Hongling Zhang

Synergistic enhancement of cancer therapy using a combination of docetaxel and photothermal ablation induced by single-walled carbon nanotubes.

Background Single-walled carbon nanotubes (SWNT) are poorly soluble in water, so their applications are limited. Therefore, aqueous solutions of SWNT, designed by noncovalent functionalization and without toxicity, are required for biomedical applications. Methods In this study, we conjugated docetaxel with SWNT via π-π accumulation and used a surfactant to functionalize SWNT noncovalently. The SWNT were then conjugated with docetaxel (DTX-SWNT) and linked with NGR (Asn-Gly-Arg) peptide, which targets tumor angiogenesis, to obtain a water-soluble and tumor-targeting SWNT-NGR-DTX drug delivery system. Results SWNT-NGR-DTX showed higher efficacy than docetaxel in suppressing tumor growth in a cultured PC3 cell line in vitro and in a murine S180 cancer model. Tumor volumes in the S180 mouse model decreased considerably under near-infrared radiation compared with the control group. Conclusion The SWNT-NGR-DTX drug delivery system may be promising for high treatment efficacy with minimal side effects in future cancer therapy.

Tumor-targeted and multi-stimuli responsive drug delivery system for near-infrared light induced chemo-phototherapy and photoacoustic tomography

UNLABELLED In this work, a tumor-targeted and multi-stimuli responsive drug delivery system has been developed for combining photoacoustic tomography imaging with chemo-phototherapy. We utilized a kind of near infrared (NIR) resonant material-hollow mesoporous copper sulfide nanoparticles (HMCuS NPs) to encapsulate doxorubicin (DOX). After that, the outer surface of HMCuS NPs was capped with multifunctional hyaluronic acid (HA) simultaneously as smart gatekeeper as well as tumor targeting moiety. Herein, HMCuS-HA could serve as a powerful contrast agent for photoacoustic tomography (PAT) to guide chemo-phototherapy by providing the identification of cancerous lesions. In vitro and in vivo studies, the nanoplatform (DOX/HMCuS-HA) pinpointed MCF-7 cells via CD44 receptor-mediated endocytosis pathway. Subsequently, intracellular enzyme-responsive controlled drug release would take place in lysosome after the HA degradation by hyaluronidase. Under near infrared (NIR) light irradiation, HMCuS NPs could not only effectively convert NIR light into heat for photothermal therapy, but also generate high levels of reactive oxygen species (ROS) for photodynamic therapy. In addition, NIR light and low pH environment could facilitate intracellular tunable drug release with spatial/temporal resolution, and thus synergistic combination of chemo-phototherapy should be simultaneously driven by an 808nm laser irradiation, which brought out an outstanding therapeutic effect. In vivo optical imaging demonstrated that HMCuS-HA significantly enhanced targeting and accumulation capacity in tumor site. Furthermore, tumor-bearing mice treated with DOX/HMCuS-HA under NIR irradiation (808nm, 2W/cm(2), 0.5min) in vivo displayed the highest inhibition ratio of about 88.9%. Taken together, our present study of the tumor-targeted and multi-stimuli responsive drug delivery system provides new insights into multimodality theranostic applications in cancer treatment. STATEMENT OF SIGNIFICANCE Until now, chemotherapy is still the major therapeutic approach applied in oncology. Despite their pharmacologically efficacy in cancer treatments, most chemotherapeutic agents without tumor-specific targeting ability have brought out serious toxicities to normal tissues. This study provides a promising near infrared (NIR) resonant material-hollow mesoporous copper sulfide nanoparticles (HMCuS NPs) with capping of multifunctional hyaluronic acid (HA) simultaneously as smart gatekeeper as well as tumor targeting moiety to address the above problem. After the nanoplatform (DOX/HMCuS-HA) pinpointed breast cancer cells via CD44 receptor-mediated endocytosis pathway, intracellular multi-stimuli responsive controlled drug release would take place with remarkable spatial/temporal resolution. Then photoacoustic tomography (PAT) and synergistic combination of chemo-phototherapy would be simultaneously driven by the same NIR irradiation in a coordinated way, which brought out an outstanding theranostic effect. This work can arouse broad interests among researchers in the fields of nanomedicine, nanotechnology, and drug delivery system.

