Loco-regional treatment with temozolomide-loaded thermogels prevents glioblastoma recurrences in orthotopic human xenograft models.

Glioblastoma multiforme (GBM) is the most aggressive primary tumor of the central nervous system and the diagnosis is often dismal. GBM pharmacological treatment is strongly limited by its intracranial location beyond the blood-brain barrier (BBB). While Temozolomide (TMZ) exhibits the best clinical performance, still less than 20% crosses the BBB, therefore requiring administration of very high doses with resulting unnecessary systemic side effects. Here, we aimed at designing new negative temperature-responsive gel formulations able to locally release TMZ beyond the BBB. The biocompatibility of a chitosan-ß-glycerophosphate-based thermogel (THG)-containing mesoporous SiO2 nanoparticles (THG@SiO2) or polycaprolactone microparticles (THG@PCL) was ascertained in vitro and in vivo by cell counting and histological examination. Next, we loaded TMZ into such matrices (THG@SiO2-TMZ and THG@PCL-TMZ) and tested their therapeutic potential both in vitro and in vivo, in a glioblastoma resection and recurrence mouse model based on orthotopic growth of human cancer cells. The two newly designed anticancer formulations, consisting in TMZ-silica (SiO2@TMZ) dispersed in the thermogel matrix (THG@SiO2-TMZ) and TMZ, spray-dried on PLC and incorporated into the thermogel (THG@PCL-TMZ), induced cell death in vitro. When applied intracranially to a resected U87-MG-Red-FLuc human GBM model, THG@SiO2-TMZ and THG@PCL-TMZ caused a significant reduction in the growth of tumor recurrences, when compared to untreated controls. THG@SiO2-TMZ and THG@PCL-TMZ are therefore new promising gel-based local therapy candidates for the treatment of GBM.

Overcoming challenges in glioblastoma treatment: targeting infiltrating cancer cells and harnessing the tumor microenvironment.

Glioblastoma (GB) is a highly malignant primary brain tumor with limited treatment options and poor prognosis. Despite current treatment approaches, including surgical resection, radiation therapy, and chemotherapy with temozolomide (TMZ), GB remains mostly incurable due to its invasive growth pattern, limited drug penetration beyond the blood-brain barrier (BBB), and resistance to conventional therapies. One of the main challenges in GB treatment is effectively eliminating infiltrating cancer cells that remain in the brain parenchyma after primary tumor resection. We've reviewed the most recent challenges and surveyed the potential strategies aimed at enhancing local treatment outcomes.

Erythro-Magneto-HA-Virosome: A Bio-Inspired Drug Delivery System for Active Targeting of Drugs in the Lungs.

Over the past few decades, finding more efficient and selective administration routes has gained significant attention due to its crucial role in the bioavailability, absorption rate and pharmacokinetics of therapeutic substances. The pulmonary delivery of drugs has become an attractive target of scientific and biomedical interest in the health care research area, as the lung, thanks to its high permeability and large absorptive surface area and good blood supply, is capable of absorbing pharmaceuticals either for local deposition or for systemic delivery. Nevertheless, the pulmonary drug delivery is relatively complex, and strategies to mitigate the effects of mechanical, chemical and immunological barriers are required. Herein, engineered erythrocytes, the Erythro-Magneto-Hemagglutinin (HA)-virosomes (EMHVs), are used as a novel strategy for efficiently delivering drugs to the lungs. EMHV bio-based carriers exploit the physical properties of magnetic nanoparticles to achieve effective targeting after their intravenous injection thanks to an external magnetic field. In addition, the presence of hemagglutinin fusion proteins on EMHVs' membrane allows the DDS to anchor and fuse with the target tissue and locally release the therapeutic compound. Our results on the biomechanical and biophysical properties of EMHVs, such as the membrane robustness and deformability and the high magnetic susceptibility, as well as their in vivo biodistribution, highlight that this bio-inspired DDS is a promising platform for the controlled and lung-targeting delivery of drugs, and represents a valuable alternative to inhalation therapy to fulfill unmet clinical needs.

Silencing Survivin: a Key Therapeutic Strategy for Cardiac Hypertrophy.

