosystem for Multimodal Imaging Guided Enhanced Hyperthermia and Inhibition of Tumor Recurrence

A key challenge for nanomedicines in clinical application is to reduce the dose while achieving excellent efficacy, which has attracted extensive attention in dose toxicity and potential risks. It is thus necessary to reasonably design nanomedicine with high-efficiency targeting and accumulation. Here, we designed and synthesized a tetragonal bismuthene-based "all-in-one" composite nanosystem (TPP-Bi@PDA@CP) with two-stage targeting, multimodal imaging, photothermal therapy, and immune enhancement functions. Through the elaborate design of its structure, the composite nanosystem possesses multiple properties including (i) two-stage targeting function of hepatoma cells and mitochondria [the aggregation at the tumor site is 2.63-fold higher than that of traditional enhanced permeability and retention (EPR) effect]; (ii) computed tomography (CT) contrast-enhancement efficiency as high as ∼51.8 HU mL mg^-1 (3.16-fold that of the clinically available iopromide); (iii) ultrahigh photothermal conversion efficiency (52.3%, 808 nm), promising photothermal therapy (PTT), and high-contrast infrared thermal (IRT)/photoacoustic (PA) imaging of tumor; (iv) benefitting from the two-stage targeting function and excellent photothermal conversion ability, the dose used in this strategy is one of the lowest doses in hyperthermia (the inhibition rate of tumor cells was 50% at a dose of 15 μg mL^-1 and 75% at a dose of 25 μg mL^-1); (v) the compound polysaccharide (CP) shell with hepatoma cell targeting and immune enhancement functions effectively inhibited the recurrence of tumor. Therefore, our work reduces the dose toxicity and potential risk of nanomedicines and highlights the great potential as an all-in-one theranostic nanoplatform for two-stage targeting, integrated diagnostic imaging, photothermal therapy, and inhibition of tumor recurrence.

A silk fibroin based bioadhesive with synergistic photothermal-reinforced antibacterial activity

Bioadhesives have gained considerable popularity for application in wound closure. However, applying bioadhesives incurs risks associated with bacterial infection during wound healing. Hence, in this study, a silk fibroin based bioadhesive was constructed via employing natural macromolecule, silk fibroin (SF), to spontaneously coassemble with natural plant polyphenol, tannic acid (TA), and iron oxide nanoparticles (Fe₃O₄ NPs). In the system, the natural macromolecule SF plays a key role in fabricating the macromolecular network matrix due to the change of the secondary structure of SF (from random coil to β-sheet) under the trigger of TA. Importantly, the strong hydrogen bonding interactions between SF and TA, and the coordination bonds between TA and Fe₃O₄ NPs endow the bioadhesive with high extensibility, self-healing properties, and considerable wet adhesion. Meanwhile, the synergy between the inherent photothermal properties of Fe₃O₄ NPs and TA/Fe³⁺ complexes under near-infrared (NIR) radiation enables the bioadhesive superior photothermal-reinforced antibacterial activity. The multifunctional natural macromolecule bioadhesive is a potential candidate in clinical wound management for improved outcomes, especially in infected wounds.

Near infrared triggered chemo-PTT-PDT effect mediated by glioma directed twin functional-chimeric peptide-decorated gold nanoroses

The successful application of nanomedicine against glioma is basically hooked on to the fabrication of specific and efficient glioma targeted multifunctional theranostics. Herein, through an easy synthetic methodology, we fabricated a type of novel multifunctional theranostic nanoplatform comprising of anisotropic gold nanoroses (AuNs) co-loaded with doxorubicin (DOX) and the near-infrared (NIR) active/responsive dye, indocyanine green (ICG). The tailored nanotheranostics upon being exposed to NIR laser helped in achieving combinatorial chemo-phototherapy along with optical cell imaging. BBB/glioma-targeting ability was realized by amalgamating the AuNs with a naive peptide drug with BBB-glioma targeting and anti-glioma twin functionality. Efficacy studies carried out in C6 cells and spheroids demonstrated heightened synergistic glioma chemo-PDT-PTT effect (~85% ablation in C6 cells and ~88% in C6 spheroids) by the AuNDIPs as compared to the individual therapeutic entities. Here, the AuNs derived nanophototheranostics with in force targeting and on-demand drug release nature will further aid in abolishing chemotherapy associated adverse events by adopting a combinatorial approach for synergistic glioma eradication.

Polyoxometalate-Covalent Organic Framework Hybrid Materials for the pH-Responsive Photothermal Tumor Therapy

Photothermal therapy (PTT) has become one of the most effective methods for tumor treatment. With the development of medicine, studies focusing primarily on the therapeutic and diagnostic agents with desirable...

External Basic Hyperthermia Devices for Preclinical Studies in Small Animals

Simple Summary

The application of mild hyperthermia can be beneficial for solid tumor treatment by induction of sublethal effects on a tissue- and cellular level. When designing a hyperthermia experiment, several factors should be taken into consideration. In this review, multiple elementary hyperthermia devices are described in detail to aid standardization of treatment design.

Abstract

Preclinical studies have shown that application of mild hyperthermia (40–43 °C) is a promising adjuvant to solid tumor treatment. To improve preclinical testing, enhance reproducibility, and allow comparison of the obtained results, it is crucial to have standardization of the available methods. Reproducibility of methods in and between research groups on the same techniques is crucial to have a better prediction of the clinical outcome and to improve new treatment strategies (for instance with heat-sensitive nanoparticles). Here we provide a preclinically oriented review on the use and applicability of basic hyperthermia systems available for solid tumor thermal treatment in small animals. The complexity of these techniques ranges from a simple, low-cost water bath approach, irradiation with light or lasers, to advanced ultrasound and capacitive heating devices.

