Small gold nanorods laden macrophages for enhanced tumor coverage in photothermal therapy

Synthesis of Small Gold Nanorods and Their Subsequent Functionalization with Hairpin Single Stranded DNA

Small gold nanorods have a significantly large absorption/scattering ratio and are especially beneficial in exploiting photothermal effects, for example in photothermal therapy and remote drug release. This work systematically investigates the influence of growth conditions on the size, growth yield, and stability of small gold nanorods. The silver-assisted seed-mediated growth method was optimized to synthesize stable small gold nanorods with a high growth yield (>85%). Further study on the influence of silver ions on the growth facilitates the growth of small gold nanorods with tunable longitudinal surface plasmon resonance from 613 to 912 nm, with average dimensions of 13-25 nm in length and 5-6 nm in diameter. Moreover, the small gold nanorods were successfully functionalized with thiol-modified hairpin oligonucleotides (hpDNA) labeled with Cy5. Fluorescence intensity measurements show an increase in the presence of target DNA and an enhanced signal/background ratio when the longitudinal surface plasmon resonance of small gold nanorods overlaps with the excitation and emission wavelength of Cy5. This coincides with a reduced fluorescence lifetime of Cy5 in the hairpin structure, indicating surface plasmon resonance-enhanced energy transfer to the small gold nanorods. This study may provide insight on the synthesis and functionalization of small gold nanorods in biomedical sensing and therapy.

Near-Infrared Fluorescent Endoscopic Image-Guided Photothermal Ablation Therapy of Colorectal Cancer Using Dual-Modal Gold Nanorods Targeting Tumor-Infiltrating Innate Immune Cells in a Transgenic TS4 CRE/APC loxΔ468 Mouse Model

Colorectal cancer (CRC) is diagnosed with colonoscopy and treated with focal therapies. CRC is a good candidate for nanoparticle-mediated photothermal ablation (PTA) therapy. Herein, we developed a near-infrared fluorescent (NIRF) endoscopic image-guided PTA approach using a nanoparticle capable of simultaneously diagnosing and treating CRC. Dual-modal NIR heating and fluorescent gold nanorods (dual-modal GNRs) were synthesized by conjugation of GNRs to an NIRF probe. To validate the translational potential of our approach, a well-characterized transgenic TS4 CRE/APC ^loxΔ468 colon cancer mouse model was used to carry out NIRF image-guided PTA using our dual-modal GNRs under clinically relevant conditions. Intravenously infused dual-modal GNRs were effectively targeted at colon polyps by immunogenic capturing of the GNRs within tumor-infiltrating innate immune cells. NIRF endoscopic image-guided PTA using the GNRs permitted successful detection and ablation of inflammatory colon polyps. NIRF endoscopy image-guided PTA using dual-modal GNRs can be utilized for diagnosis and treatment of CRC and various inflammatory diseases.

IR780-based light-responsive nanocomplexes combining phase transition for enhancing multimodal imaging-guided photothermal therapy

Near-infrared (NIR) light-triggered photothermal therapy (PTT) has been widely applied for treating cancer. The combination of nanotechnology and NIR has shown great promise for promoting the efficacy of PTT. However, PTT alone could not completely ablate the tumors and easily causes tumor recurrence. To overcome this challenge, many studies have been performed to enhance PTT, including combining chemical therapy and radiotherapy, both of which have side effects on the body. To reduce the side effects and enhance PTT, a new infrared IR780-based nanocomplex combining liquid fluorocarbon perfluoropentane (PFP) has been synthesized for enhancing multimodal imaging-guided PTT. Under NIR irradiation, the size changes of PFP-loaded nanobubbles transforming into microbubbles allow ultrasound (US) imaging, showing boundaries and internal information of tumors. The breakup process and cascade reaction of phase transition can improve intratumoral permeation and retention of nanoparticles in nonmicrovascular tissue and damage the cell membranes of tumors, further enhancing PTT to kill tumor cells. The strong absorption in the NIR field of IR780-loaded NPs allows not only photoacoustic (PA) imaging but also NIR fluorescence (NIRF) imaging, which provides more anatomical information about tumors. This nanocomplex exhibits good biocompatibility and nontoxicity, strong PA/US/NIRF imaging contrast, excellent liquid-gas transition and a photothermal effect. This finding provides a new method to enhance multimodal imaging-guided cancer nanotheranostics.

Chitosan for gene delivery: Methods for improvement and applications

Gene therapy is a promising strategy for treating challenging diseases. The successful delivery of genes is a critical step for gene therapy. However, concerns about immunogenicity and toxicity are the main obstacles against the widespread use of effective viral systems. Therefore, nonviral vectors are regarded as good alternatives to viral vectors. Chitosan is a natural cationic polysaccharide that could be used to create nonviral gene delivery vectors. Various methods have been developed to improve the properties of chitosan related to gene delivery. This review introduces the features of chitosan in gene delivery, summarizes current progress toward methods promoting the properties of chitosan related to gene delivery, and presents different applications of chitosan in gene delivery vectors. Finally, future prospects of gene vectors based on chitosan are discussed.

Crushed Gold Shell Nanoparticles Labeled with Radioactive Iodine as a Theranostic Nanoplatform for Macrophage-Mediated Photothermal Therapy

Plasmonic nanostructure-mediated photothermal therapy (PTT) has proven to be a promising approach for cancer treatment, and new approaches for its effective delivery to tumor lesions are currently being developed. This study aimed to assess macrophage-mediated delivery of PTT using radioiodine-124-labeled gold nanoparticles with crushed gold shells (¹²⁴I-Au@AuCBs) as a theranostic nanoplatform. ¹²⁴I-Au@AuCBs exhibited effective photothermal conversion effects both in vitro and in vivo and were efficiently taken up by macrophages without cytotoxicity. After the administration of ¹²⁴I-Au@AuCB-labeled macrophages to colon tumors, intensive signals were observed at tumor lesions, and subsequent in vivo PTT with laser irradiation yielded potent antitumor effects. The results indicate the considerable potential of ¹²⁴I-Au@AuCBs as novel theranostic nanomaterials and the prominent advantages of macrophage-mediated cellular therapies in treating cancer and other diseases.

