Fig. 2.

ThPOK^const lymphomas show Notch induction and resemble dominant-negative (DN) Ikaros lymphomas. (A) RT-PCR analysis of Hes1, Deltex1, and Notch3 mRNA expression in total thymocytes from three different 2- to 3-mo-old ThPOK^const mice, typed as “lymphoma” positive, according to enlarged thymus size and altered thymocyte subset distribution (green columns). Expression of the same genes is shown for total thymocytes from three WT control mice (purple columns). (B) Notch1 mutations from three independent ThPOK^const lymphomas. (C) Oligonucleotide microarray gene expression comparison of ThPOK^const lymphomas with other mouse T-cell lymphomas. Unsupervised hierarchical clustering indicates closest similarity to Ikaros DN lymphomas. (D) Comparison of human ThPOK RNA expression levels by RT-PCR (normalized for GAPDH), in panel of human T-ALL cell lines.