A PdMo bimetallene with precise wavelength adjustment and catalysis for synergistic photothermal ablation and hydrogen therapy of cancer at different depths

By delivering the idea of green and safe hydrogen energy and novel photothermal therapy to the biomedical field, engineering of therapeutic nanomaterials for treatment of major diseases (such as cancer) holds great significance. In this work, a novel PdMo bimetallene was synthesized by a solvothermal reduction method, and it was explored and applied in the field of anti-tumor therapy for the first time. The absorption peak of the PdMo bimetallene can be precisely adjusted in the NIR biological window (700-1350 nm) only by changing the synthesis time. At the same time, it also shows strong light absorption and high photothermal conversion efficiency. Specifically, the photothermal conversion efficiencies at 808 nm, 980 nm and 1064 nm are 43.1%, 51.7% and 69.15%, respectively. Surprisingly, a PdMo bimetallene is an efficient catalyst, which can effectively promote hydrogen production from the hydrolysis of ammonia borane (AB) under acidic and photothermal conditions. Benefitting from these excellent properties, a multifunctional composite nano therapeutic agent (PdMo@AB@HA) was developed via layer-by-layer surface modification with AB and hyaluronic acid (HA). In this way, the synergistic PTT/hydrogen therapy of PdMo@AB@HA composite nanosheets in the NIR-I and NIR-II windows (808 nm, 980 nm, and 1064 nm) on mouse tumor xenografts of different depths was realized. Furthermore, the controlled release of hydrogen, targeted endocytosis, efficient eradication of tumors of different depths and high biosafety were systematically proved in vitro and in vivo. This work not only provides a novel and efficient theranostic nanoplatform for efficient cancer theranostics, but also provides a new strategy for the development of safe and efficient new anti-tumor therapies.

Zwitterion-functionalized hollow mesoporous Prussian blue nanoparticles for targeted and synergetic chemo-photothermal treatment of acute myeloid leukemia

Multifunctional drug delivery systems combining two or more therapies have a wide-range of potential for high efficacy tumor treatment. Herein, we designed a novel hollow mesoporous Prussian blue nanoparticles (HMPBs)-based platform for targeted and synergetic chemo-photothermal treatment of acute myeloid leukemia (AML). The HMPBs were first loaded with the anticancer drugs daunorubicin (DNR) and cytarabine (AraC), and were subsequently coated with polyethylenimine (PEI) through electrostatic adsorption. Then, zwitterionic sulfobetaine (ZS) and CXCR4 antagonist peptide E5 were modified onto the surface of the nanoparticles via covalent bonding to fabricate a nanoplatform (denoted as HMPBs(DNR + AraC)@PEI-ZS-E5). The nanoplatform showed excellent photothermal effects, superior photothermal stability, reduced nonspecific protein adsorption, efficient targeting capability, a constant hydrodynamic diameter and good biocompatibility. Additionally, a laser-responsive drug release pattern was observed. In vitro results indicated that the nanoplatform could achieve active targeting and remarkable chemo-photothermal synergetic therapeutic effects, showcasing its great potential in AML treatment.

Biodegradable iron-coordinated hollow polydopamine nanospheres for dihydroartemisinin delivery and selectively enhanced therapy in tumor cells

As the semisynthetic derivative and active metabolite of the effective anti-malarial drug artemisinin, dihydroartemisinin (DHA) has been investigated as an emerging therapeutic agent for tumor treatment based on the cytotoxicity of free-radicals originating from interactions with ferrous ions. Meanwhile, simultaneously delivering DHA and iron ions to tumors for selectively killing cancer cells is still a great challenge in DHA tumor therapy. Herein, we develop a facile yet efficient strategy based on iron-coordinated hollow polydopamine nanospheres to load DHA (DHA@HPDA-Fe). The as-prepared nanoagent is biodegradable and exhibits controllable release of DHA and Fe ions in tumor microenvironments, resulting in ferrous ion-enhanced production of cytotoxic reactive oxygen species (ROS) by DHA and thus effectively killing the tumor cells. In vivo therapy experiments indicated that the anti-tumor efficacy of DHA@HPDA-Fe was about 3.05 times greater than that of free DHA, and the tumor inhibition ratio was 88.7% compared with the control group, accompanied by negligible side effects, indicating that the proposed nanomedicine platform is promising for anti-tumor applications.

Antimony-Doped Tin Oxide Nanocrystals for Enhanced Photothermal Theragnosis Therapy of Cancers

The doped semiconductor nanocrystal with free holes in valence band exhibits strong near-infrared (NIR) local surface plasmon resonance effects, which is essential for photothermal agents. Herein, the hydrophilic Sb doped SnO₂ nanocrystals were successfully prepared by a simple hydrothermal synthesis method. The doping makes the Sb doped SnO₂ nanocrystals possessing defect structures. Compared with the un-doped SnO₂ nanocrystals, Sb doped SnO₂ nanocrystals exhibit stronger absorption in the NIR region from 500 to 1,100 nm and higher photothermal conversion efficiency (up to 73.6%) which makes the synthesized Sb doped SnO₂ nanocrystals be used as excellent photothermal agents. Importantly, Sb doped SnO₂ nanocrystals can efficiently kill cancer cells both in vitro and in vivo under the irradiation of a 980 nm laser with a power density of 0.6 W cm^–2. In addition, Sb doped SnO₂ nanocrystals can also be served as efficient CT imaging agents owing to the large X-ray attenuation coefficient of tin.

Dual-targeted photothermal agents for enhanced cancer therapy

Photothermal therapy, in which light is converted into heat and triggers local hyperthermia to ablate tumors, presents an inherently specific and noninvasive treatment for tumor tissues. In this area, the development of efficient photothermal agents (PTAs) has always been a central topic. Although many efforts have been made on the investigation of novel molecular architectures and photothermal materials over the past decades, PTAs can cause severe damage to normal tissues because of the poor tumor aggregate ability and high irradiation density. Recently, dual-targeted photothermal agents (DTPTAs) provide an attractive strategy to overcome these problems and enhance cancer therapy. DTPTAs are functionalized with two classes of targeting units, including tumor environment targeting sites, tumor targeting sites and organelle targeting sites. In this perspective, typical targeted ligands and representative examples of photothermal therapeutic agents with dual-targeted properties are systematically summarized and recent advances using DTPTAs in tumor therapy are highlighted.

