TGFB1 and breast cancer: Our results expand on other reports demonstrating that systemic treatment with monoclonal antibodies targeting the TGFβ ligands or the TGFβRII inhibit metastatic invasion of breast cancer cells in murine tumor models [2, 13], and previous work reporting that blocking TGFβ signaling with SMIs suppresses metastasis in murine pancreatic cancer models [54], and enhances radiation response and prolongs survival in xenograft models of glioblastoma [55].