title: E4F1, a novel estrogen-responsive gene in possible atheroprotection, revealed by microarray analysis.
abstract: Estrogen has been postulated to be involved in inhibition of vascular smooth muscle cell (VSMC) proliferation mainly via estrogen receptor (ER), but the detailed mechanism has remained primarily unknown. Therefore, in this study, microarray analysis was used in two types of cultured human VSMCs: one positive for ER alpha, and the other for ER beta, which were treated by estrogens to detect the estrogen-responsive genes. We also used quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) to evaluate mRNA levels of selective target gene (TG) in these cells. We further studied whether the TG product was involved in inhibition of proliferation using small interfering RNA (siRNA) of the TG transfection. We subsequently used quantitative RT-PCR and in situ hybridization analysis to evaluate the expression of these gene products in human aorta. E4F1, a possible inducer of cell growth arrest, was markedly increased only in ER alpha-positive VSMCs by estrogens in both microarray and RT-PCR analyses. Blocking of E4F1 using siRNA suppressed estrogenic inhibition of ER alpha-positive VSMC proliferation. E4F1 mRNA was abundant in premenopausal female aorta with mild atherosclerotic changes. E4F1 is therefore considered one of the estrogen-responsive genes involving ER alpha-mediated inhibition of VSMC proliferation and may play an important role in estrogen-related atheroprotection of human aorta.
authors.affiliation: Department of Pathology, Tohoku University School of Medicine, Aoba-ku, Sendai 980-8575, Japan. nakamura@patholo2.med.tohoku.ac.jp
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Nakamura
authors.forename: Katsuhide
authors.initials: K
authors.lastname: Igarashi
authors.forename: Takashi
authors.initials: T
authors.lastname: Suzuki
authors.forename: Jun
authors.initials: J
authors.lastname: Kanno
authors.forename: Tohru
authors.initials: T
authors.lastname: Inoue
authors.forename: Chika
authors.initials: C
authors.lastname: Tazawa
authors.forename: Masayuki
authors.initials: M
authors.lastname: Saruta
authors.forename: Tomoko
authors.initials: T
authors.lastname: Ando
authors.forename: Noriko
authors.initials: N
authors.lastname: Moriyama
authors.forename: Toru
authors.initials: T
authors.lastname: Furukawa
authors.forename: Masao
authors.initials: M
authors.lastname: Ono
authors.forename: Takuya
authors.initials: T
authors.lastname: Moriya
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Ito
authors.forename: Haruo
authors.initials: H
authors.lastname: Saito
authors.forename: Tadashi
authors.initials: T
authors.lastname: Ishibashi
authors.forename: Shoki
authors.initials: S
authors.lastname: Takahashi
authors.forename: Shogo
authors.initials: S
authors.lastname: Yamada
authors.forename: Hironobu
authors.initials: H
authors.lastname: Sasano
mesh_terms: D017504:Adenovirus E4 Proteins / Q000037:antagonists & inhibitors / Q000235:genetics* / Q000378:metabolism; D001011:Aorta / Q000737:chemistry / Q000378:metabolism* / Q000473:pathology; D001161:Arteriosclerosis / Q000378:metabolism / Q000517:prevention & control*; D049109:Cell Proliferation / Q000187:drug effects; D047628:Estrogen Receptor alpha / Q000032:analysis / Q000235:genetics; D047629:Estrogen Receptor beta / Q000032:analysis / Q000235:genetics; D004967:Estrogens / Q000494:pharmacology*; D005260:Female; D020869:Gene Expression Profiling; D006801:Humans; D046228:Microarray Analysis; D009131:Muscle, Smooth, Vascular / Q000166:cytology / Q000378:metabolism*; D020411:Oligonucleotide Array Sequence Analysis; D010750:Phosphoproteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D017697:Premenopause; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D034741:RNA, Small Interfering / Q000494:pharmacology; D012097:Repressor Proteins / Q000037:antagonists & inhibitors / Q000235:genetics* / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D017504:Adenovirus E4 Proteins; D047628:Estrogen Receptor alpha; D047629:Estrogen Receptor beta; D004967:Estrogens; D010750:Phosphoproteins; D012333:RNA, Messenger; D034741:RNA, Small Interfering; D012097:Repressor Proteins; C411663:transcription factor p120(E4F)