Macrophages-Mediated Delivery of Small Gold Nanorods for Tumor Hypoxia Photoacoustic Imaging and Enhanced Photothermal Therapy

Macrophage-mediated delivery of drugs or nanoparticles has great potential in cancer treatment because it can avoid interception by the immune system and cross the blood-vessel barriers to reach the hypoxic regions of tumors. However, macrophage-based delivery system still faces some great challenges such as low theranostics agent loading capacity and hypoxic regions tendency in vivo. Herein, small gold nanorods (AuNRs) were used as the model theranostics agent to design a macrophage-mediated delivery system with high loading quantity for tumor hypoxia photoacoustic (PA) imaging and enhanced photothermal therapy (PTT). AuNRs modified with various thiolated poly(ethylene glycol)s (HS-PEG) via ligand exchange were investigated for toxicity and cell uptake by macrophages. The tumor hypoxic regions tendency of macrophage-loaded Anionic-AuNRs (Anionic-AuNRs@RAW) were verified by in vivo PA imaging and tumor sections. In vivo systemic PTT demonstrated enhanced tumor inhibition of anionic-AuNRs@RAW. This macrophage-mediated delivery system with high loading capacity could be used to enhance the effectiveness of cancer treatment.

Near-Infrared-Triggered Photodynamic, Photothermal, and on Demand Chemotherapy by Multifunctional Upconversion Nanocomposite

In an attempt to integrate photodynamic therapy (PDT) with photothermal therapy and chemotherapy for enhanced anticancer activity, we have rationally synthesized a multifunctional upconversion nanoplatform using NaYF₄:Yb/Tm/Er/Fe nanoparticles (NPs) as the core and NaYbF₄:1% Tm as a shell. The as-synthesized core-shell upconversion (CSU) NPs exhibited diverse and enhanced photoluminescence emissions in a wide range (UV to NIR) consequent upon Fe³⁺ doping in the core and fabrication of an active shell. Subsequently, CSU was first decorated with titania NPs as photosensitizers. Next, the mesoporous silica (MS) shell loaded with doxorubicin (DOX) via a photocleavable Ru complex as the gating molecule was developed around titania-containing CSU. Finally, gold nanorods (GNRs) with localized surface plasmon resonance (LSPR) at 800 nm were incorporated around the MS layer to obtain the multifunctional nanoplatform. We demonstrated that the UV, blue, and NIR emissions from the CSU produced ROS-mediated PDT through titania activation, induced DOX release through photocleavage of the Ru complex, and generated hyperthermia by LSPR activity of GNRs, respectively, upon a single NIR excitation through FRET. The therapeutic efficacy was validated on HeLa cell lines in vitro by various microscopic and biochemical studies under a significantly milder NIR irradiation and lower dosage of the nanoplatforms, which have been further demonstrated as diagnostic nanoprobes for cell imaging.

Microgels in biomaterials and nanomedicines

Microgels are colloidal particles with crosslinked polymer networks and dimensions ranging from tens of nanometers to micrometers. Specifically, smart microgels are fascinating capable of responding to biological signals in vivo or remote triggers and making the possible for applications in biomaterials and biomedicines. Therefore, how to fundamentally design microgels is an urgent problem to be solved. In this review, we put forward our important fundamental opinions on how to devise the intelligent microgels for cancer therapy, biosensing and biological lubrication. We focus on the design ideas instead of specific implementation process by employing reverse synthesis analysis to programme the microgels at the original stage. Moreover, special insights will be, for the first time, as far as we know, dedicated to the particles completely composed of DNA or proteins into microgel systems. These are discussed in detail in this review. We expect to give readers a broad overview of the design criteria and practical methodologies of microgels according to the application fields, as well as to propel the further developments of highly interesting concepts and materials.

Photothermal therapy and photoacoustic imaging via nanotheranostics in fighting cancer

The nonradiative conversion of light energy into heat (photothermal therapy, PTT) or sound energy (photoacoustic imaging, PAI) has been intensively investigated for the treatment and diagnosis of cancer, respectively. By taking advantage of nanocarriers, both imaging and therapeutic functions together with enhanced tumour accumulation have been thoroughly studied to improve the pre-clinical efficiency of PAI and PTT. In this review, we first summarize the development of inorganic and organic nano photothermal transduction agents (PTAs) and strategies for improving the PTT outcomes, including applying appropriate laser dosage, guiding the treatment via imaging techniques, developing PTAs with absorption in the second NIR window, increasing photothermal conversion efficiency (PCE), and also increasing the accumulation of PTAs in tumours. Second, we introduce the advantages of combining PTT with other therapies in cancer treatment. Third, the emerging applications of PAI in cancer-related research are exemplified. Finally, the perspectives and challenges of PTT and PAI for combating cancer, especially regarding their clinical translation, are discussed. We believe that PTT and PAI having noteworthy features would become promising next-generation non-invasive cancer theranostic techniques and improve our ability to combat cancers.

