1: Carcinogenesis. 2004 Jul;25(7):1299-304. Epub 2004 Feb 19. 

Defective expression of Notch1 and Notch2 in connection to alterations of c-Myc
and Ikaros in gamma-radiation-induced mouse thymic lymphomas.

Lopez-Nieva P, Santos J, Fernandez-Piqueras J.

Laboratorio de Genetica Molecular Humana, Departamento de Biologia, Facultad de
Ciencias, Universidad Autonoma de Madrid, E-28049 Madrid, Espana.

Gamma-radiation-induced thymic lymphomas constitute a heterogeneous group of
T-cell lymphomas. Some tumour suppressor genes and oncogenes have been shown to
be defective in a fraction of such lymphomas, yet a considerable number of these
remain elusive in terms of gene alterations. In the present work we present
evidence that gamma-radiation-induced thymic lymphomas in (C57BL/6 J x BALB/c)
F1 hybrid mice often exhibit increased levels of Notch1 expression, but,
contrary to what was expected, they also exhibit a clearly reduced Notch2 mRNA
expression, suggesting a cooperative antagonism of these genes. These results
represent the first reported instance for the involvement of Notch2 inactivation
in the development of thymic primary tumours while confirming the role of Notch1
as an activated oncogene. Additional analyses revealed that c-Myc
over-expression and partial inactivation of Znfn1a1/Ikaros appear to be relevant
events some how coupled to alterations in Notch genes inducing these kinds of
tumours.

PMID: 14976135 [PubMed - indexed for MEDLINE]


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