Lauryl-gemcitabine loaded nanomedicine hydrogel for the local treatment of glioblastoma

Glioblastoma (GBM) is one of the greatest challenges in oncology. The standard of care therapy of this highly malignant brain tumor includes surgical resection followed, one month after, by radiotherapy and chemotherapy with Temozolomide. However, GBM still remains incurable mainly because of its anatomical location, high intra - and inter-tumor heterogeneity and intrinsic characteristics that inevitably lead to the formation of recurrences [1]. Considering that 80-90% of GBM recurrences are localized in proximity of resection cavity borders we hypothesized to deliver an injectable nanomedicine hydrogel directly in the tumor resection cavity after surgery in order to obtain a sustained release of the drug. This could avoid the formation of recurrences before starting the conventional treatment. The hydrogel that we have developed and selected is formed of lipid nanocapsules (LNC) loaded with the prodrug Lauroyl -gemcitabine (GemC12), which shows excellent radio-sensitizing properties, could potentiate cancer immunotherapy and has a MGMT -independent mechanism of action [2,3]. This nanomedicine hydrogel is injectable, adapted for brain implantation and able to release the drug over one month in vitro [2]. In vivo, the anti-tumor efficacy studies in a subcutaneous and ortothopic GBM rodent models have shown, respectively, to decrease the tumor growth and increase the survival of the mice after intratumoral injection of the hydrogel compared to the controls. Also, to better mimic the clinical conditions, we have developed and validated a resection model of the GBM orthotopic tumor and on -going anti -tumor efficacy studies after administration of the treatment in the resection cavity are showing promising results. Moreover, short -, mid- and long- term tolerability studies (1 week, 2 months and 6 months) indicated that this system is well tolerated in the brain. In conclusion, we have demonstrated the fe asibility, safety and efficiency of the GemC12 -LNC hydrogel for the local treatment of GBM. This system, which has a very simple formulation and combines the properties and advantages of nanomedicines and hydrogels, could be considered as a promising platform for the delivery of GemC12 for the local treatment of GBM

Design and testing of hydrophobic core/hydrophilic shell nano/micro particles for drug-eluting stent coating

In this study, we designed a novel drug-eluting coating for vascular implants consisting of a core coating of the anti-proliferative drug docetaxel (DTX) and a shell coating of the platelet glycoprotein IIb/IIIa receptor monoclonal antibody SZ-21. The core/shell structure was sprayed onto the surface of 316L stainless steel stents using a coaxial electrospray process with the aim of creating a coating that exhibited a differential release of the two drugs. The prepared stents displayed a uniform coating consisting of nano/micro particles. In vitro drug release experiments were performed, and we demonstrated that a biphasic mathematical model was capable of capturing the data, indicating that the release of the two drugs conformed to a diffusion-controlled release system. We demonstrated that our coating was capable of inhibiting the adhesion and activation of platelets, as well as the proliferation and migration of smooth muscle cells (SMCs), indicating its good biocompatibility and anti-proliferation qualities. In an in vivo porcine coronary artery model, the SZ-21/DTX drug-loaded hydrophobic core/hydrophilic shell particle coating stents were observed to promote re-endothelialization and inhibit neointimal hyperplasia. This core/shell particle-coated stent may serve as part of a new strategy for the differential release of different functional drugs to sequentially target thrombosis and in-stent restenosis during the vascular repair process and ensure rapid re-endothelialization in the field of cardiovascular disease

Bioresponsive Mesoporous Silica Nanoparticles for Triggered Drug Release

Mesoporous silica nanoparticles (MSNPs) have garnered a great deal of attention as potential carriers for therapeutic payloads. However, achieving triggered drug release from MSNPs in vivo has been challenging. Here, we describe the synthesis of stimulus-responsive polymer-coated MSNPs and the loading of therapeutics into both the core and shell domains. We characterize MSNP drug-eluting properties in vitro and demonstrate that the polymer-coated MSNPs release doxorubicin in response to proteases present at a tumor site in vivo, resulting in cellular apoptosis. These results demonstrate the utility of polymer-coated nanoparticles in specifically delivering an antitumor payload.National Science Foundation (U.S.) (grant R01-CA124427)National Science Foundation (U.S.) (grant U54-CA119349)National Science Foundation (U.S.) (grant U54-CA119335

Targeting the Lactate Transporter MCT1 in Endothelial Cells Inhibits Lactate-Induced HIF-1 Activation and Tumor Angiogenesis

Switching to a glycolytic metabolism is a rapid adaptation of tumor cells to hypoxia. Although this metabolic conversion may primarily represent a rescue pathway to meet the bioenergetic and biosynthetic demands of proliferating tumor cells, it also creates a gradient of lactate that mirrors the gradient of oxygen in tumors. More than a metabolic waste, the lactate anion is known to participate to cancer aggressiveness, in part through activation of the hypoxia-inducible factor-1 (HIF-1) pathway in tumor cells. Whether lactate may also directly favor HIF-1 activation in endothelial cells (ECs) thereby offering a new druggable option to block angiogenesis is however an unanswered question. In this study, we therefore focused on the role in ECs of monocarboxylate transporter 1 (MCT1) that we previously identified to be the main facilitator of lactate uptake in cancer cells. We found that blockade of lactate influx into ECs led to inhibition of HIF-1-dependent angiogenesis. Our demonstration is based on the unprecedented characterization of lactate-induced HIF-1 activation in normoxic ECs and the consecutive increase in vascular endothelial growth factor receptor 2 (VEGFR2) and basic fibroblast growth factor (bFGF) expression. Furthermore, using a variety of functional assays including endothelial cell migration and tubulogenesis together with in vivo imaging of tumor angiogenesis through intravital microscopy and immunohistochemistry, we documented that MCT1 blockers could act as bona fide HIF-1 inhibitors leading to anti-angiogenic effects. Together with the previous demonstration of MCT1 being a key regulator of lactate exchange between tumor cells, the current study identifies MCT1 inhibition as a therapeutic modality combining antimetabolic and anti-angiogenic activities

Polymer functionalized nanocomposites for metals removal from water and wastewater: An overview

Pollution by metal and metalloid ions is one of the most widespread environmental concerns. They are non-biodegradable, and, generally, present high water solubility facilitating their environmental mobilisation interacting with abiotic and biotic components such as adsorption onto natural colloids or even accumulation by living organisms, thus, threatening human health and ecosystems. Therefore, there is a high demand for effective removal treatments of heavy metals, making the application of adsorption materials such as polymer-functionalized nanocomposites (PFNCs), increasingly attractive. PFNCs retain the inherent remarkable surface properties of nanoparticles, while the polymeric support materials provide high stability and processability. These nanoparticle-matrix materials are of great interest for metals and metalloids removal thanks to the functional groups of the polymeric matrixes that provide specific bindings to target pollutants. This review discusses PFNCs synthesis, characterization and performance in adsorption processes as well as the potential environmental risks and perspectives. (C) 2016 Elsevier Ltd. All rights reserved