Methylation of the estrogen receptor-α gene promoter is selectively increased in proliferating human aortic smooth muscle cells

Anita K. Ying, Hamdy H. Hassanain, Christine M. Roos, Dominic J. Smiraglia, Jean Pierre J Issa, Robert E. Michler, Michael Caligiuri, Christoph Plass, Pascal J. Goldschmidt-Clermont

Research output: Contribution to journalArticle

98 Citations (Scopus)

Abstract

Objective: Atherosclerosis is a multigenic process leading to the progressive occlusion of arteries of mid to large caliber. A key step of the atherogenic process is the proliferation and migration of vascular smooth muscle cells into the intimal layer of the arterial conduit. The phenotype of smooth muscle cells, once within the intima, is known to switch from contractile to de-differentiated, yet the regulation of this switch at the genomic level is unknown. Estrogen has been shown to regulate cell proliferation both for cancer cells and for vascular cells. However, methylation of the estrogen receptor-α gene (ERα) promoter blocks the expression of ERα, and thereby can antagonize the regulatory effect of estrogen on cell proliferation. We sought to determine whether methylation of the ERα is differentially and selectively regulated in contractile versus de-differentiated arterial smooth muscle cells. Methods: We used Southern blot assay, combined bisulfite restriction analysis (Cobra) and restriction landmark genome scanning (RLGS-M) to determine the methylation status of ERα in human aortic smooth muscle cells, either in situ (normal aortic tissue, contractile phenotype), or the same cells explanted from the aorta and cultured in vitro (de-differentiated phenotype). Results: We provide evidence that methylation of the ERα in smooth muscle cells that display a proliferative phenotype is altered relative to the same cells studied within the media of non-atherosclerotic aortas. Thus, the ERα promoter does not appear to be methylated in situ (normal aorta), but becomes methylated in proliferating aortic smooth muscle cells. Using a screening technique, RLGS- M, we show that alteration in methylation associated with the smooth muscle cell phenotypic switch does not seem to require heightened activity of the methyltransferase enzyme, and appears to be selective for the ERα and a limited pool of genes whose CpG island becomes either demethylated or de novo methylated. Conclusions: Our data support the concept that the genome of aortic smooth muscle cells is responsive to environmental conditions, and that DNA methylation, in particular methylation of the ERα, could contribute to the switch in phenotype observed in these cells. (C) 2000 Elsevier Science B.V.

Original languageEnglish (US)
Pages (from-to)172-179
Number of pages8
JournalCardiovascular Research
Volume46
Issue number1
DOIs
StatePublished - Apr 2000
Externally publishedYes

Fingerprint

Estrogen Receptors
Methylation
Smooth Muscle Myocytes
Genes
Phenotype
Aorta
Estrogens
Cell Proliferation
Genome
Tunica Intima
Gene Pool
CpG Islands
Methyltransferases
DNA Methylation
Southern Blotting
Vascular Smooth Muscle
Blood Vessels
Atherosclerosis
Arteries
Enzymes

Keywords

  • Artherosclerosis
  • Receptors
  • Smooth muscle

ASJC Scopus subject areas

  • Cardiology and Cardiovascular Medicine

Cite this

Methylation of the estrogen receptor-α gene promoter is selectively increased in proliferating human aortic smooth muscle cells. / Ying, Anita K.; Hassanain, Hamdy H.; Roos, Christine M.; Smiraglia, Dominic J.; Issa, Jean Pierre J; Michler, Robert E.; Caligiuri, Michael; Plass, Christoph; Goldschmidt-Clermont, Pascal J.

In: Cardiovascular Research, Vol. 46, No. 1, 04.2000, p. 172-179.

