Maintenance of Hormone Responsiveness in Luminal Breast Cancers by Suppression of Notch

ABSTRACT: Luminal breast cancers express estrogen (ER) and/or progesterone (PR) receptors and respond to hormone therapies. Basal-like “triple negative” (TN) cancers lack steroid receptors but are cytokeratin (CK) 5-positive and require chemotherapy. Here we show that over half of primary ER+PR+ breast cancers contain an ER–PR–CK5+ “luminobasal” subpopulation exceeding 1% of cells. Starting from ER+PR+ luminal cell lines, we generated novel lines with varying luminal to luminobasal-cell ratios and studied their molecular and biological properties. In luminal disease, luminobasal cells expand in response to antiestrogen or estrogen withdrawal therapies. The phenotype and gene signature of the hormone resistant cells matches that of clinical TN basal-like and claudin-low disease. Luminobasal-cell expa

ORGANISM(S): Homo sapiens

SUBMITTER: Charles Perou 

PROVIDER: E-GEOD-31870 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress