title: T47D breast cancer cells switch from ER/HER to HER/c-Src signaling upon acquiring resistance to the antiestrogen fulvestrant.
abstract: In this study, T47D cell lines resistant to the antiestrogen fulvestrant were established and analyzed to explore, whether a switch to HER signaling, as seen in fulvestrant resistant MCF-7 cell lines, is a general resistance mechanism. We find that parental T47D cells depend on ER and HER signaling for growth. Fulvestrant resistant T47D cells have lost ER expression and, although HER2 was over expressed, growth was only partially driven by HER receptors. Instead c-Src was important for resistant growth. Thus, the T47D and MCF-7 model system unravel different resistance mechanisms which may be important for fulvestrant resistant breast cancer patients.
authors: Breast Cancer Group, Cell Death and Metabolism, Danish Cancer Society Research Center, Copenhagen, Denmark. Electronic address: tki@cancer.dk.
authors: Tove
authors: T
authors: Kirkegaard
authors: Breast Cancer Group, Cell Death and Metabolism, Danish Cancer Society Research Center, Copenhagen, Denmark.
authors: Susanne K
authors: SK
authors: Hansen
authors: Breast Cancer Group, Cell Death and Metabolism, Danish Cancer Society Research Center, Copenhagen, Denmark.
authors: Sarah L
authors: SL
authors: Larsen
authors: Breast Cancer Group, Cell Death and Metabolism, Danish Cancer Society Research Center, Copenhagen, Denmark.
authors: Birgit E
authors: BE
authors: Reiter
authors: Department of Clinical Biochemistry, Aarhus University Hospital, Aarhus, Denmark.
authors: Boe S
authors: BS
authors: Sørensen
authors: Breast Cancer Group, Cell Death and Metabolism, Danish Cancer Society Research Center, Copenhagen, Denmark.
authors: Anne E
authors: AE
authors: Lykkesfeldt
mesh_terms: D015153:Blotting, Western; D001943:Breast Neoplasms / Q000378:metabolism*; D000081247:CSK Tyrosine-Protein Kinase; D045744:Cell Line, Tumor; D019008:Drug Resistance, Neoplasm / Q000502:physiology*; D004958:Estradiol / Q000031:analogs & derivatives / Q000494:pharmacology; D004965:Estrogen Antagonists / Q000494:pharmacology; D000077267:Fulvestrant; D006801:Humans; D047468:Immunoprecipitation; D034741:RNA, Small Interfering; D060888:Real-Time Polymerase Chain Reaction; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism*; D011960:Receptors, Estrogen / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction / Q000502:physiology*; D019061:src-Family Kinases / Q000378:metabolism*
chemical_list: D000081247:CSK Tyrosine-Protein Kinase; D004958:Estradiol; D004965:Estrogen Antagonists; D000077267:Fulvestrant; D034741:RNA, Small Interfering; D018719:Erb-b2 Receptor Tyrosine Kinases; D011960:Receptors, Estrogen; D019061:src-Family Kinases; C508053:ERBB2 protein, human; C000631346:CSK protein, human