An RGD-modified hollow silica@Au core/shell nanoplatform for tumor combination therapy

Doxorubicin and Anti-PD-L1 Antibody Conjugated Gold Nanoparticles for Colorectal Cancer Photochemotherapy

Colorectal cancer (CRC) is the third leading cause of cancer-related death worldwide. The prognosis and overall survival of CRC are known to be significantly correlated with the overexpression of PD-L1. Since combination therapies can significantly improve therapeutic efficacy, we constructed doxorubicin (DOX) conjugated and anti-PD-L1 targeting gold nanoparticles (PD-L1-AuNP-DOX) for the targeted chemo-photothermal therapy of CRC. DOX and anti-PD-L1 antibody were conjugated to the α-terminal end group of lipoic acid polyethylene glycol N-hydroxysuccinimide (LA-PEG-NHS) using an amide linkage, and PD-L1-AuNP-DOX was constructed by linking LA-PEG-DOX, LA-PEG-PD-L1, and a short PEG chain on the surface of AuNP using thiol-Au covalent bonds. Physicochemical characterizations and biological studies of PD-L1-AuNP-DOX were performed in the presence of near-infrared (NIR) irradiation (biologic studies were conducted using cellular uptake, apoptosis, and cell cycle assays in CT-26 cells). PD-L1-AuNP-DOX (40.0 ± 3.1 nm) was successfully constructed and facilitated the efficient intracellular uptake of DOX as evidenced by pronounced apoptotic effects (66.0%) in CT-26 cells. PD-L1-AuNP-DOX treatment plus NIR irradiation significantly and synergistically suppressed the in vitro proliferation of CT-26 cells by increasing apoptosis and cell cycle arrest. The study demonstrates that PD-L1-AuNP-DOX in combination with synergistic targeted chemo-photothermal therapy has a considerable potential for the treatment of localized CRC.

Poly(amidoamine) Dendrimer-Coordinated Copper(II) Complexes as a Theranostic Nanoplatform for the Radiotherapy-Enhanced Magnetic Resonance Imaging and Chemotherapy of Tumors and Tumor Metastasis

The development of a powerful nanoplatform to realize the simultaneous therapy and diagnosis of cancer using a similar element for theranostics remains a critical challenge. Herein, we report such a theranostic nanoplatform based on pyridine (Pyr)-functionalized generation 5 (G5) poly(amidoamine) dendrimers complexed with copper(II) (Cu(II)) for radiotherapy-enhanced T₁-weighted magnetic resonance (MR) imaging and the synergistic radio-chemotherapy of both tumors and tumor metastasis. In this study, amine-terminated G5 dendrimers were covalently linked with 2-pyridinecarboxylic acid, acetylated to neutralize their remaining terminal amines, and complexed with Cu(II) through both the internal tertiary amines and the surface Pyr groups to form the G5.NHAc-Pyr/Cu(II) complexes. We show that the complexes are able to inhibit the proliferation of different cancer cell lines with half-maximal inhibitory concentrations ranging from 4 to 10 μM and induce significant cancer cell apoptosis. Due to the presence of Cu(II), the G5.NHAc-Pyr/Cu(II) complexes display an r₁ relaxivity of 0.7024 mM^-1 s^-1, enabling effective in vivo MR imaging of tumor xenografts and lung metastatic nodules. Further, under radiotherapy (RT) conditions, the tumor MR imaging sensitivity can be significantly enhanced, and the G5.NHAc-Pyr/Cu(II) complexes enable the enhanced chemotherapy of both a xenografted tumor model and a blood-vessel metastasis model. With the demonstrated theranostic potential of the dendrimer-Cu(II) nanocomplexes without additional agents or elements for RT-enhanced MR imaging and chemotherapy of tumor and tumor metastasis, this novel Cu(II)-based nanohybrids may hold great promise for the theranostics of different cancer types and metastases.

Core–shell noble-metal@zeolitic-imidazolate-framework nanocarriers with high cancer treatment efficiency in vitro

Core–shell Au@zeolitic-imidazolate-framework nanocarriers with high drug-loading, controlled drug release properties, and high cancer treatment efficiency.

Specific capture and release of circulating tumor cells using a multifunctional nanofiber-integrated microfluidic chip

Aim: To develop a multifunctional nanofibrous mat-embedded microfluidic chip system for specific capture and intact release of circulating tumor cells. Materials & methods: Electrospun polyethylenimine/polyvinyl alcohol nanofibers were functionalized with zwitterions to reduce the nonspecific adhesion of blood cells, followed by modification with arginine-glycine-aspartic acid peptide via an acid-sensitive benzoic imine bond. Results: The nanofiber-embedded microchip can be applied for capturing various types of cancer cells and circulating tumor cells with high efficiency and considerable purity. The captured cancer cells can be released from the nanofibrous substrates within 30 min. Conclusion: The developed multifunctional nanofiber-embedded microfluidic chip may have a great potential for clinical applications.

