Figure 1

CBFβ is associated with Runx2 in the metastatic breast cancer cell line MDA-MB-231. (A) Western blot showing CBFβ expression in MDA-MB-231 cells. Total extracts from metastatic (MDA-MB-231) and non-metastatic (MCF-7) breast cancer cell lines were subjected to western blotting analysis with a CBFβ antibody. HeLa cells known to express CBFβ were used as positive controls. Protein levels of Tubulin are shown as an internal loading control. (B) CBFβ and Runx2 are nuclear in MD-MB-231 cells. Nuclear extracts from MDA-MB-231 and MCF-7 cells were utilized to determine the localisation of Runx2 and CBFβ. Lamin B1 was used as loading control. (C) Western blot showing Runx2 expression in MDA-MB-231 cells. Total extracts from metastatic (MDA-MB-231) and non-metastatic (MCF-7) breast cancer cell lines were subjected to western blotting analysis with a Runx2 antibody. The UMR-106 and HeLa cells were used as positive and negative controls for Runx2 expression, respectively. Protein levels of Tubulin are shown as an internal loading control. (D) Runx2 interacts with CBFβ in MDA-MB-231 cells. Whole extracts of the UMR-106 and MDA-MB-231 cells were subject to immunoprecipitation (IP) assays. A monoclonal antibody against Runx2 was used to immunoprecipitate the Runx2 protein. Then, immunoblots with a polyclonal antibody anti-CBFβ (upper) or a whole serum anti-Runx2 (lower) were used to determine the presence of CBFb and Runx2, respectively. IgG antibody was used as a specificity control. Whole extracts of the cells (input) were used as control for CBFβ and Runx2 expression.