silicon and Glioma

Approximately 80% of brain tumours are gliomas. Despite treatment, patient mortality remains high due to local metastasis and relapse. It has been shown that transferrin-functionalised porous silicon nanoparticles (Tf@pSiNPs) can inhibit the migration of U87 glioma cells. However, the underlying mechanisms and the effect of glioma cell heterogeneity, which is a hallmark of the disease, on the efficacy of Tf@pSiNPs remains to be addressed.. Here, we observed that Tf@pSiNPs inhibited heterogeneous patient-derived glioma cells' (WK1) migration across small perforations (3 μm) by approximately 30%. A phenotypical characterisation of the migrated subpopulations revealed that the majority of them were nestin and fibroblast growth factor receptor 1 positive, an indication of their cancer stem cell origin. The treatment did not inhibit cell migration across large perforations (8 μm), nor cytoskeleton formation. This is in agreement with our previous observations that cellular-volume regulation is a mediator of Tf@pSiNPs' cell migration inhibition. Since aquaporin 9 (AQP9) is closely linked to cellular-volume regulation, and is highly expressed in glioma, the effect of AQP9 expression on WK1 migration was investigated. We showed that WK1 migration is correlated to the differential expression patterns of AQP9. However, AQP9-silencing did not affect WK1 cell migration across perforations, nor the efficacy of cell migration inhibition mediated by Tf@pSiNPs, suggesting that AQP9 is not a mediator of the inhibition.. This in vitro investigation highlights the unique therapeutic potentials of Tf@pSiNPs against glioma cell migration and indicates further optimisations that are required to maximise its therapeutic efficacies.

Topics: Aquaporins; Brain Neoplasms; Cell Line, Tumor; Cell Movement; Glioblastoma; Glioma; Humans; Nanoparticles; Neoplastic Stem Cells; Porosity; Receptor, Fibroblast Growth Factor, Type 1; Silicon

Tumor angiogenesis is a complex process that is unamenable to intravital whole-process monitoring, especially on microscopic assessment of tumor microvessel and quantifying microvascular hemodynamics before and after the nanotherapeutics, which hinder the understanding of nanotheranostics outcomes in tumor treatment. Herein, a new photoacoustic (PA) imaging-optical coherence tomography angiography (OCTA)-laser speckle (LS) multimodal imaging strategy is first proposed, which is not only able to precisely macro guide the thermo-chemotherapy of tumor by monitoring blood oxygen saturation (SaO

Topics: Animals; Antimetabolites, Antineoplastic; Brain Neoplasms; Disease Models, Animal; Fluorouracil; Glioma; Humans; Male; Mice; Mice, Inbred BALB C; Multimodal Imaging; Nanostructures; Oxygen Saturation; Photoacoustic Techniques; Silicon; Tomography, Optical Coherence

The application of micro-Raman spectroscopy was used for characterization of structural features of the high-k stack (h-k) layer of "silicon-on-insulator" (SOI) nanowire (NW) chip (h-k-SOI-NW chip), including Al

Topics: Aged; Biosensing Techniques; Brain; Female; Glioma; Humans; Male; Middle Aged; Nanowires; Oligonucleotide Array Sequence Analysis; RNA, Circular; Silicon; Spectrum Analysis, Raman

Nanoribbon chips, based on "silicon-on-insulator" structures (SOI-NR chips), have been fabricated. These SOI-NR chips, whose surface was sensitized with covalently immobilized oligonucleotide molecular probes (oDNA probes), have been employed for the nanoribbon biosensor-based detection of a circular ribonucleic acid (circRNA) molecular marker of glioma in humans. The nucleotide sequence of the oDNA probes was complimentary to the sequence of the target oDNA. The latter represents a synthetic analogue of a glioma marker-NFIX circular RNA. In this way, the detection of target oDNA molecules in a pure buffer has been performed. The lowest concentration of the target biomolecules, detectable in our experiments, was of the order of ~10

Topics: Biosensing Techniques; Electronics; Glioma; Humans; MicroRNAs; Nanotubes, Carbon; Nanowires; Oligonucleotides; Silicon; Transistors, Electronic

Glioma is a common brain tumor with a high mortality rate. A small population of cells expressing stem-like cell markers in glioma contributes to drug resistance and tumor recurrence.. Porous silicon nanoparticles (PSi NPs) as photothermal therapy (PTT) agents loaded with TMZ (TMZ/PSi NPs), was combined with hyperbaric oxygen (HBO) therapy in vitro and in vivo. To further investigate underlying mechanism, we detected the expression of stem-like cell markers and hypoxia related molecules in vitro and in vivo after treatment of TMZ/PSi NPs in combination with PTT and HBO.. NCH-421K and C6 cells were more sensitive to the combination treatment. Moreover, the expression of stem-like cell markers and hypoxia related molecules were decreased after combination treatment. The in vivo results were in line with in vitro. The combination treatment presents significant antitumor effects in mice bearing C6 tumor compared with the treatment of TMZ, PTT or TMZ/PSi NPs only.. These results suggested the TMZ/PSi NPs combined with HBO and PTT could be a potential therapeutic strategy for glioma.

