Breast Development

Our research focuses on the initial development of the mammary primordium to determine how undifferentiated tissue is directed to form the mammary gland. The cellular processes that are defective in cancer are in large part those that regulate organ development during embryogenesis. We study early embryonic mammary development to gain a fundamental understanding of the genetic state of the most primitive mammary cells, their interactions, and native functions, to provide insight into the regulation of the processes that occur as the mammary primordium forms (cell adhesion modulation, cell migration, stem cell delimitation, progenitor proliferation, lineage commitment).

A key aspect of organogenesis of the mammary primordium is the formation of tissue-specific stem cells which arise as a result of a sequence of developmental decisions that we are trying to understand due to their relevance to breast cancer. The initial stages of primordial formation is a critical phase of mammary development when mammary cell fate is acquired and tissue-specific stem cell populations are delimited. Mammary primordial cells harbour repopulating activity, reflecting their capacity for self-renewal, a hallmark of stem cells. It is thought that pathways that govern stem cell function are often subverted in breast and other types of cancer. We have been analysing the earliest populations of mammary cells present in the mammary primordium to learn more about their molecular identities and behavioral properties. We aim to elucidate the signalling pathways regulating self-renewal and mammary epithelial differentiation. Our ultimate aim is to identify regulatory stem cell networks active in breast cancer that promote self-renewal versus differentiation.