Near-infrared light triggers release of Paclitaxel from biodegradable microspheres: photothermal effect and enhanced antitumor activity

Antibacterial and Biofilm Removal Strategies Based on Micro/Nanomotors in the Biomedical Field

Bacterial infection, which can trigger varieties of diseases and tens of thousands of deaths each year, poses serious threats to human health. Particularly, the new dilemma caused by biofilms is gradually becoming a severe and tough problem in the biomedical field. Thus, the strategies to address these problems are considered an urgent task at present. Micro/nanomotors (MNMs), also named micro/nanoscale robots, are mostly driven by chemical energy or external field, exhibiting strong diffusion and self-propulsion in the liquid media, which has the potential for antibacterial applications. In particular, when MNMs are assembled in swarms, they become robust and efficient for biofilm removal. However, there is a lack of comprehensive review discussing the progress in this aspect. Bearing it in mind and based on our own research experience in this regard, the studies on MNMs driven by different mechanisms orchestrated for antibacterial activity and biofilm removal are timely and concisely summarized and discussed in this work, aiming to show the advantages of MNMs brought to this field. In addition, an outlook was proposed, hoping to provide the fundamental guidance for future development in this area.

Aptamer and Peptide-Engineered Polydopamine Nanospheres for Target Delivery and Tumor Perfusion in Synergistic Chemo-Phototherapy of Pancreatic Cancer

Pancreatic cancer (PC) is the fourth leading cause of cancer death, and the 5 year survival rate is only 4%. Chemotherapy is the treatment option for the majority of PC patients diagnosed at an advanced stage, whereas the desmoplastic stroma of PC could block the perfusion of chemotherapeutic agents to tumor tissues and contribute generally to chemoresistance. Therefore, the clinical status of PC calls for an urgent exploration in the effective treatment strategy. Chemo-phototherapy is an emerging modality against malignant tumors, but owing to the low targeting ability of theranostic agents or unspecific accumulation in the tumor region, majority of chemo-phototherapy techniques have disappointing therapeutic efficiencies. Herein, we have explored CD71-specific targeting aptamers and paclitaxel (PTX)-modified polydopamine (PDA) nanospheres with the conjugation of peptidomimetic AV3 (termed Apt-PDA@PTX/AV3 bioconjugates) to specifically target and combat PC in vivo by synergistic chemo-phototherapy. After the delivery of nanotheranostic agents to the tumor microenvironment (TME) or subsequent endocytic uptake by PC cells, a simultaneous release of AV3 and PTX from Apt-PDA@PTX/AV3 bioconjugates via near-infrared (NIR) irradiation can decrease desmoplastic stroma to enhance tumor perfusion and tumor-killing effects. Meanwhile, PDA cores utilize NIR laser to create unendurable hyperthermia within TME to "cook" tumors. Taken together, the current study finally suggests that our Apt-PDA@PTX/AV3 bioconjugates could act as a novel therapeutic approach by synergistic chemo-phototherapy for the programmable inhibition of PC.

Coiled-coil peptide-based assembly of a plasmonic core-satellite polymer-metal nanocomposite as an efficient photothermal agent for drug delivery applications

Polymer-metal nanocomposites have widespread applications in biomedical fields such as imaging, catalysis, and drug delivery. These particles are characterized by combined organic and inorganic properties. Specifically, photothermal nanocomposites incorporating polymeric and plasmonic nanoparticles (NPs) have been designed for both triggered drug release and as imaging agents. However, the usual design of nanocomposites confers characteristic issues, among which are the decrease of optical properties and resulting low photothermal efficiency, as well as interactions with loaded drugs. Herein, we report the design of a core-satellite polymer-metal nanocomposite assembled by coiled-coil peptides and its superior photothermal efficiency compared to electrostatic-driven nanocomposites which is the standard design. We also found that the orientation of gold nanorods on the surface of polymeric NPs is of importance in the final photothermal efficiency and could be exploited for various applications. Our findings provide an alternative to current wrapping and electrostatic assembly of nanocomposites with the help of coiled-coil peptides and an improvement of the control over core-satellite assemblies with plasmonic NPs. It paves the way to highly versatile assemblies due to the nature of coiled-coil peptides to be easily modified and sensitive to pH or temperature.

Tumor cell membrane-camouflaged responsive nanoparticles enable MRI-guided immuno-chemodynamic therapy of orthotopic osteosarcoma

Osteosarcoma is a refractory bone disease in young people that needs the updating and development of effective treatment. Although nanotechnology is widely applied in cancer therapy, poor targeting and inadequate efficiency hinder its development. In this study, we prepared alendronate (ALD)/K7M2 cell membranes-coated hollow manganese dioxide (HMnO₂) nanoparticles as a nanocarrier to load Ginsenoside Rh2 (Rh2) for Magnetic Resonance imaging (MRI)-guided immuno-chemodynamic combination osteosarcoma therapy. Subsequently, the ALD and K7M2 cell membranes were successively modified on the surface of HMnO₂ and loaded with Rh2. The tumor microenvironment (TME)-activated Rh2@HMnO₂-AM nanoparticles have good bone tumor-targeting and tumor-homing capabilities, excellent GSH-sensitive drug release profile and MRI capability, and attractive immuno-chemodynamic combined therapeutic efficiency. The Rh2@HMnO₂-AM nanoparticles can effectively trigger immunogenic cell death (ICD), activate CD4⁺/CD8⁺ T cells in vivo, and upregulate BAX, BCL-2 and Caspase-3 in cellular level. Further results revealed that Rh2@HMnO₂-AM enhanced the secretion of IL-6, IFN-γ and TNF-α in serum and inhibited the generation of FOXP3⁺ T cells (Tregs) in tumors. Moreover, the Rh2@HMnO₂-AM treatment significant restricted tumor growth in-situ tumor-bearing mice. Therefore, Rh2@HMnO₂-AM may serve as an effective and bio-friendly nanoparticle platform combined with immunotherapy and chemodynamic therapy to provide a novel approach to osteosarcoma therapy.