Defect engineering of 2D BiOCl nanosheets for photonic tumor ablation

Photothermal therapy (PTT) is an emerging technology as a noninvasive therapeutic modality for inducing photonic cancer hyperthermia. However, current photothermal conversion agents suffer from low therapeutic efficiency and single functionality. Engineering crystal defects on the surface or substrate of semiconductors can substantially enhance their optical absorption capability as well as improve their photothermal effects in theranostic nanomedicines. In this study, a specific defect engineering strategy was developed to endow two-dimensional (2D) BiOCl nanosheets with intriguing photothermal conversion performance by creating oxygen vacancies on the surface (O-BiOCl). Importantly, the photothermal performance and photoacoustic imaging capability of the 2D O-BiOCl nanosheets could be precisely controlled by modulating the amounts of oxygen vacancies. The strong Bi-based X-ray attenuation coefficient endowed these nanosheets with the contrast-enhanced computed tomography imaging capability. The high near-infrared-triggered photonic hyperthermia for tumor ablation was systematically demonstrated both in vitro at the cellular level and in vivo for tumor breast cancer mice xenograft models. Based on the demonstrated high biocompatibility of these 2D O-BiOCl nanosheets, this work not only formulates an intriguing 2D photothermal nanoagent for tumor ablation, but also provides an efficient strategy to control the photothermal performance of nanoagents by defect engineering.

The Pimpled Gold Nanosphere: A Superior Candidate for Plasmonic Photothermal Therapy

BACKGROUND

The development of highly efficient nanoparticles to convert light to heat for anti-cancer applications is quite a challenging field of research.

METHODS

In this study, we synthesized unique pimpled gold nanospheres (PGNSs) for plasmonic photothermal therapy (PPTT). The light-to-heat conversion capability of PGNSs and PPTT damage at the cellular level were investigated using a tissue phantom model. The ability of PGNSs to induce robust cellular damage was studied during cytotoxicity tests on colorectal adenocarcinoma (DLD-1) and fibroblast cell lines. Further, a numerical model of plasmonic (COMSOL Multiphysics) properties was used with the PPTT experimental assays.

RESULTS

A low cytotoxic effect of thiolated polyethylene glycol (SH-PEG400-SH-) was observed which improved the biocompatibility of PGNSs to maintain 89.4% cell viability during cytometry assays (in terms of fibroblast cells for 24 hrs at a concentration of 300 µg/mL). The heat generated from the nanoparticle-mediated phantom models resulted in ΔT=30°C, ΔT=23.1°C and ΔT=21°C for the PGNSs, AuNRs, and AuNPs, respectively (at a 300 µg/mL concentration and for 325 sec). For the in vitro assays of PPTT on cancer cells, the PGNS group induced a 68.78% lethality (apoptosis) on DLD-1 cells. Fluorescence microscopy results showed the destruction of cell membranes and nuclei for the PPTT group. Experiments further revealed a penetration depth of sufficient PPTT damage in a physical tumor model after hematoxylin and eosin (H&E) staining through pathological studies (at depths of 2, 3 and 4 cm). Severe structural damages were observed in the tissue model through an 808-nm laser exposed to the PGNSs.

CONCLUSION

Collectively, such results show much promise for the use of the present PGNSs and photothermal therapy for numerous anti-cancer applications.

Gold nanostars-diagnosis, bioimaging and biomedical applications

Gold Nanostars (GNS) have attracted tremendous attention toward themselves owing to their multi-branched structure and unique properties. These state of the art metallic nanoparticles possess intrinsic features like remarkable optical properties and exceptional physiochemical activities. These star-shaped gold nanoparticles can predominantly be utilized in biosensing, photothermal therapy, imaging, surface-enhanced Raman spectroscopy and target drug delivery applications due to their low toxicity and extraordinary optical features. In the current review, recent approaches in the matter of GNS in case of diagnosis, bioimaging and biomedical applications were summarized and reported. In this regard, first an overview about the structure and general properties of GNS were reported and thence detailed information regarding the diagnostic, bioimaging, photothermal therapy, and drug delivery applications of such novel nanomaterials were presented in detail. Summarized information clearly highlighting the superior capability of GNS as potential multi-functional materials for biomedical applications.

Transcatheter Intra-Arterial Infusion Combined with Interventional Photothermal Therapy for the Treatment of Hepatocellular Carcinoma

Background

Photothermal therapy (PTT) has great potential application in the treatment of tumors. However, due to the low penetration of near-infrared light (NIR) and the low concentration of nanomaterials in the tumor site, the application of PTT has been limited.

Purpose

The objective of this study was to investigate the therapeutic effect of transcatheter intra-arterial infusion of lecithin-modified Bi nanoparticles (Bi-Ln NPs) combined with interventional PTT (IPTT) on hepatocellular carcinoma.

Methods

Bi-Ln NPs were prepared by emulsifying the hydrophobic Bi nanoparticles and lecithin, and the photothermal conversion and cytotoxicity of Bi-Ln NPs were then measured by infrared imaging and MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay, respectively. Twenty-four VX2 hepatic carcinoma rabbits were randomly divided into four groups. Rabbits in group A received Bi-Ln NPs by intra-arterial infusion and NIR laser treatment (IA Bi-Ln NPs + Laser), group B received Bi-Ln NPs by intravenous infusion and NIR laser treatment (IV Bi-Ln NPs + Laser), group C received PBS (phosphate buffer saline) via intra-arterial infusion with NIR laser treatment (IA PBS + Laser), group D received PBS via intra-arterial infusion (IA PBS). Transcatheter intra-arterial infusion was conducted by superselective intubation under digital subtraction angiography (DSA) guidance. IPTT was performed by introducing an NIR optical fiber access to the rabbit VX2 hepatic carcinoma under real-time ultrasound guidance. Magnetic resonance imaging (MRI) was performed to evaluate the tumor size. Hematoxylin and eosin (H&E) stain and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) were conducted 7 days after treatment to evaluate the necrosis rate and viability of tumor, respectively.

