Increased PDT Efficacy When Associated with Nitroglycerin: A Study on Retinoblastoma Xenografted on Mice.

Purposes: The aim of the study was to assess the efficacy of a treatment protocol that combines photodynamic therapy (PDT) and nitroglycerin (NG) on human retinoblastoma tumors xenografted on mice. We aimed to increase the PDT efficiency (in our least treatment-responsive retinoblastoma line) with better PS delivery to the tumor generated by NG, which is known to dilate vessels and enhance the permeability and retention of macromolecules in solid tumors.

Methods: In vivo follow-up of the therapeutic effects was performed by sodium MRI, which directly monitors variations in sodium concentrations non-invasively and can be used to track the tumor response to therapy.

AsiDNA Is a Radiosensitizer with no Added Toxicity in Medulloblastoma Pediatric Models.

Purpose: Medulloblastoma is an important cause of mortality and morbidity in pediatric oncology. Here, we investigated whether the DNA repair inhibitor, AsiDNA, could help address a significant unmet clinical need in medulloblastoma care, by improving radiotherapy efficacy without increasing radiation-associated toxicity.

Experimental Design: To evaluate the brain permeability of AsiDNA upon systemic delivery, we intraperitoneally injected a fluorescence form of AsiDNA in models harboring brain tumors and in models still in development.

Reverse-Contrast Imaging and Targeted Radiation Therapy of Advanced Pancreatic Cancer Models.

Purpose: To evaluate the feasibility of delivering experimental radiation therapy to tumors in the mouse pancreas. Imaging and treatment were performed using combined CT (computed tomography)/orthovoltage treatment with a rotating gantry.

Methods And Materials: After intraperitoneal administration of radiopaque iodinated contrast, abdominal organ delineation was performed by x-ray CT.

Cellular density, a major factor involved in PDT cytotoxic responses: Study on three different lines of human retinoblastoma grafted on nude mice.

Background: PDT represents a very localized and non-mutagen antitumoral treatment using a photosensitive molecule (porphyrin family) light activated. The first way of cell damage is a direct one, active on the very site where ROSs have been produced. The second one is indirect by activating and transmitting the processes of cellular death signaling.

Non-invasive mapping of deep-tissue lymph nodes in live animals using a multimodal PET/MRI nanoparticle.

The invasion status of tumour-draining lymph nodes (LNs) is a critical indicator of cancer stage and is important for treatment planning. Clinicians currently use planar scintigraphy and single-photon emission computed tomography (SPECT) with (99m)Tc-radiocolloid to guide biopsy and resection of LNs. However, emerging multimodality approaches such as positron emission tomography combined with magnetic resonance imaging (PET/MRI) detect sites of disease with higher sensitivity and accuracy.

Biobanking in a constantly developing medical world.

Biobank is a very sophisticated system that consists of a programmed storage of biological material and corresponding data. Biobanks are created to be used in medical research, in clinical and translational medicine, and in healthcare. In the past 20 years, a large number of biobanks have been set up around the world, to support the modern research directions in medicine such as omix and personalized medicine.

PDT induced bystander effect on human xenografted colorectal tumors as evidenced by sodium MRI.

Background: Previous in vivo studies on photodynamic therapy (PDT)-treated, high cellular density tumors showed evidences of a bystander effect accompanying the therapy, cellular death continuing beyond the limits of the photochemical reactions in time and space. This process is generated by the initially damaged cells on the light pathway. The aim of this study was to determine if the bystander effect may be induced as well in colorectal xenografted tumors (less compact structure) and if the cellular signaling depends primarily on cellular proximity or not.

Slc25a12 disruption alters myelination and neurofilaments: a model for a hypomyelination syndrome and childhood neurodevelopmental disorders.

Background: SLC25A12, a susceptibility gene for autism spectrum disorders that is mutated in a neurodevelopmental syndrome, encodes a mitochondrial aspartate-glutamate carrier (aspartate-glutamate carrier isoform 1 [AGC1]). AGC1 is an important component of the malate/aspartate shuttle, a crucial system supporting oxidative phosphorylation and adenosine triphosphate production.

Methods: We characterized mice with a disruption of the Slc25a12 gene, followed by confirmatory in vitro studies.

