CEACAM6 expression in tumours treated with a PI3K/AKT inhibitor. A) Subconfluent cultures of Detroit 562 cells transduced with vector (pLV101), knockdown construct (mir CEA Dux) or overexpression vector (pLV101-CEA) were exposed to varying concentrations of BGT226 for 48 hours after which viability was assessed. Data presented as mean ± sem from 2 experiments performed in triplicate. B) Protein was harvested from untreated cells used in (A) and CEACAM6, AKT or phospho-S437 AKT protein expression estimated by western blot. β-actin expression is presented to confirm loading equivalence. C) 106 cells used in (A) were injected into NOD/SCID mice and when tumours reached 0.4 cm3 the mice were treated with daily doses of vehicle or BGT226 as described elsewhere. Mice were sacrificed when tumours reached 1 cm3 and tumours removed, fixed and 5 μm sections stained for CEACAM6 expression. Note mice treated with BGT226 displayed significant reductions in tumour growth and time to sacrifice was significantly extended in these mice. An IgG negative control is shown on the left. Six mice per group were used and a representative section from one mouse is shown. 20X magnification.