CiteULike: xtizons mouse

Advances in imaging mouse tumour models in vivo

Scott Lyons — 2005-01-18T10:26:03-00:00

The Journal of Pathology, Vol. 205, No. 2. (January 2005), 194.

In vivo MRI volumetric measurement of prostate regression and growth in mice

Kent Nastiuk — 2007-07-25T05:50:00-00:00

BMC Urology, Vol. 7 (24 July 2007), 12.

Magnetic resonance imaging to measure therapeutic response using an orthotopic model of human pancreatic cancer.

Z He — 2007-06-01T12:58:58-00:00

Pancreas, Vol. 21, No. 1. (July 2000), pp. 69-76.

Pancreatic cancer is one of the most incurable and lethal human cancers in the United States. To facilitate development of novel therapeutic agents, we previously established an orthotopic pancreatic tumor model that closely mimics the natural biological behavior of human pancreatic cancer. In this study, magnetic resonance imaging (MRI) techniques were developed to detect tumor formation noninvasively and monitor serially tumor growth kinetics in this orthotopic model used for experimental drug testing. By using an optimized T2-weighted imaging method, we were able to distinguish human pancreas cancer from normal mouse pancreas. Orthotopic tumor formation was detected as early as day 1 after tumor cell implantation with a tumor volume as small as 12 mm3. Mice with evidence of tumor were separated into four treatment groups: control, auristatin-PE, gemcitabine, and their combination. After treatment, the mice were imaged at least three times before termination of the experiment. Comparison between MRI tumor volume measurements and tumor weights made at biopsy resulted in a correlation coefficient of 0.98. The tumor growth curves constructed from serial magnetic resonance imaging (MRI) measurements clearly showed tumor growth inhibition in treated mice compared with the control group. As expected, the group treated with the combination had the highest response rate compared with either auristatin-PE or gemcitabine alone, and the data were statistically highly significant (p < 0.004). From these results, we conclude that noninvasive MRI can be used to monitor serially therapeutic response in this orthotopic human pancreatic tumor model and can be used in the future to evaluate novel antitumor agents before human studies.

Noninvasive imaging of pancreatic inflammation and its reversal in type 1 diabetes

Stuart Turvey — 2007-06-01T08:16:46-00:00

J. Clin. Invest., Vol. 115, No. 9. (1 September 2005), pp. 2454-2461.

A major stumbling block for research on and treatment of type 1 diabetes is the inability to directly, but noninvasively, visualize the lymphocytic/inflammatory lesions in the pancreatic islets. One potential approach to surmounting this impediment is to exploit MRI of magnetic nanoparticles (MNP) to visualize changes in the microvasculature that invariably accompany inflammation. MNP-MRI did indeed detect vascular leakage in association with insulitis in murine models of type 1 diabetes, permitting noninvasive visualization of the inflammatory lesions in vivo in real time. We demonstrate, in proof-of-principle experiments, that this strategy allows one to predict, within 3 days of completing treatment with an anti-CD3 monoclonal antibody, which NOD mice with recent-onset diabetes are responding to therapy and may eventually be cured. Importantly, an essentially identical MNP-MRI strategy has previously been used with great success to image lymph node metastases in prostate cancer patients. This success strongly argues for rapid translation of these preclinical observations to prediction and/or stratification of type 1 diabetes and treatment of individuals with the disease; this would provide a crucially needed early predictor of response to therapy. 10.1172/JCI25048

Magnetic resonance imaging of the pancreas and pancreatic tumors in a mouse orthotopic model of human cancer

Jan Grimm — 2007-06-01T08:14:02-00:00

International Journal of Cancer, Vol. 106, No. 5. (2003), pp. 806-811.

Pancreatic adenocarcinoma has a rising incidence and a very poor survival rate. To develop new treatment strategies, extensive research is performed on animal models of pancreatic cancer. Orthotopic pancreatic tumors models, where the tumor is implanted into the pancreas, resemble the human disease more closely than subcutaneous tumor models, yet are difficult to monitor. In our study we report a magnetic resonance imaging (MRI) approach to visualize the pancreas in mice and to monitor orthotopically implanted pancreatic tumors. An MRI scanner was used to image normal murine pancreas and the pancreas of mice implanted with a human pancreatic adenocarcinoma cell line. Gadolinium (Gd)-DTPA-enhanced T1- and T2-weighted standard sequences were used with the objective to identify the pancreas and to monitor the growth of orthotopic tumors during 30 days. The pancreas as well as the implanted tumors could be easily identified using MRI. On T2-weighted images, the implanted tumors were easily visualized at the implantation side with high signal intensity. After application of a contrast agent, the tumors showed an enhancement. Heterogeneities within the tumor could be delineated, corresponding to histology, and the size of the tumor could be measured precisely. MR serves as a noninvasive high-resolution image modality to monitor murine pancreas as well as size, growth and even areas of heterogeneity in orthotopic pancreatic tumors. © 2003 Wiley-Liss, Inc.