NIR-Light-Triggered Anticancer Strategy for Dual-Modality Imaging-Guided Combination Therapy via a Bioinspired Hybrid PLGA Nanoplatform.

A promising approach toward cancer therapy is expected to integrate imaging and therapeutic agents into a versatile nanocarrier for achieving improved antitumor efficacy and reducing the side effects of conventional chemotherapy. Herein, we designed a poly(d,l-lactic- co-glycolic acid) (PLGA)-based theranostic nanoplatform using the double emulsion solvent evaporation method (W/O/W), which is associated with bovine serum albumin (BSA) modifications, to codeliver indocyanine green (ICG), a widely used near-infrared (NIR) dye, and doxorubicin (Dox), a chemotherapeutic drug, for dual-modality imaging-guided chemo-photothermal combination cancer therapy. The resultant ICG/Dox co-loaded hybrid PLGA nanoparticles (denoted as IDPNs) had a diameter of around 200 nm and exhibited excellent monodispersity, fluorescence/size stability, and biocompatibility. It was confirmed that IDPNs displayed a photothermal effect and that the heat induced faster release of Dox, which led to enhanced drug accumulation in cells and was followed by their efficient escape from the lysosomes into the cytoplasm and drug diffusion into the nucleus, resulting in a chemo-photothermal combinatorial therapeutic effect in vitro. Moreover, the IDPNs exhibited a high ability to accumulate in tumor tissue, owing to the enhanced permeability and retention (EPR) effect, and could realize real-time fluorescence/photoacoustic imaging of solid tumors with a high spatial resolution. In addition, the exposure of tumor regions to NIR irradiation could enhance the tumor penetration ability of IDPNs, almost eradicating subcutaneous tumors. In addition, the inhibition rate of IDPNs used in combination with laser irradiation against EMT-6 tumors in tumor-bearing nude mice (chemo-photothermal therapy) was approximately 95.6%, which was much higher than that for chemo- or photothermal treatment alone. Our study validated the fact that the use of well-defined IDPNs with NIR laser treatment could be a promising strategy for the early diagnosis and passive tumor-targeted chemo-photothermal therapy for cancer.

Endoscopic injection of human fibrin sealant in treatment of intrathoracic anastomotic leakage after esophageal cancer surgery.

OBJECTIVE: To investigate the application of endoscopic injection of human fibrin sealant in treatment of patients with intrathoracic anastomotic leakage after esophagectomy. METHODS: A total of 179 patients who underwent intrathoracic anastomosis after esophageal cancer surgery in our department From December 2012 to May 2015 were retrospectively analyzed. The clinical data and treatment of 7 patients with postoperative intrathoracic anastomotic leakage were analyzed and discussed. On Day 28 after operation, the 7 patients were given endoscopic injection of human fibrin sealant to seal the anastomotic leakage, and the changes in drainage volume, body temperature, CRP, white blood cell count and other indicators were compared before and after endoscopic intervention. RESULTS: After endoscopic injection of human fibrin sealant in all 7 patients with intrathoracic anastomotic leakage, the volume of para-anastomotic drainage, CRP, and WBC count were improved compared with those before treatment. Relevant data were analyzed, and the differences were statistically significant (P = 0.019, P = 0.001, P = 0.014, respectively). No statistically significant difference was observed in the body temperature before and after treatment (P = 0.217). CONCLUSION: For patients with intrathoracic anastomotic leakage after esophageal cancer surgery, endoscopic injection of human fibrin sealant to seal the anastomotic leakage has positive therapeutic effects of reducing exudation around the anastomotic leakage, reducing systemic inflammatory response, and improving clinical symptoms including dysphagia, weight loss without trying, chest pain, pressure or burning, worsening indigestion or heartburn and coughing or hoarseness.

Polymeric Hybrid Nanomicelles for Cancer Theranostics: An Efficient and Precise Anticancer Strategy for the Codelivery of Doxorubicin/miR-34a and Magnetic Resonance Imaging.