Cardiac hypertrophy, in its aspects of localized thickening of the interventricular septum and concentric increase of the left ventricle, constitutes a risk factor of heart failure. Myocardial hypertrophy, in the presence of different degree of myocardial fibrosis, is paralleled by significant molecular, cellular, and histological changes inducing alteration of cardiac extracellular matrix composition as well as sarcomeres and cytoskeleton remodeling. Previous studies indicate osteopontin (OPN) and more recently survivin (SURV) overexpression as the hallmarks of heart failure although SURV function in the heart is not completely clarified. In this study, we investigated the involvement of SURV in intracellular signaling of hypertrophic cardiomyocytes and the impact of its transcriptional silencing, laying the foundation for novel target gene therapy in cardiac hypertrophy. Oligonucleotide-based molecules, like theranostic optical nanosensors (molecular beacons) and siRNAs, targeting SURV and OPN mRNAs, were developed. Their diagnostic and therapeutic potential was evaluated in vitro in hypertrophic FGF23-induced human cardiomyocytes and in vivo in transverse aortic constriction hypertrophic mouse model. Engineered erythrocyte was used as shuttle to selectively target and transfer siRNA molecules into unhealthy cardiac cells in vivo. The results highlight how the SURV knockdown could negatively influence the expression of genes involved in myocardial fibrosis in vitro and restores structural, functional, and morphometric features in vivo. Together, these data suggested that SURV is a key factor in inducing cardiomyocytes hypertrophy, and its shutdown is crucial in slowing disease progression as well as reversing cardiac hypertrophy. In the perspective, targeted delivery of siRNAs through engineered erythrocytes can represent a promising therapeutic strategy to treat cardiac hypertrophy. Theranostic SURV molecular beacon (MB-SURV), transfected into FGF23-induced hypertrophic human cardiomyocytes, significantly dampened SURV overexpression. SURV down-regulation determines the tuning down of MMP9, TIMP1 and TIMP4 extracellular matrix remodeling factors while induces the overexpression of the cardioprotective MCAD factor, which counterbalance the absence of pro-survival and anti-apoptotic SURV activity to protect cardiomyocytes from death. In transverse aortic constriction (TAC) mouse model, the SURV silencing restores the LV mass levels to values not different from the sham group and counteracts the progressive decline of EF, maintaining its values always higher with respect to TAC group. These data demonstrate the central role of SURV in the cardiac reverse remodeling and its therapeutic potential to reverse cardiac hypertrophy.

The FHP01 DDX3X Helicase Inhibitor Exerts Potent Anti-Tumor Activity In Vivo in Breast Cancer Pre-Clinical Models.

Inhibition of DDX3X expression or activity reduces proliferation in cells from various tumor tissues, in particular in breast cancer, and its expression often correlates to tumor aggressiveness. This makes DDX3X a prominent candidate for the design of drugs for novel personalized therapeutic strategies. Starting from an in silico drug discovery approach, a group of molecules has been selected by molecular docking at the RNA binding site of DDX3X. Here, the most promising among them, FHP01, was evaluated in breast cancer preclinical models. Specifically, FHP01 exhibited very effective antiproliferative and killing activity against different breast cancer cell types, among which those from triple-negative breast cancer (TNBC). Interestingly, FHP01 also inhibited WNT signaling, a key tumorigenic pathway already correlated to DDX3X functions in breast cancer model cell lines. Ultimately, FHP01 also caused a significant reduction, in vivo, in the growth of MDA MB 231-derived TNBC xenograft models. Importantly, FHP01 showed good bioavailability and no toxicity on normal peripheral blood mononuclear cells in vitro and on several mouse tissues in vivo. Overall, our data suggest that the use of FHP01 and its related compounds may represent a novel therapeutic approach with high potential against breast cancer, including the triple-negative subtype usually correlated to the most unfavorable outcomes because of the lack of available targeted therapies.

Magnetically driven drug delivery systems improving targeted immunotherapy for colon-rectal cancer.

