Project description:To examine Ikaros tumor suppressor mechanisms, we have utilized inducible RNAi to dynamically restore endogenous Ikaros expression in T-ALL driven by its knockdown. This causes rapid transcriptional repression of Notch1 and associated targets including Myc, even in leukemias harboring spontaneous activating Notch1 mutations (producing aberrant ICN1) similar to those found in 60% of human T-ALL. Ikaros restoration results in sustained regression of Notch1-wild type leukemias while endogenous or engineered ICN1 expression promotes rapid disease relapse, indicating that ICN1 functionally antagonizes Ikaros in T-ALL. RNA-seq was performed on T-ALL (Vav-tTA;TRE-GFP-shIkaros primary leukemia ALL211) cells isolated from two untreated and two 3-day Dox-treated mice.
Project description:To examine Ikaros tumor suppressor mechanisms, we have utilized inducible RNAi to dynamically restore endogenous Ikaros expression in T-ALL driven by its knockdown. This causes rapid transcriptional repression of Notch1 and associated targets including Myc, even in leukemias harboring spontaneous activating Notch1 mutations (producing aberrant ICN1) similar to those found in 60% of human T-ALL. Ikaros restoration results in sustained regression of Notch1-wild type leukemias while endogenous or engineered ICN1 expression promotes rapid disease relapse, indicating that ICN1 functionally antagonizes Ikaros in T-ALL. RNA-seq was performed on T-ALL (Vav-tTA;TRE-GFP-shIkaros primary leukemia ALL65) cells isolated from three untreated and three 3-day Dox-treated mice. There were two sequencing runs of each RNA sample.
Project description:To examine Ikaros tumor suppressor mechanisms, we have utilized inducible RNAi to dynamically restore endogenous Ikaros expression in T-ALL driven by its knockdown. This causes rapid transcriptional repression of Notch1 and associated targets including Myc, even in leukemias harboring spontaneous activating Notch1 mutations (producing aberrant ICN1) similar to those found in 60% of human T-ALL. Ikaros restoration results in sustained regression of Notch1-wild type leukemias while endogenous or engineered ICN1 expression promotes rapid disease relapse, indicating that ICN1 functionally antagonizes Ikaros in T-ALL. RNA-seq was performed on T-ALL (Vav-tTA;TRE-GFP-shIkaros primary leukemia ALL101) cells isolated from three untreated and three 3-day Dox-treated mice. There were two sequencing runs of each RNA sample.
Project description:TAZ-CAMTA1 is a defining genetic aberration in the vascular cancer epithelioid hemangioendothelioma. We generated a novel transgenic mouse that expresses TAZ-CAMTA1 in endothelial cells. These mice develop vascular tumors in the lung and die by average on day 40. We isolated GFP + endothelial cells from three five-week old TRE-TAZ-CAMTA1;Cdh5-tTA;TRE-GFP mice and subjected these endothelial cells to scRNA-seq via the 10X genomics platform
Project description:Lmo2 is an oncogenic transcription factor that is a frequent target of chromosomal abnormalities in this T-cell acute lymphoblastic leukemia (T-ALL). In transgenic mouse models, overexpression of Lmo2 causes thymocyte self-renewal leading to T-cell leukemia with long latency. However, the requirement of Lmo2 for maintenance of overt leukemia is poorly understood. We found that Lyl1, a critical cofactor for Lmo2-induced leukemia, is frequently lost in cell lines derived from Lmo2-transgenic mice, raising the possibility that Lmo2 function is dispensable at this stage. To study this, we developed a Tetracycline-repressible knock-in mouse model (Vav-TRE-Lmo2), which expresses Lmo2 throughout the haematopoietic system. This led to specific effects on T-cell development and the development of T-cell leukemia with long latency, preceded by the presence of self-renewing T-cells in the thymus. Repression of Lmo2 overcame the Lmo2-induced thymocyte developmental block at the preleukemic stage and led to elimination of Lmo2-induced thymocyte self-renewal in vivo. In contrast, Lmo2 function was dispensable for the majority of overt Lmo2-induced T-cell leukemias as well as leukemia-derived cell lines, implying an evolution of oncogene addiction in the majority of T-cell leukemias. Lmo2-dependence in T-ALL was associated with an immature gene expression profile, but could not be predicted by immunophenotype or assessment of Notch pathway activation. Thus, Lmo2 can give rise to both Lmo2-depenent and –independent T-cell leukemias. The Vav-TRE-Lmo2 model should be useful to determine the molecular features associated with Lmo2-dependence, as well as the critical components of the Lmo2-induced self-renewal pathways in T-ALL.
Project description:Ikaros family DNA binding proteins are critical regulators of B cell development. To identify Ikaros-regulated genes in primary pre-B cells we performed gene expression microarrays. We used retroviral gene transfer to express Ikaros proteins. Total RNA from 3 biological replicates of primary pre-B cells transduced with wild type Ikaros (HA-Ikaros-IRES-GFP) and control vector (IRES-GFP) was isolated 48h after infection.
Project description:Identification of critical survival determinants of PDGF-driven proneural glioma. Results provided information about the genes and pathways that are regulated by PDGF signaling in PDGF-driven proneural glioma and led to the assessment of the importance of the USP1-ID2 axis in proneural glioma. Total RNA obtained from PDGF-driven glioma spheroid cells (PDGF-GSC) and primary tumors arising in the Gfap-tTa/Tre-PDGFB mouse model used in our study was analyzed to determine to which subtype of GBM these specimens belonged.