Synergistic Effects of Combined Wnt/KRAS Inhibition in Colorectal Cancer Cells
Figure 1
PKF115-584, pyrvinium pamoate and FTS activity in Ls174T cells.
(A–C) Chemical structures of PKF115-584, pyrvinium and FTS, as previously described (see ref. 20–29) (D–F) Dose-response effects of PKF115-584, pyrvinium and FTS on Ls174T cells growth. The cells were exposed at increasing doses of each inhibitor for 72 hours. MTS assay was used to evaluate the effect of the compounds on cell proliferation. IC50 values are shown for each compound. (G–H) Luciferase activity from the TOPflash plasmid was determined after incubation for 24 hours with PKF115-584 or pyrvinium. Values are Relative Light Units (RLU) with DMSO-treated cells set as 1.00. (I) Western blot analysis of active GTP-loaded KRAS pull-down (upper panel) and total KRAS (bottom) from Ls174T cells treated with FTS. (J–L) Western blot analysis showing c-myc expression in Ls174T cells treated with increasing concentrations of each compound for 48 hours. From pyrvinium-treated cells, pygopus and β-catenin expression are also shown (K). Actin is always shown as a loading control. (M–N) Quantitative PCR analysis of AXIN2 and CCND1/cyclin D1 expression after treatment with increasing doses (0.125–1.0 μM) of PKF115-584 (M) and pyrvinium (N). (O) Western blot analysis of MEK phosphorylation in FTS-treated cells. Total MEK and actin are shown as controls. (P–Q) Dose-response curves of PKF115-584 and pyrvinium in the absence (empty circles) or presence (filled circles) of 100 μM FTS. Each individual curve is normalized on the corresponding sample with no β-catenin inhibitor.