Results

The Bi-Ln NPs have the advantages of good biological compatibility and high photothermal conversion efficiency. Minimally invasive transcatheter intra-arterial infusion can markedly increase the concentration of Bi-Ln NPs in tumor tissues. IPTT can contribute to the significant improvement in the photothermal efficiency of Bi-Ln NPs. Compared to other groups, the group of IA Bi-Ln NPs + Laser showed a significantly higher tumor inhibition rate (TIR) of 93.38 ± 19.57%, a higher tumor necrosis rate of 83.12 ± 8.02%, and a higher apoptosis rate of (43.26 ± 10.65%) after treatment.

Conclusion

Transcatheter intra-arterial infusion combined with interventional PTT (IPTT) is safe and effective in eradicating tumor cells and inhibiting tumor growth and may provide a novel and valuable choice for the treatment of hepatocellular carcinoma in the future.

Combinatorial discovery of Mo-based polyoxometalate clusters for tumor photothermal therapy and normal cell protection

Molybdenum (Mo)-based polyoxometalate clusters can kill cancer cells selectively by PTT assay and protect the normal cells by scavenging ROS effectively.

Oral Silica Nanoparticles Lack of Neurotoxic Effects in a Parkinson's Disease Model: A Possible Nanocarrier?

Silica nanoparticles (SiO₂-NP) are an option as drug carriers due to their biodegradability, biocompatibility, and capacity to bind themselves to other compounds. However, until now, the effect of these particles on the brain when neurodegeneration occurs is unknown. Hence, this work focused on the in vivo evaluation of the neurotoxic effects of SiO₂-NP when oxidative and inflammation are present during the development of Parkinson's disease. To determine whether SiO₂-NP may act as a non-neurotoxic carrier we evaluated if the intragastric administration (ig) of SiO₂-NP of 150 nm (25, 50 and 100 mg/kg administered for five consecutive days) increased neuronal damage induced with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) administration. SiO₂-NP administration did not further decrease cell viability assessed by MTT reduction, nor increased lipid peroxidation measured by TBARS or TNF α levels in the striatum and the substantia nigra in the MPTP model. Furthermore, we observed no additional reduction in striatal dopamine levels. The present results suggest that SiO₂-NP of 150 nm are suitable nanocarrier for Parkinson's disease drugs without generating any additional damage.

Nanobiomaterials: from 0D to 3D for tumor therapy and tissue regeneration

Nanobiomaterials have attracted tremendous attention in the biomedical field. Especially in the past few years, a large number of low dimensional nanobiomaterials, including 0D nanostructures, 1D nanotubes and 2D nanosheets, were employed for tumor therapy due to their optically triggered tumor therapy effects and drug loading capacities. However, these low dimensional nanobiomaterials cannot support cell adhesion and possess poor tissue regeneration ability, thus they are not suitable for application in regenerative medicine. Three dimensional (3D) nanofiber scaffolds have attracted extensive attention in tissue regeneration, including bone, skin, nerve and cardiac tissues, due to their similar extracellular matrix structures. Additionally, many 3D scaffolds displayed bone and cartilage regeneration abilities. Therefore, to obtain materials with both tumor therapy and tissue regeneration abilities, it is meaningful and necessary to develop 3D nanobiomaterials with multifunctions. In this review, we systematically review the research progress of nanobiomaterials with varied dimensional structures including 0D, 1D, 2D and 3D, as well as evolutional functions from single tumor therapy to simultaneous tumor therapy and tissue regeneration. This review may pave the way for developing an interdisciplinary research of nanobiomaterials in combination of tumor therapy and regenerative medicine.

Recent progress in nanoscale metal-organic frameworks for drug release and cancer therapy

Nanoscale metal-organic frameworks (MOFs) have been widely used as controlled drug delivery vehicles and cancer therapy agents due to their intrinsic superior properties. Scientists have made remarkable achievements in the field of nanomedicine by using the MOFs and MOF-based multifunctional nanomaterials due to the easy synthesis into nanoscale and functionalization. In this review, we highlight the recent progress of nanoscale MOFs as drug delivery vehicles for cancer theranostics. We divide the discussion into three parts. The first and second parts focus on the drug delivery of unmodified MOF and modified MOFs, respectively, while the third part focuses on porphyrin MOFs as photosensitizers for photodynamic therapy. Finally, we conclude by identifying areas of research that we believe will propel the translation and application of MOFs.

Photonic cancer nanomedicine using the near infrared-II biowindow enabled by biocompatible titanium nitride nanoplatforms

Light-activated photoacoustic imaging (PAI) and photothermal therapy (PTT) using the second near-infrared biowindow (NIR-II, 1000-1350 nm) hold great promise for efficient tumor detection and diagnostic imaging-guided photonic nanomedicine. In this work, we report on the construction of titanium nitride (TiN) nanoparticles, with a high photothermal-conversion efficiency and desirable biocompatibility, as an alternative theranostic agent for NIR-II laser-excited photoacoustic (PA) imaging-guided photothermal tumor hyperthermia. Working within the NIR-II biowindow provides a larger maximum permissible exposure (MPE) and desirable penetration depth of the light, which then allows detection of the tumor to the full extent using PA imaging and complete tumor ablation using photothermal ablation, especially in deeper regions. After further surface polyvinyl-pyrrolidone (PVP) modification, the TiN-PVP photothermal nanoagents exhibited a high photothermal conversion efficiency of 22.8% in the NIR-II biowindow, and we further verified their high penetration depth using the NIR-II biowindow and their corresponding therapeutic effect on the viability of tumor cells in vitro. Furthermore, these TiN-PVP nanoparticles were developed as a contrast agent for NIR-II-activated PA imaging both in vitro and in vivo for the first time and realized efficient photothermal ablation of the tumor in vivo within both the NIR-I and NIR-II biowindows. This work not only provides a paradigm for TiN-PVP photothermal nanoagents working in the NIR-II biowindow both in vitro and in vivo, but also proves the feasibility of PAI and PTT cancer theranostics using NIR-II laser excitation.