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Ginsenoside Rh2 was loaded in Hollow MnO₂ NPs for enhancing its bioavailability.

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The orthotopic tumor model exhibits a convincing therapeutic effect of nanosystems.

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Alendronate/cell membranes enhance osteosarcoma targeting and tumor-homing ability.

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Tumor microenvironment-induced NPs degradation can release immune stimulant and Mn²⁺.

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The NPs had excellent immuno-chemodynamic combination osteosarcoma therapy effect.

Design Principles Governing the Development of Theranostic Anticancer Agents and Their Nanoformulations with Photoacoustic Properties

The unmet need to develop novel approaches for cancer diagnosis and treatment has led to the evolution of theranostic agents, which usually include, in addition to the anticancer drug, an imaging agent based mostly on fluorescent agents. Over the past few years, a non-invasive photoacoustic imaging modality has been effectively integrated into theranostic agents. Herein, we shed light on the design principles governing the development of theranostic agents with photoacoustic properties, which can be formulated into nanocarriers to enhance their potency. Specifically, we provide an extensive analysis of their individual constituents including the imaging dyes, drugs, linkers, targeting moieties, and their formulation into nanocarriers. Along these lines, we present numerous relevant paradigms. Finally, we discuss the clinical relevance of the specific strategy, as also the limitations and future perspectives, and through this review, we envisage paving the way for the development of theranostic agents endowed with photoacoustic properties as effective anticancer medicines.

Near infrared light fluorescence imaging-guided biomimetic nanoparticles of extracellular vesicles deliver indocyanine green and paclitaxel for hyperthermia combined with chemotherapy against glioma

Background

We investigated the therapeutic effect of targeting extracellular vesicles (EVs) loaded with indocyanine green (ICG) and paclitaxel (PTX) on glioma.

Methods

Raw264.7 cells were harvested to extract EVs for the preparation of ICG/PTX@RGE-EV by electroporation and click chemistry. We evaluated the success of modifying Neuropilin-1 targeting peptide (RGE) on the EV membrane of ICG/PTX@RGE-EV using super-resolution fluorescence microscopy and flow cytometry. Spectrophotometry and high performance liquid chromatography (HPLC) were implemented for qualitative and quantitative analysis of the ICG and PTX loaded in EVs. Photothermal properties of the vesicles were evaluated by exposing to 808-nm laser light. Western blot analysis, cell counting kit 8 (CCK-8), Calcein Acetoxymethyl Ester/propidium iodide (Calcein-AM/PI) staining, and flow cytometry were utilized for assessing effects of vesicle treatment on cellular behaviors. A nude mouse model bearing glioma was established to test the targeting ability and anti-tumor action of ICG/PTX@RGE-EV in vivo.

Results

Under exposure to 808-nm laser light, ICG/PTX@RGE-EV showed good photothermal properties and promotion of PTX release from EVs. ICG/PTX@RGE-EV effectively targeted U251 cells, with activation of the Caspase-3 pathway and elevated apoptosis in U251 cells through chemotherapy combined with hyperthermia. The anti-tumor function of ICG/PTX@RGE-EV was confirmed in the glioma mice via increased accumulation of PTX in the ICG/PTX@RGE-EV group and an increased median survival of 48 days in the ICG/PTX@RGE-EV group as compared to 25 days in the PBS group.

Conclusion

ICG/PTX@RGE-EV might actively target glioma to repress tumor growth by accelerating glioma cell apoptosis through combined chemotherapy-hyperthermia.

Graphic Abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s12951-021-00907-3.

Nanostructured Surface Finishing and Coatings: Functional Properties and Applications

This review presents current literature on different nanocomposite coatings and surface finishing for textiles, and in particular this study has focused on smart materials, drug-delivery systems, industrial, antifouling and nano/ultrafiltration membrane coatings. Each of these nanostructured coatings shows interesting properties for different fields of application. In this review, particular attention is paid to the synthesis and the consequent physico-chemical characteristics of each coating and, therefore, to the different parameters that influence the substrate deposition process. Several techniques used in the characterization of these surface finishing coatings were also described. In this review the sol-gel method for preparing stimuli-responsive coatings as smart sensor materials is described; polymers and nanoparticles sensitive to pH, temperature, phase, light and biomolecules are also treated; nanomaterials based on phosphorus, borates, hydroxy carbonates and silicones are used and described as flame-retardant coatings; organic/inorganic hybrid sol-gel coatings for industrial applications are illustrated; carbon nanotubes, metallic oxides and polymers are employed for nano/ultrafiltration membranes and antifouling coatings. Research institutes and industries have collaborated in the advancement of nanotechnology by optimizing conversion processes of conventional materials into coatings with new functionalities for intelligent applications.

Evaluation of novel paclitaxel-loaded NO-donating polymeric micelles for an improved therapy for gastroenteric tumor

A NO-releasing polymer (mPEG-PLA-NO) is developed as a micellar nanoparticle delivery system for the carrier of antitumor drug paclitaxel.

