Iodine nanoparticles enhance radiotherapy of intracerebral human glioma in mice and increase efficacy of chemotherapy.

Gliomas and other brain tumors have evaded durable therapies, ultimately causing about 20% of all cancer deaths. Tumors are widespread in the brain at time of diagnosis, limiting surgery and radiotherapy effectiveness. Drugs are also poorly effective.

Intravenously-injected gold nanoparticles (AuNPs) access intracerebral F98 rat gliomas better than AuNPs infused directly into the tumor site by convection enhanced delivery.

Background: Intravenously (IV)-injected gold nanoparticles (AuNPs) powerfully enhance the efficacy of X-ray therapy of tumors including advanced gliomas. However, pharmacokinetic issues, such as slow tissue clearance and skin discoloration, may impede clinical translation. The direct infusion of AuNPs into the tumor might be an alternative mode of delivery.

Gold nanoparticle hyperthermia reduces radiotherapy dose.

Unlabelled: Gold nanoparticles can absorb near infrared light, resulting in heating and ablation of tumors. Gold nanoparticles have also been used for enhancing the X-ray dose to tumors. The combination of hyperthermia and radiotherapy is synergistic, importantly allowing a reduction in X-ray dose with improved therapeutic results.

Infrared-transparent gold nanoparticles converted by tumors to infrared absorbers cure tumors in mice by photothermal therapy.

Gold nanoparticles (AuNPs) absorb light and can be used to heat and ablate tumors. The "tissue window" at ∼ 800 nm (near infrared, NIR) is optimal for best tissue penetration of light. Previously, large, 50-150 nm, gold nanoshells and nanorods that absorb well in the NIR have been used.

Microlocalization of lipophilic porphyrins: non-toxic enhancers of boron neutron-capture therapy.

Purpose: To compare the macroscopic and microscopic distributions of the novel non-toxic lipophilic porphyrins copper (II) 5,10,15,20-tetrakis-(3-[1,2 dicarba-closo-dodecaboranyl]methoxyphenyl)-porphyrin (CuTCPH), potentially useful for boron neutron-capture therapy (BNCT), with those of its zinc fluorescent congener zinc (II) 5,10,15,20-tetrakis-(3-[1,2 dicarba-closo-dodecaboranyl]methoxyphenyl)-porphyrin (ZnTCPH) in tissues of tumor-bearing mice.

Materials And Methods: ZnTCPH and CuTCPH were synthesized, then injected intraperitoneally (ip) into tumor-bearing mice. Macroscopic biodistribution was assessed by determining average boron concentrations in tumor, blood, brain, skin, and liver using atomic-emission spectrometry.

Response of the rat spinal cord to X-ray microbeams.

Background And Purpose: To quantify the late dose-related responses of the rat cervical spinal cord to X-ray irradiations by an array of microbeams or by a single millimeter beam.

Materials And Methods: Necks of anesthetized rats were irradiated transversely by an 11 mm wide array of 52 parallel, 35 μm wide, vertical X-ray microbeams, separated by 210 μm intervals between centers. Comparison was made with rats irradiated with a 1.

Gold nanoparticle imaging and radiotherapy of brain tumors in mice.

Aim: To test intravenously injected gold nanoparticles for x-ray imaging and radiotherapy enhancement of large, imminently lethal, intracerebral malignant gliomas.

Materials & Methods: Gold nanoparticles approximately 11 nm in size were injected intravenously and brains imaged using microcomputed tomography. A total of 15 h after an intravenous dose of 4 g Au/kg was administered, brains were irradiated with 30 Gy 100 kVp x-rays.

[Alban Köhler (1874-1947): Inventor of grid therapy].

Grid (or sieve) therapy ("Gitter-" oder "Siebtherapie"), spatially fractionated kilo- and megavolt X-ray therapy, was invented in 1909 by Alban Köhler, a radiologist in Wiesbaden, Germany. He tested it on several patients before 1913 using approximately 60-70kV Hittorf-Crookes tubes. Köhler pushed the X-ray tube's lead-shielded housing against a stiff grid of 1 mm-square iron wires woven 3.

Gold nanoparticles enhance the radiation therapy of a murine squamous cell carcinoma.

The purpose of this study is to test the hypothesis that gold nanoparticle (AuNP, nanogold)-enhanced radiation therapy (nanogold radiation therapy, NRT) is efficacious when treating the radiation resistant and highly aggressive mouse head and neck squamous cell carcinoma model, SCCVII, and to identify parameters influencing the efficacy of NRT. Subcutaneous (sc) SCCVII leg tumors in mice were irradiated with x-rays at the Brookhaven National Laboratory (BNL) National Synchrotron Light Source (NSLS) with and without prior intravenous (iv) administration of AuNPs. Variables studied included radiation dose, beam energy, temporal fractionation and hyperthermia.

Radiotherapy enhancement with gold nanoparticles.

Gold is an excellent absorber of X-rays. If tumours could be loaded with gold, this would lead to a higher dose to the cancerous tissue compared with the dose received by normal tissue during a radiotherapy treatment. Calculations indicate that this dose enhancement can be significant, even 200% or greater.

Tetrahedral irradiation protocol for microbeam radiation therapy.

Optimizing microbeam radiation therapy requires that the patient be repositioned between exposures. Optional movements of a patient-gantry are described that would enable a lesion to be cross-fired pseudo-orthogonally in two, three or four exposures to a fixed, horizontally propagated array of vertical, parallel microplanar beams, with minimal tilting of the patient-gantry.

The use of gold nanoparticles to enhance radiotherapy in mice.

Mice bearing subcutaneous EMT-6 mammary carcinomas received a single intravenous injection of 1.9 nm diameter gold particles (up to 2.7 g Au/kg body weight), which elevated concentrations of gold to 7 mg Au/g in tumours.

Uniaxial and biaxial irradiation protocols for microbeam radiation therapy.

Synchrotron-generated x-ray beams for microbeam radiation therapy (MRT) are fixed in space, so three-dimensional treatment planning would require that a patient be secured to, and moved in a gantry between exposures. Two protocols for such movements are proposed: one for uniaxial opposing-fields cross-planar MRT, the other for biaxial orthogonal-fields co-planar MRT.