ZFHX3 and breast carcinoma: ATBF1 not only inhibits the proliferation of ER-positive cells in both normal mammary gland and breast cancer cells, it is also frequently inactivated by genomic deletion and downregulation in human breast cancers, and its downregulation is associated with worse patient survival in ER-positive breast cancer [4], [6], [7] (our unpublished data).