Research output: Contribution to journalArticle

Ying, AK, Hassanain, HH, Roos, CM, Smiraglia, DJ, Issa, JPJ, Michler, RE, Caligiuri, M, Plass, C & Goldschmidt-Clermont, PJ 2000, 'Methylation of the estrogen receptor-α gene promoter is selectively increased in proliferating human aortic smooth muscle cells', Cardiovascular Research, vol. 46, no. 1, pp. 172-179. https://doi.org/10.1016/S0008-6363(00)00004-3
Ying, Anita K. ; Hassanain, Hamdy H. ; Roos, Christine M. ; Smiraglia, Dominic J. ; Issa, Jean Pierre J ; Michler, Robert E. ; Caligiuri, Michael ; Plass, Christoph ; Goldschmidt-Clermont, Pascal J. / Methylation of the estrogen receptor-α gene promoter is selectively increased in proliferating human aortic smooth muscle cells. In: Cardiovascular Research. 2000 ; Vol. 46, No. 1. pp. 172-179.
@article{aeafafdbf19e40e9b4f2d1b8ac6ba2c2,
title = "Methylation of the estrogen receptor-α gene promoter is selectively increased in proliferating human aortic smooth muscle cells",
abstract = "Objective: Atherosclerosis is a multigenic process leading to the progressive occlusion of arteries of mid to large caliber. A key step of the atherogenic process is the proliferation and migration of vascular smooth muscle cells into the intimal layer of the arterial conduit. The phenotype of smooth muscle cells, once within the intima, is known to switch from contractile to de-differentiated, yet the regulation of this switch at the genomic level is unknown. Estrogen has been shown to regulate cell proliferation both for cancer cells and for vascular cells. However, methylation of the estrogen receptor-α gene (ERα) promoter blocks the expression of ERα, and thereby can antagonize the regulatory effect of estrogen on cell proliferation. We sought to determine whether methylation of the ERα is differentially and selectively regulated in contractile versus de-differentiated arterial smooth muscle cells. Methods: We used Southern blot assay, combined bisulfite restriction analysis (Cobra) and restriction landmark genome scanning (RLGS-M) to determine the methylation status of ERα in human aortic smooth muscle cells, either in situ (normal aortic tissue, contractile phenotype), or the same cells explanted from the aorta and cultured in vitro (de-differentiated phenotype). Results: We provide evidence that methylation of the ERα in smooth muscle cells that display a proliferative phenotype is altered relative to the same cells studied within the media of non-atherosclerotic aortas. Thus, the ERα promoter does not appear to be methylated in situ (normal aorta), but becomes methylated in proliferating aortic smooth muscle cells. Using a screening technique, RLGS- M, we show that alteration in methylation associated with the smooth muscle cell phenotypic switch does not seem to require heightened activity of the methyltransferase enzyme, and appears to be selective for the ERα and a limited pool of genes whose CpG island becomes either demethylated or de novo methylated. Conclusions: Our data support the concept that the genome of aortic smooth muscle cells is responsive to environmental conditions, and that DNA methylation, in particular methylation of the ERα, could contribute to the switch in phenotype observed in these cells. (C) 2000 Elsevier Science B.V.",
keywords = "Artherosclerosis, Receptors, Smooth muscle",
author = "Ying, {Anita K.} and Hassanain, {Hamdy H.} and Roos, {Christine M.} and Smiraglia, {Dominic J.} and Issa, {Jean Pierre J} and Michler, {Robert E.} and Michael Caligiuri and Christoph Plass and Goldschmidt-Clermont, {Pascal J.}",
year = "2000",
month = "4",
doi = "10.1016/S0008-6363(00)00004-3",
language = "English (US)",
volume = "46",
pages = "172--179",
journal = "Cardiovascular Research",
issn = "0008-6363",
publisher = "Oxford University Press",
number = "1",

}

TY - JOUR

T1 - Methylation of the estrogen receptor-α gene promoter is selectively increased in proliferating human aortic smooth muscle cells

AU - Ying, Anita K.

AU - Hassanain, Hamdy H.

AU - Roos, Christine M.

AU - Smiraglia, Dominic J.

AU - Issa, Jean Pierre J

AU - Michler, Robert E.

AU - Caligiuri, Michael

AU - Plass, Christoph

AU - Goldschmidt-Clermont, Pascal J.

