Project description:Mouse models of type I diabetes offer the potential to combine genetic approaches with other pharmacological or physiological manipulations to investigate the pathophysiology and treatment of diabetic retinopathy. Type I diabetes is induced in mice through chemical toxins or may arise spontaneously from genetic mutations. Both models are associated with retinal vascular and neuronal changes. Retinal transcriptomic responses in C57BL/6J mice treated with strepotozotocin and Ins2Akita were compared after 3 months of hyperglycemia. Specific gene expression changes suggest a neurovascular inflammatory response in diabetic retinopathy. Genes common to the two models may represent the response of the retina to hyperglycemia; while changes unique to each model may represent time-dependent disease progression differences in the various models. Further investigation of the commonalities and differences between mouse models of type I diabetes may define cause and effect events in early diabetic retinopathy disease progression.
Project description:Goal of the experiment: To identify transcriptional patterns across tumors from colorectal cancer murine models and normal mouse colon samples at different developmental stages. Experiment description: Colorectal cancer (CRC) results from multiple genetic and epigenetic events that produce variable histologies and clinical outcomes. To identify gene regulatory programs that underlie colon tumorigenesis, we profiled gene expression in 39 mouse colon tumors from four independent mouse models and compared this to mouse colon embryonic development, as well as with 100 human colon carcinomas. Here, we report a striking recapitulation of embryonic patterns of gene expression in both mouse and human colon tumors. All four of the mouse colon tumor models exhibited large-scale activation of embryonic gene expression signatures. The two nuclear beta-catenin-positive mouse tumors (azoxymethane-treated [AOM] and ApcMin/+), exhibited strong activation of genes characteristic of those expressed in the earliest embryonic stages, while tumors from two other models (Smad3-/- and Tgfb1-/- x Rag2-/-) exhibited lower activation of early stage-specific genes but substantial expression of general embryonic colon genes. Human colon cancer cases over-expressed genes characteristic of both early and late embryonic stages. Examining tumor gene expression through the lens of development has revealed an extensive network of therapeutic targets for cancer control. Keywords: Tumors from four murine models of colorectal cancer and normal mouse colon samples at different developmental stages