Disturbance of adhesomes by gold nanoparticles reveals a size- and cell type-bias

Gold nanoparticles (AuNP) have been thoroughly studied as multifunctional theranosis agents for cell imaging and cancer therapy as well as sensors due to their tunable physical and chemical properties. Although AuNP have proved to be safe in a wide concentration range, yet other important biological effects can arise in the sublethal window of treatment. This is especially pivotal to understand how AuNP can affect cell biology when labeling steps are needed for cell tracking in vivo, as nanoparticle loading can affect cell migratory/invasion ability, a function mediated by filamentous actin-rich nanometric structures collectively called adhesomes. It is noteworthy that, although numerous research studies have addressed the cell response to AuNP loading, yet none of them focuses on adhesome dynamics as a target of intracellular pathways affected by AuNP. We intend to study the collective dynamics of adhesive F-actin rich structures upon AuNP treatment as an approach to understand the complex AuNP-triggered modulation of migration/invasion related cellular functions. We demonstrated that citrate-coated spherical AuNP of different sizes (3, 11, 16, 30 and 40 nm) disturbed podosome-forming rosettes and the resulting extracellular matrix (ECM) degradation in a murine macrophage model depending on core size. This phenomenon was accompanied by a reduction in metalloproteinase MMP2 and an increment in metalloproteinase inhibitors, TIMP-1/2 and SerpinE1. We also found that AuNP treatment has opposite effects on focal adhesions (FA) in endothelial and mesenchymal stem cells. While endothelial cells reduced their mature FA number and ECM degradation rate upon AuNP treatment, mouse mesenchymal stem cells increased the number and size of mature FA and, therefore, the ECM degradation rate. Overall, AuNP appear to disturb adhesive structures and therefore migratory/invasive cell functions measured as ECM degradation ability, providing new insights into AuNP-cell interaction depending on cell type.

Macrophages as delivery vehicles for anticancer agents

The delivery of anticancer agents via passive approaches such as the enhanced permeability and retention effect is unlikely to achieve sufficient concentrations throughout the tumor volume for effective treatment. Cell-based delivery approaches using tumor tropic cells have the potential to overcome the limitations of passive approaches. Specifically, this review focuses on the use of monocytes/macrophages for the delivery of a variety of anticancer agents, including nanoparticles, chemotherapeutics and gene constructs. The efficacy of this delivery approach, both as monotherapy and in combination with light-based phototherapy modalities, has been demonstrated in numerous in vitro and animal studies, however, its clinical potential remains to be determined.

Transforming Weakness into Strength: Photothermal-Therapy-Induced Inflammation Enhanced Cytopharmaceutical Chemotherapy as a Combination Anticancer Treatment

A new synergistic treatment that combines photothermal therapy (PTT) and inflammation-mediated active targeting (IMAT) chemotherapy based on cytopharmaceuticals is developed. During PTT, the photothermal tumor ablation is accompanied by an inflammatory effect and upregulation of inflammatory factors at the tumor site, which may accelerate tumor regeneration. Moreover, PTT-induced inflammation can also recruit neutrophils (NEs) to the tumor site. To convert the disadvantages of PTT-induced inflammation into strengths, NEs are investigated as cytopharmaceuticals for IMAT chemotherapy to further inhibit the tumor recurrence after PTT due to the chemotaxis of NEs to the inflammatory sites. In this study, PEGylated gold nanorods (PEG-GNRs) are explored as the photothermal agent and paclitaxel-loaded cytopharmaceuticals of NEs as the IMAT chemotherapeutic agent. PTT is conducted at 72 h postinjection of PEG-GNRs, followed by cytopharmaceuticals for IMAT chemotherapy. It is demonstrated that the cytopharmaceuticals effectively accumulate in the tumor sites after PTT, which leads to a significant enhancement of antitumor efficacy and a reduction in systemic toxicity. These studies suggest that PTT-induced inflammation further enhances the chemotherapy of cytopharmaceuticals, and the combination of PTT and IMAT chemotherapy may be a promising synergistic strategy for targeted cancer therapy.

Polychromatic and polarized multilevel optical data storage

Optical multiplexing is of great importance in information processing, and offers the opportunity to dramatically increase the capacity of information systems. For example, multiplexing among different physical dimensions of light is regarded as an efficient means to substantially increase the capacity of optical data storage (ODS). Alternatively, the capacity can also be increased by multilevel coding. In this paper, we report on the combination of multiplexing among multiple physical dimensions and multilevel coding simultaneously to dramatically boost the capacity of ODS. The physical mechanism relies on the excitation power dependent thermal reshaping of the ODS medium mediated by wavelength and polarization sensitive random hot spots in a volume of coupled disordered gold nanorods (GNRs). The resulting electric field intensity varies drastically inside the focus spot of a laser beam when different combinations of polarization and wavelength are used. Therefore, different hot spots can be selectively activated and encoded by controlling the power of the recording beam, facilitating the realization of the polychromatic and polarized multiplexing of multilevel coding in the disordered plasmonic structure. Our results might find applications in high capacity optical data storage, watermarking, etc.

Synthesis and evaluation of the antiproliferative efficacy of BRM270 phytocomposite nanoparticles against human hepatoma cancer cell lines

