title: Transcriptional control of estrogen receptor in estrogen receptor-negative breast carcinoma.
abstract: The mechanisms which control estrogen receptor (ER) expression in breast carcinoma have not been elucidated. The MCF-7 (ER-positive) and MDA-MB-231 (ER-negative) breast carcinoma cell lines have been used to examine ER gene expression. Northern blot analysis of mRNA isolated from these two cell lines demonstrates that MCF-7 cells express an expected 6.5-kilobase ER mRNA whereas MDA-MB-231 do not make detectable ER message. Reverse polymerase chain reaction, which offers greater sensitivity, confirms these Northern blot results. The nuclear run-on assay was used to examine directly transcription in these two cell lines. MCF-7 cells actively transcribe the ER gene whereas no ER transcription is detected in MDA-MB-231. Southern analysis of genomic DNA confirms that the ER gene is present in MDA-MB-231. We conclude that the ER gene is controlled transcriptionally in this ER-negative breast carcinoma line.
authors.affiliation: Department of Surgery, Stanford University, California 94305.
authors.forename: R J
authors.initials: RJ
authors.lastname: Weigel
authors.forename: E C
authors.initials: EC
authors.lastname: deConinck
mesh_terms: D001483:Base Sequence; D001943:Breast Neoplasms / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D005260:Female; D006801:Humans; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D012334:RNA, Neoplasm / Q000235:genetics / Q000378:metabolism; D011960:Receptors, Estrogen / Q000235:genetics* / Q000378:metabolism; D014158:Transcription, Genetic; D014407:Tumor Cells, Cultured
chemical_list: D012333:RNA, Messenger; D012334:RNA, Neoplasm; D011960:Receptors, Estrogen