Jacqueline Veltmaat obtained her B.Sc. and M.Sc. in Health Sciences at the Maastricht University and furthered her Master’s studies in Molecular Sciences at the Wageningen University (The Netherlands). She worked 1.5 years as a Research Scholar at the Childrens Hospital in Los Angeles (USA) and subsequently pursued her Ph.D. at the Netherlands Institute for Developmental Biology/Hubrecht Laboratory. After having obtained her Ph.D. in 2001, she moved to the Curie Institute in Paris (France), and dedicated her post-doctoral work to the pioneering study of induction and morphogenesis of mammary glands in the mouse embryo. In 2003, she continued this line of research as a Research Associate at The Saban Research Institute of Childrens Hospital in Los Angeles (USA). Jacqueline joined IMCB as a Research Assistant Professor under Prof. J.P. Thiery in October 2006, and with her team and attachment students, continues research on embryonic and postnatal mammary gland development and pathology.

The mammary gland is essential for the survival of mammalian species, as it provides the only -or for humans the healthiest- source of nutrients for the offspring. However, the breast also poses a health threat as it is very susceptible to tumour formation. The molecular mechanisms giving rise to the vast majority of breast tumours still remain elusive due to the complexity of the organ. Over the past decade, it has become increasingly clear that the signalling pathways governing organogenesis are often deregulated in cancers. Indeed, most of the genes that we and others have shown to be indispensable for the induction of mammary gland formation are associated with breast cancer. Therefore, the study of the embryonic phase of mammary gland formation provides us important insights both in the developmental biology of cell fate decision within the surface ectoderm, in particular those leading to breast formation or congenital abnormalities of the breast; as well as in molecular mechanisms relevant to breast cancer.

Mammary glands arise as one of the earliest differentiation events in the surface ectoderm. In a few mammalian species, the development of a ridge in the surface ectoderm on both flanks, spanning from forelimb to hindlimb was demonstrated. Depending on the species, one or several positions on this so called mammary line will proceed to form mammary glands. The various mammalian species differ in the number and positions of their mammary glands. However, mammary glands may not form, or form on aberrant positions on the mammary line when signalling networks are disturbed. Figure 1 shows how differentiation of the surface ectoderm is perturbed when certain genes are knocked out.