The tumor-targeting core-shell structured DTX-loaded PLGA@Au nanoparticles for chemo-photothermal therapy and X-ray imaging.

In this study, an organic-inorganic hybrid nanocomposite was synthesized by deposition of Au onto the surface of docetaxel (DTX)-loaded poly (lactide-co-glycolide) (PLGA) nanoparticle cores to form the core-shell structured DTX-loaded PLGA@Au nanoparticles. The tumor targeting peptide, angiopep-2, was then introduced onto the gold nanoshell through Au-S bond, achieving drug delivery with active targeting capability. This novel system allowed combined chemotherapy and thermal therapy for cancer, resulting from DTX and gold nanoshell. The formation of tumor-targeting gold nanoshell surrounding PLGA nanocore, designated as ANG/GS/PLGA/DTX NPs, was confirmed by its surface plasmon resonance (SPR) band in the UV-Vis spectrum and by a transmission electron microscope (TEM). The release profiles of DTX from this system showed strong dependence on near-infrared (NIR) laser. Compared with DTX alone, the ANG/GS/PLGA/DTX NPs afforded much higher anti-tumor efficiency without obvious toxic effects. Besides, it also showed potential X-ray imaging ability. These results demonstrated that the tumor-targeting core-shell structured DTX-loaded PLGA@Au nanoparticles could be used as a multifunctional nanomaterial system with NIR-triggered drug-releasing properties for tumor-targeted chemo-photothermal therapy and theranostics.

Targeted Imaging and Chemo‐Phototherapy of Brain Cancer by a Multifunctional Drug Delivery System

The aim of this study was to develop multifunctional poly lactide-co-glycolide (PLGA) nanoparticles with the ability to simultaneously deliver indocyanine green (ICG) and docetaxel (DTX) to the brain by surface decoration with the brain-targeting peptide angiopep-2 to achieve combined chemo-phototherapy for glioma under near-infrared (NIR) imaging. ICG was selected as a near-infrared imaging and phototherapy agent and DTX was employed as a chemotherapeutic agent. ICG and DTX were simultaneously incorporated into PLGA nanoparticles with higher stability. These nanoparticles were further decorated with angiopep-2 via the outer maleimide group of 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[methoxy(polyethyleneglycol)-2000]-maleinimide incorporated in the nanoparticles. The NIR image-guided chemo-phototherapy of the angiopep-2 modified PLGA/DTX/ICG nanoparticles (ANG/PLGA/DTX/ICG NPs) not only highly induced U87MG cell death in vitro, but also efficiently prolonged the life span of the brain orthotopic U87MG glioma xenograft-bearing mice in vivo. Thus, this study suggests that ANG/PLGA/DTX/ICG NPs have the potential for combinatorial chemotherapy and phototherapy for glioma.

Co-delivery of doxorubicin and siRNA for glioma therapy by a brain targeting system: angiopep-2-modified poly(lactic-co-glycolic acid) nanoparticles

Abstract It is very challenging to treat brain cancer because of the blood–brain barrier (BBB) restricting therapeutic drug or gene to access the brain. In this research project, angiopep-2 (ANG) was used as a brain-targeted peptide for preparing multifunctional ANG-modified poly(lactic-co-glycolic acid) (PLGA) nanoparticles (NPs), which encapsulated both doxorubicin (DOX) and epidermal growth factor receptor (EGFR) siRNA, designated as ANG/PLGA/DOX/siRNA. This system could efficiently deliver DOX and siRNA into U87MG cells leading to significant cell inhibition, apoptosis and EGFR silencing in vitro. It demonstrated that this drug system was capable of penetrating the BBB in vivo, resulting in more drugs accumulation in the brain. The animal study using the brain orthotopic U87MG glioma xenograft model indicated that the ANG-targeted co-delivery of DOX and EGFR siRNA resulted in not only the prolongation of the life span of the glioma-bearing mice but also an obvious cell apoptosis in glioma tissue.