Visible-to-NIR-Light Activated Release: From Small Molecules to Nanomaterials

Photoactivatable (alternatively, photoremovable, photoreleasable, or photocleavable) protecting groups (PPGs), also known as caged or photocaged compounds, are used to enable non-invasive spatiotemporal photochemical control over the release of species of interest. Recent years have seen the development of PPGs activatable by biologically and chemically benign visible and near-infrared (NIR) light. These long-wavelength-absorbing moieties expand the applicability of this powerful method and its accessibility to non-specialist users. This review comprehensively covers organic and transition metal-containing photoactivatable compounds (complexes) that absorb in the visible- and NIR-range to release various leaving groups and gasotransmitters (carbon monoxide, nitric oxide, and hydrogen sulfide). The text also covers visible- and NIR-light-induced photosensitized release using molecular sensitizers, quantum dots, and upconversion and second-harmonic nanoparticles, as well as release via photodynamic (photooxygenation by singlet oxygen) and photothermal effects. Release from photoactivatable polymers, micelles, vesicles, and photoswitches, along with the related emerging field of photopharmacology, is discussed at the end of the review.

Self-Propelled Active Photothermal Nanoswimmer for Deep-Layered Elimination of Biofilm In Vivo

Increasing penetration of antibacterial agents into biofilm is a promising strategy for improvement of therapeutic effect and slowdown of the progression of antibiotic resistance. Herein, we design a near-infrared (NIR) light-driven nanoswimmer (HSMV). Under NIR light irradiation, HSMV performs efficient self-propulsion and penetrates into the biofilm within 5 min due to photothermal conversion of asymmetrically distributed AuNPs. The localized thermal (∼45 °C) and thermal-triggered release of vancomycin (Van) leads to an efficient combination of photothermal therapy and chemotherapy in one system. The active motion of HSMV increases the effective distance of photothermal therapy (PTT) and also improves the therapeutic index of the antibiotic, resulting in superior biofilm removal rate (>90%) in vitro. Notably, HSMV can eliminate S. aureus biofilms grown in vivo under 10 min of laser irradiation without damage to healthy tissues. This work may shed light on therapeutic strategies for in vivo treatment of biofilm-associated infections.

Hyperthermia treatment advances for brain tumors

Hyperthermia therapy (HT) of cancer is a well-known treatment approach. With the advent of new technologies, HT approaches are now important for the treatment of brain tumors. We review current clinical applications of HT in neuro-oncology and ongoing preclinical research aiming to advance HT approaches to clinical practice. Laser interstitial thermal therapy (LITT) is currently the most widely utilized thermal ablation approach in clinical practice mainly for the treatment of recurrent or deep-seated tumors in the brain. Magnetic hyperthermia therapy (MHT), which relies on the use of magnetic nanoparticles (MNPs) and alternating magnetic fields (AMFs), is a new quite promising HT treatment approach for brain tumors. Initial MHT clinical studies in combination with fractionated radiation therapy (RT) in patients have been completed in Europe with encouraging results. Another combination treatment with HT that warrants further investigation is immunotherapy. HT approaches for brain tumors will continue to a play an important role in neuro-oncology.

Low-intensity light-induced drug release from a dual delivery system comprising of a drug loaded liposome and a photosensitive conjugate

This study reports the development of a binary drug delivery system consisting of charged liposomes and an oppositely charged peptide-photosensitiser conjugate. Liposomes were prepared with phosphatidyl-l-serine as a negatively charged lipid. Calcein, a fluorophore marker, and doxorubicin, an anticancer drug, were used as model hydrophilic loads. The conjugate consisted of a positively charged arginine-rich peptide synthesised by solid-phase peptide synthesis, and a phthalocyanine derivative with characteristic absorption around 685 nm. Illumination of the binary system with far-red light of 12-15 mW/cm² intensity resulted in 5- to 15-fold increase in release of payloads from the liposomes. The mechanism of drug release was based on photosensitised oxidation of lipids destabilising the liposomal membrane. The cytotoxicity of the liposomes loaded with doxorubicin was tested on B16-F10 melanoma and Y79 retinoblastoma cells. The cytotoxicity of the illuminated binary system in melanoma cell line was significantly higher as compared to the system without illumination. The components of the binary system can be individually prepared and stored with greater storage stability. However, their combination will allow for substantial release of hydrophilic payload from the liposomes under externally applied light.

Effects of Far-infrared Ray on Temozolomide-treated Glioma in Rats

BACKGROUND/AIM

Malignant glioma is a rapidly progressive primary brain cancer. The aim of the study was to investigate the effect of far-infrared ray (FIR) on temozolomide (TMZ)-treated glioma in rats.

MATERIALS AND METHODS

Male, 8-week old, Fischer 344 inbred rats with glioma were randomly divided into three study groups (20 rats in each group). The control group received saline only once daily for 5 days. The TMZ group received TMZ (30 mg/kg) once daily for 5 days. The TMZ plus FIR group received TMZ (30 mg/kg) once daily for 5 days and infrared-c irradiation of 40 min twice daily for 4 weeks. The relative tumor fold and the expression of hypoxia-induced factor-1α (HIF-1α) and vascular endothelial growth factor (VEGF) were compared using one-way ANOVA at the end of study.

RESULTS

The relative tumor fold of the TMZ+FIR group was significantly higher compared to the control group, and was borderline higher compared to the TMZ group at Day 7. The relative tumor fold of TMZ+FIR group was significantly higher compared to the control group and the TMZ group at Days 14, 21 and 28. HIF-1α expression of TMZ+FIR group was borderline higher compared to the control group at Day 28. The VEGF expression of TMZ+FIR group was significantly higher compared to the control group and the TMZ group at Day 28.

CONCLUSION

FIR might increase the growth of glioma under TMZ treatment in rats possibly via increasing VEGF expression, but not HIF-1α expression.

