5 ml of agar was then added to each suspension, SB-715992 cost mixed well

and 1.5 ml was dispensed onto each pre-set agar plate, in triplicate, giving a final concentration of 1.5 × 104 cells per plate. The plates were placed on trays containing a small volume of water to prevent the agar from drying out. On day 0, cells were counted and FK228 subsequently cultured for an additional 10 days. After this time the colonies were counted using an inverted microscope at 400×. Ten areas were viewed per plate and the total number of colonies present was extrapolated and the percentage colony forming efficiency (CFE) was determined by expressing the number of colonies formed after 10 days as a percentage of the number of cells counted on day 0. Immunoblotting

Whole protein was extracted from cell lysates using 1× lysis buffer (50 mM Tris-Cl, 150 mM NaCl, and 0.5% NP-40). Lysates were centrifuged for 10 min at 14,000 rpm at 4°C. Protein concentrations were determined using the Bio-Rad protein assay according to manufacturer’s instructions (Bio-Rad). 35 μg of protein was separated by 7.5% SDS-PAGE under reducing conditions. Proteins were transferred to nitrocellulose membrane (Amersham). SN-38 Membranes were blocked at 4°C overnight in TBS (25 mM Tris-HCl, pH 7.4, 150 mM NaCl, 2.7 mM KCl) containing 5% (w/v) lowfat milk powder. Membranes were probed with specific antibodies. Anti-β1 (MAB1951Z-20), anti-α5 (AB1949) and anti-α6 (MAB1982) were obtained from Chemicon (Millipore, Europe). Beta-actin was used as loading control (Sigma, A5441). Membranes were washed 3× for 5 min with PBS-Tween-20 (0.1%) and incubated with secondary antibodies, anti-mouse and anti-rabbit (Sigma) for 1 hr at room temperature and washing step repeated. Protein bands were detected with Luminol reagent (Santa Cruz Biotechnology). Integrin siRNA transfection Two integrin

β1 (ITGB1) target siRNAs (#109877, #109878 (validated) Ambion Inc.) were used to silence integrin β1 expression. Two integrin α5 (ITGA5) target siRNAs (#106728, #111113 Ambion Inc.) and two integrin α6 (ITGA6) target siRNAs (#8146, #103827 (validated) Ambion Inc.) were used to silence the respective target genes. Solutions of siRNA at a final concentration of 30 nM were Avelestat (AZD9668) prepared in OptiMEM (Gibco™). NeoFX solution was prepared in OptiMEM and incubated at room temperature for 10 min. After incubation, an equal volume of neoFX solution was added to each siRNA solution, mixed well and incubated for a further 10 min. 100 μl of neoFX/OptiMEM solutions were added into a 6 well plate in duplicate. Clone #8 (3 × 105) cells were added onto the siRNA solution. The plates were gently mixed and incubated for 24 hours. The transfection mixture was removed and replaced with fresh medium. Positive control, kinesin (Ambion Inc.) was included in each triplicate experiment. Invasion, motility, adhesion and anoikis assays were then carried out 48 hours after transfection, as previously described.