23Na MRI longitudinal follow-up of PDT in a xenograft model of human retinoblastoma.

Background: Photodynamic therapy is an established cancer treatment in which a photosensitizing agent is activated by exposure to light thus generating cytotoxic reactive oxygen species that cause cellular damage.

Methods: A new photosensitizer synthesized at Curie Institute was used to treat retinoblastoma xenografts in mice, a glycoconjugated meso substituted porphyrin derivative, that showed some retinoblastoma cell affinity. The longitudinal follow-up of the tumors was carried out by (23)Na MRI (without adding exogenous contrast agents) to map the extracellular compartment and to characterize cell packing.

Proton MRS detects metabolic changes in hormone sensitive and resistant human prostate cancer models CWR22 and CWR22r.

17-Allylamino, 17-demethoxygeldanamycin (17-AAG), an effective inhibitor of the heat shock protein hsp90, preferentially inhibiting tumor hsp90 compared to hsp90 from normal cells, has shown promising results against several cancers, including hormone-resistant prostate cancer. Levels of several oncogenic proteins critical to tumor growth and progression, such as androgen receptor and HER2/neu, were reduced 4 h post 17-allylamino, 17-demethoxygeldanamycin treatment. Posttreatment metabolic changes have also been observed in several tumor cell lines.

Atrasentan (ABT-627) enhances perfusion and reduces hypoxia in a human tumor xenograft model.

The endothelin-1 antagonist, Atrasentan (ABT-627) was used to modify perfusion in the human tumor xenograft model, HT29, growing in nude mice. Atrasentan produced a significant increase in perfusion, as measured in vivo by Gd-DTPA DCE-MRI. Changes in tumor hypoxia were assessed by comparing the binding of two hypoxia tracers, pimonidazole and EF5 given before and after Atrasentan administration.

Noninvasive multimodality imaging of the tumor microenvironment: registered dynamic magnetic resonance imaging and positron emission tomography studies of a preclinical tumor model of tumor hypoxia.

In vivo knowledge of the spatial distribution of viable, necrotic, and hypoxic areas can provide prognostic information about the risk of developing metastases and regional radiation sensitivity and may be used potentially for localized dose escalation in radiation treatment. In this study, multimodality in vivo magnetic resonance imaging (MRI) and positron emission tomography (PET) imaging using stereotactic fiduciary markers in the Dunning R3327-AT prostate tumor were performed, focusing on the relationship between dynamic contrast-enhanced (DCE) MRI using Magnevist (Gd-DTPA) and dynamic (18)F-fluoromisonidazole ((18)F-Fmiso) PET. The noninvasive measurements were verified using tumor tissue sections stained for hematoxylin/eosin and pimonidazole.

Simultaneous dynamic T1 and T2* measurement for AIF assessment combined with DCE MRI in a mouse tumor model.

A double-delay SR-MGE-SNAP sequence allowing simultaneous T1 and T2* measurement was developed for integrating arterial input function (AIF) measurement into DCE MRI. Implemented on a 4.7-T animal MR system, this technique was applied to mice with colorectal tumor xenografts.

Preclinical evaluation of tumor microvascular response to a novel antiangiogenic/antitumor agent RO0281501 by dynamic contrast-enhanced MRI at 1.5 T.

Inhibition of tumor angiogenesis is a promising approach in cancer treatment. The purpose of this study was to evaluate the vascular response of human lung tumor xenografts in vivo to RO0281501, an inhibitor of tyrosine kinase receptors, including vascular endothelial growth factor receptor 2, fibroblast growth factor receptor, and platelet-derived growth factor receptor, using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). Human non-small cell lung carcinoma (H460a) xenografts grown s.

Detection and quantitative analysis of early stage orthotopic murine bladder tumor using in vivo magnetic resonance imaging.

Purpose: We evaluated in vivo magnetic resonance imaging (MRI) as a noninvasive method for early detection and quantitative measurements of superficial tumors in an orthotopic murine bladder tumor model.

Materials And Methods: Murine bladder tumor cells were instilled into 25 mouse bladders and subsequently scanned with MRI 10, 14, 17 and 24 days after tumor inoculation. High quality T1-weighted spin-echo transverse images were obtained with 1.