Topics: Animals; Antineoplastic Agents, Alkylating; Apoptosis; Brain Neoplasms; Cell Line, Tumor; Cell Proliferation; Cell Survival; Combined Modality Therapy; Glioma; Humans; Hyperbaric Oxygenation; Hyperthermia, Induced; Mice, Nude; Nanoparticles; Neoplasm Transplantation; Neoplastic Stem Cells; Particle Size; Porosity; Rats; Silicon; Temozolomide

To study the effects of combinational treatment of hyperbaric oxygen (HBO) and nanotemozolomide in glioma.. Temozolomide (TMZ)-loaded porous silicon nanoparticles (TMZ/PSi NPs) were prepared. In vitro and in vivo evaluations were performed.. The cell uptake of TMZ/PSi NPs could be tracked by autofluorescence of porous silicon. The concentration of oxygen in tumor was improved and the antitumor rate was increased to 84.2% in the TMZ/PSi NPs combined with HBO group. The viability of hypoxia-induced glioma C6 cells was decreased and cell cycle was arrested at G2/M phase in response to TMZ/PSi NPs treatment with HBO compared with continuous treatment with hypoxia.. The combinational treatment of TMZ/PSi NPs and HBO could be a promising therapeutic strategy for glioma.

Topics: Animals; Apoptosis; Cell Cycle Checkpoints; Cell Line, Tumor; Cell Proliferation; Cell Survival; G2 Phase Cell Cycle Checkpoints; Glioma; Humans; Hyperbaric Oxygenation; Mice; Nanoparticles; Oxygen; Radiation-Sensitizing Agents; Silicon; Temozolomide; Xenograft Model Antitumor Assays

Cell alignment plays an important role in the repair of damaged peripheral nerves. The aligned Schwann cells could direct the axonal outgrowth during nerve reconstruction. One way of aligning Schwann cells is to use surface grooves in micrometric dimensions. In this study, microgrooves on chitosan or poly(D,L-lactide) (PLA) were fabricated and the behaviors of Schwann cells and glial cell line C6 on these surfaces were examined. It was found that Schwann cells and C6 cells could be successfully aligned by the microgrooves, and express the genes related to the production of neurotrophic factors. The polymer conduits with microgrooves on the inner surface were implanted in rats to repair the damaged sciatic nerve. The microgrooved conduits were demonstrated to enhance peripheral nerve regeneration as compared to the smooth conduits.

Topics: Actins; Animals; Animals, Newborn; Biocompatible Materials; Biodegradation, Environmental; Brain-Derived Neurotrophic Factor; Cell Adhesion; Cell Culture Techniques; Cells, Cultured; Chitosan; Cytoskeleton; Dimethylpolysiloxanes; Feasibility Studies; Fluorescent Antibody Technique, Indirect; Gene Expression; Glioma; Lactic Acid; Male; Nerve Growth Factor; Peripheral Nerves; Polyesters; Polymers; Rats; Rats, Sprague-Dawley; S100 Proteins; Schwann Cells; Sciatic Nerve; Silicon; Time Factors; Vinculin

Control over the adsorption of proteins and over the adsorption and spatial orientation of mammalian cells onto surfaces has been achieved by modification of glass and other silicon oxide substrates with poly(N-isopropylacrylamide) (PNIPAM). The functionalization of the substrates was achieved either by a polymer-analogous reaction of aminosilanes with reactive N-(isopropylacrylamide) (NIPAM)-copolymers and by copolymerization of NIPAM with surface-bound methacrylsilane. The obtained coatings were characterized by FT-1R, ellipsometry, and surface plasmon resonance measurements. The adsorption of two proteins-fibrinogen and ribonuclease A-on these surfaces was studied in situ by real time surface plasmon resonance measurements. The PNIPAM-grafted surfaces prepared by either chemical procedure inhibited the adsorption of both proteins. More importantly they prevented the adhesion of neuroblastomaXglioma hybrid cells cultured either in serum-free medium or in a medium containing serum proteins. Deep-UV irradiation was used to perform ablation processes and to create patterns permitting the examination of spatially controlled adhesion and growth of cells. This study showed that patterned ultrathin polymer films on glass are suitable substrates for controlling the interactions of cells with surfaces and are capable of directing the attachment and spreading of cells.

Topics: Acrylamides; Biocompatible Materials; Blood Proteins; Cell Adhesion; Cell Division; Cell Survival; Glass; Glioma; Humans; Molecular Weight; Neuroblastoma; Oxidation-Reduction; Polymers; Silicon; Spectroscopy, Fourier Transform Infrared; Surface Properties; Tumor Cells, Cultured; Ultraviolet Rays