IDENTIFICATION OF A GENE (GPR30) WITH HOMOLOGY TO THE G-PROTEIN-COUPLED RECEPTOR SUPERFAMILY ASSOCIATED WITH ESTROGEN-RECEPTOR EXPRESSION IN BREAST-CANCER

Using the technique of differential cDNA library screening, a cDNA clo ne was isolated from an estrogen receptor (ER)-positive breast carcino ma cell line (MCF7) cDNA library based upon the overexpression of this gene compared to an ER-negative cell line (MDA-MB-231). Sequence anal ysis of this clone determined that it shared significant homology to G -protein-coupled receptors. This receptor, GPCR-Br, was abundantly exp ressed in the ER-positive breast carcinoma cell lines MCF7, T-47D, and MDA-MB-361. Expression was absent or minimal in the ER-negative breas t carcinoma cell lines BT-20, MDA-MB-231, and HBL-100. GPCR-Br was ubi quitously expressed in human tissues examined but was most abundant in placenta, GPCR-Br expression was examined in 11 primary breast carcin omas, GPCR-Br was detected in all 4 ER-positive tumors and only 1 of 7 ER-negative tumors, Based upon PCR analysis in hybrid cell lines, the gene for GrPCR-Br (HGMW-approved symbol GPR30) was mapped to chromoso me 7p22. The pattern of expression of CPCR-Br indicates that this rece ptor may be involved in physiologic responses specific to hormonally r esponsive tissues. (C) 1997 Academic Press.