BRM270 is the most leading phytochemical extract that possesses potent anticancer properties. A major challenge associated with this drug is its low bioavailability and thus requires high dosages for cancer treatment. Here, we report the novel nano-synthesis of phyto-composite, BRM270 for the first time by mechanical milling method with specific modifications for enhanced cytotoxicity against HepG2 human hepatoma cancer cells. Unlike free BRM270 and other phytomedicines, BRM270 nanoparticles (BRM270 NPs) are well-dispersed and small sized (23 to 70 nm) which is believed to greatly enhanced cellular uptake. Furthermore, the acidic tumor microenvironment attracts BRM270 NPs enhancing targeted therapy while leaving normal cells less affected. The comparative cytotoxicity analysis using MTT assay among the three treatment groups, such as free BRM270, BRM270 NPs, and doxorubicin demonstrated that BRM270 NPs induced greater cytotoxicity against HepG2 cells with an effective drug concentration of 12 μg/ml. From FACS analysis, we observed an apoptotic cell death of 44.4% at BRM270 NPs treated cells while only 12.5% found in the free BRM270 treated cells. Further, the comparative relative expression profiling of the candidate genes were showed significant (p < 0.05) down-regulation of IL6, BCL2, p53, and MMP9 in the BRM270 NPs treated cells, compared to the free BRM270 and doxorubicin. Indeed, the genes, CASPASE 9 and BAX have shown significant (p < 0.05) upregulation in cells treated with BRM270 NPs as compared to counter treatment groups. The investigation of the signal pathways and protein-protein network associations were also carried out to elucidate the functional insights underlying anti-cancer potential of BRM270 NPs in HepG2 cells. Taken together, our findings demonstrated that these uniquely engineered BRM270 NPs effectively enter into the cancer cells due to its acidic microenvironment thereby inducing apoptosis and regulate the cell-proliferation in-vitro at extremely low dosages.

Switchable up-conversion luminescence bioimaging and targeted photothermal ablation in one core–shell-structured nanohybrid by alternating near-infrared light

Upon NIR irradiation, a GdOF:Yb/Er@(GNRs@BSA)-FA nanohybrid was expected to be a potential multifunctional imaging tracer and photothermal ablation agent switched controllably for cancer theranostics.

Ultra-small bimetallic iron–palladium (FePd) nanoparticle loaded macrophages for targeted tumor photothermal therapy in NIR-II biowindows and magnetic resonance imaging

Nanoparticles working in the NIR-II biowindows possess larger maximum permissible exposure (MPE) and desirable penetration depth to the laser. However, most NIR-II responsive nanomaterials lack tumor targeting and Magnetic Resonance Imaging (MRI) ability. This greatly limits their applications. This study reported ultra-small bimetallic iron–palladium (FePd) nanoparticle loaded macrophages for targeted tumor photothermal therapy in NIR-II biowindows and magnetic resonance imaging. The crystal phase, morphology, absorption spectrum and photothermal performance of the synthesized samples were systematically characterized. The effects of photothermal therapy and nuclear magnetic imaging (MRI) were studied both in vitro and in vivo. Since FePd nanoparticles have both iron and palladium elements, it had a good MRI imaging capability and high photothermal conversion efficiency (36.7%). After binding to macrophages, FePd nanoparticles@macrophages (FePd@M) showed a good tumor targeting ability and were used for targeting NIR-II photothermal therapy and MRI imaging of tumors. The results of photothermal treatment showed that the tumor volume decreased by 90% compared to the control group, and no significant organ toxicity was observed. The results of MRI imaging showed that the FePd@M has the best imaging effect. The nanoparticles with the excellent NIR-II PTT ability and MRI effect have overcome the problem of tumor targeting and avoid the rapid removal of ultra-small nanoparticles. The FePd@M delivery system provides new ideas for material construction in the NIR-II region and has great clinical application potential.

Nanoparticles working in the NIR-II biowindows possess larger maximum permissible exposure (MPE) and desirable penetration depth to the laser.

The effect of low- and high-penetration light on localized cancer therapy

The design of a delivery system allowing targeted and controlled drug release has been considered one of the main strategies used to provide individualized cancer therapy, to improve survival statistics, and to enhance quality-of-life. External stimuli including low- and high-penetration light have been shown to have the ability to turn drug delivery on and off in a non-invasive remotely-controlled fashion. The success of this approach has been closely related to the development of a variety of drug delivery systems - from photosensitive liposomes to gold nanocages - and relies on multiple mechanisms of drug release activation. In this review, we make reference to the two extremes of the light spectrum and their potential as triggers for the delivery of antitumor drugs, along with the most recent achievements in preclinical trials and the challenges to an efficient translation of this technology to the clinical setting.

On-Demand Versatile Prodrug Nanomicelle for Tumor-Specific Bioimaging and Photothermal-Chemo Synergistic Cancer Therapy

Photothermal therapy is a promising approach for antitumor application although regrettably restricted by available photothermal agents. Physical entrapment of organic near-infrared dyes into nanosystems was extensively studied to reverse the dilemma. However, problems still remained, such as drug bursting and leakage. We developed here an amphiphilic prodrug conjugate by chemically modifying indocyanine green derivative (ICG-COOH) and paclitaxel (PTX) to hyaluronic acid (HA) backbone for integration of photothermal-chemotherapy and specific tumor imaging. The prepared ICG-HA-PTX conjugates could self-assemble into nanomicelles to improve the stability and reduce systemic toxicity of the therapeutic agents. The high local concentration of ICG-COOH in nanomicelles resulted in fluorescence self-quenching, leading to no fluorescence signal being detected in circulation. When the nanomicelles reached the tumor site via electron paramagnetic resonance effect and HA-mediated active targeting, the overexpressed esterase in tumor cells ruptured the ester linkage between drugs and HA, achieving tumor-targeted therapy and specific imaging. A series of in vitro and in vivo experiments demonstrated that the easily prepared ICG- HA-PTX nanomicelles with high stability, smart release behavio r, and excellent tumor targeting ability showed formidable synergy in tumor inhibition, which provided new thoughts in developing an organic near-infrared-dye-based multifunctional delivery system for tumor theranostics.

Biosynthesis of flower-shaped Au nanoclusters with EGCG and their application for drug delivery

Background

In the last decade, the biosynthesis of metal nanoparticles using organisms have received more and more considerations. However, the complex composition of organisms adds up to a great barrier for the characterization of biomolecules involved in the synthesis process and their biological mechanisms.

