Figure 4 THOR directly binds to β-catenin mRNA, enhances its mRNA stability and expression. (A–C) The mRNA and protein levels of Sox9 and β-catenin were examined in TNBC cells with THOR knockdown or not. (D) The in vitro RNA-RNA interaction was performed to examine the THOR-β-catenin RNA interaction in TNBC cells. (E) RIP assay on THOR level in RNA pulled down by anti-β-catenin. (F, G) Analysis on the mRNA stability of β-catenin was performed in TNBC cells with THOR knockdown or not. (H) Luciferase reporter analysis on the TOPflash and FOPflash in MDA-MB-453 cells with THOR knockdown or not. (I) The expression of the downstream effectors of β-catenin was detected in TNBC cells with THOR knockdown or not. ** P<0.01. mRNA – messenger RNA; TNBC – triple negative breast cancer; RIP – RNA immunoprecipitation.