NR4A1 and breast cancer: Next we analyzed a panel of breast cancer cell lines, containing highly-invasive cell lines (MDA-MB-231 and MDA-MB-468) that are metastatic in animal models, as well as hormone receptor-positive cell lines (ZR-75–1, T47D and SKBR3) that are not metastatic in vivo, for VASP phosphorylations.