Cloning of estrogen-regulated messenger RNA sequences from human breast cancer cells.
A complementary DNA library was constructed from RNA of estrogen-stimulated MCF-7 cells and screened for estrogen-regulated sequences. Four different messenger RNA sequences of varying abundance were isolated. Two of the sequences (pNR-3 and pNR-4) were induced approximately 2-fold, while the other two (pNR-1 and pNR-2) were induced at least 8-fold. The induction of both pNR-1 and pNR-2 requires similar physiological concentrations of estradiol and is near maximal at 10(-10) M. An increase in the levels of the RNAs is seen after 30 min of estrogen treatment, but pNR-1 reaches its maximal concentration faster than pNR-2. pNR-1 and pNR-2 were not expressed in all human breast cancer cell lines tested. pNR-1 was expressed and regulated by estrogen in the estrogen receptor-positive cell lines, MCF-7, T-47D, and ZR 75, whereas pNR-2 was not expressed in the T-47D cell line. pNR-1 and pNR-2 were not detected in two estrogen receptor-negative cell lines (BT20 and HBL 100). As the proliferation of the MCF-7, T47D, and ZR 75 cell lines is stimulated by estradiol, pNR-1 may provide a useful marker of hormone-responsive breast cancer.
D001483:Base Sequence; D001943:Breast Neoplasms / Q000235:genetics*; D002478:Cells, Cultured; D003001:Cloning, Molecular; D004967:Estrogens / Q000494:pharmacology*; D005260:Female; D005786:Gene Expression Regulation / Q000187:drug effects; D006801:Humans; D009693:Nucleic Acid Hybridization; D011061:Poly A / Q000032:analysis; D012313:RNA / Q000032:analysis; D012333:RNA, Messenger / Q000032:analysis*
D004967:Estrogens; D012333:RNA, Messenger; D011061:Poly A; D012313:RNA