Prediction of Gold Nanoparticle and Microwave-Induced Hyperthermia Effects on Tumor Control via a Simulation Approach

Hyperthermia acts as a powerful adjuvant to radiation therapy and chemotherapy. Recent advances show that gold nanoparticles (Au-NPs) can mediate highly localized thermal effects upon interaction with laser radiation. The purpose of the present study was to investigate via in silico simulations the mechanisms of Au-NPs and microwave-induced hyperthermia, in correlation to predictions of tumor control (biological endpoints: tumor shrinkage and cell death) after hyperthermia treatment. We also study in detail the dependence of the size, shape and structure of the gold nanoparticles on their absorption efficiency, and provide general guidelines on how one could modify the absorption spectrum of the nanoparticles in order to meet the needs of specific applications. We calculated the hyperthermia effect using two types of Au-NPs and two types of spherical tumors (prostate and melanoma) with a radius of 3 mm. The plasmon peak for the 30 nm Si-core Au-coated NPs and the 20 nm Au-NPs was found at 590 nm and 540 nm, respectively. Considering the plasmon peaks and the distribution of NPs in the tumor tissue, the induced thermal profile was estimated for different intervals of time. Predictions of hyperthermic cell death were performed by adopting a three-state mathematical model, where “three-state” includes (i) alive, (ii) vulnerable, and (iii) dead states of the cell, and it was coupled with a tumor growth model. Our proposed methodology and preliminary results could be considered as a proof-of-principle for the significance of simulating accurately the hyperthermia-based tumor control involving the immune system. We also propose a method for the optimization of treatment by overcoming thermoresistance by biological means and specifically through the targeting of the heat shock protein 90 (HSP90), which plays a critical role in the thermotolerance of cells and tissues.

Interlayer expansion of 2D MoS2 nanosheets for highly improved photothermal therapy of tumors in vitro and in vivo

Interlayer-expanded MoS2 (E-MoS2) nanosheets with an interlayer spacing of 0.94 nm are demonstrated to show an high photothermal conversion efficiency of ∼62%. More importantly, such biocompatible E-MoS2 nanosheets show highly improved photothermal therapy (PTT) of tumors in vitro and in vivo under near-infrared light irradiation.

Recent Advances in Subcellular Targeted Cancer Therapy Based on Functional Materials

Recently, diverse functional materials that take subcellular structures as therapeutic targets are playing increasingly important roles in cancer therapy. Here, particular emphasis is placed on four kinds of therapies, including chemotherapy, gene therapy, photodynamic therapy (PDT), and hyperthermal therapy, which are the most widely used approaches for killing cancer cells by the specific destruction of subcellular organelles. Moreover, some non-drug-loaded nanoformulations (i.e., metal nanoparticles and molecular self-assemblies) with a fatal effect on cells by influencing the subcellular functions without the use of any drug molecules are also included. According to the basic principles and unique performances of each treatment, appropriate strategies are developed to meet task-specific applications by integrating specific materials, ligands, as well as methods. In addition, the combination of two or more therapies based on multifunctional nanostructures, which either directly target specific subcellular organelles or release organelle-targeted therapeutics, is also introduced with the intent of superadditive therapeutic effects. Finally, the related challenges of critical re-evaluation of this emerging field are presented.

Auto-fluorescent polymer nanotheranostics for self-monitoring of cancer therapy via triple-collaborative strategy

Aberrant regulation of angiogenesis supply sufficient oxygen and nutrients to exacerbate tumor progression and metastasis. Taking this hallmark of cancer into account, reported here is a self-monitoring and triple-collaborative therapy system by auto-fluorescent polymer nanotheranostics which could be concurrently against angiogenesis and tumor cell growth by combining the benefits of anti-angiogenesis, RNA interfere and photothermal therapy (PTT). Auto-fluorescent amphiphilic polymer polyethyleneimine-polylactide (PEI-PLA) with positive charge can simultaneously load hydrophobic antiangiogenesis agent combretastatin A4 (CA4), NIR dye IR825 and absorb negatively charged heat shock protein 70 (HSP70) inhibitor (siRNA against HSP70) to construct self-monitoring nanotheranostics (NPICS). NPICS can effectively restrain the expression of HSP70 to reduce their endurance to the IR825-mediated PTT, leading to an enhanced photocytotoxicity. In a xenograft mouse tumor model, NPICS show an effect of inhibition of tumor angiogenesis and also display a highly synergistic anticancer efficacy with NIR laser irradiation. Significantly, based on its inherent auto-fluorescence, PEI-PLA not only serves as the drug carrier, but also as the self-monitor to real-time track NPICS biodistribution and tumor accumulation via fluorescence imaging. Moreover, IR825 endows NPICS could also be used as photoacoustic (PA) agents for in vivo PA imaging. This nanoplatform shows enormous potentials in cancer theranostics.

Biodegradable Poly(amino acid)-Gold-Magnetic Complex with Efficient Endocytosis for Multimodal Imaging-Guided Chemo-photothermal Therapy

Gold complexes can serve as efficient photothermal converters for cancer therapy, but their non-biodegradability hinders clinical bioapplications. Although enormous effort has been devoted, the conventionally adopted synthetic methods of biodegradation are characterized by high cost and complicated procedures, which delay the process of further clinical translation of gold complexes. Here, we report a multifunctional poly(amino acid)-gold-magnetic complex with self-degradation properties for synergistic chemo-photothermal therapy via simple and green chemistry methods. Nanoparticles of ∼3 nm in the biodegradation product were observed in simulated body fluid in 4 days. The biodegradability mainly benefits from the weakened internal electrostatic interaction of the poly(amino acid) by the ions in simulated body fluid. It is demonstrated that the poly(amino acid)-gold-magnetic complex has great cellular endocytosis by taking advantage of the guanidine group in arginine and possesses multimodal imaging and efficient tumor ablation (94%). This study reports a possibility for gold-magnetic complexes composed of poly(amino acid) to serve as a biodegradable nanotherapeutic for clinical applications.