PY - 2000/4

Y1 - 2000/4

N2 - Objective: Atherosclerosis is a multigenic process leading to the progressive occlusion of arteries of mid to large caliber. A key step of the atherogenic process is the proliferation and migration of vascular smooth muscle cells into the intimal layer of the arterial conduit. The phenotype of smooth muscle cells, once within the intima, is known to switch from contractile to de-differentiated, yet the regulation of this switch at the genomic level is unknown. Estrogen has been shown to regulate cell proliferation both for cancer cells and for vascular cells. However, methylation of the estrogen receptor-α gene (ERα) promoter blocks the expression of ERα, and thereby can antagonize the regulatory effect of estrogen on cell proliferation. We sought to determine whether methylation of the ERα is differentially and selectively regulated in contractile versus de-differentiated arterial smooth muscle cells. Methods: We used Southern blot assay, combined bisulfite restriction analysis (Cobra) and restriction landmark genome scanning (RLGS-M) to determine the methylation status of ERα in human aortic smooth muscle cells, either in situ (normal aortic tissue, contractile phenotype), or the same cells explanted from the aorta and cultured in vitro (de-differentiated phenotype). Results: We provide evidence that methylation of the ERα in smooth muscle cells that display a proliferative phenotype is altered relative to the same cells studied within the media of non-atherosclerotic aortas. Thus, the ERα promoter does not appear to be methylated in situ (normal aorta), but becomes methylated in proliferating aortic smooth muscle cells. Using a screening technique, RLGS- M, we show that alteration in methylation associated with the smooth muscle cell phenotypic switch does not seem to require heightened activity of the methyltransferase enzyme, and appears to be selective for the ERα and a limited pool of genes whose CpG island becomes either demethylated or de novo methylated. Conclusions: Our data support the concept that the genome of aortic smooth muscle cells is responsive to environmental conditions, and that DNA methylation, in particular methylation of the ERα, could contribute to the switch in phenotype observed in these cells. (C) 2000 Elsevier Science B.V.

AB - Objective: Atherosclerosis is a multigenic process leading to the progressive occlusion of arteries of mid to large caliber. A key step of the atherogenic process is the proliferation and migration of vascular smooth muscle cells into the intimal layer of the arterial conduit. The phenotype of smooth muscle cells, once within the intima, is known to switch from contractile to de-differentiated, yet the regulation of this switch at the genomic level is unknown. Estrogen has been shown to regulate cell proliferation both for cancer cells and for vascular cells. However, methylation of the estrogen receptor-α gene (ERα) promoter blocks the expression of ERα, and thereby can antagonize the regulatory effect of estrogen on cell proliferation. We sought to determine whether methylation of the ERα is differentially and selectively regulated in contractile versus de-differentiated arterial smooth muscle cells. Methods: We used Southern blot assay, combined bisulfite restriction analysis (Cobra) and restriction landmark genome scanning (RLGS-M) to determine the methylation status of ERα in human aortic smooth muscle cells, either in situ (normal aortic tissue, contractile phenotype), or the same cells explanted from the aorta and cultured in vitro (de-differentiated phenotype). Results: We provide evidence that methylation of the ERα in smooth muscle cells that display a proliferative phenotype is altered relative to the same cells studied within the media of non-atherosclerotic aortas. Thus, the ERα promoter does not appear to be methylated in situ (normal aorta), but becomes methylated in proliferating aortic smooth muscle cells. Using a screening technique, RLGS- M, we show that alteration in methylation associated with the smooth muscle cell phenotypic switch does not seem to require heightened activity of the methyltransferase enzyme, and appears to be selective for the ERα and a limited pool of genes whose CpG island becomes either demethylated or de novo methylated. Conclusions: Our data support the concept that the genome of aortic smooth muscle cells is responsive to environmental conditions, and that DNA methylation, in particular methylation of the ERα, could contribute to the switch in phenotype observed in these cells. (C) 2000 Elsevier Science B.V.

KW - Artherosclerosis

KW - Receptors

KW - Smooth muscle

UR - http://www.scopus.com/inward/record.url?scp=0034060168&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0034060168&partnerID=8YFLogxK

U2 - 10.1016/S0008-6363(00)00004-3

DO - 10.1016/S0008-6363(00)00004-3

M3 - Article

C2 - 10727665

AN - SCOPUS:0034060168

VL - 46

SP - 172

EP - 179

JO - Cardiovascular Research

JF - Cardiovascular Research

SN - 0008-6363

IS - 1

ER -