Results

In this research, we biosynthesized a kind of flower-shaped Au nanoclusters (Au NCs) using one definite component—epigallocatechin gallate (EGCG), which was the main biomolecules of green tea polyphenols. Possessing good stability for 6 weeks and a size of 50 nm, the Au NCs might be a successful candidate for drug delivery. Hence, both methotrexate (MTX) and doxorubicin (DOX) were conjugated to the Au NCs through a bridge of cysteine (Cys). The introduction of MTX provided good targeting property for the Au NCs, and the conjugation of DOX provided good synergistic effect. Then, a novel kind of dual-drug loaded, tumor-targeted and highly efficient drug delivery system (Au-Cys-MTX/DOX NCs) for combination therapy was successfully prepared. The TEM of HeLa cells incubated with Au-Cys-MTX/DOX NCs indicated that the Au-Cys-MTX/DOX NCs could indeed enter and kill cancer cells. The Au-Cys-MTX/DOX NCs also possessed good targeting effect to the FA-receptors-overpressed cancer cells both in vitro and in vivo. Importantly, the Au-Cys-MTX/DOX NCs resulted in an excellent anticancer activity in vivo with negligible side effects.

Conclusions

These results suggest that the biosynthesized Au-Cys-MTX/DOX NCs could be a potential carrier with highly efficient anticancer properties for tumor-targeted drug delivery.

Electronic supplementary material

The online version of this article (10.1186/s12951-018-0417-3) contains supplementary material, which is available to authorized users.

Polytyrosine nanoparticles enable ultra-high loading of doxorubicin and rapid enzyme-responsive drug release

Despite the great significance of clinically viable nanovehicles, very few of them exhibit stability and high anticancer drug loading with fast intracellular drug release. Herein, we report that polytyrosine nanoparticles (PTNs) self-assembled from poly(ethylene glycol)-b-poly(l-tyrosine) block copolymer enable the ultra-high loading and rapid enzyme-responsive release of doxorubicin (DOX). Notably, PTNs achieve a remarkably high DOX loading of 63.1 wt% likely due to the existence of strong π-π stacking between polytyrosine and DOX, as shown by UV-vis analysis. Additionally, PTNs present a high docetaxel loading of 17.5 wt%. Furthermore, PTNs exhibit good colloidal stability in 10% FBS, but are quickly de-stabilized by proteinase K. Interestingly, ca. 90% of DOX is released under 6 U mL-1 proteinase K in 24 h or in RAW 264.7 cells in 8 h. The DOX-loaded PTNs display efficient delivery and release of DOX in both RAW 264.7 cells and HCT-116 human colorectal cancer cells, achieving a better in vitro antiproliferative effect than the clinically used liposomal DOX formulation. Thus, these polytyrosine nanoparticles appear to be a potentially viable platform for the controlled delivery of anthraquinone anticancer agents.

Folate receptor-targeted liposomal nanocomplex for effective synergistic photothermal-chemotherapy of breast cancer in vivo

An effective nanoparticle-based drug delivery platform holds great promise for non-invasive cancer therapy. This study explores the breast tumor regression in vivo by synergistic photothermal-chemotherapy based on liposomal nanocomplex (folic acid-gold nanorods-anticancer drug-liposome). The proposed liposomal nanocomplex can enhance the tumor targeting by functionalizing folic acid (FA) molecules on the surface of liposome that encapsulates both gold nanorods (AuNRs) and the doxorubicin (DOX) to combine the photothermal therapy and the chemotherapy, respectively. Herein, 7-nm gold nanorods were fabricated and co-encapsulated with DOX into nanoliposomes functionalized with FA, with an average diameter of 154 nm, for active targeting to the cancer cells. The experimental results showed that the FA targeting liposomes had better cellular uptake than the non-targeting liposomes (AuNRs-DOX-LPs). Especially, upon 5 min exposure to near infrared (NIR) irradiation (808 nm) triggered DOX release could be achieved to 46.38% in 60 min at pH 5.5. In addition, in vitro cell proliferation assays indicated that, with synergistic photothermal-chemotherapy, the targeting liposomes could significantly enhance the toxicity towards the cancer cells with the IC₅₀ value of 1.90 ± 0.12 μg mL^-1. Furthermore, in vivo experiments on the breast tumor-bearing mice showed that the targeting liposomes could effectively inhibit the growth of the tumors using the combined strategy.

In Situ Growth of CuS/SiO2-Based Multifunctional Nanotherapeutic Agents for Combined Photodynamic/Photothermal Cancer Therapy

A scalable and low-cost strategy is developed to fabricate a novel CuS/SiO₂-based nanotherapeutic agent for dual-model imaging-guided photothermal/photodynamic combined therapy. In this design, mesoporous silica nanoparticles (MSNs) with CuS bundled in the channel are obtained in aqueous solution via in situ growth route for the first time. Furthermore, to achieve a more efficient therapy, photosensitizer (complex Ir-2) and bovine serum albumin are sequentially assembled via layer-by-layer method. The as-prepared complex Ir-2 presents a remarkably high ¹O₂ generation (Φ_Δ = 1.3) under light illumination to offer effective photodynamic cell killing, and MSN/CuS exhibits high photothermal conversion efficiency (η = 31.7%) under illumination by 808 nm light to offer hyperthermia tumor ablation. In vitro and in vivo analyses show that the as-obtained nanotherapeutic agents exhibit excellent performance in tumor therapy even under irradiation with low power because of the high yield of ¹O₂ combined with the high photothermal conversion efficiency. Additionally, the nanotherapeutic agents are readily visualized in vivo via near-infrared fluorescence and thermal imaging. More importantly, based on the strategy of in situ growth and layer-by-layer assembly developed in this study, the development of other "all-in-one" multifunctional theranostic platform with high efficiency can be predictable.

