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Oncogenic activity of the regulatory subunit p85? of phosphatidylinositol 3-kinase (PI3K).

ABSTRACT: Expression of the regulatory subunit p85? of PI3K induces oncogenic transformation of primary avian fibroblasts. The transformed cells proliferate at an increased rate compared with nontransformed controls and show elevated levels of PI3K signaling. The oncogenic activity of p85? requires an active PI3K-TOR signaling cascade and is mediated by the p110? and p110? isoforms of the PI3K catalytic subunit. The data suggest that p85? is a less effective inhibitor of the PI3K catalytic subunit than p85? and that this reduced level of p110 inhibition accounts for the oncogenic activity of p85?.

SUBMITTER: Ito Y

PROVIDER: S-EPMC4250105 | biostudies-literature | 2014 Nov

REPOSITORIES: biostudies-literature

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Oncogenic activity of the regulatory subunit p85β of phosphatidylinositol 3-kinase (PI3K).

Ito Yoshihiro Y Hart Jonathan R JR Ueno Lynn L Vogt Peter K PK

Proceedings of the National Academy of Sciences of the United States of America 20141110 47

Expression of the regulatory subunit p85β of PI3K induces oncogenic transformation of primary avian fibroblasts. The transformed cells proliferate at an increased rate compared with nontransformed controls and show elevated levels of PI3K signaling. The oncogenic activity of p85β requires an active PI3K-TOR signaling cascade and is mediated by the p110α and p110β isoforms of the PI3K catalytic subunit. The data suggest that p85β is a less effective inhibitor of the PI3K catalytic subunit than p8 ...[more]

PMID: 25385636

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