Hypermethylation of HpaII recognition sequences within the 5' coding region of the estrogen receptor gene is not associated with estrogen receptor negativity in primary breast tumours.
Estrogen receptor negative tumours are unable to respond to antiestrogen therapy. The underlying molecular mechanisms of estrogen receptor negativity are poorly understood. Cytosine mechylation is one of the mechanisms of gene control and previous studies, particularly on breast tumour derived cell lines have suggested that hypermethylation of HpaII recognition sequences within the 5' coding region of estrogen receptor may be responsible for gene inactivity. This study has examined the methylation status of HpaII recognition sequences in estrogen receptor positive and negative breast tumours taking into account a polymorphic HpaII site in the 5' coding region of the estrogen receptor gene. It is concluded that hypermethylation of one or more of the 4 or 5 HpaII recognition sequences in the 5' coding region of estrogen receptor is not associated with ER negativity in primary breast tumours.
Department of Pathology, University of Western Australia, Nedlands, Australia.
P H
PH
Kay
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R
Hähnel
H
H
Gunn
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Harmon
J
J
Song
D000230:Adenocarcinoma / Q000235:genetics* / Q000473:pathology*; D001943:Breast Neoplasms / Q000235:genetics* / Q000473:pathology*; D019175:DNA Methylation; D004273:DNA, Neoplasm / Q000737:chemistry / Q000378:metabolism; D015257:DNA-Cytosine Methylases / Q000378:metabolism*; D005260:Female; D005838:Genotype; D006801:Humans; D016133:Polymerase Chain Reaction; D011960:Receptors, Estrogen / Q000032:analysis / Q000096:biosynthesis / Q000235:genetics*; D013379:Substrate Specificity
D004273:DNA, Neoplasm; D011960:Receptors, Estrogen; C029641:DNA modification methylase HpaII; D015257:DNA-Cytosine Methylases