A multifunctional near-infrared laser-triggered drug delivery system using folic acid conjugated chitosan oligosaccharide encapsulated gold nanorods for targeted chemo-photothermal therapy

FA–COS–TGA–GNRs–DOX have been successfully designed as a drug delivery system for chemo-photothermal combination therapy.

A polydopamine-coated LAPONITE®-stabilized iron oxide nanoplatform for targeted multimodal imaging-guided photothermal cancer therapy

A novel targeted theranostic nanoplatform (LAP–Fe₃O₄@PDA–PEG–PBA) is constructed for magnetic resonance and photoacoustic imaging-guided photothermal therapy of cancer cells overexpressing sialic acid.

Dendrimer-Stabilized Gold Nanoflowers Embedded with Ultrasmall Iron Oxide Nanoparticles for Multimode Imaging-Guided Combination Therapy of Tumors

Development of multifunctional theranostic nanoplatforms with improved diagnostic sensitivity and therapeutic efficiency of tumors still remains a great challenge. A unique multifunctional theranostic nanoplatform based on generation 5 (G5) poly(amidoamine) dendrimer-stabilized gold nanoflowers (NFs) embedded with ultrasmall iron oxide (USIO) nanoparticles (NPs) for multimode T 1-weighted magnetic resonance (MR)/computed tomography (CT)/photoacoustic (PA) imaging-guided combination photothermal therapy (PTT) and radiotherapy (RT) of tumors is reported here. G5 dendrimer-stabilized Au NPs and citric acid-stabilized USIO NPs are separately prepared, the two particles under a certain Fe/Au molar ratio are mixed to form complexes, the complexes are exposed to Au growth solution to form NFs via a seed-mediated manner, and the remaining dendrimer terminal amines are acetylated. The formed dendrimer-stabilized Fe3O4/Au NFs (for short, Fe3O4/Au DSNFs) have a mean diameter of 99.8 nm, display good colloidal stability and cytocompatibility, and exhibit a near-infrared absorption feature. The unique structure and composition of the Fe3O4/Au DSNFs endows them with a high r 1 relaxivity (3.22 mM-1 s-1) and photothermal conversion efficiency (82.7%), affording their uses as a theranostic nanoplatform for multimode MR/CT/PA imaging and combination PTT/RT of tumors with improved therapeutic efficacy, which is important for translational nanomedicine applications.

Development of Multifunctional Polydopamine Nanoparticles As a Theranostic Nanoplatform against Cancer Cells

Although demanding, the development of multifunctional theranostic nanoplatforms is attracting considerable worldwide interest. Herein, a theranostic nanoplatform with multifunctions based on polydopamine (PDA) nanoparticles (NPs) was developed, owning dual-imaging and dual-therapy functions for cancer theranostic applications. PDA NPs were generated using a facile polymerization method under alkaline conditions, followed by poly(ethylene glycol) (PEG) modification. Then, the obtained NPs were loaded with IR820 and Fe³⁺ ions to produce the final PEGylated PDA/IR820/Fe³⁺ (PPIF) NPs. The PPIF NPs thus generated displayed increasingly brighter photoacoustic and magnetic resonance signals with increasing NP concentration and were demonstrated to be cytocompatible and effectively taken up and internalized into HeLa cells. Under near-infrared light irradiation, PPIF NPs can produce heat and reactive oxygen species for photothermal/photodynamic combined cancer therapy. In this study, the versatility of PDA NPs was demonstrated to be promising as a multifunctional nanoplatform for potential cancer theranostic applications.

Decorating gold nanostars with multiwalled carbon nanotubes for photothermal therapy

Gold nanoparticles and carbon nanotubes have attracted substantial attention in recent years for their potential applications in photothermal therapy (PTT) as an emerging breakthrough in cancer treatment. Herein, a hybrid nanomaterial of gold nanostars/multiwalled carbon nanotubes (MWCNTs) was synthesized by two-step reduction via the control of several synthetic conditions such as the reducing agent, pH value, concentration and ratio of reagents. The material shows good biocompatibility and high photothermal conversion efficiency, demonstrating its applicability in PTT. The lack of surfactant in the synthesis process made the hybrid nanomaterial cell-friendly, with no effects on viability in vitro. The MWCNT/gold nanostars hybrid nanomaterial presented 12.4% higher photothermal efficiency than gold nanostars alone and showed a 2.4-fold increase over gold nanospheres based on a heating test under 808 nm laser irradiation. Moreover, the MWCNTs/gold nanostars at low concentration (0.32 nM) exhibited remarkably improved photothermal cancer cell-killing efficacy, which may be attributed to the surface plasmon resonance absorption of the gold nanostars and the combined effects of enhanced coupling between the MWCNTs and gold nanostars. Collectively, these results demonstrate that the MWCNTs/gold nanostars developed herein show prominent photothermal value, and thus may serve as a novel photothermal agent for cancer therapy.

