Tamara A M Chessa, Piotr Jung, Arqum Anwar, Sabine Suire, Karen E Anderson, David Barneda, Anna Kielkowska, Barzan A Sadiq, Ieng Wai Lai, Sergio Felisbino, Daniel J Turnham, Helen B Pearson, Wayne A Phillips, Junko Sasaki, Takehiko Sasaki, David Oxley, Dominik Spensberger, Anne Segonds-Pichon, Michael Wilson, Simon Walker, Hanneke Okkenhaug, Sabina Cosulich, Phillip T Hawkins, Len R Stephens
The PIP3 /PI3K network is a central regulator of metabolism and is frequently activated in cancer, commonly by loss of the PIP3 /PI(3,4)P2 phosphatase, PTEN. Despite huge research investment, the drivers of the PI3K network in normal tissues and how they adapt to overactivation are unclear. We find that in healthy mouse prostate PI3K activity is driven by RTK/IRS signaling and constrained by pathway feedback. In the absence of PTEN, the network is dramatically remodeled. A poorly understood YXXM- and PIP3 /PI(3,4)P2 -binding PH domain-containing adaptor, PLEKHS1, became the dominant activator and was required to sustain PIP3 , AKT phosphorylation, and growth in PTEN-null prostate...
August 8, 2023: Molecular Cell