title: ER and PI3K independently modulate endocrine resistance in ER-positive breast cancer.
abstract: Endocrine therapy-resistant estrogen receptor-positive (ER(+)) breast cancer is the most common cause of breast cancer death. Miller and colleagues demonstrate that ligand-independent ER activity promotes the growth of breast cancer cells through CDK4/E2F. As an independent event, the phosphatidylinositol 3-kinase (PI3K) pathway is also upregulated in endocrine therapy-resistant cells. Promising preclinical evidence by several groups for the combination of an inhibitor of ligand-independent ER, fulvestrant, with PI3K inhibition, has led to the activation of trials evaluating this concept.
authors.affiliation: Division of Oncology, Department of Medicine, Washington University in Saint Louis, St. Louis, Missouri 63110, USA.
authors.forename: Brian A
authors.initials: BA
authors.lastname: Van Tine
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Crowder
authors.forename: Matthew J
authors.initials: MJ
authors.lastname: Ellis
mesh_terms: D000818:Animals; D001943:Breast Neoplasms / Q000235:genetics*; D050684:E2F Transcription Factors / Q000235:genetics* / Q000378:metabolism*; D047628:Estrogen Receptor alpha / Q000235:genetics* / Q000378:metabolism*; D004967:Estrogens / Q000172:deficiency*; D005260:Female; D006801:Humans
chemical_list: D050684:E2F Transcription Factors; D047628:Estrogen Receptor alpha; D004967:Estrogens
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