Near-Infrared-Responsive Cancer Photothermal and Photodynamic Therapy Using Gold Nanoparticles

Rapid growth of nanotechnology is one of the most quickly emerging tendencies in cancer therapy. Gold nanoparticles roused a distinctive interest in the field, due to their incomparable light-to-thermal energy conversion efficiency, and their ability to load and deliver a variety of anticancer drugs. Therefore, simultaneous photothermal (PTT) and photodynamic (PDT) cancer therapy is available by the role of the thermal agent of the gold nanoparticle itself and the drug delivery carrier for photosensitizer (PS) transport. In this review, the physical, chemical, and biological properties of gold nanoparticle, which can promote PTT and PDT efficiency, are briefly demonstrated, and we highlight recent progression in the development of PS-containing gold nanocomposites for effective cancer therapy.

Surface-Modified Macrophages Facilitate Tracking of Breast Cancer-Immune Interactions

The immune system has been found to play key roles in cancer development and progression. Macrophages are typically considered to be pro-inflammatory cells but can also facilitate pro-oncogenic activities via associations with tumors and metastases. The study of macrophages and their interactions within the context of cancer microenvironments is stymied by the lack of a system to track them. We present a cell-based strategy for studying cancer-immune cell interactions by chemically modifying the surfaces of macrophages with fluorophores. Two widely used methods are employed, affecting cell surface proteins and glycans via NHS-ester and Staudinger ligation reactions, respectively. We show that these modifications do not interfere with macrophage responses to chemoattractants and that interactions with cancer cells can be readily monitored. This work describes the development of macrophage-based imaging agents for tumor detection and assessment of interactions between immune cells and cancers.

Photoacoustic Imaging-Guided Photothermal Therapy with Tumor-Targeting HA-FeOOH@PPy Nanorods

Cancer theragnosis agents with both cancer diagnosis and therapy abilities would be the next generation of cancer treatment. Recently, nanomaterials with strong absorption in near-infrared (NIR) region have been explored as promising cancer theragnosis agents for bio-imaging and photothermal therapy (PTT). Herein, we reported the synthesis and application of a novel multifunctional theranostic nanoagent based on hyaluronan (HA)-coated FeOOH@polypyrrole (FeOOH@PPy) nanorods (HA-FeOOH@PPy NRs) for photoacoustic imaging (PAI)-guided PTT. The nanoparticles were intentionally designed with rod-like shape and conjugated with tumor-targeting ligands to enhance the accumulation and achieve the entire tumor distribution of nanoparticles. The prepared HA-FeOOH@PPy NRs showed excellent biocompatible and physiological stabilities in different media. Importantly, HA-FeOOH@PPy NRs exhibited strong NIR absorbance, remarkable photothermal conversion capability, and conversion stability. Furthermore, HA-FeOOH@PPy NRs could act as strong contrast agents to enhance PAI, conducting accurate locating of cancerous tissue, as well as precise guidance for PTT. The in vitro and in vivo photothermal anticancer activity results of the designed nanoparticles evidenced their promising potential in cancer treatment. The tumor-bearing mice completely recovered after 17 days of PTT treatment without obvious side effects. Thus, our work highlights the great potential of using HA-FeOOH@PPy NRs as a theranostic nanoplatform for cancer imaging-guided therapy.

Magnetic Mesoporous Calcium Sillicate/Chitosan Porous Scaffolds for Enhanced Bone Regeneration and Photothermal-Chemotherapy of Osteosarcoma

The development of multifunctional biomaterials to repair bone defects after neoplasm removal and inhibit tumor recurrence remained huge clinical challenges. Here, we demonstrate a kind of innovative and multifunctional magnetic mesoporous calcium sillicate/chitosan (MCSC) porous scaffolds, made of M-type ferrite particles (SrFe₁₂O₁₉), mesoporous calcium silicate (CaSiO₃) and chitosan (CS), which exert robust anti-tumor and bone regeneration properties. The mesopores in the CaSiO₃ microspheres contributed to the drug delivery property, and the SrFe₁₂O₁₉ particles improved photothermal therapy (PTT) conversion efficacy. With the irradiation of NIR laser, doxorubicin (DOX) was rapidly released from the MCSC/DOX scaffolds. In vitro and in vivo tests demonstrated that the MCSC scaffolds possessed the excellent anti-tumor efficacy via the synergetic effect of DOX drug release and hyperthermia ablation. Moreover, BMP-2/Smad/Runx2 pathway was involved in the MCSC scaffolds promoted proliferation and osteogenic differentiation of human bone marrow stromal cells (hBMSCs). Taken together, the MCSC scaffolds have the ability to promote osteogenesis and enhance synergetic photothermal-chemotherapy against osteosarcoma, indicating MCSC scaffolds may have great application potential for bone tumor-related defects.

Black-Phosphorus-Incorporated Hydrogel as a Sprayable and Biodegradable Photothermal Platform for Postsurgical Treatment of Cancer

Photothermal therapy (PTT) is a fledgling therapeutic strategy for cancer treatment with minimal invasiveness but clinical adoption has been stifled by concerns such as insufficient biodegradability of the PTT agents and lack of an efficient delivery system. Here, black phosphorus (BP) nanosheets are incorporated with a thermosensitive hydrogel [poly(d,l-lactide)-poly(ethylene glycol)-poly(d,l-lactide) (PDLLA-PEG-PDLLA: PLEL)] to produce a new PTT system for postoperative treatment of cancer. The BP@PLEL hydrogel exhibits excellent near infrared (NIR) photothermal performance and a rapid NIR-induced sol-gel transition as well as good biodegradability and biocompatibility in vitro and in vivo. Based on these merits, an in vivo PTT postoperative treatment strategy is established. Under NIR irradiation, the sprayed BP@PLEL hydrogel enables rapid gelation forming a gelled membrane on wounds and offers high PTT efficacy to eliminate residual tumor tissues after tumor removal surgery. Furthermore, the good photothermal antibacterial performance prevents infection and this efficient and biodegradable PTT system is very promising in postoperative treatment of cancer.