Colorectal cancer (CRC) is one of the major causes of cancer-associated mortality worldwide. The currently approved therapeutic agents show a rather limited efficacy. We have recently demonstrated that the atypical cadherin FAT1 is a specific marker of CRC and that the FAT1-specific monoclonal antibody mAb198.3 may offer new therapeutic opportunities for CRC, being efficiently internalized by cancer cells and reducing cancer growth in colon cancer xenograft models. In this study we explored the therapeutic efficacy of mAb198.3 using two drug delivery systems (DDS) for improving the targeted treatment of CRC. The mAb198.3 was either directly bound to super-paramagnetic nanoparticles (spmNPs) or embedded into human erythrocyte-based magnetized carriers, named Erythro-Magneto-Hemagglutinin Virosomes (EMHVs) to produce two different novel mAb198.3 formulations. Both DDS were endowed with magnetic properties and were anchored in the target tumor site by means of an external permanent magnet. The antibody loading efficiency of these two magnetically driven drug delivery systems and the overall therapeutic efficacy of these two formulations were assessed both in vitro and in a proof-of-concept in vivo study. We demonstrated that mAb198.3 bound to spmNPs or embedded into EMHVs was very effective in targeting FAT1-positive colon cancer cells in vitro and accumulating in the tumor mass in vivo. Although both in vivo administered mAb198.3 formulations have approximately 200 lower antibody doses needed, these showed to achieve a relevant therapeutic effect, thus reducing cancer growth more efficiently respect to the naked antibody. These results indicate that the two proposed magnetically driven drug delivery systems have a considerable potential as platforms to improve bioavailability and pharmacodynamics of anti-FAT mAb198.3 and raise new opportunities for a targeted therapy of CRC.

Focal Stroke in the Developing Rat Motor Cortex Induces Age- and Experience-Dependent Maladaptive Plasticity of Corticospinal System.

Motor system development is characterized by an activity-dependent competition between ipsilateral and contralateral corticospinal tracts (CST). Clinical evidence suggests that age is crucial for developmental stroke outcome, with early lesions inducing a "maladaptive" strengthening of ipsilateral projections from the healthy hemisphere and worse motor impairment. Here, we investigated in developing rats the relation between lesion timing, motor outcome and CST remodeling pattern. We induced a focal ischemia into forelimb motor cortex (fM1) at two distinct pre-weaning ages: P14 and P21. We compared long-term motor outcome with changes in axonal sprouting of contralesional CST at red nucleus and spinal cord level using anterograde tracing. We found that P14 stroke caused a more severe long-term motor impairment than at P21, and induced a strong and aberrant contralesional CST sprouting onto denervated spinal cord and red nucleus. The mistargeted sprouting of CST, and the worse motor outcome of the P14 stroke rats were reversed by an early skilled motor training, underscoring the potential of early activity-dependent plasticity in modulating lesion outcome. Thus, changes in the mechanisms controlling CST plasticity occurring during the third postnatal week are associated with age-dependent regulation of the motor outcome after stroke.

Targeting Cancer with Epi-Drugs: A Precision Medicine Perspective.

Recent pan-cancer studies have shown the importance of coupling DNA methylation patterns with transcriptome profiles to reveal tumor subgroups with clinically relevant distinct characteristics. While the coupling patterns remain in most cases matter for further study and/or interpretation, it is emerging that all associations between epigenetic changes and specific cancer histotypes can facilitate the development of novel epidrugs. In particular, together with chemotherapy and chemoprevention of cancer, these epidrugs will target specific enzymes involved in the complex regulation of gene expression. This perspective surveys recent cancer epigenetic findings on target drugs and therapeutic strategies, and focuses on the epigenetic modifications that can reverse a stable differentiated state of adult cell towards neoplastic phenotypes. The relevance of such developments may thus pave the way for patient's customized personalized therapies.

Magnetically driven nanoparticles: 18 FDG-radiolabelling and positron emission tomography biodistribution study.

Superparamagnetic iron oxide nanoparticles (SPIONs) have received increasing interest as contrast media in biomedical imaging and innovative therapeutic tools, in particular for loco-regional ablative treatments and drug delivery. The future of therapeutic applications would strongly benefit from improving the capability of the nanostructured constructs to reach the selected target, in particular beyond the intravascular space. Besides the decoration of SPIONs surface with ad hoc bioactive molecules, external magnetic fields are in principle able to remotely influence SPIONs' physiological biodistribution and concentrate them to a specific anatomical region or portion of a tissue. The reduction of SPIONs administered to the body and the need for defining the effective SPIONs local concentration suggest that PET/CT may be a method to quantitatively detect the nanoparticles accumulation in vivo at low concentration and assess their tridimensional distribution in response to an external magnetic field and in relation to the local anatomy highlighted by CT imaging. Here, we report on the possibility to assess the spatial distribution of magnetically-driven radiolabelled SPIONs in a peripheral tissue (mouse thigh) with microPET/CT imaging. To this aim we labelled SPIONs using 18 F-2-fluoro-2-deoxyglucose as a synthon, by chemoselective oxime formation between its open-chain tautomer and nanoparticle amino-groups, and employed microPET/CT imaging to measure the radiolabelled construct biodistribution in a small animal model, following intravenous administration, with and without the application of a permanent magnet onto the skin. The in vivo and ex vivo results showed that micro-PET/CT was able to demonstrate the localizing action of the magnet on SPIONs and provide information, in a multimodal 3D data set, about SPIONs biodistribution taking into account the local anatomy. Copyright © 2017 John Wiley & Sons, Ltd.