Translational Multi-Disciplinary Approach for the Drug and Gene Delivery Systems for Cancer Treatment

Over the last several decades, nanoparticulate delivery systems have emerged as advanced drug and gene delivery tools for cancer therapy. However, their translation into clinical use still poses major challenges. Even though many innovative nanoparticulate approaches have shown very positive results both in vitro and in vivo, few of them have found a place in clinical practice. Possible factors responsible for the existing gap in the translation of nanomedicine to clinical practice may include oversimplification of enhanced permeability and retention effect, lack of correlation between the in vivo animal data vs their translation in human, and challenging multiple biological steps experienced during systemic delivery of nanomedicine. Understanding these challenges and coming up with solutions to overcome them is an important step in effective translation of nanomedicine into clinical practice. This review focuses on advancements in the field of nanomedicine used for anti-cancer therapy, including passive targeting, active targeting, and stimuli-controlled delivery. The review further reveals some of the challenges that are currently faced by pharmaceutical scientists in translation of nanomedicine; these include lack of adequate models for preclinical testing that can predict efficacy in humans, absence of appropriate regulatory guidelines for their approval processes, and difficulty in scale-up of the manufacturing of nanodrug delivery systems. A better understanding of these challenges will help us in filling the gap between the bench and bedside in cancer therapy.

Gold nanorod-encapsulated biodegradable polymeric matrix for combined photothermal and chemo-cancer therapy

PURPOSE

A biocompatible nanocomplex system co-encapsulated with gold nanorods (AuNRs) and doxorubicin (DOX) was investigated for its potentials on the combined photothermal- and chemotherapy.

MATERIALS AND METHODS

Hydrophobic AuNRs were synthesized by the hexadecyltrimethyl-ammonium bromide (CTAB)-mediated seed growth method, and then, they received two-step surface modifications of polyethylene glycol (PEG) and dodecane. The AuNR/DOX/poly(lactic-co-glycolic acid) (PLGA) nanocomplexes were prepared by emulsifying DOX, AuNR, and PLGA into aqueous polyvinyl alcohol solution by sonication. Human serum albumin (HSA) was used to coat the nanocomplexes to afford HSA/AuNR/DOX-PLGA (HADP). Size and surface potential of the HADP nanocomplexes were determined by using a Zetasizer. Cytotoxicity and cellular uptake of the HADP were analyzed by using MTT assay and flow cytometry, respectively. In vitro anticancer effects of the HADP were studied on various cancer cell lines. To assess the therapeutic efficacy, CT26 tumor-bearing mice were intravenously administered with HADP nanocomplexes and laser treatments, followed by monitoring of the tumor growth and body weight.

RESULTS

Size and surface potential of the HADP nanocomplexes were 245.8 nm and -8.6 mV, respectively. Strong photothermal effects were verified on the AuNR-loaded PLGA nanoparticles (NPs) in vitro. Rapid and repeated drug release from the HADP nanocomplexes was successfully achieved by near-infrared (NIR) irradiations. HSA significantly promoted cellular uptake of the HADP nanocomplexes to murine colon cancer cells as demonstrated by cell imaging and flow cytometric studies. By combining photothermal and chemotherapy, the HADP nanocomplexes exhibited strong synergistic anticancer effects in vitro and in vivo.

CONCLUSION

An NIR-triggered drug release system by encapsulating hydrophobic AuNR and DOX inside the PLGA NPs has been successfully prepared in this study. The HADP NPs show promising combined photothermal- and chemotherapeutic effects without inducing undesired side effects on a murine colon cancer animal model.

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.

Laser Immunotherapy in Combination with Perdurable PD-1 Blocking for the Treatment of Metastatic Tumors

A convenient and feasible therapeutic strategy for malignant and metastatic tumors was constructed here by combining photothermal ablation (PTA)-based laser immunotherapy with perdurable PD-1 blockade immunotherapy. Hollow gold nanoshells (HAuNS, a photothermal agent) and AUNP12 (an anti PD-1 peptide, APP) were co-encapsulated into poly(lactic- co-glycolic) acid (PLGA) nanoparticles. Unlike monoclonal PD-1/PD-L1 antibodies, PD-1 peptide inhibitor shows lower cost and immunotoxicity but needs frequent administration due to its rapid clearance in vivo. Our data here showed that the formed HAuNS- and APP-loaded PLGA nanoparticles (AA@PN) could maintain release periods of up to 40 days for the peptide, and a single intratumoral injection of AA@PN could replace the frequent administration of free APP. After the administration of AA@PN and irradiation with a near-infrared laser at the tumor site, an excellent killing effect on the primary tumor cells was achieved by the PTA. The nanoparticles also played a vaccine-like role under the adjuvant of cytosine-phospho-guanine (CpG) oligodeoxynucleotide and generated a localized antitumor-immune response. Furthermore, sustained APP release with laser-dependent transient triggering could induce the blockage of PD-1/PD-L1 pathway to activate T cells, thus subsequently generating a systemic immune response. Our data demonstrated that the PTA combined with perdurable PD-1 blocking could efficiently eradicate the primary tumors and inhibit the growth of metastatic tumors as well as their formation. The present study provides a promising therapeutic strategy for the treatment of advanced cancer with metastasis and presents a valuable reference for obtaining better outcomes in clinical cancer immunotherapy.

