Figure 1

PI3Kγ plays a key role in IGF-I-induced migration of MDA-MB-231 cells. (A) MDA-MB-231 cells or MDA-MB-231 CXCR4 knock-down cells were treated with 0.1 nM IGF-I and Akt phosphorylation was assessed. (B) Akt phosphorylation was quantified by densitometry, normalized to β-actin and expressed as a value relative to the 10-minute control values. (C) MDA-MB-231 cells were treated with DMSO (diluent control) or 10 μM IC87114 for 1 hour and chemotaxis in response to IGF-I assessed. (D) MDA-MB-231 cells were treated with diluent or 2 μM AS605240 for 1 hour and chemotaxis in response to IGF-I assessed. * - significantly different from the control values at, p<0.05 (E) MDA-MB-231 cells were incubated in serum-free medium for 1 hour and stimulated with 0.1 nM IGF-I for 5 min. Cell membrane fractions were analyzed by SDS-PAGE and Western blot using anti-p110γ antibody. The Western-blots were stripped and reprobed with anti-pan-cadherin antibodies as a loading control. (F) Membrane translocation of p110γ was quantified by densitometry analysis of three independent experiments. * - significantly different from the control values at, p<0.05 (G) MDA-MB-231 cells were either treated with diluent or 2 μM AS605240 for 1 hour and Akt phosphorylation was assessed. (H) Akt phosphorylation was quantified by densitometry, normalized to β-actin and expressed as a value relative to the 10-minute control-treated values. * - significantly different from the control values (2-way ANOVA with Bonferroni post-test) at ***, p<0.001. Unless otherwise stated, data are expressed as mean ± sem from at least three experiments.