Loading of Indocyanine Green within Polydopamine-Coated Laponite Nanodisks for Targeted Cancer Photothermal and Photodynamic Therapy

The combination of photothermal therapy (PTT) and photodynamic therapy (PDT) in cancer treatment has attracted much attention in recent years. However, developing highly efficient and targeted therapeutic nanoagents for amplifying PTT and PDT treatments remains challenging. In this work, we developed a novel photothermal and photodynamic therapeutic nanoplatform for treatment of cancer cells overexpressing integrin αvβ₃ through the coating of polydopamine (PDA) on indocyanine green (ICG)-loaded laponite (LAP) and then further conjugating polyethylene glycol-arginine-glycine-aspartic acid (PEG-RGD) as targeted agents on the surface. The ICG/LAP⁻PDA⁻PEG⁻RGD (ILPR) nanoparticles (NPs) formed could load ICG with a high encapsulation efficiency of 94.1%, improve the photostability of loaded ICG dramatically via the protection of PDA and LAP, and display excellent colloidal stability and biocompatibility due to the PEGylation. Under near-infrared (NIR) laser irradiation, the ILPR NPs could exert enhanced photothermal conversion reproducibly and generate reactive oxygen species (ROS) efficiently. More importantly, in vitro experiments proved that ILPR NPs could specifically target cancer cells overexpressing integrin αvβ₃, enhance cellular uptake due to RGD-mediated targeting, and exert improved photothermal and photodynamic killing efficiency against targeted cells under NIR laser irradiation. Therefore, ILPR may be used as effective therapeutic nanoagents with enhanced photothermal conversion performance and ROS generating ability for targeted PTT and PDT treatment of cancer cells with integrin αvβ₃ overexpressed.

Yolk-Shell Nanostructures: Design, Synthesis, and Biomedical Applications

Yolk-shell nanostructures (YSNs) composed of a core within a hollow cavity surrounded by a porous outer shell have received tremendous research interest owing to their unique structural features, fascinating physicochemical properties, and widespread potential applications. Here, a comprehensive overview of the design, synthesis, and biomedical applications of YSNs is presented. The synthetic strategies toward YSNs are divided into four categories, including hard-templating, soft-templating, self-templating, and multimethod combination synthesis. For the hard- or soft-templating strategies, different types of rigid or vesicle templates are used for making YSNs. For the self-templating strategy, a number of unconventional synthetic methods without additional templates are introduced. For the multimethod combination strategy, various methods are applied together to produce YSNs that cannot be obtained directly by only a single method. The biomedical applications of YSNs including biosensing, bioimaging, drug/gene delivery, and cancer therapy are discussed in detail. Moreover, the potential superiority of YSNs for these applications is also highlighted. Finally, some perspectives on the future research and development of YSNs are provided.

Two-Dimensional Tantalum Carbide (MXenes) Composite Nanosheets for Multiple Imaging-Guided Photothermal Tumor Ablation

MXenes, an emerging family of graphene-analogues two-dimensional (2D) materials, have attracted continuous and tremendous attention in many application fields because of their intrinsic physiochemical properties and high performance in versatile applications. In this work, we report on the construction of tantalum carbide (Ta₄C₃) MXene-based composite nanosheets for multiple imaging-guided photothermal tumor ablation, which has been achieved by rational choice of the composition of MXenes and their surface functionalization. A redox reaction was activated on the surface of tantalum carbide (Ta₄C₃) MXene for in situ growth of manganese oxide nanoparticles (MnO_x/Ta₄C₃) based on the reducing surface of the nanosheets. The tantalum components of MnO_x/Ta₄C₃ acted as the high-performance contrast agents for contrast-enhanced computed tomography, and the integrated MnO_x component functionalized as the tumor microenvironment-responsive contrast agents for T₁-weighted magnetic resonance imaging. The photothermal-conversion performance of MnO_x/Ta₄C₃ composite nanosheets not only has achieved contrast-enhanced photoacoustic imaging, but also realized the significant tumor-growth suppression by photothermal hyperthermia. This work broadens the biomedical applications of MXenes, not only by the fabrication of family members of biocompatible MXenes, but also by the development of functionalization strategies of MXenes for cancer-theranostic applications.

Targeted Delivery of siRNA with pH-Responsive Hybrid Gold Nanostars for Cancer Treatment

In this work, we report the engineering of gold nanostars (GNS) to deliver small interfering RNA (siRNA) into HepG2 cells. The ligand DG-PEG-Lipoic acid (LA)-Lys-9R (hydrazone) was designed to functionalize GNS, and create the nanoparticles named as 9R/DG-GNS (hydrazone). In the ligand, 2-deoxyglucose (DG) is the targeting molecule, polyethylene glycol (PEG) helps to improve the dispersity and biocompatibility, 9-poly-d-arginine (9R) is employed to provide a positive surface charge and adsorb negative siRNA, and hydrazone bonds are pH-responsive and can avoid receptor-mediated endosomal recycling. Compared to GNS alone, 9R/DG-GNS (hydrazone) showed superior transfection efficiency. The expressions of cyclooxygenase-2 (COX-2) in HepG2 and SGC7901 cells were significantly suppressed by siRNA/9R/DG-GNS (hydrazone) complex. Notably, 9R/DG-GNS (hydrazone) possessed low cytotoxicity even at high concentrations in both normal cells and tumor cells. The combination treatment of siRNA/9R/DG-GNS (hydrazone) complex inhibited the cell growth rate by more than 75%. These results verified that the pH-responsive GNS complex is a promising siRNA delivery system for cancer therapy, and it is anticipated that near-infrared absorbing GNS with good photothermal conversion efficiency can be potentially used for photothermal therapy of tumors.