Near-infrared-triggered in situ hybrid hydrogel system for synergistic cancer therapy

As one of the most frequently used chemotherapeutic drugs, doxorubicin (DOX) is accompanied by low accumulation in tumors and severe dose-limiting side effects with systemic administration, which limits its therapeutic index. In this work, a novel and injectable in situ photo-sensitive inorganic/organic hybrid hydrogel as a localized drug-delivery system was examined. It explored poly(ethylene glycol) double acrylates (PEGDA) as a polymeric matrix, DOX as a model drug, a TiO2@MWCNT nanocomposite as the photoinitiator and photosensitizer-photothermal agent for tumor therapy possessing a multi-mechanism using a single NIR laser. Briefly, a PEGDA solution containing DOX and TiO2@MWCNTs was injected into a tumor and rapidly gelled in vivo via a photo-crosslinking action triggered by a NIR laser. DOX release from the DOX/TiO2@MWCNTs/PEGDA hydrogel was sustained and long-lasting, over 10 days, indicating that the PEGDA gel acted as a drug depot. Simultaneously, a NIR laser light was adopted which can be absorbed and converted into reactive oxygen species (ROS) or local hyperthermia by TiO2@MWCNTs, leading to tumor cell death. This DOX/TiO2@MWCNTs/PEGDA hydrogel exhibited remarkable anti-proliferative activities against MCF-7 cancer cells in vitro. Experiments in vivo showed that a single intratumoral injection of this hydrogel with 808 nm laser irradiation was the most effective among all DOX formulations in the tumor-bearing mice models. There was a relatively small DOX distribution in normal tissues and much lower systemic toxicity than the control group (DOX-only). In general, it is believed that the novel photo-sensitive hybrid hydrogel system prepared in this study can afford high drug-loading, sustained and stable drug release, as well as repeated phototherapy of the tumor with the administration of a single dose.

Manganese dioxide nanosheets-based redox/pH-responsive drug delivery system for cancer theranostic application

The aim of this study was to construct redox- and pH-responsive degradable manganese dioxide (MnO2) nanosheets for cancer theranostic application. The small MnO2 nanosheets were synthesized, and then functionalized by hyaluronic acid (HA), demonstrating excellent stability and tumor-targeting ability. Cisplatin (cis-diamminedichloroplatinum [CDDP]) was absorbed by the nanosheets through a physical action, which was designed as MnO2/HA/CDDP. The prepared MnO2/HA/CDDP formulation was able to efficiently deliver CDDP to tumor cells in vitro and in vivo, resulting in improved therapeutic efficiency. Subsequently, they were triggered by lower pH and higher level of reduced glutathione to generate Mn2+, enabling magnetic resonance imaging. The smart multifunctional system combining efficient magnetic resonance imaging and chemotherapy has the potential to be used as a tumor-targeting theranostic nanomedicine.

Preparation and cytotoxicity of 2-methoxyestradiol-loaded solid lipid nanoparticles.