Nanoscale and Macroscale Scaffolds with Controlled-Release Polymeric Systems for Dental Craniomaxillofacial Tissue Engineering

Tremendous progress in stem cell biology has resulted in a major current focus on effective modalities to promote directed cellular behavior for clinical therapy. The fundamental principles of tissue engineering are aimed at providing soluble and insoluble biological cues to promote these directed biological responses. Better understanding of extracellular matrix functions is ensuring optimal adhesive substrates to promote cell mobility and a suitable physical niche to direct stem cell responses. Further, appreciation of the roles of matrix constituents as morphogen cues, termed matrikines or matricryptins, are also now being directly exploited in biomaterial design. These insoluble topological cues can be presented at both micro- and nanoscales with specific fabrication techniques. Progress in development and molecular biology has described key roles for a range of biological molecules, such as proteins, lipids, and nucleic acids, to serve as morphogens promoting directed behavior in stem cells. Controlled-release systems involving encapsulation of bioactive agents within polymeric carriers are enabling utilization of soluble cues. Using our efforts at dental craniofacial tissue engineering, this narrative review focuses on outlining specific biomaterial fabrication techniques, such as electrospinning, gas foaming, and 3D printing used in combination with polymeric nano- or microspheres. These avenues are providing unprecedented therapeutic opportunities for precision bioengineering for regenerative applications.

Biodegradable Polymeric Nanoparticles for Therapeutic Cancer Treatments

Polymeric nanoparticles have tremendous potential to improve the efficacy of therapeutic cancer treatments by facilitating targeted delivery to a desired site. The physical and chemical properties of polymers can be tuned to accomplish delivery across the multiple biological barriers required to reach diverse subsets of cells. The use of biodegradable polymers as nanocarriers is especially attractive, as these materials can be designed to break down in physiological conditions and engineered to exhibit triggered functionality when at a particular location or activated by an external source. We present how biodegradable polymers can be engineered as drug delivery systems to target the tumor microenvironment in multiple ways. These nanomedicines can target cancer cells directly, the blood vessels that supply the nutrients and oxygen that support tumor growth, and immune cells to promote anticancer immunotherapy.

MSN-on-a-Chip: Cell-Based Screenings Made Possible on a Small-Molecule Microarray of Native Natural Products

Standard small-molecule microarrays (SMMs) are not well-suited for cell-based screening assays. Of the few attempts made thus far to render SMMs cell-compatible, all encountered major limitations. Here we report the first mesoporous silica nanoparticle (MSN)-on-a-chip platform capable of allowing high-throughput cell-based screening to be conducted on SMMs. By making use of a glass surface on which hundreds of MSNs, each encapsulated with a different native natural product, were immobilized in spatially defined manner, followed by on-chip mammalian cell growth and on-demand compound release, high-content screening was successfully carried out with readily available phenotypic detection methods. By combining this new MSN-on-a-chip system with small interfering RNA technology for the first time, we discovered that (+)-usniacin possesses synergistic inhibitory properties similar to those of olaparib (an FDA-approved drug) in BRCA1-knockdown cancer cells.

Blue light-induced apoptosis of human promyelocytic leukemia cells via the mitochondrial-mediated signaling pathway

Acute promyelocytic leukemia is frequently associated with dizziness, fever, nausea, hematochezia and anemia. Blue light, or light with wavelengths of 400–480 nm, transmits high levels of energy. The aim of the present study was to determine the pro-apoptotic effects of blue light (wavelength, 456 nm; radiation power, 0.25 mW/cm²) and the underlying mechanisms in a human promyelocytic leukemia cell line (HL60). Blue light reduced the viability and enhanced the mortality of HL60 cells in a time-dependent manner. Exposure to blue light for 24 h caused depolarization of the mitochondrial membrane potential and the overproduction of reactive oxygen species in HL60 cells. In a nude mouse model, 9-day exposure to blue light markedly suppressed the growth of HL60-xenografted tumors; however, it had no effect on hepatic and renal tissues. In addition, blue light abrogated the expression of B-cell lymphoma (Bcl)-2 and Bcl extra-long, while enhancing the levels of Bcl-2-associated X protein, cytochrome c, and cleaved caspases-3 and −9 in tumor tissues. The results suggested that the pro-apoptotic effects of blue light in human promyelocytic leukemia cells may be associated with the mitochondrial apoptosis signaling pathway.

A multifunctional nanoplatform for cancer chemo-photothermal synergistic therapy and overcoming multidrug resistance

A multifunctional nanoplatform could overcome multidrug resistance and showed cancer chemo-photothermal synergistic therapy with the near-infrared irradiation.

Gold nanocage decorated pH-sensitive micelle for highly effective photothermo-chemotherapy and photoacoustic imaging

A pH-sensitive copolymer PAsp(DIP)-b-PAsp(MEA) (PDPM) was synthesized and self-assembled to micelle loading chemotherapeutic drug doxorubicin (DOX) and introducing a gold nanocage structure for photothermo-chemotherapy and photoacoustic imaging. After further surface modification with polyethylene glycol (PEG), the DOX-loaded pH-sensitive gold nanocage (D-PGNC) around 100 nm possessed a uniform spherical structure with a pH-sensitive core of PAsp(DIP) incorporating DOX, an interlayer crosslinked via disulfide bonds and decorated with discontinuous gold shell, and a PEG corona. The release of DOX from D-PGNC was turned off in bloodstream due to the cross-linking and gold decoration of interlayer but turned on inside tumor tissue by multiple stimulations including the low pH value of tumor tissue (≈6.8), the low lysosomal pH value of cancer cells (≈5.0) and near-infrared (NIR) irradiation. The gold nanocage receiving NIR irradiation could generate hyperthermia to ablate tumor cells. Moreover, the photoacoustic (PA) imaging and analysis of DOX fluorescence inside tumor tissue demonstrated that photothermal therapy based on the gold nanocage effectively drove DOX penetration inside tumor. Owing to the rapid intratumor release and deep tissue penetration of drug favorable for killing cancer cells survived the photothermal therapy, the combined therapy based on D-PGNC via NIR irradiation exhibited a synergistic treatment effect superior to either chemotherapy or NIR-induced photothermal therapy alone.