A Comparative Study of Clinical Intervention and Interventional Photothermal Therapy for Pancreatic Cancer

Although nanoparticle-based photothermal therapy (PTT) has been intensively investigated recently, its comparative efficiency with any clinical cancer treatments has been rarely explored. Herein for the first time we report a systematic comparative study of clinical iodine-125 (¹²⁵ I) interstitial brachytherapy (IBT-125-I) and interventional PTT (IPTT) in an orthotopic xenograft model of human pancreatic cancer. IPTT, based on the nanoparticles composing of anti-urokinase plasminogen activator receptor (uPAR) antibody, polyethylene glycol (PEG), and indocyanine green (ICG) modified gold nanoshells (hereinafter uIGNs), is directly applied to local pancreatic tumor deep in the abdomen. In comparison to IBT-125-I, a 25% higher median survival rate of IPTT with complete ablation by one-time intervention has been achieved. The IPTT could also inhibit pancreatic tumor metastasis which can be harnessed for effective cancer immunotherapy. All results show that this IPTT is a safe and radical treatment for eradicating tumor cells, and may benefit future clinical pancreatic cancer patients.

Au@Void@Ag Yolk-Shell Nanoclusters Visited by Molecular Dynamics Simulation: The Effects of Structural Factors on Thermodynamic Stability

Au@void@Ag yolk-shell nanoclusters were studied by molecular dynamics simulation in order to study the effects of core and shell sizes on their thermodynamic stability and structural transformation. The results demonstrated that all of simulated nanoclusters with different core and shell sizes are unstable at temperatures lower than 350 K in such a way that Ag atoms are collapsed into the void space and fill it, which leads to creation of a more stable core-shell morphology, and at the melting point, only core-shell structures with altered thickness of the shell exist. Also, at higher temperatures, Au atoms tend to migrate toward the surface, and an increase of both the core and shell sizes leads to an increase of the thermodynamic stability. Moreover, a Au₁₄₇@void@Ag₂₅₂ nanocluster with the largest core and shell and minimum void space exhibited the most thermodynamic stability and highest melting point. Generally, the core and shell sizes affect the stability and thermal behavior of yolk-shell nanoclusters cooperatively.

Ternary Chalcogenide Nanosheets with Ultrahigh Photothermal Conversion Efficiency for Photoacoustic Theranostics

2D materials (TDMs) have been explored for photonic theranostics. To achieve deep-tissue penetration, near-infrared (NIR) light is essential for photoacoustic (PA) theranostics. However, because the absorption profiles of existing TDMs are generally featureless with no obvious NIR absorption peaks, their PA signals and therapeutic efficacies are limited. This paper herein reports the synthesis and application of ternary chalcogenide nanosheets (Ta₂ NiS₅ -P) for PA theranostics. In contrast to the current TDMs for such application, Ta₂ NiS₅ -P has a ternary instead of binary composition. This difference brings in the strong and featured NIR for Ta₂ NiS₅ -P. To the best of the knowledge, this is the first example using ternary chalcogenide nanosheets for such application; moreover, the photothermal conversion efficiency of Ta₂ NiS₅ -P is the highest (35%) among all the reported TDMs based on the same calculation method. These advantages allow Ta₂ NiS₅ -P to passively target, effectively delineate, and completely eradicate the tumor of living mice after systemic administration.

Nuclear-Targeted Multifunctional Magnetic Nanoparticles for Photothermal Therapy

The pursuit of multifunctional, innovative, more efficient, and safer cancer treatment has gained increasing interest in the research of preclinical nanoparticle-mediated photothermal therapy (PTT). Cell nucleus is recognized as the ideal target for cancer treatment because it plays a central role in genetic information and the transcription machinery reside. In this work, an efficient nuclear-targeted PTT strategy is proposed using transferrin and TAT peptide (TAT: YGRKKRRQRRR) conjugated monodisperse magnetic nanoparticles, which can be readily functionalized and stabilized for potential diagnostic and therapeutic applications. The monodisperse magnetic nanoparticles exhibit high photothermal conversion efficiency (≈37%) and considerable photothermal stability. They also show a high magnetization value and transverse relaxivity (207.1 mm^-1 s^-1 ), which could be applied for magnetic resonance imaging. The monodisperse magnetic nanoparticles conjugated with TAT peptides can efficiently target the nucleus and achieve the imaging-guided function, efficient cancer cells killing ability. Therefore, this work may present a practicable strategy to develop subcellular organelle targeted PTT agents for simultaneous cancer targeting, imaging, and therapy.

Gold nanoparticles, radiations and the immune system: Current insights into the physical mechanisms and the biological interactions of this new alliance towards cancer therapy

Considering both cancer's serious impact on public health and the side effects of cancer treatments, strategies towards targeted cancer therapy have lately gained considerable interest. Employment of gold nanoparticles (GNPs), in combination with ionizing and non-ionizing radiations, has been shown to improve the effect of radiation treatment significantly. GNPs, as high-Z particles, possess the ability to absorb ionizing radiation and enhance the deposited dose within the targeted tumors. Furthermore, they can convert non-ionizing radiation into heat, due to plasmon resonance, leading to hyperthermic damage to cancer cells. These observations, also supported by experimental evidence both in vitro and in vivo systems, reveal the capacity of GNPs to act as radiosensitizers for different types of radiation. In addition, they can be chemically modified to selectively target tumors, which renders them suitable for future cancer treatment therapies. Herein, a current review of the latest data on the physical properties of GNPs and their effects on GNP circulation time, biodistribution and clearance, as well as their interactions with plasma proteins and the immune system, is presented. Emphasis is also given with an in depth discussion on the underlying physical and biological mechanisms of radiosensitization. Furthermore, simulation data are provided on the use of GNPs in photothermal therapy upon non-ionizing laser irradiation treatment. Finally, the results obtained from the application of GNPs at clinical trials and pre-clinical experiments in vivo are reported.

