Subsequent development occurs during sexual maturation and during pregnancy and lactation.
In this review, we will address the beginnings of this process, the formation of the rudimentary gland in embryos. In development, I am not that different from a mouse or a fly and many of the signals that regulate development are used time and time again. Many more details require further elucidation, but there also remain many relatively untouched questions. Therefore, the mechanisms by which these signaling pathways regulate embryonic morphogenesis may inform how they might contribute to tumor growth and metastases. Last decades revealed the close control of myosin-II-dependent biomechanical morphogenesis by patterning gene expression, with constant progress in the understanding of the underlying molecular mechanisms. Thus Wnt10b and Lef1 become elevated along the mammary line in a punctate fashion that mirrors the positions of the underlying somites.
We are also just beginning to understand which signaling pathways contribute to the initiation of ductal development. (3) What distinguishes mammary buds from other embryonic skin appendages? During embryonic development, breast cells proliferate, migrate, and invade from one stromal compartment into another. Tbx3 is constrained by antagonism from ventral Bmp4. This knowledge is then utilized in the rational design of therapeutic strategies. During normal development, these pathways must be constrained so that morphogenesis is coordinated properly. Key stages of mammary gland development: Molecular mechanisms involved in the formation of the embryonic mammary gland. Interestingly, both snail and slug have been shown to be expressed in the epithelial cells of the embryonic mammary bud. Signaling pathways such as the Wnt, Hedgehog, FGF, EGF, IGF-1, and PTHrP systems discussed in this review have all been implicated in the pathogenesis of metastatic breast cancer. These are just a few of the many interesting problems that remain to be tackled to better understand the initial development of the mammary gland. (4) What controls the development of the mammary fat pad and how do adipocytes change the nature of ductal morphogenesis? Although one could envision that embryonic mammary epithelial cells might undergo an EMT during the formation of the mammary placode or during the outgrowth of the mammary sprout, this issue has not been examined in detail in the developing embryonic gland.Additional Perspectives on Mammary Gland Biology available at www.cshperspectives.orgThe mammary gland is a specialized epidermal appendage, whose development begins during embryogenesis but is not fully completed until the beginning of lactation. In this review, we outline the distinct stages of embryonic mammary development and discuss the molecular pathways involved in the regulation of morphogenesis at each stage. Breast Cancer Res 7: 220–224 [ PMC free article ] [ PubMed ] Hens J, Dann P, Hiremath M, Pan TC, Chodosh L, Wysolmerski J 2009.
This page is a link to many different resources related to molecular development.