Notch3/Jagged1 Circuitry Reinforces Notch Signaling and Sustains T-ALL

Autor: Maria Pelullo, Roberta Quaranta, Claudio Talora, Saula Checquolo, Samantha Cialfi, Maria Pia Felli, Geertruy te Kronnie, Chiara Borga, Zein Mersini Besharat, Rocco Palermo, Lucia Di Marcotullio, Anthony J. Capobianco, Alberto Gulino, Isabella Screpanti, Diana Bellavia
Jazyk: angličtina
Rok vydání: 2014
Předmět:
Zdroj: Neoplasia: An International Journal for Oncology Research, Vol 16, Iss 12, Pp 1007-1017 (2014)
Druh dokumentu: article
ISSN: 1476-5586
DOI: 10.1016/j.neo.2014.10.004
Popis: Deregulated Notch signaling has been extensively linked to T-cell acute lymphoblastic leukemia (T-ALL). Here, we show a direct relationship between Notch3 receptor and Jagged1 ligand in human cell lines and in a mouse model of T-ALL. We provide evidence that Notch-specific ligand Jagged1 is a new Notch3 signaling target gene. This essential event justifies an aberrant Notch3/Jagged1 cis-expression inside the same cell. Moreover, we demonstrate in Notch3-IC–overexpressing T lymphoma cells that Jagged1 undergoes a raft-associated constitutive processing. The proteolytic cleavage allows the Jagged1 intracellular domain to empower Notch signaling activity and to increase the transcriptional activation of Jagged1 itself (autocrine effect). On the other hand, the release of the soluble Jagged1 extracellular domain has a positive impact on activating Notch signaling in adjacent cells (paracrine effect), finally giving rise to a Notch3/Jagged1 auto-sustaining loop that supports the survival, proliferation, and invasion of lymphoma cells and contributes to the development and progression of Notch-dependent T-ALL. These observations are also supported by a study conducted on a cohort of patients in which Jagged1 expression is associated to adverse prognosis.
Databáze: Directory of Open Access Journals