Animal Research Facility

Washington, DC, United States

Animal Research Facility

Washington, DC, United States
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Di Paolo D.,Experimental Therapy Unit | Brignole C.,Experimental Therapy Unit | Pastorino F.,Experimental Therapy Unit | Carosio R.,Experimental Therapy Unit | And 11 more authors.
Molecular Therapy | Year: 2011

RNA interference molecules have some advantages as cancer therapeutics, including a proved efficacy on both wild-type (WT) and mutated transcripts and an extremely high sequence-specificity. The most significant hurdle to be overcome if exogenous small interfering RNAs (siRNA) is to be used therapeutically is the specific, effective, nontoxic delivery of siRNA to its intracellular site of action. At present, human applications are confined almost exclusively to targets within the liver, where the delivery systems naturally accumulate, and extra-hepatic targets remain a challenge. Anaplastic lymphoma kinase (ALK) is a receptor tyrosine kinase that has recently been shown to contribute to the cell growth and progression of human neuroblastoma (NB). We investigated its potential as a therapeutic target in NB by generating anti-GD 2-targeted nanoparticles that carry ALK-directed siRNA, which are specifically and efficiently delivered to GD 2-expressing NB cells. Relative to free ALK-siRNA, anti-GD 2-targeted liposomal formulations of ALK-siRNA had low plasma clearance, increased siRNA stability, and improved binding, uptake, silencing and induction of cell death, and specificity for NB cells. In NB xenografts, intravenous (i.v.) injection of the targeted ALK-siRNA liposomes showed gene-specific antitumor activity with no side effects. ALK-selective siRNA entrapped in anti-GD 2-targeted nanoparticles is a promising new modality for NB treatment. © The American Society of Gene &Cell Therapy.


Di Paolo D.,Experimental Therapy Unit | Ambrogio C.,University of Turin | Pastorino F.,Experimental Therapy Unit | Brignole C.,Experimental Therapy Unit | And 11 more authors.
Molecular Therapy | Year: 2011

The anaplastic lymphoma kinase (ALK) is a tyrosine kinase receptor that is involved in the pathogenesis of different types of human cancers, including neuroblastoma (NB). In NB, ALK overexpression, or point mutations, are associated with poor prognosis and advanced stage disease. Inhibition of ALK kinase activity by small-molecule inhibitors in lung cancers carrying ALK translocations has shown therapeutic potential. However, secondary mutations may occur that, generate tumor resistance to ALK inhibitors. To overcome resistance to ALK inhibitors in NB, we adopted an alternative RNA interference (RNAi)-based therapeutic strategy that is able to knockdown ALK, regardless of its genetic status mutated, amplified, wild-type (WT). NB cell lines, transduced by lentiviral short hairpin RNA (shRNA), showed reduced proliferation and increased apoptosis when ALK was knocked down. In mice, a nanodelivery system for ALK-specific small interfering RNA (siRNA), based on the conjugation of antibodies directed against the NB-selective marker GD 2 to liposomes, showed strong ALK knockdown in vivo in NB cells, which resulted in cell growth arrest, apoptosis, and prolonged survival. ALK knockdown was associated with marked reductions in vascular endothelial growth factor (VEGF) secretion, blood vessel density, and matrix metalloproteinases (MMPs) expression in vivo, suggesting a role for ALK in NB-induced neoangiogenesis and tumor invasion, confirming this gene as a fundamental oncogene in NB. © The American Society of Gene & Cell Therapy.


PubMed | Chemical Biology Group, The Surgical Center, Cancer Research Program, Regional Cancer Center and Animal Research Facility
Type: | Journal: Scientific reports | Year: 2016

Treatment outcome after surgical removal in oral carcinoma is poor due to inadequate methodologies available for marking surgical margins. Even though some methodologies for intraoperative margin assessment are under clinical and preclinical trials for other solid tumours, a promising modality for oral cancer surgery is not developed. Fluorescent-based optical imaging using Near Infrared (NIR) dyes tagged to tumour specific target will be an optimal tool for this purpose. One such target, Gastrin Releasing Peptide Receptor (GRPR) was selected for the study, and its binding peptide, TM1-IR680, was tested for its efficacy for surgical margin prediction in murine orthotopic model of oral cancer, derived from primary samples. Here, for the first time in a preclinical analysis, we show that the size and margin of oral cancer can be predicted, as revealed by 3D-imaging. Interestingly, the peptide was sensitive enough to detect lymph nodes that harboured dispersed tumour cells before colonization, which was impossible to identify by conventional histopathology. We recommend the use of TM1-NIR dyes alone or in combination with other technologies to improve the clinical outcome of oral cancer surgery.


