title: Ada3 requirement for HAT recruitment to estrogen receptors and estrogen-dependent breast cancer cell proliferation.
abstract: We have previously shown that evolutionarily conserved alteration/deficiency in activation (Ada) protein associates with and promotes estrogen receptor (ER)-mediated target gene expression. Here, we examined the role of endogenous Ada3 to recruit histone acetyl transferases (HAT) to an ER-responsive promoter and its role in estrogen-dependent cell proliferation and malignant phenotype. Using a combination of glycerol gradient cosedimentation and immunoprecipitation analyses, we show that Ada3, ER, and three distinct HATs [p300, (p300/CBP-associated factor) PCAF, and general control nonrepressed 5 (Gcn5)] are present in a complex. Using chromatin immunoprecipitation analysis, we show that short hairpin RNA (shRNA)-mediated knockdown of Ada3 in ER-positive breast cancer cells significantly reduced the ligand-dependent recruitment of p300, PCAF, and Gcn5 to the ER-responsive pS2 promoter. Finally, we use shRNA knockdown to show that Ada3 is critical for estrogen-dependent proliferation of ER-positive breast cancer cell lines in two-dimensional, as well as three-dimensional, culture. Knockdown of Ada3 in ER-positive MCF-7 cells induced reversion of the transformed phenotype in three-dimensional culture. Thus, our results show an important role of Ada3 in HAT recruitment to estrogen-responsive target gene promoters and for estrogen-dependent proliferation of breast cancer cells.
authors: Divisions of Cancer Biology, Evanston Northwestern Healthcare Research Institute, Northwestern University, Evanston, Illinois, USA.
authors: Aleksandra
authors: A
authors: Germaniuk-Kurowska
authors: Alo
authors: A
authors: Nag
authors: Xiangshan
authors: X
authors: Zhao
authors: Manjari
authors: M
authors: Dimri
authors: Hamid
authors: H
authors: Band
authors: Vimla
authors: V
authors: Band
mesh_terms: D001943:Breast Neoplasms / Q000235:genetics / Q000473:pathology* / Q000503:physiopathology*; D002455:Cell Division; D045744:Cell Line, Tumor; D002843:Chromatin / Q000235:genetics; D003094:Collagen; D004338:Drug Combinations; D004967:Estrogens; D005260:Female; D051548:Histone Acetyltransferases / Q000378:metabolism*; D006801:Humans; D007797:Laminin; D011509:Proteoglycans; D012334:RNA, Neoplasm / Q000235:genetics; D011960:Receptors, Estrogen / Q000502:physiology*; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism
chemical_list: D002843:Chromatin; D004338:Drug Combinations; D004967:Estrogens; D007797:Laminin; D011509:Proteoglycans; D012334:RNA, Neoplasm; D011960:Receptors, Estrogen; C444103:TADA3 protein, human; D014157:Transcription Factors; C059485:matrigel; D003094:Collagen; D051548:Histone Acetyltransferases