Perilesional treatment with chondroitinase ABC and motor training promote functional recovery after stroke in rats.

Ischemic stroke insults may lead to chronic functional limitations that adversely affect patient movements. Partial motor recovery is thought to be sustained by neuronal plasticity, particularly in areas close to the lesion site. It is still unknown if treatments acting exclusively on cortical plasticity of perilesional areas could result in behavioral amelioration. We tested whether enhancing plasticity in the ipsilesional cortex using local injections of chondroitinase ABC (ChABC) could promote recovery of skilled motor function in a focal cortical ischemia of forelimb motor cortex in rats. Using the skilled reaching test, we found that acute and delayed ChABC treatment induced recovery of impaired motor skills in treated rats. vGLUT1, vGLUT2, and vGAT staining indicated that functional recovery after acute ChABC treatment was associated with local plastic modification of the excitatory cortical circuitry positive for VGLUT2. ChABC effects on vGLUT2 staining were present only in rats undergoing behavioral training. Thus, the combination of treatments targeting the CSPG component of the extracellular matrix in perilesional areas and rehabilitation could be sufficient to enhance functional recovery from a focal stroke.

Novel epigenetic target therapy for prostate cancer: a preclinical study.

Epigenetic events are critical contributors to the pathogenesis of cancer, and targeting epigenetic mechanisms represents a novel strategy in anticancer therapy. Classic demethylating agents, such as 5-Aza-2'-deoxycytidine (Decitabine), hold the potential for reprograming somatic cancer cells demonstrating high therapeutic efficacy in haematological malignancies. On the other hand, epigenetic treatment of solid tumours often gives rise to undesired cytotoxic side effects. Appropriate delivery systems able to enrich Decitabine at the site of action and improve its bioavailability would reduce the incidence of toxicity on healthy tissues. In this work we provide preclinical evidences of a safe, versatile and efficient targeted epigenetic therapy to treat hormone sensitive (LNCap) and hormone refractory (DU145) prostate cancers. A novel Decitabine formulation, based on the use of engineered erythrocyte (Erythro-Magneto-Hemagglutinin Virosomes, EMHVs) drug delivery system (DDS) carrying this drug, has been refined. Inside the EMHVs, the drug was shielded from the environment and phosphorylated in its active form. The novel magnetic EMHV DDS, endowed with fusogenic protein, improved the stability of the carried drug and exhibited a high efficiency in confining its delivery at the site of action in vivo by applying an external static magnetic field. Here we show that Decitabine loaded into EMHVs induces a significant tumour mass reduction in prostate cancer xenograft models at a concentration, which is seven hundred times lower than the therapeutic dose, suggesting an improved pharmacokinetics/pharmacodynamics of drug. These results are relevant for and discussed in light of developing personalised autologous therapies and innovative clinical approach for the treatment of solid tumours.

Searching for the perfect wave: the effect of radiofrequency electromagnetic fields on cells.

There is a growing concern in the population about the effects that environmental exposure to any source of "uncontrolled" radiation may have on public health. Anxiety arises from the controversial knowledge about the effect of electromagnetic field (EMF) exposure to cells and organisms but most of all concerning the possible causal relation to human diseases. Here we reviewed those in vitro and in vivo and epidemiological works that gave a new insight about the effect of radio frequency (RF) exposure, relating to intracellular molecular pathways that lead to biological and functional outcomes. It appears that a thorough application of standardized protocols is the key to reliable data acquisition and interpretation that could contribute a clearer picture for scientists and lay public. Moreover, specific tuning of experimental and clinical RF exposure might lead to beneficial health effects.

Novel siRNA delivery strategy: a new "strand" in CNS translational medicine?

RNA interference has been envisaged as a powerful tool for molecular and clinical investigation with a great potential for clinical applications. In recent years, increased understanding of cancer biology and stem cell biology has dramatically accelerated the development of technology for cell and gene therapy in these areas. This paper is a review of the most recent report of innovative use of siRNA to benefit several central nervous system diseases. Furthermore, a description is made of innovative strategies of delivery into the brain by means of viral and non-viral vectors with high potential for translation into clinical use. Problems are also highlighted that might hamper the transition from bench to bed, analyzing the lack of reliable preclinical models with predictive validity and the lack of effective delivery systems, which are able to overcome biological barriers and specifically reach the brain site of action.