STATEMENT OF SIGNIFICANCE

The novelty of the manuscript is its multifunctional system which incorporates anticancer drug DOX in its pH-sensitive core and acts as a template to introduce a gold nanocage. This nanomedicine presents potentials of sequestrating drug molecules in blood circulation but releasing them inside tumor upon responding to the acidic microenvironment therein. Exposure to NIR laser further expedited the pH-sensitive DOX release and promoted DOX penetration into cancer tissues far away from the vasculature. Consequently, the combined photothermo-chemotherapy showed synergistic effects to inhibit tumor growth and prolong animal survival in nude mice bearing human SKOV-3 ovarian tumor. Moreover, owing to the decoration with gold nanocage, the tumor accumulation and intratumor diffusion of the micelles were easily trackable using photoacoustic imaging.

Porous Electrospun Fibers with Self-Sealing Functionality: An Enabling Strategy for Trapping Biomacromolecules

Stimuli-responsive porous polymer materials have promising biomedical application due to their ability to trap and release biomacromolecules. In this work, a class of highly porous electrospun fibers is designed using polylactide as the polymer matrix and poly(ethylene oxide) as a porogen. Carbon nanotubes (CNTs) with different concentrations are further impregnated onto the fibers to achieve self-sealing functionality induced by photothermal conversion upon light irradiation. The fibers with 0.4 mg mL-1 of CNTs exhibit the optimum encapsulation efficiency of model biomacromolecules such as dextran, bovine serum albumin, and nucleic acids, although their photothermal conversion ability is slightly lower than the fibers with 0.8 mg mL-1 of CNTs. Interestingly, reversible reopening of the surface pores is accomplished with the degradation of PLA, affording a further possibility for sustained release of biomacromolecules after encapsulation. Effects of CNT loading on fiber morphology, structure, thermal/mechanical properties, degradation, and cell viability are also investigated. This novel class of porous electrospun fibers with self-sealing capability has great potential to serve as an enabling strategy for trapping/release of biomacromolecules with promising applications in, for example, preventing inflammatory diseases by scavenging cytokines from interstitial body fluids.

Gold Nanorod Mediated Chlorhexidine Microparticle Formation and Near-Infrared Light Induced Release

Gold nanorods (GNR) are good light harvesting species for elaboration of near-infrared (NIR) responsive drug delivery systems. Herein, chlorhexidine microparticles are grown directly on the surface of gold nanorods and then stabilized with polyelectrolyte multilayer encapsulation, producing novel composite drug-GNR particles with high drug loading and NIR light sensitivity. Crystallization of chlorhexidine is caused by the ionic strength of the chloride solution that has been demonstrated via formation of a homogeneous porous spherical structure at 0.33 M CaCl₂. By introducing GNRs into the CaCl₂ solution, the nucleation of chlorhexidine molecules and size of produced spheres are affected, since GNRs act as sites for chlorhexidine nucleation. Similarly, when GNRs are replaced by chlorhexidine seeds (5.2 ± 1.7 μm), a core-shell crystal structure is observed. The encapsulated GNR/chlorhexidine composites are responsive to NIR light (840 nm) that increases the temperature at the chlorhexidine crystals, followed by microparticle dissolution and rupture of capsules which is illustrated with confocal microscopy and SEM. Furthermore, a stepwise burst release of chlorhexidine can be induced by multiple cycles of NIR light exposure. The GNR/chlorhexidine composites show good biocompatibility and antimicrobial activity. The proposed method of antibacterial drug release may therefore indicate that this NIR responsive chlorhexidine composite may be useful for future clinical applications.

Nanomaterials engineering for drug delivery: a hybridization approach

The last twenty years have witnessed great advances in biology, medicine, and materials science, leading to the development of various nanoparticle (NP)-mediated drug delivery systems. Innovation in materials science has led the generation of biodegradable, biocompatible, stimuli-responsive, and targeted delivery systems. However, currently available nanotherapeutic technologies are not efficient, which has culminated in the failure of their clinical trials. Despite huge efforts devoted to drug delivery nanotherapeutics, only a small amount of the injected material could reach the desired target. One promising strategy to enhance the efficiency of NP drug delivery is to hybridize multiple materials, where each component could play a critical role in an efficient multipurpose delivery system. This review aims to comprehensively cover different techniques, materials, advantages, and drawbacks of various systems to develop hybrid nano-vesicles for drug delivery. Attention is finally given to the hybridization benefits in overcoming the biological barriers for drug delivery. It is believed that the advent of modern nano-formulations for multifunctional hybrid carriers paves the way for future advances to achieve more efficient drug delivery systems.

Nanohybrid magnetic liposome functionalized with hyaluronic acid for enhanced cellular uptake and near-infrared-triggered drug release

