tellurium and Glioma

As the early detection and total destruction of gliomas are essential for longer survival, we attempted to synthesize a quantum dot (QD) that is capable of recognizing glioma cells for imaging and photodynamic therapy.. Using a one-pot aqueous approach, near infrared-emitting CdTe was produced. After detection of its physicochemical characteriistics, it was conjugated with RGD. The emission images were observed with confocal microscopy. To test its toxicity, CdTe-RGD at various concentrations was separately added to a human glioma cell line (U251) and a mouse embryo fibroblast cell line (3T3) (control) for incubation in dark conditions. To test its photodynamic effect, the U251 and 3T3 cells were then irradiated for 5-60 min, using a 632.8-nm laser.. This QD (Φ = 3.75 nm, photoluminescence (PL) peak wavelength = 700 nm, photoluminescence quantum yield (PLQY) = 20 %), was a spherical crystal with excellent monodispersity. Under a confocal microscope, U251 cells were visualized, but not the 3T3 cells. In dark conditions, the survival rates of both U251 and 3T3 cells were above 85 %. After laser irradiation, the survival rate of U251 cells decreased to 37 ± 1.6 % as the irradiation time and the CdTe-RGD concentration were increased.. With good physicochemical characteriistics and low toxicity, this QD-RGD has broad prospects for use in the biomedical imaging and photodynamic therapy of gliomas.

Topics: 3T3 Cells; Animals; Antineoplastic Agents; Brain Neoplasms; Cadmium Compounds; Cell Line, Tumor; Cell Survival; Glioblastoma; Glioma; Humans; In Vitro Techniques; Low-Level Light Therapy; Mice; Microscopy, Confocal; Oligopeptides; Photochemotherapy; Quantum Dots; Tellurium

The purpose of this study was to test the efficacy of cyclic Arg-Gly-Asp (RGD) peptide conjugated with polyionic complex nanomicelles as targeted therapy for glioma.. A stable cyclic RGD polyionic complex nanostructure, ie, a c(RGDfC) polyionic complex micelle, was synthesized and its biocompatibility with cultured neurons was assessed using a cell viability assay. Targeted binding to cultured glioma cells was evaluated by the CdTe quantum dot marking technique and a cell viability assay. The inhibitory effect of the nanomicelles against glioma cells was also evaluated, and their targeted migration into rat brain glioma cells and apoptotic effects were traced by the CdTe quantum dot marking and immunohistochemical staining.. c(RGDfC) polyionic complex micelles did not affect the growth of neurons but bonded selectively to and inhibited proliferation of glioma cells in vitro. When tested in vivo, the micelles migrated into glioma cells, inducing apoptosis in the rat brain.. The c(RGDfC) polyionic complex micelle is an effective targeted therapy against glioma.

Topics: Analysis of Variance; Animals; Antineoplastic Agents; Apoptosis; Brain Neoplasms; Cadmium Compounds; Cell Proliferation; Cell Survival; Cells, Cultured; Dose-Response Relationship, Drug; Drug Delivery Systems; Glioma; Hydrogen-Ion Concentration; Immunohistochemistry; Materials Testing; Micelles; Neurons; Oligopeptides; Quantum Dots; Rats; Rats, Wistar; Tellurium; Xenograft Model Antitumor Assays

We present and discuss results and features related to the synthesis of water-soluble semiconductor quantum dots and their application as fluorescent biomarkers in cancer diagnostics. We have prepared and applied different core-shell quantum dots, such as cadmium telluride-cadmium sulfide, CdTe-CdS, and cadmium sulfide-cadmium hydroxide, CdS/Cd(OH)(2), in living healthy and neoplastic cells and tissues samples. The CdS/Cd(OH)(2) quantum dots presented the best results, maintaining high levels of luminescence as well as high photostability in cells and tissues. Labeled tissues and cells were analyzed by their resulting fluorescence, via conventional fluorescence microscopy or via laser scanning confocal microscopy. The procedure presented in this work was shown to be efficient as a potential tool for fast and precise cancer diagnostics.

Topics: Cadmium Compounds; Cell Line, Tumor; Cells, Cultured; Cervix Uteri; Female; Fluorescence; Glioma; Humans; Microscopy, Confocal; Microscopy, Fluorescence; Nanotechnology; Neoplasms; Neuroglia; Quantum Dots; Sulfides; Tellurium; Uterine Cervical Dysplasia