Generation of Well-Defined Micro/Nanoparticles via Advanced Manufacturing Techniques for Therapeutic Delivery

Micro/nanoparticles have great potentials in biomedical applications, especially for drug delivery. Existing studies identified that major micro/nanoparticle features including size, shape, surface property and component materials play vital roles in their in vitro and in vivo applications. However, a demanding challenge is that most conventional particle synthesis techniques such as emulsion can only generate micro/nanoparticles with a very limited number of shapes (i.e., spherical or rod shapes) and have very loose control in terms of particle sizes. We reviewed the advanced manufacturing techniques for producing micro/nanoparticles with precisely defined characteristics, emphasizing the use of these well-controlled micro/nanoparticles for drug delivery applications. Additionally, to illustrate the vital roles of particle features in therapeutic delivery, we also discussed how the above-mentioned micro/nanoparticle features impact in vitro and in vivo applications. Through this review, we highlighted the unique opportunities in generating controllable particles via advanced manufacturing techniques and the great potential of using these micro/nanoparticles for therapeutic delivery.

Radiotherapy-Sensitized Tumor Photothermal Ablation Using γ-Polyglutamic Acid Nanogels Loaded with Polypyrrole

Development of versatile nanoscale platforms for cancer diagnosis and therapy is of great importance for applications in translational medicine. In this work, we present the use of γ-polyglutamic acid (γ-PGA) nanogels (NGs) to load polypyrrole (PPy) for thermal/photoacoustic (PA) imaging and radiotherapy (RT)-sensitized tumor photothermal therapy (PTT). First, a double emulsion approach was used to prepare the cystamine dihydrochloride (Cys)-cross-linked γ-PGA NGs. Next, the cross-linked NGs served as a reactor to be filled with pyrrole monomers that were subjected to in situ oxidation polymerization in the existence of Fe(III) ions. The formed uniform PPy-loaded NGs having an average diameter of 38.9 ± 8.6 nm exhibited good water-dispersibility and colloid stability. The prominent near-infrared (NIR) absorbance feature due to the loaded PPy endowed the NGs with contrast enhancement in PA imaging. The hybrid NGs possessed excellent photothermal conversion efficiency (64.7%) and stability against laser irradiation, and could be adopted for PA imaging and PTT of cancerous cells and tumor xenografts. Importantly, we also explored the cooperative PTT and X-ray radiation-mediated RT for enhanced tumor therapy. We show that PTT of tumors can be more significantly sensitized by RT using the sequence of laser irradiation followed by X-ray radiation as compared to using the reverse sequence. Our study suggests a promising theranostic platform of hybrid NGs that may be potentially utilized for PA imaging and combination therapy of different types of tumors.

Antibody-Conjugated Silica-Modified Gold Nanorods for the Diagnosis and Photo-Thermal Therapy of Cryptococcus neoformans: an Experiment In Vitro

BACKGROUND

Cryptococcus neoformans is an encapsulated yeast. There is still little quick and effective solution for the diagnosis or treatment of C. neoformans infection at an early stage in clinical. Antibody-conjugated silica-modified gold nanorods (GNR-SiO₂-Ab) can conjugate C. neoformans selectively. It may provide a possibility for treatment of cryptococcosis safely and effectively.

METHODS

Gold nanorods (GNRs) were synthesized according to the seed-mediated template-assisted protocol. Anti-C. neoformans antibody was covalently anchored on the surface of GNRs with silane coupling agent. In vitro computer tomography imaging was performed to explore the diagnostic effect of the GNR-SiO₂-Ab. The viability of cells was evaluated to confirm the photo-thermal therapy effect of GNR-SiO₂-Ab combined with near-infrared (NIR) laser light.

RESULTS

GNR-SiO₂-Ab has a potential application as a positive X-ray/CT imaging contrast agent. An antibody can induce a much greater aggregation of GNRs by binding to the surface of C. neoformans cells resulting in a much higher attenuation values than ever. After irradiation, C. neoformans cells suffered photo-thermal damages and the normal structure of cells were destroyed. The viability of cells reduced significantly compared to the untreated cells.

CONCLUSIONS

Our work confirmed that antibody-conjugated silica-modified gold nanorods could enhance X-ray attenuation of C. neoformans cells in CT images. And immune GNRs, which were mediated by antibodies, could increase the effects of NIR-induced photo-thermal therapy in C. neoformans cells.

Laser assisted anticancer activity of benzimidazole based metal organic nanoparticles

Recent studies showed that the photothermal therapy can be effectively used for the targeted cancerous cells destruction. Hence, in the present study, benzimidazole based metal organic complex nanoparticles, dichloro cobalt(II) bis-benzimidazole (Co-BMZ) and dichloro copper(II) bis-benzimidazole (Cu-BMZ), were synthesized by reprecipitation method and their anti-cancer activity by means of photothermal effect has been studied. Transmission electron microscopy analysis shows that the particle size of Cu-BMZ is ∼100 nm and Co-BMZ is in the range between 100 and 400 nm. Zeta potential analysis ensures the stability of the synthesized nanoparticles. It is found that the nonlinear absorption of the nanoparticles increases with increase in laser power intensity. Phototoxicity of human lung cancer (A549) and the normal mouse embryonic fibroblast (NIH-3T3) cells was studied using a 650 nm laser. Even though both the cell lines were affected by laser irradiation, A549 cells show higher cell destruction and lower IC₅₀ values than the normal cells. Docking studies were used to analyse the interaction site and the results showed that the Cu-BMZ molecules have higher dock score than the Co-BMZ molecules. The obtained results indicate that Cu-BMZ samples have lesser particle size, higher nonlinear absorption and higher interaction energy than the Co-BMZ samples.