To realize precise tumor therapy, a versatile oncotherapy nanoplatform integrating both diagnostic and therapeutic functions is necessary. Herein, we fabricated a hybrid micelle (HM) utilizing two amphiphilic diblock copolymers, polyethylenimine-polycaprolactone (PEI-PCL) and diethylenetriaminepentaacetic acid gadolinium(III)  (Gd-DTPA)-conjugated polyethyleneglycol-polycaprolactone (Gd-PEG-PCL), to codeliver the small-molecule chemotherapy drugs doxorubicin (Dox) and microRNA-34a (miR-34a), denoted as Gd-HM-Dox/34a. Conjugating Gd-DTPA on the surface of hybrid micelles, leading the relaxation rate of Gd-DTPA increased more than 1.4 times (13.6 mM-1 S-1). Furthermore, hybrid micelles enhanced the ability of miR-34a to escape from lysosomes/endosomes and Dox release to the nucleus. In addition, the released miR-34a subsequently downregulates Bcl-2, cyclin D1, CDK6, and Bax expression and inhibits proliferation and migration of MDA-MB-231 breast cancer cells. Moreover, the suitable micelle size improved the penetration of Dox into three-dimensional (3D) multicellular spheroids compared with Gd-HM-Dox and Free Dox, generating efficient cell killing in the 3D multicellular spheroids. Furthermore, the Gd-HM-Dox/34a exhibited augmented accumulation in the tumor tissue, which improved the magnetic resonance (MR) imaging contrast of solid tumors and enhanced the combined efficiency of chemotherapeutic drugs Dox and therapeutic gene miR-34a in suppressing tumor growth on MDA-MB-231 tumor-bearing mice. Therefore, we established a hybrid micelle to offer a promising theranostic approach that inhibits tumor growth and enhances MR imaging.

Dendrimer-Functionalized Superparamagnetic Nanobeacons for Real-Time Detection and Depletion of HSP90α mRNA and MR Imaging.

Background & Aims: The use of antisense oligonucleotide-based nanosystems for the detection and regulation of tumor-related gene expression is thought to be a promising approach for cancer diagnostics and therapies. Herein, we report that a cubic-shaped iron oxide nanoparticle (IONC) core nanobeacon is capable of delivering an HSP90α mRNA-specific molecular beacon (HSP90-MB) into living cells and enhancing T2-weighted MR imaging in a tumor model. Methods: The nanobeacons were built with IONC, generation 4 poly(amidoamine) dendrimer (G4 PAMAM), Pluronic P123 (P123) and HSP90-MB labeled with a quencher (BHQ1) and a fluorophore (Alexa Fluor 488). Results: After internalization by malignant cells overexpressing HSP90α, the fluorescence of the nanobeacon was recovered, thus distinguishing cancer cells from normal cells. Meanwhile, MB-mRNA hybridization led to enzyme activity that degraded DNA/RNA hybrids and resulted in downregulation of HSP90α at both the mRNA and protein levels. Furthermore, the T2-weighted MR imaging ability of the nanobeacons was increased after PAMAM and P123 modification, which exhibited good biocompatibility and hemocompatibility. Conclusions: The nanobeacons show promise for applicability to tumor-related mRNA detection, regulation and multiscale imaging in the fields of cancer diagnostics and therapeutics.

Charge-reversal-functionalized PLGA nanobubbles as theranostic agents for ultrasonic-imaging-guided combination therapy.