The aim of this work is to prepare and evaluate a novel lipid-polymer hybrid liposomal nanoplatform (hyaluronic acid-magnetic nanoparticle-liposomes, HA-MNP-LPs) as a vehicle for targeted delivery and triggered release of an anticancer drug (docetaxel, DTX) in human breast cancer cells. We first synthesize an amphiphilic hyaluronic acid hexadecylamine polymer (HA-C₁₆) to enhance the targeting ability of the hybrid liposome. Next, HA-MNP-LPs are constructed to achieve an average size of 189.93±2.74nm in diameter. In addition, citric acid-coated magnetic nanoparticles (MNPs) are prepared and embedded in the aqueous cores while DTX is encapsulated in the hydrophobic bilayers of the liposomes. Experiments with coumarin 6 loaded hybrid liposomes (C6/HA-MNP-LPs) show that the hybrid liposomes have superior cellular uptake in comparison with the conventional non-targeting liposomes (C6/MNP-LPs), and the result is further confirmed by Prussian blue staining. Under near-infrared laser irradiation (NIR, 808nm), the HA-MNP-LPs aqueous solution can reach 46.7°C in 10min, and the hybrid liposomes released over 20% more drug than the non-irradiated liposomes. Using a combination of photothermal irradiation and chemotherapy, the DTX-loaded hybrid liposomes (DTX/HA-MNP-LPs) significantly enhance therapeutic efficacy, with the IC₅₀ value of 0.69±0.10μg/mL, which is much lower than the values for DTX monotherapy. Consequently, the prepared hybrid nanoplatform may offer a promising drug delivery vehicle with selective targeting and enhanced drug release in treating CD44-overexpressing cancers.

Low molecular weight polyethylenimine-conjugated gold nanospheres: a platform for selective gene therapy controlled by near-infrared light

Aim: Whether PEI2k-HAuNS could promote gene transfection efficiency controlled by near-infrared (NIR) light. Materials & methods: This safe nonviral gene delivery system was obtained by conjugating low molecular weight (2 kDa) polyethylenimine (PEI) onto hollow gold nanospheres (PEI2k-HAuNS). Upon NIR laser irradiation, there was a conspicuous increase both in the in vitro and in vivo transfection achieved by the nanocomplexes. Furthermore, a plasmid encoding the tumor suppressor TP53 (pTP53) was applied to test antitumor activity. Results: The enhanced gene transfection efficiency and therapy of PEI2k-HAuNS were achieved via the mediation of an NIR laser compared with the other treatments in vitro and in vivo. Conclusion: The application of NIR laser irradiated PEI2k-HAuNS can be used as a promising gene delivery systems in vitro and in vivo.

Ultrasensitive Phototriggered Local Anesthesia

An injectable local anesthetic producing repeatable on-demand nerve block would be desirable for pain management. Here we present a phototriggerable device to achieve repeatable and adjustable on-demand local anesthesia in superficial or deep tissues, consisting of gold nanorods attached to low temperature sensitive liposomes (LTSL). The particles were loaded with tetrodotoxin and dexmedetomidine. Near-infrared light (NIR, 808 nm, continuous wave) could heat gold nanorods at low fluence (short duration and low irradiance), leading to rapid release of payload. In vivo, 1-2 min of irradiation at ≤272 mW/cm2 produced repeatable and adjustable on-demand infiltration anesthesia or sciatic nerve blockade with minimal toxicity. The nerve block intensity and duration correlated with the irradiance and duration of the applied light.

Photosensitizer loaded PEG-MoS2–Au hybrids for CT/NIRF imaging-guided stepwise photothermal and photodynamic therapy

We develop X-ray computed tomography/near-infrared fluorescence imaging for visually guiding the photothermal/photodynamic therapy of antitumor nanocomposites (PEG-MoS₂–Au–Ce6), by adsorbing chlorin e6 to the gold nanoparticle-decorated molybdenum disulfide nanosheets.

Externally controlled drug release using a gold nanorod contained composite membrane

Versatile drug delivery devices using nanoporous membranes consisting of gold nanorods and dendrimers have been demonstrated to provide light-triggered on-demand pulsatile release from a reservoir containing highly enriched therapeutics for a real patient's needs. The drug release rate is directly correlated with the temperature increase and irradiated energy of a near-IR laser in both static and fluidic devices. This biocompatible platform for on-demand control was further confirmed by in vitro experiments. Interestingly, different responses to stimuli were obtained from each drug in the absence and presence of NIR light, indicating the versatile potential of our on-demand drug delivery system in less-invasive therapies requiring multi-drug delivery strategies. The enhanced delivery system will improve therapeutic efficacy and reduce side effects through regulation of plasma drug profiles.

An injectable drug-loaded hydrogel based on a supramolecular polymeric prodrug

We reported a novel injectable doxorubicin-loaded hydrogel based on host-guest interaction and Schiff's base reaction. A supramolecular polymeric prodrug was prepared through the inclusion of adamantane-modified doxorubicin into the β-cyclodextrin cavity on the polyaldehyde dextran chain, which was in situ crosslinked by carboxymethyl chitosan.

Far-Red Light-Activatable Prodrug of Paclitaxel for the Combined Effects of Photodynamic Therapy and Site-Specific Paclitaxel Chemotherapy

Paclitaxel (PTX) is one of the most useful chemotherapeutic agents approved for several cancers, including ovarian, breast, pancreatic, and nonsmall cell lung cancer. However, it causes systemic side effects when administered parenterally. Photodynamic therapy (PDT) is a new strategy for treating local cancers using light and photosensitizer. Unfortunately, PDT is often followed by recurrence due to incomplete ablation of tumors. To overcome these problems, we prepared the far-red light-activatable prodrug of PTX by conjugating photosensitizer via singlet oxygen-cleavable aminoacrylate linker. Tubulin polymerization enhancement and cytotoxicity of prodrugs were dramatically reduced. However, once illuminated with far-red light, the prodrug effectively killed SKOV-3 ovarian cancer cells through the combined effects of PDT and locally released PTX. Ours is the first PTX prodrug that can be activated by singlet oxygen using tissue penetrable and clinically useful far-red light, which kills the cancer cells through the combined effects of PDT and site-specific PTX chemotherapy.