DNA Damage and Apoptosis Induction in Cancer Cells by Chemically Engineered Thiolated Riboflavin Gold Nanoassembly

Herein we have engineered a smart nuclear targeting thiol-modified riboflavin-gold nano assembly, RfS@AuNPs, which accumulates selectively in the nucleus without any nuclear-targeting peptides (NLS/RGD) and shows photophysically in vitro DNA intercalation. A theoretical model using Molecular Dynamics has been developed to probe the mechanism of formation and stability as well as dynamics of the RfS@AuNPs in aqueous solution and within the DNA microenvironment. The RfS@AuNPs facilitate the binucleated cell formation that is reflected in the significant increase of DNA damage marker, γ-H2AX as well as the arrest of most of the HeLa cells at the pre-G1 phase indicating cell death. Moreover, a significant upregulation of apoptotic markers confirms that the cell death occurs through the apoptotic pathway. Analyses of the microarray gene expression of RfS@AuNPs treated HeLa cells show significant alterations in vital biological processes necessary for cell survival. Taken together, our study reports a unique nuclear targeting mechanism through targeting the riboflavin receptors, which are upregulated in cancer cells and induce apoptosis in the targeted cells.

Tumor-tropic endothelial colony forming cells (ECFCs) loaded with near-infrared sensitive Au nanoparticles: A "cellular stove" approach to the photoablation of melanoma

In the photothermal treatments (PTs) of tumor, the localization of a high number of near-infrared (NIR) absorbing gold nanoparticles in the tumor mass is still a challenging issue. Here, we propose a promising strategy to deliver therapeutic chitosan-coated gold nanoparticles to tumor cells as hidden cargo of Endothelial Colony Forming Cells (ECFCs) endowed with an innate tumor-tropism. Remarkably, ECFC gold enrichement doesn't affect cell viability and preserves the endothelial lineage characteristics such as capillary morphogenesis and cell migration. We demonstrate that heavily Au-doped ECFCs are able to efficiently warm up the tumor environment, and kill the cancer cells via hyperthermic heating both in vitro as well as in vivo. Thus, we show an excellent thermotransductive property of gold enriched ECFCs and their capability to kill melanoma cells at moderate NIR light intensities.

Biomimetic albumin-modified gold nanorods for photothermo-chemotherapy and macrophage polarization modulation

Nanotechnology-based photothermal therapy has attracted great attention in the past decade. Nevertheless, photothermal therapy has some inherent drawbacks, such as the uneven heat production and limited laser penetration, often leading to insufficient treatment outcomes. Here, we developed a combination strategy to improve cancer therapy. The biomimetic albumin-modified gold nanorods (AuNRs) were prepared with incorporation of paclitaxel (PTX). This therapeutic system was characterized by several features. First, the albumin modification enhanced the biocompatibility and colloidal stability. Second, the surface-coated albumin promoted cellular uptake via the albumin-binding protein pathway. Third, PTX was incorporated via hydrophobic interaction between PTX and the albumin lipophilic domain. Fourth, the system can be used for combined photothermo-chemotherapy for yielding synergistic effects. The antitumor activity of the system was evaluated both in vitro and in vivo using the HCT116 colon cancer cell and tumor model. The combination therapy was found with an enhanced treatment efficiency and no obvious side effect. Most importantly, the thermal effect was also discovered with the ability to modulate the tumor microenvironments and suppress the macrophages polarization towards the M2 pro-tumor phenotype. It could be a mechanism for photothermal immunotherapy. The combination strategy and the system provide a potential method for cancer therapy.

Facile preparation of versatile gadolinium-chelated protein nanocomposite for T1 magnetic resonance imaging-guided photodynamic and photothermal synergetic therapy

Imaging-guided photodynamic/photothermal (PDT/PTT) synergetic therapy is important in more precise and efficient cancer treatment.

Plasmonic CuS nanodisk assembly based composite nanocapsules for NIR-laser-driven synergistic chemo-photothermal cancer therapy

The NIR-laser-driven plasmonic photothermal and sustained drug release behavior of CuS–PTX/SiO₂ nanocapsules show great synergistic chemo-photothermal therapeutic effects on cancer cells in vitro and in vivo.

Platelet-Facilitated Photothermal Therapy of Head and Neck Squamous Cell Carcinoma

Here, we present a platelet-facilitated photothermal tumor therapy (PLT-PTT) strategy, in which PLTs act as carriers for targeted delivery of photothermal agents to tumor tissues and enhance the PTT effect. Gold nanorods (AuNRs) were first loaded into PLTs by electroporation and the resulting AuNR-loaded PLTs (PLT-AuNRs) inherited long blood circulation and cancer targeting characteristics from PLTs and good photothermal property from AuNRs. Using a gene-knockout mouse model, we demonstrate that the administration of PLT-AuNRs and localizing laser irradiation could effectively inhibit the growth of head and neck squamous cell carcinoma (HNSCC). In addition, we found that the PTT treatment augmented PLT-AuNRs targeting to the tumor sites and in turn, improved the PTT effects in a feedback manner, demonstrating the unique self-reinforcing characteristic of PLT-PTT in cancer therapy.