Oestrogen regulates oestrogen receptor mRNA levels in an oestrogen-responsive human breast cancer cell line.
The EFM-19 human breast cancer cell line contains high levels of oestrogen receptor mRNA and is oestrogen responsive for growth. The oestrogen receptor gene appears to be specifically regulated by oestrogens in EFM-19 cells. The induction by oestradiol is half-maximal in the presence of 3 x 10(-11) M oestradiol. LY117018 is a potent antioestrogen with a similar affinity to oestradiol for the oestrogen receptor. LY117018 completely blocks the induction of the oestrogen receptor mRNA by oestradiol when it is present in a 50-fold molar excess. The ability of oestrogens to control the levels of their own receptor in human breast cancer cells has implications for the understanding of oestrogen responsiveness and the amelioration of endocrine therapy.
Westley
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BR
University Department of Pathology, Royal Victoria Infirmary, Newcastle upon Tyne, United Kingdom.
May
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FE
D001943:Breast Neoplasms / Q000235:genetics*; D002460:Cell Line; D004958:Estradiol / Q000494:pharmacology*; D005260:Female; D006801:Humans; D011759:Pyrrolidines / Q000494:pharmacology; D012333:RNA, Messenger / Q000378:metabolism*; D011960:Receptors, Estrogen / Q000235:genetics*; D013876:Thiophenes / Q000494:pharmacology
D011759:Pyrrolidines; D012333:RNA, Messenger; D011960:Receptors, Estrogen; D013876:Thiophenes; D004958:Estradiol; C025430:LY 117018