Phosphoinositide 3-kinase p110beta activity : key role in metabolism and mammary gland cancer but not development
Date Issued
2008-01-01
Author(s)
Ciraolo, Elisa
Iezzi, Manuela
Marengo, Stefano
Curcio, Claudia
Costa, Carlotta
Azzolino, Ornella
Gonella, Cristiano
Rubinetto, Cristina
Wu, Haiyan
Dastrù, Walter
Martin, Erica L
Silengo, Lorenzo
Altruda, Fiorella
Turco, Emilia
Lanzetti, Letizia
Musiani, Piero
Rückle, Thomas
Rommel, Christian
Backer, Jonathan M
Forni, Guido
Hirsch, Emilio
DOI
10.1126/scisignal.1161577
Abstract
The phosphoinositide 3-kinase (PI3K) pathway crucially controls metabolism and cell growth. Although different PI3K catalytic subunits are known to play distinct roles, the specific in vivo function of p110beta (the product of the PIK3CB gene) is not clear. Here, we show that mouse mutants expressing a catalytically inactive PIK3CB(K805R) mutant survived to adulthood but showed growth retardation and developed mild insulin resistance with age. Pharmacological and genetic analyses of p110beta function revealed that p110beta catalytic activity is required for PI3K signaling downstream of heterotrimeric guanine nucleotide-binding protein (G protein)-coupled receptors as well as to sustain long-term insulin signaling. In addition, PIK3CB(K805R) mice were protected in a model of ERBB2-driven tumor development. These findings indicate an unexpected role for p110beta catalytic activity in diabetes and cancer, opening potential avenues for therapeutic intervention.