Expression data from tumoral thymocytes and DP thymocytes expressing an activated form of b-catenin in mouse T cells

To assess the importance of the Wnt pathway during T cell develoment, we generated a mouse line (R26-βcat) in which high levels of active β-catenin are maintained throughout T cell development. Young R26-βcat mice (6-week-old) show a differentiation block at the CD4+CD8+ DP stage. All R26-βcat mice develop T cell leukemias with a DP phenotype at 5-6 months of age. To identify the molecular pathways involved in tumor development, we profiled the global gene expression of transformed and pre-transformed DP cells. Thymocytes from 6-week-old mice (with a normal sized thymus and a polyclonal thymocyte population) were used to define the pre-transformed transcriptome. RNA from control and pre-leukemic R26-βcat DP thymocytes as well as R26-βcat total tumor cells were extracted and used for transcriptome analysis.