title: Induction of serum amyloid A genes is associated with growth and apoptosis of HC11 mammary epithelial cells.
abstract: In this study, we examined the expression and functions of serum amyloid A (SAA) isoforms during apoptosis of HC11 mammary gland epithelial cells. Expression of SAA mRNAs and apoptosis were increased in HC11 cells by serum withdrawal and gradually decreased upon the addition of serum, or epidermal growth factor (EGF). TNFalpha treatment of HC11 cells also induced expression of SAA genes, and the effect on SAA1 and SAA2 expression was suppressed by treatment with MG132, and in cells transfected with a dominant negative mutant form of IkappaBalpha. Similar results were observed in response to interleukin-1 (IL-1), IL-6 and interferon gamma (IFNgamma). Furthermore, overexpression of the SAA1 and SAA2 isoforms suppressed growth and accelerated apoptosis of HC11 cells by increasing caspase 3/7 and caspase 8 activities, but the apoptotic effect of tumor necrosis factor alpha (TNFalpha) on HC11 cells was not enhanced. We found that expression of SAA1 and SAA2, but not SAA3, was regulated by an NFkappaB-dependent pathway, and that overexpression of SAA isoforms accelerated the apoptosis of HC11 cells.
authors.affiliation: School of Agriculture and Biotechnology, College of Agriculture and Life Sciences, Seoul National University, Seoul, South Korea.
authors.forename: Yoonjung
authors.initials: Y
authors.lastname: Kho
authors.forename: Sungchan
authors.initials: S
authors.lastname: Kim
authors.forename: Byung Sun
authors.initials: BS
authors.lastname: Yoon
authors.forename: Jai-Hee
authors.initials: JH
authors.lastname: Moon
authors.forename: Bona
authors.initials: B
authors.lastname: Kim
authors.forename: Sungwook
authors.initials: S
authors.lastname: Kwak
authors.forename: Junghee
authors.initials: J
authors.lastname: Woo
authors.forename: Sejong
authors.initials: S
authors.lastname: Oh
authors.forename: Kichang
authors.initials: K
authors.lastname: Hong
authors.forename: Saehun
authors.initials: S
authors.lastname: Kim
authors.forename: Hyunggee
authors.initials: H
authors.lastname: Kim
authors.forename: Seungkwon
authors.initials: S
authors.lastname: You
authors.forename: Yunjaie
authors.initials: Y
authors.lastname: Choi
mesh_terms: D000818:Animals; D017209:Apoptosis; D002454:Cell Differentiation; D002455:Cell Division; D002478:Cells, Cultured; D004847:Epithelial Cells / Q000166:cytology* / Q000502:physiology*; D005260:Female; D008321:Mammary Glands, Animal / Q000166:cytology* / Q000502:physiology*; D051379:Mice; D020033:Protein Isoforms / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics; D011994:Recombinant Proteins / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D000685:Serum Amyloid A Protein / Q000235:genetics* / Q000378:metabolism; D014162:Transfection
chemical_list: D020033:Protein Isoforms; D012333:RNA, Messenger; D011994:Recombinant Proteins; D000685:Serum Amyloid A Protein