Surfactant-Free Preparation of Au@Resveratrol Hollow Nanoparticles with Photothermal Performance and Antioxidant Activity

Nanocomposites based on hollow Au nanostructures have gained considerable attention in theranostics applications because of their unique plasmonic structures and attractive physicochemical properties. The exploration of feasible and facile methods for constructing multifunctional nanocomposites combined with bioactive molecules is greatly needed for the development of multifunctional theranostics platforms. In this work, resveratrol, a natural polyphenol with antioxidant activity and cancer-chemopreventive propertyies is employed as the reducing agent cum coating agent for the surfactant-free preparation of Au@resveratrol hollow NPs (Au@Res HNPs). The as-prepared Au@Res HNPs were found to present good photothermal performance and chemical inhibition for cancer therapy. In vitro experiments indicated that the Au@Res HNPs can block cell cycles to inhibit cell division and lead to cell apoptosis after 808-nm laser irradiation. Because no toxic surfactants are introduced, the current protocol avoids the tedious surfactant separation and surface modification processes that are necessary for most theranostics materials.

Enzyme and pH-responsive nanovehicles for intracellular drug release and photodynamic therapy

An enzyme and pH-responsive nanocomposite was constructed for sensitive intracellular drug release and photodynamic therapy (PDT). The novel nanoplatforms provide the potential application in cancer treatment.

AIE luminogen-functionalised mesoporous silica nanoparticles as nanotheranostic agents for imaging guided synergetic chemo-/photothermal therapy

A novel AIE luminogen-functionalised nanotheranostic platform for cell imaging and simultaneous chemo- and photothermal therapies.

Gold-Nanoclustered Hyaluronan Nano-Assemblies for Photothermally Maneuvered Photodynamic Tumor Ablation

Optically active nanomaterials have shown great promise as a nanomedicine platform for photothermal or photodynamic cancer therapies. Herein, we report a gold-nanoclustered hyaluronan nanoassembly (GNc-HyNA) for photothermally boosted photodynamic tumor ablation. Unlike other supramolecular gold constructs based on gold nanoparticle building blocks, this system utilizes the nanoassembly of amphiphilic hyaluronan conjugates as a drug carrier for a hydrophobic photodynamic therapy agent verteporfin, a polymeric reducing agent, and an organic nanoscaffold upon which gold can grow. Gold nanoclusters were selectively installed on the outer shell of the hyaluronan nanoassembly, forming a gold shell. Given the dual protection effect by the hyaluronan self-assembly as well as by the inorganic gold shell, verteporfin-encapsulated GNc-HyNA (Vp-GNc-HyNA) exhibited outstanding stability in the bloodstream. Interestingly, the fluorescence and photodynamic properties of Vp-GNc-HyNA were considerably quenched due to the gold nanoclusters covering the surface of the nanoassemblies; however, photothermal activation by 808 nm laser irradiation induced a significant increase in temperature, which empowered the PDT effect of Vp-GNc-HyNA. Furthermore, fluorescence and photodynamic effects were recovered far more rapidly in cancer cells due to certain intracellular enzymes, particularly hyaluronidases and glutathione. Vp-GNc-HyNA exerted a great potential to treat tumors both in vitro and in vivo. Tumors were completely ablated with a 100% survival rate and complete skin regeneration over the 50 days following Vp-GNc-HyNA treatment in an orthotopic breast tumor model. Our results suggest that photothermally boosted photodynamic therapy using Vp-GNc-HyNA can offer a potent therapeutic means to eradicate tumors.

Near-Infrared Organic Dye-Based Nanoagent for the Photothermal Therapy of Cancer

Given their easy structural modification and good biocompatibility advantages, near-infrared (NIR) organic dyes with a large molar extinction coefficient, while a superlow fluorescence quantum yield shows considerable potential application in photothermal therapy (PTT). Herein, a new NIR-absorbing asymmetric cyanine dye, namely, RC, is designed and synthesized via the hybrid of rhodamine and hemicyanine derivatives. RC-BSA nanoparticles (NPs) are fabricated by using the bovine serum albumin (BSA) matrix. The NPs exhibit a strong NIR absorption peak at ∼868 nm and 28.7% photothermal conversion efficiency. Based on these features, RC-BSA NPs exhibit excellent performance in ablating tumor under a 915 nm laser radiation through a PTT mechanism. These NPs show no obvious toxicity to the treated mice. Thus, RC-BSA NPs can used as a new NIR laser-triggered PTT agent in cancer treatment.

Gold-Nanosponge-Based Multistimuli-Responsive Drug Vehicles for Targeted Chemo-Photothermal Therapy

Gold-nanosponge-based multistimuli-responsive drug vehicles are constructed for combined chemo-photothermal therapy with pinpointed drug delivery and release capabilities and minimized nonspecific systemic spread of drugs, remarkably enhancing the therapeutic efficiency while minimizing acute side effects.

Metal-Organic-Framework-Derived Mesoporous Carbon Nanospheres Containing Porphyrin-Like Metal Centers for Conformal Phototherapy

Mesoporous carbon nanospheres containing porphyrin-like metal centers (denoted as "PMCS") are successfully synthesized by the pyrolysis of an imidazolate framework using a mesoporous-silica protection strategy. The PMCS allow infrared and photoacoustic imaging and synergetic photothermal therapy/photodynamic therapy derived from the porphyrin-like moieties, offering the possibility of real-time monitoring of therapeutic processes and image-guided precise conformal phototherapy. PMCS thus represent a novel multifunctional theranostic platform for improved treatment efficiencies.