Figure 6: Cells expressing truncated APC can form a functional destruction complex.
From: Wnt secretion is required to maintain high levels of Wnt activity in colon cancer cells
(a) β-Catenin bound to the main components of the destruction complex in DLD1 cells is phosphorylated. DLD1 cells were subjected to immunoprecipitation with anti-APC, -GSK3β or -Axin1 antibody. Western blottings are representative of three independent experiments. (b,c) A moderate decrease in APC level is not sufficient to induce Wnt signalling, but sensitizes cells to Wnt3a. RKO colon cancer cells that express wild-type APC and are stably transfected with a TCF4/Wnt reporter were transduced with the indicated shRNA constructs. (b) Luciferase activity was measured in RKO TCF4/Wnt cells treated with the indicated amounts of recombinant Wnt3a protein for 24 or 48 h. (c) Relative expression of APC and AXIN2 was measured by quantitative PCR. (b,c) Results of six (b) and three (c) independent experiments are shown as mean±s.e.m.
