PIK3CA/PTEN mutations and Akt activation as markers of sensitivity to allosteric mTOR inhibitors.

ABSTRACT:

Purpose

We sought to determine whether phosphoinositide 3-kinase (PI3K) pathway mutation or activation state and rapamycin-induced feedback loop activation of Akt is associated with rapamycin sensitivity or resistance.

Experimental design

Cancer cell lines were tested for rapamycin sensitivity, Akt phosphorylation, and mTOR target inhibition. Mice injected with breast or neuroendocrine cancer cells and patients with neuroendocrine tumor (NET) were treated with rapalogs and Akt phosphorylation was assessed.

Results

Thirty-one cell lines were rapamycin sensitive (RS) and 12 were relatively rapamycin resistant (RR; IC(50) > 100 nmol/L). Cells with PIK3CA and/or PTEN mutations were more likely to be RS (P = 0.0123). Akt phosphorylation (S473 and T308) was significantly hi

SUBMITTER: Meric-Bernstam F 

PROVIDER: S-EPMC3307149 | biostudies-literature | 2012 Mar

REPOSITORIES: biostudies-literature