PMID- 9541193 OWN - NLM STAT- MEDLINE DCOM- 19980526 LR - 20190905 IS - 0167-6806 (Print) IS - 0167-6806 (Linking) VI - 48 IP - 1 DP - 1998 Mar TI - Predictive value of SRC-1 for tamoxifen response of recurrent breast cancer. PG - 87-92 AB - Tamoxifen causes an objective response in about one-third of metastatic breast cancer and in only half of the breast cancer patients with estrogen receptor (ER) positive tumors. Steroid-receptor coactivator-1 (SRC-1) appears to be a general coactivator for steroid receptors and rate limiting factor necessary for efficient ER transactivation. We aimed to evaluate whether SRC-1 expression is an additional factor for prediction of response to first-line tamoxifen therapy in patients who developed recurrent disease. Here for the first time, we report on SRC-1 expression using a semi-quantitative RT-PCR in 21 primary breast tumors, seven mammary tumor cell-lines, 12 fibroblast cultures, and six normal breast tissues. The highest levels of SRC-1 were observed in normal tissues, intermediate levels in tumor tissues, and the lowest levels in breast tumor cell-lines. There was no relationship between the levels of SRC-1 in these primary tumors and the proportion of tumor cells within the surgical samples, nor with ER status. The median SRC-1 level was, however, lower in tumors from patients that did not respond to tamoxifen. Our findings suggest that high levels of SRC-1 indicate a favorable response to tamoxifen of patients with recurrent breast cancer. FAU - Berns, E M AU - Berns EM AD - Department of Medical Oncology, Rotterdam Cancer Institute (Daniel den Hoed Kliniek)/University Hospital Rotterdam, The Netherlands. berns@bidh.azr.nl FAU - van Staveren, I L AU - van Staveren IL FAU - Klijn, J G AU - Klijn JG FAU - Foekens, J A AU - Foekens JA LA - eng PT - Comparative Study PT - Journal Article PT - Research Support, Non-U.S. Gov't PL - Netherlands TA - Breast Cancer Res Treat JT - Breast cancer research and treatment JID - 8111104 RN - 0 (Antineoplastic Agents, Hormonal) RN - 0 (Receptors, Steroid) RN - 0 (Transcription Factors) RN - 094ZI81Y45 (Tamoxifen) RN - EC 2.3.1.48 (Histone Acetyltransferases) RN - EC 2.3.1.48 (NCOA1 protein, human) RN - EC 2.3.1.48 (Nuclear Receptor Coactivator 1) SB - IM MH - Adult MH - Aged MH - Aged, 80 and over MH - Antineoplastic Agents, Hormonal/*therapeutic use MH - Breast Neoplasms/*drug therapy/metabolism MH - Female MH - Histone Acetyltransferases MH - Humans MH - Middle Aged MH - Neoplasm Recurrence, Local/drug therapy MH - Nuclear Receptor Coactivator 1 MH - Prognosis MH - Receptors, Steroid/analysis MH - Tamoxifen/*therapeutic use MH - Transcription Factors/*analysis MH - Tumor Cells, Cultured EDAT- 1998/04/16 00:00 MHDA- 1998/04/16 00:01 CRDT- 1998/04/16 00:00 PHST- 1998/04/16 00:00 [pubmed] PHST- 1998/04/16 00:01 [medline] PHST- 1998/04/16 00:00 [entrez] AID - 10.1023/a:1005903226483 [doi] PST - ppublish SO - Breast Cancer Res Treat. 1998 Mar;48(1):87-92. doi: 10.1023/a:1005903226483.