"Combo" nanomedicine: Co-delivery of multi-modal therapeutics for efficient, targeted, and safe cancer therapy

The dynamic and versatile nature of diseases such as cancer has been a pivotal challenge for developing efficient and safe therapies. Cancer treatments using a single therapeutic agent often result in limited clinical outcomes due to tumor heterogeneity and drug resistance. Combination therapies using multiple therapeutic modalities can synergistically elevate anti-cancer activity while lowering doses of each agent, hence, reducing side effects. Co-administration of multiple therapeutic agents requires a delivery platform that can normalize pharmacokinetics and pharmacodynamics of the agents, prolong circulation, selectively accumulate, specifically bind to the target, and enable controlled release in target site. Nanomaterials, such as polymeric nanoparticles, gold nanoparticles/cages/shells, and carbon nanomaterials, have the desired properties, and they can mediate therapeutic effects different from those generated by small molecule drugs (e.g., gene therapy, photothermal therapy, photodynamic therapy, and radiotherapy). This review aims to provide an overview of developing multi-modal therapies using nanomaterials ("combo" nanomedicine) along with the rationale, up-to-date progress, further considerations, and the crucial roles of interdisciplinary approaches.

Reinvention of chemotherapy: drug conjugates and nanoparticles

PURPOSE OF REVIEW

Recent advances in nanotechnology have addressed some of the issues related to lack of selectivity and nonspecific toxicities associated with conventional chemotherapy. Nanoparticles are therapeutic carriers that can be fine tuned for specific application and for passive or active tumor targeting.

RECENT FINDINGS

Although the nanoparticle field is rapidly expanding, there are to date only six nanoparticle-based drug delivery platforms and two antibody-drug conjugates that are clinically approved for cancer therapy. Here, we review the clinical data of liposomal anthracyclines, nanoparticle formulations of paclitaxel and trastuzumab emtansine. We then briefly comment on efficacy and safety issues of nanoparticles, as well as on the next-generation nanoparticles for cancer therapy.

SUMMARY

The emerging development of cancer nanotechnology offers the opportunity of reinvestigating the potential of cytotoxic agents, improving tumor targeting and drug delivery, leading to better safety profile and antitumor activity. Adding specificity to nanoparticles may allow personalization of cancer therapy using chemotherapy.

Phototriggered Local Anesthesia

We report a phototriggerable formulation enabling in vivo repeated and on-demand anesthesia with minimal toxicity. Gold nanorods (GNRs) that can convert near-infrared (NIR) light into heat were attached to liposomes (Lip-GNRs), enabling light-triggered phase transition of their lipid bilayers with a consequent release of payload. Lip-GNRs containing the site 1 sodium channel blocker tetrodotoxin and the α2-adrenergic agonist dexmedetomidine (Lip-GNR-TD) were injected subcutaneously in the rat footpad. Irradiation with an 808 nm continuous wave NIR laser produced on-demand and repeated infiltration anesthesia in the rat footpad in proportion to the irradiance, with minimal toxicity. The ability to achieve on-demand and repeated local anesthesia could be very beneficial in the management of pain.

One-pot synthesis of PEGylated plasmonic MoO(3-x) hollow nanospheres for photoacoustic imaging guided chemo-photothermal combinational therapy of cancer

Engineering design of plasmonic nanomaterials as on-demand theranostic nanoagents with imaging, drug carrier, and photothermal therapy (PTT) functions have profound impact on treatment of cancer. Here, a facile 'one-pot' template-free hydrothermal route was firstly developed for synthesis of plasmonic oxygen deficiency molybdenum oxide hollow nanospheres functionalized by poly(ethylene glycol) (PEG-MoO(3-x) HNSs). The as-prepared PEG-MoO(3-x) HNSs not only have good biocompatibility but also exhibit obvious localized surface plasmon resonance (LSPR) absorption in the near-infrared (NIR) region. Especially, due to its intrinsic mesoporous properties and effective photothermal conversion efficiency upon 808-nm NIR laser irradiation, the PEG-MoO(3-x) HNSs can be applied as a pH/NIR laser dual-responsive camptothecin (CPT) drug delivery nanoplatform for chemotherapy as well as PTT to cancer cells. A remarkably improved synergistic therapeutic effect to pancreatic (PANC-1) tumor-bearing mice was obtained compared to the result of chemotherapy or PTT alone. Apart from its application for drug delivery, the PEG-MoO(3-x) HNSs can also be employed as an effective contrast nanoagent for photoacoustic (PAT) imaging because of its high NIR absorption, making it promising as a theranostic nanoagent for PAT imaging-guided chemo-photothermal combinational cancer therapy in the nanomedicine field.

One-Step Generation of Multifunctional Polyelectrolyte Microcapsules via Nanoscale Interfacial Complexation in Emulsion (NICE)

Polyelectrolyte microcapsules represent versatile stimuli-responsive structures that enable the encapsulation, protection, and release of active agents. Their conventional preparation methods, however, tend to be time-consuming, yield low encapsulation efficiency, and seldom allow for the dual incorporation of hydrophilic and hydrophobic materials, limiting their widespread utilization. In this work, we present a method to fabricate stimuli-responsive polyelectrolyte microcapsules in one step based on nanoscale interfacial complexation in emulsions (NICE) followed by spontaneous droplet hatching. NICE microcapsules can incorporate both hydrophilic and hydrophobic materials and also can be induced to trigger the release of encapsulated materials by changes in the solution pH or ionic strength. We also show that NICE microcapsules can be functionalized with nanomaterials to exhibit useful functionality, such as response to a magnetic field and disassembly in response to light. NICE represents a potentially transformative method to prepare multifunctional nanoengineered polyelectrolyte microcapsules for various applications such as drug delivery and cell mimicry.