The exogenous β-catenin signaling induces an up-regulation of p53 expression in HONE1 hybrid cells and influences proliferation of treated cells. A. RT-PCR analysis shows that tumor suppressor p53 is up-regulated by Wnt-signaling in HONE1 hybrid cells compared to parental HONE1 cells. Western blot analysis (right) confirms that p53 expression is also up-regulated in HONE1 hybrid cells (MCH4.4/4.5/4.6). B. shRNA knockdown of β-catenin is associated with the reduction of tumor cell proliferation. MTT assays indicate cell proliferation rate is reduced in β-catenin shRNA infected HONE1 hybrid cells in different starting number of cells compared to scramble shRNA control cells. C. The colony formation assay was performed in matrigel. The colony formation ability in HONE1 hybrid cells with infected β-catenin shRNA is significantly inhibited on both days 7 and 14 compared to scramble shRNA control cells.