Notch1-induced brain tumor models the sonic hedgehog subgroup of human medulloblastoma.

TitleNotch1-induced brain tumor models the sonic hedgehog subgroup of human medulloblastoma.
Publication TypeJournal Article
Year of Publication2013
AuthorsNatarajan S, Li Y, Miller EE, Shih DJ, Taylor MD, Stearns TM, Bronson RT, Ackerman SL, Yoon JK, Yun K
JournalCancer research
Volume73
Issue17
Pagination5381-90
Date Published2013 Sep 1
Abstract

While activation of the Notch pathway is observed in many human cancers, it is unknown whether elevated Notch1 expression is sufficient to initiate tumorigenesis in most tissues. To test the oncogenic potential of Notch1 in solid tumors, we expressed an activated form of Notch1 (N1ICD) in the developing mouse brain. N1ICD;hGFAP-cre mice were viable but developed severe ataxia and seizures, and died by weaning age. Analysis of transgenic embryo brains revealed that N1ICD expression induced p53-dependent apoptosis. When apoptosis was blocked by genetic deletion of p53, 30% to 40% of N1ICD;GFAP-cre;p53(+/-) and N1ICD;GFAP-cre;p53(-/-) mice developed spontaneous medulloblastomas. Interestingly, N1ICD-induced medulloblastomas most closely resembled the sonic hedgehog subgroup of human medulloblastoma at the molecular level. Surprisingly, N1ICD-induced tumors do not maintain high levels of the Notch pathway gene expression, except for Notch2, showing that initiating oncogenic events may not be decipherable by analyzing growing tumors in some cases. In summary, this study shows that Notch1 has an oncogenic potential in the brain when combined with other oncogenic hits, such as p53 loss, and provides a novel mouse model of medulloblastoma. Cancer Res; 73(17); 5381-90. ©2013 AACR.

DOI10.1088/0957-4484/24/31/315203
Alternate JournalCancer Res.