Dual pH/reduction-responsive hybrid polymeric micelles for targeted chemo-photothermal combination therapy

The combination of chemotherapy and photothermal therapy in multifunctional nanovesicles has emerged as a promising strategy to improve cancer therapeutic efficacy. Herein, we designed new pH/reduction dual-responsive and folate decorated polymeric micelles (FA Co-PMs) as theranostic nanocarrier to co-encapsulate doxorubicin (DOX) and indocyanine green (ICG) for targeted NIR imaging and chemo-photothermal combination therapy. The Co-PMs exhibited nano-sized structure (∼100 nm) with good monodispersity, high encapsulation efficiency of both ICG and DOX, triggered DOX release in response to acid pH and reduction environment, and excellent temperature conversion with laser irradiation. In vitro cellular uptake study indicated FA Co-PMs achieved significant targeting to BEL-7404 cells via folate receptor-mediated endocytosis, and laser-induced hyperthermia further enhanced drug accumulation into cancer cells. In vivo biodistribution study indicated that FA Co-PMs prolonged drug circulation and enhanced drug accumulation into the tumor via EPR effect and FA targeting. Furthermore, the ICG-based photo-triggered hyperthermia combined with DOX-based chemotherapy synergistically induced the BEL-7404 cell death and apoptosis, and efficiently suppressed the BEL-7404 xenografted tumor growth while significantly reduced systemic toxicity in vivo. Therefore, the designed dual-responsive Co-PMs were promising theranostic nanocarriers for versatile antitumor drug delivery and imaging-guided cancer chemo-photothermal combination therapy.

STATEMENT OF SIGNIFICANCE

The combination of chemotherapy and photothermal therapy in multifunctional nanovesicles has emerged as a promising strategy to improve cancer therapeutic efficacy. Herein, we designed novel pH/reduction dual-responsive and folate decorated polymeric micelles (FA Co-PMs) as theranostic nanocarrier to co-encapsulate doxorubicin (DOX) and indocyanine green (ICG) for targeted NIR imaging and chemo-photothermal combination therapy. The Co-PMs triggered DOX release in response to acid pH and reduction environment and exhibited excellent temperature conversion with laser irradiation. The results indicated FA Co-PMs achieved significant targeting to BEL-7404 cells in vitro and efficiently suppressed the BEL-7404 xenografted tumor growth while significantly reduced systemic toxicity in vivo. Therefore, the designed dual-responsive Co-PMs displayed great potential in imaging-guided cancer chemo-photothermal combination therapy as theranostic nanocarriers.

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

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

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.

Dual target gene therapy to EML4-ALK NSCLC by a gold nanoshell-based system

Although EML4-ALK transforming fusion gene is represented in only 8% of non-small cell lung cancer (NSCLC) cases, its expression is partly responsive for the failure of current NSCLC treatments. Preventing secondary mutation of the ALK protein through direct gene manipulation could overcome NSCLC drug resistance. Method: In this study, we developed a gold nanoshell (HAuNs) drug carrier for delivery and selective photo-thermal release of genes that target ALK and microRNA-301 in NSCLC. Additionally, the densely-coated nanoshell adsorbed high amounts of the positively-charged anticancer drug doxorubicin (DOX), generating an exciting multidimensional treatment strategy that includes gene-, thermal- and chemo- therapy. Results: The ALK mRNA and microRNA-301 genes as the double targets exhibited the combined effect. The drug carrier system significantly improved the drug accumulation in tumor tissues due to the enhanced vascular permeability by photothermal effect, dense spherical structure and RGD peptide modification. In vitro and in vivo results demonstrated the multiple therapeutic effects of the gold nanoshell-based system was better than the monotherapy. Conclusion: The above results indicated the gold nanoshell-based system would be a promising translational nano-formulation platform for effective treatment of EML4-ALK-positive NSCLC.

The synthesis of core–shell Cu9S5@mSiO2–ICG@PEG–LA for photothermal and photodynamic therapy

A Cu₉S₅@mSiO₂–ICG@PEG–LA core–shell nanocomposite was synthesized to integrate NIR-modulated PTT and PDT, revealing enhanced cytotoxicity to the HepG2 cell.