First Author | Göthert JR | Year | 2007 |
Journal | Blood | Volume | 110 |
Issue | 10 | Pages | 3753-62 |
PubMed ID | 17698635 | Mgi Jnum | J:125689 |
Mgi Id | MGI:3759583 | Doi | 10.1182/blood-2006-12-063644 |
Citation | Gothert JR, et al. (2007) NOTCH1 pathway activation is an early hallmark of SCL T-leukemogenesis. Blood 110(10):3753-62 |
abstractText | The acquired activation of stem cell leukemia (SCL) during T lymphopoiesis is a common event in T-cell acute lymphoblastic leukemia (T-ALL). Here, we generated tamoxifen (TAM)-inducible transgenic mice (lck-ER(T2)-SCL) to study the consequences of acquired SCL activation during T-cell development. Aberrant activation of SCL in thymocytes resulted in the accumulation of immature CD4(+)CD8(+) (double-positive, DP) cells by preventing normal surface expression of the T-cell receptor alphabeta (TCRalphabeta) complex. SCL-induced immature DP cells were further characterized by up-regulated NOTCH1 and generated noncycling polyclonal CD8(+)TCRbeta(low) cells. The prevalence of these cells was SCL dependent because TAM withdrawal resulted in their disappearance. Furthermore, we observed that SCL activation led to a dramatic up-regulation of NOTCH1 target genes (Hes-1, Deltex1, and CD25) in thymocytes. Strikingly, NOTCH1 target gene up-regulation was already observed after short-term SCL induction, implying that enhanced NOTCH signaling is mediated by SCL and is not dependent on secondary genetic events. These data represent the basis for a novel pathway of SCL-induced leukemogenesis and provide a functional link between SCL and NOTCH1 during this process. |