The objective of this study was to prepare 2-methoxyestradiol (2-ME)-loaded solid lipid nanoparticles (SLN) by hot homogenization–ultrasonication and evaluate their cytotoxicity on three cell lines, breast cancer [Michigan Cancer Foundation-7 (MCF-7)], prostatic carcinoma (PC-3), and glioma (SK-N-SH), by the sulforhodamineB method. The particle sizes and zeta potentials of the prepared SLN were around 120 nm and −40 mV, respectively. Differential scanning calorimetry (DSC) measurements revealed that the monostearin and 2-ME existed in solid and amorphous states in the SLN prepared, respectively. The high drug entrapment efficiency (>85%) indicated that most 2-ME was incorporated in the SLN. An in-vitro drug release study showed that 2-ME was released from the SLN in a slow but time-dependent manner. The cytotoxicity of 2-ME in SLN on each cell line was significantly enhanced compared with the solution. 2-ME SLN composed of Tween80 was approximately 17-fold more effective on PC-3 cells and 6.7-fold more effective on SK-N-SH cells than in the solution, whereas a lower sensitivity was achieved on MCF-7 cells. In each cell line, the cellular uptake percentages of 2-ME in SLN were much higher than the solution, respectively. In addition, surfactants may exert different effects on the cytotoxicity of 2-ME SLN depending on the cell line. The above assay demonstrated that SLN could significantly enhance the cytotoxicity of 2-ME compared with the free drug because of the increased cellular internalization and concentration of 2-ME. The results suggested that SLN could be an excellent carrier candidate to entrap 2-ME for improving the effectiveness of tumor chemotherapy.

Multifunctional nanoplatform for enhanced photodynamic cancer therapy and magnetic resonance imaging

Co-delivery of photosensitizers and synergistic agents by one single nanoplatform is interesting for enhancing photodynamic therapy (PDT) of cancer. Here, a multifunctional nanoplatform for enhanced photodynamic therapy and magnetic resonance imaging of cancer was constructed. The poly (lactide-co-glycolide) (PLGA) nanoparticles (NPs) loaded with hematoporphyrin monomethyl ether (HMME) were coated with multifunctional manganese dioxide (MnO2) shells, which were designed as PLGA/HMME@MnO2 NPs. Once the NPs were effectively taken up by tumor cells, the intracellular H2O2 was catalysed by the MnO2 shells to generate O2. Meanwhile, the higher glutathione (GSH) promoted the degradation of MnO2 into Mn2+ ions with the ability of magnetic resonance (MR) imaging. After the degradation of outer layer, the release of photosensitizer was promoted. Under irradiation, the released HMME produced cytotoxic reactive oxygen species (ROS) to damage the tumor cells when the O2 was generated in the hypoxic tumor site. Furthermore, the decreased GSH level further inhibited the consumption of the produced ROS, which greatly enhanced the PDT efficacy. Therefore, this study suggested that this multifunctional system has the potential for enhanced photodynamic therapy and magnetic resonance imaging.

Single-Walled Carbon Nanotubes Mediated Neovascularity Targeted Antitumor Drug Delivery System

PURPOSE The aim of this study was to prepare a new neovascularity targeting antitumor drug delivery system mediated by single-walled carbon nanotubes (SWNTs). METHODS In this study, antiangiogenesis agent 2-methoxyestradiol was loaded by SWNTs via π~π accumulation. The SWNTs were then linked with NGR (Asn-Gly-Arg) peptide, which could target tumor angiogenesis. This drug delivery system was characterized by transmission electron microscope, scanning electron microscopy, and atomic force microscope analysis. The suppression efficacy of tumor growth in cultured breast cancer cell line was evaluated by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. The in vivo antitumor activity was evaluated on the Sarcoma (S180) tumor-bearing mice model. RESULTS The characteristics of this drug delivery system showed that the particle of complex was 190 ± 4.3 nm in size distribution and 23.56 ± 2.03 mV in zeta potential. The inhibition ratio of this SWNTs drug delivery system at 24, 48, and 72 h was about 57.7%, 83.6%, and 88.2%. Compared with normal saline group, the relative tumor volumes in the 2ME, SWNTs-2ME, and NGR-SWNTs-2ME groups were decreased 1 week after administration. CONCLUSION This novel neovascularity targeting drug delivery system containing NGR-SWNTs-2ME may be beneficial to improve treatment efficacy and minimize side effects in future cancer therapy.