Accession Number : ADA337595

Title :   WNT-Signals and the Regulation of Normal and Cancerous Growth in the Mammary Gland.

Descriptive Note : Annual rept. 15 Sep 96-14 Sep 97

Corporate Author : HARVARD UNIV CAMBRIDGE MA

Personal Author(s) : McMahon, Andrew P.

PDF Url : ADA337595

Report Date : OCT 1997

Pagination or Media Count : 19

Abstract : Wnt genes encode a large family of secreted signaling molecules related to the Drosophila pattern regulating gene wingless. Several members of the Wnt family are implicated in mammary tumorigenesis suggesting that Wnt-activated pathways are a normal component of mammary gland development. Consistent with this hypothesis, we have demonstrated that seven Wnt genes are expressed in the developing mammary gland. One of these, Wnt-7a, appears to be required for epithelial branching in the adult mammary gland. In contrast, Wnt-6, Wnt-lOa and Wnt-lOb, are expressed at the earliest stages suggesting roles in induction and growth of the embryonic mammary gland. Recent evidence indicates that Frizzled members encode Wnt-receptors, and that Lef-l and Lmx-lb are transcriptional mediators of Wnt-signaling. In this regard we have demonstrated that Fz-6 is expressed in the embryonic mammary gland, consistent with transducing Wnt signals, and nmx-lb, like Lef-l, is required for mammary gland development. We are using a combination of transplantation and transgenic procedures to further explore these pathways. Our hope is that a better understanding of normal development of the mammary gland will provide new insights into possible mechanisms underlying tumor formation.

Descriptors :   *GENES, *MAMMARY GLANDS, *GROWTH(PHYSIOLOGY), *BREAST CANCER, MOLECULES, NEOPLASMS, SIGNALS, PATTERNS, HYPOTHESES, EMBRYOS, ADULTS, TRANSPLANTATION, CANCER, DROSOPHILA.

Subject Categories : Genetic Engineering and Molecular Biology
      Anatomy and Physiology

Distribution Statement : APPROVED FOR PUBLIC RELEASE