Functionalized carbon nanotubes in the brain: cellular internalization and neuroinflammatory responses.

The potential use of functionalized carbon nanotubes (f-CNTs) for drug and gene delivery to the central nervous system (CNS) and as neural substrates makes the understanding of their in vivo interactions with the neural tissue essential. The aim of this study was to investigate the interactions between chemically functionalized multi-walled carbon nanotubes (f-MWNTs) and the neural tissue following cortical stereotactic administration. Two different f-MWNT constructs were used in these studies: shortened (by oxidation) amino-functionalized MWNT (oxMWNT-NH3(+)) and amino-functionalized MWNT (MWNT-NH3(+)). Parenchymal distribution of the stereotactically injected f-MWNTs was assessed by histological examination. Both f-MWNT were uptaken by different types of neural tissue cells (microglia, astrocytes and neurons), however different patterns of cellular internalization were observed between the nanotubes. Furthermore, immunohistochemical staining for specific markers of glial cell activation (GFAP and CD11b) was performed and secretion of inflammatory cytokines was investigated using real-time PCR (qRT-PCR). Injections of both f-MWNT constructs led to a local and transient induction of inflammatory cytokines at early time points. Oxidation of nanotubes seemed to induce significant levels of GFAP and CD11b over-expression in areas peripheral to the f-MWNT injection site. These results highlight the importance of nanotube functionalization on their interaction with brain tissue that is deemed critical for the development nanotube-based vector systems for CNS applications.

In vivo distribution and toxicity of PAMAM dendrimers in the central nervous system depend on their surface chemistry.

Dendrimers have been described as one of the most tunable and therefore potentially applicable nanoparticles both for diagnostics and therapy. Recently, in order to realize drug delivery agents, most of the effort has been dedicated to the development of dendrimers that could internalize into the cells and target specific intracellular compartments in vitro and in vivo. Here, we describe cell internalization properties and diffusion of G4 and G4-C12 modified PAMAM dendrimers in primary neuronal cultures and in the CNS of live animals. Confocal imaging on primary neurons reveals that dendrimers are able to cross the cell membrane and reach intracellular localization following endocytosis. Moreover, functionalization of PAMAMs has a dramatic effect on their ability to diffuse in the CNS tissue in vivo and penetrate living neurons as shown by intraparenchymal or intraventricular injections. 100 nM G4-C12 PAMAM dendrimer already induces dramatic apoptotic cell death of neurons in vitro. On the contrary, G4 PAMAM does not induce apoptotic cell death of neural cells in the sub-micromolar range of concentration and induces low microglia activation in brain tissue after a week. Our detailed description of dendrimer distribution patterns in the CNS will facilitate the design of tailored nanomaterials in light of future clinical applications.

In vivo degradation of functionalized carbon nanotubes after stereotactic administration in the brain cortex.

AIM: Carbon nanotubes (CNTs) are increasingly being utilized in neurological applications as components of implants, electrodes or as delivery vehicles. Any application that involves implantation or injection of CNTs into the CNS needs to address the distribution and fate of the material following interaction and residence within the neuronal tissue. Here we report a preliminary study investigating the fate and structural integrity of amino-functionalized CNTs following stereotactic administration in the brain cortex. MATERIALS & METHODS: The CNTs investigated had previously shown the capacity to internalize in various cell types of the CNS. An aqueous suspension of multiwalled CNT-NH(3) (+) was stereotactically injected into the mouse brain cortex. Their interaction with neural cells and consequent effects on the CNT structural integrity was investigated by optical, transmission electron microscopy and Raman spectroscopy of brain tissue sections for a period between 2 and 14 days post cortical administration. RESULTS & DISCUSSION: The occurrence of severe nanotube structure deformation leading to partial degradation of the chemically functionalized-multiwalled CNT-NH(3) (+) in vivo following internalization within microglia was revealed even at early time points. Such initial observations of CNT degradation within the brain tissue render further systematic investigations using high-resolution tools imperative.

Carbon nanotube-mediated wireless cell permeabilization: drug and gene uptake.

