Accession Number : ADA300386

Title :   Expression and Regulation of the Retinoic Acid Receptor Beta Gene in Human Mammary Epithelial Cells.

Descriptive Note : Annual rept. 22 Aug 94-21 Aug 95,

Corporate Author : WASHINGTON UNIV SEATTLE

Personal Author(s) : Swisshelm, Karen

PDF Url : ADA300386

Report Date : 21 SEP 1995

Pagination or Media Count : 25

Abstract : We have performed BetaRARE gel shift analyses and partial RARB promoter sequence analysis for 4 and 5 breast cancer cell lines, respectively. We have introduced a functional RARBeta gene into four breast cancer cell lines by retroviral vector mediated transduction. We have analyzed 24 differential niRNA transcripts from the cell line, MCF7 cultured in the presence of retinoic acid. We have initiated studies to determine RARB expression in primary tumors. Tumor cells exhibit a dramatically more complex binding to the promoter response element, RARE for all tumor lines tested to date (n=3) compared to normal mammary epithelial cells. We have found 2 mutations in the promoter of the cell line, MDA-MB-23 1. We show that reconstitution of an expressed RARB gene results in dramatic growth suppression of breast cell lines: MCF7 and MDA-MB-23 1, with induction of apoptosis in the MCF7 cells when they are cultured with retinoic acid. Our findings continue to support the hypothesis that the RARB gene product is a candidate tumor suppressor gene for breast cancer.

Descriptors :   *NEOPLASMS, *CANCER, *MAMMARY GLANDS, *BREAST CANCER, GROWTH(GENERAL), SEQUENCES, RESPONSE, SHIFTING, GENES, HYPOTHESES, CELLS(BIOLOGY), GELS, SUPPRESSION, SUPPRESSORS.

Subject Categories : Anatomy and Physiology
      Biology

Distribution Statement : APPROVED FOR PUBLIC RELEASE