Kornegay J.N.,Texas A&M University | Spurney C.F.,George Washington University | Nghiem P.P.,Animal Research Facility | Brinkmeyer-Langford C.L.,Texas A&M University | And 2 more authors.
ILAR Journal | Year: 2014

Duchenne muscular dystrophy (DMD) is an X-linked human disorder in which absence of the protein dystrophin causes degeneration of skeletal and cardiac muscle. For the sake of treatment development, over and above definitive genetic and cell-based therapies, there is considerable interest in drugs that target downstream disease mechanisms. Drug candidates have typically been chosen based on the nature of pathologic lesions and presumed underlying mechanisms and then tested in animalmodels. Mammalian dystrophinopathies have been characterized in mice (mdx mouse) and dogs (golden retriever muscular dystrophy [GRMD]). Despite promising results in the mdx mouse, some therapies have not shown efficacy in DMD. Although the GRMD model offers a higher hurdle for translation, dogs have primarily been used to test genetic and cellular therapies where there is greater risk. Failed translation of animal studies toDMD raises questions about the propriety of methods and models used to identify drug targets and test efficacy of pharmacologic intervention. The mdx mouse and GRMD dog are genetically homologous to DMD but not necessarily analogous. Subcellular species differences are undoubtedly magnified at the whole-body level in clinical trials. This problem is compounded by disparate cultures in clinical trials and preclinical studies, pointing to a need for greater rigor and transparency in animal experiments.Molecular assays such as mRNA arrays and genome-wide association studies allow identification of genetic drug targets more closely tied to disease pathogenesis. Genes in which polymorphisms have been directly linked to DMD disease progression, as with osteopontin, are particularly attractive targets. © The Author 2014. Published by Oxford University Press on behalf of the Institute for Laboratory Animal Research. All rights reserved.


Gs A.K.,Rajiv Gandhi Center for Biotechnology | Raj B.,Rajiv Gandhi Center for Biotechnology | Santhosh K.S.,Animal Research Facility | Sanjay G.,Sree Chitra Tirunal Institute for Medical Science and Technology | Kartha C.C.,Rajiv Gandhi Center for Biotechnology
Journal of visualized experiments : JoVE | Year: 2014

Ascending aortic constriction is the most common and successful surgical model for creating pressure overload induced cardiac hypertrophy and heart failure. Here, we describe a detailed surgical procedure for creating pressure overload and cardiac hypertrophy in rats by constriction of the ascending aorta using a small metallic clip. After anesthesia, the trachea is intubated by inserting a cannula through a half way incision made between two cartilage rings of trachea. Then a skin incision is made at the level of the second intercostal space on the left chest wall and muscle layers are cleared to locate the ascending portion of aorta. The ascending aorta is constricted to 50-60% of its original diameter by application of a small sized titanium clip. Following aortic constriction, the second and third ribs are approximated with prolene sutures. The tracheal cannula is removed once spontaneous breathing was re-established. The animal is allowed to recover on the heating pad by gradually lowering anesthesia. The intensity of pressure overload created by constriction of the ascending aorta is determined by recording the pressure gradient using trans-thoracic two dimensional Doppler-echocardiography. Overall this protocol is useful to study the remodeling events and contractile properties of the heart during the gradual onset and progression from compensated cardiac hypertrophy to heart failure stage.


PubMed | Sree Chitra Tirunal Institute for Medical Science and Technology, Rajiv Gandhi Center for Biotechnology and Animal Research Facility
Type: | Journal: Journal of visualized experiments : JoVE | Year: 2014

Ascending aortic constriction is the most common and successful surgical model for creating pressure overload induced cardiac hypertrophy and heart failure. Here, we describe a detailed surgical procedure for creating pressure overload and cardiac hypertrophy in rats by constriction of the ascending aorta using a small metallic clip. After anesthesia, the trachea is intubated by inserting a cannula through a half way incision made between two cartilage rings of trachea. Then a skin incision is made at the level of the second intercostal space on the left chest wall and muscle layers are cleared to locate the ascending portion of aorta. The ascending aorta is constricted to 50-60% of its original diameter by application of a small sized titanium clip. Following aortic constriction, the second and third ribs are approximated with prolene sutures. The tracheal cannula is removed once spontaneous breathing was re-established. The animal is allowed to recover on the heating pad by gradually lowering anesthesia. The intensity of pressure overload created by constriction of the ascending aorta is determined by recording the pressure gradient using trans-thoracic two dimensional Doppler-echocardiography. Overall this protocol is useful to study the remodeling events and contractile properties of the heart during the gradual onset and progression from compensated cardiac hypertrophy to heart failure stage.

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