The efficacy of cancer chemotherapy can be generally restrained by the multiple drug resistance (MDR) of tumors, which is typically attributed to the upregulation of ATP-binding cassette (ABC) transporter proteins, such as P-glycoprotein (P-gp). There is an urgent need to present innovative strategies to reverse MDR and enhance the therapeutic efficacy of chemotherapeutic agents in biomedical applications. Here, we report a novel nanosystem of charge-reversal-functionalized PLGA nanobubbles (denoted as Dox-NBs/PPP/P-gp shRNA) for the co-delivery of Dox and P-gp shRNA for the reversal of drug resistance and for ultrasonic-imaging-guided tumor therapy. 1H NMR, FT-IR, SEM, DLS, and UV-vis spectroscopy characterizations were conducted to determine the structure, morphology, and composition of the as-prepared nanobubbles. Dox-NBs/PPP/P-gp shRNA exhibited an average diameter of about 300 nm with good dispersity, biocompatibility, and pH-responsive release properties through the charge-reversal process. The in vitro experiments showed that Dox-NBs/PPP/P-gp shRNA nanobubbles could co-deliver Dox and P-gp shRNA into tumor cells and could effectively suppress P-gp expression, leading to enhanced overall therapeutic effects against MCF-7/MDR cells by restraining the drug efflux. An in vivo antitumor assay revealed an approximately 65% inhibition rate of Dox-NBs/PPP/P-gp shRNA against MCF-7/ADR tumors in tumor-bearing nude mice. Both the in vitro and in vivo toxicity results indicated the Dox-NBs/PPP/P-gp shRNA are highly biocompatible with reducing side-effects and have negligible systemic toxicity in the in vivo therapy of resistant cancers by combining with a chemotherapeutic agent and P-gp knockdown. Furthermore, the in vivo imaging data substantiated that the functionalized nanobubbles could be used as an efficient contrast agent for the ultrasonic imaging of solid tumors. This works highlights the great potential of Dox-NBs/PPP/P-gp shRNA nanobubbles for enhanced imaging-guided combination therapy for overcoming MDR.

Luminescent/magnetic PLGA-based hybrid nanocomposites: a smart nanocarrier system for targeted codelivery and dual-modality imaging in cancer theranostics.

Cancer diagnosis and treatment represent an urgent medical need given the rising cancer incidence over the past few decades. Cancer theranostics, namely, the combination of diagnostics and therapeutics within a single agent, are being developed using various anticancer drug-, siRNA-, or inorganic materials-loaded nanocarriers. Herein, we demonstrate a strategy of encapsulating quantum dots, superparamagnetic Fe3O4 nanocrystals, and doxorubicin (DOX) into biodegradable poly(d,l-lactic-co-glycolic acid) (PLGA) polymeric nanocomposites using the double emulsion solvent evaporation method, followed by coupling to the amine group of polyethyleneimine premodified with polyethylene glycol-folic acid (PEI-PEG-FA [PPF]) segments and adsorption of vascular endothelial growth factor (VEGF)-targeted small hairpin RNA (shRNA). VEGF is important for tumor growth, progression, and metastasis. These drug-loaded luminescent/magnetic PLGA-based hybrid nanocomposites (LDM-PLGA/PPF/VEGF shRNA) were fabricated for tumor-specific targeting, drug/gene delivery, and cancer imaging. The data showed that LDM-PLGA/PPF/VEGF shRNA nanocomposites can codeliver DOX and VEGF shRNA into tumor cells and effectively suppress VEGF expression, exhibiting remarkable synergistic antitumor effects both in vitro and in vivo. The cell viability was14% when treated with LDM-PLGA/PPF/VEGF shRNA nanocomposites ([DOX] =25 µg/mL), and in vivo tumor growth data showed that the tumor volume decreased by 81% compared with the saline group at 21 days postinjection. Magnetic resonance and fluorescence imaging data revealed that the luminescent/magnetic hybrid nanocomposites may also be used as an efficient nanoprobe for enhanced T2-weighted magnetic resonance and fluorescence imaging in vitro and in vivo. The present work validates the great potential of the developed multifunctional LDM-PLGA/PPF/VEGF shRNA nanocomposites as effective theranostic agents through the codelivery of drugs/genes and dual-modality imaging in cancer treatment.