AIM: This work aims to exploit the 'antenna' properties of multiwalled carbon nanotubes (MWCNTs). They can be used to induce cell permeabilization in order to transfer drugs (normally impermeable to cell membranes) both in in vitro and in vivo models. MATERIAL & METHODS: The performance of the MWCNTs as receiver antenna was modeled by finite element modeling. Once the appropriate field has been identified, the antenna properties of MWCNTs were investigated in sequential experiments involving immortalized fibroblast cell line (drug model: doxorubicin chemotherapeutic agent) and living mice (drug model: bcl-2 antiapoptotic gene) following stereotactic injection in the cerebral motor cortex. RESULTS: Finite element modeling analysis predicts that our MWCNTs irradiated in the radiofrequency field resemble thin-wire dipole antennas. In vitro experiments confirmed that combination of MWCNTs and electromagnetic field treatment dramatically favors intracellular drug uptake and, most importantly, drug nuclear localization. Finally, the brain of each irradiated animal exhibits a significantly higher number of transfected cells compared with the appropriate controls. CONCLUSION: This wireless application has the potential for MWCNT-based intracellular drug delivery and electro-stimulation therapies.

Increased susceptibility to cortical spreading depression in the mouse model of familial hemiplegic migraine type 2.

Familial hemiplegic migraine type 2 (FHM2) is an autosomal dominant form of migraine with aura that is caused by mutations of the α2-subunit of the Na,K-ATPase, an isoform almost exclusively expressed in astrocytes in the adult brain. We generated the first FHM2 knock-in mouse model carrying the human W887R mutation in the Atp1a2 orthologous gene. Homozygous Atp1a2(R887/R887) mutants died just after birth, while heterozygous Atp1a2(+/R887) mice showed no apparent clinical phenotype. The mutant α2 Na,K-ATPase protein was barely detectable in the brain of homozygous mutants and strongly reduced in the brain of heterozygous mutants, likely as a consequence of endoplasmic reticulum retention and subsequent proteasomal degradation, as we demonstrate in transfected cells. In vivo analysis of cortical spreading depression (CSD), the phenomenon underlying migraine aura, revealed a decreased induction threshold and an increased velocity of propagation in the heterozygous FHM2 mouse. Since several lines of evidence involve a specific role of the glial α2 Na,K pump in active reuptake of glutamate from the synaptic cleft, we hypothesize that CSD facilitation in the FHM2 mouse model is sustained by inefficient glutamate clearance by astrocytes and consequent increased cortical excitatory neurotransmission. The demonstration that FHM2 and FHM1 mutations share the ability to facilitate induction and propagation of CSD in mouse models further support the role of CSD as a key migraine trigger.

Functional motor recovery from brain ischemic insult by carbon nanotube-mediated siRNA silencing.

Stroke is the second cause of death worldwide with ischemic stroke accounting for 80% of all stroke insults. Caspase-3 activation contributes to brain tissue loss and downstream biochemical events that lead to programmed cell death after traumatic brain injury. Alleviation of symptoms following ischemic neuronal injury can be potentially achieved by either genetic disruption or pharmacological inhibition of caspases. Here, we studied whether silencing of Caspase-3 using carbon nanotube-mediated in vivo RNA interference (RNAi) could offer a therapeutic opportunity against stroke. Effective delivery of siRNA directly to the CNS has been shown to normalize phenotypes in animal models of several neurological diseases. It is shown here that peri-lesional stereotactic administration of a Caspase-3 siRNA (siCas 3) delivered by functionalized carbon nanotubes (f-CNT) reduced neurodegeneration and promoted functional preservation before and after focal ischemic damage of the rodent motor cortex using an endothelin-1 induced stroke model. These observations illustrate the opportunity offered by carbon nanotube-mediated siRNA delivery and gene silencing of neuronal tissue applicable to a variety of different neuropathological conditions where intervention at well localized brain foci may offer therapeutic and functional benefits.

The biocompatibility of amino functionalized CdSe/ZnS quantum-dot-Doped SiO2 nanoparticles with primary neural cells and their gene carrying performance.

Nanoparticles have an enormous potential for the development of applications in biomedicine such as gene or drug delivery. We developed and characterized NH(2) functionalized CdSe/ZnS quantum dot (QD)-doped SiO(2) nanoparticles (NPs) with both imaging and gene carrier capabilities. We show that QD-doped SiO(2) NPs are internalized by primary cortical neural cells without inducing cell death in vitro and in vivo. Moreover, the ability to bind, transport and release DNA into the cell allows GFP-plasmid transfection of NIH-3T3 and human neuroblastoma SH-SY5Y cell lines. QD-doped SiO(2) NPs properties make them a valuable tool for future nanomedicine application.