It is now believed that luminal progenitor cells – the ‘daughters’ of breast stem cells – are the likely source of basal-like breast tumors that develop in women carrying mutations in the gene BRCA1. This discovery was made by a team led by Associate Professors Jane Visvader and Geoff Lindeman (couple of other authors' publications: 1,2,3,4; reviews: 1,2)  of the Walter and Eliza Hall Institute’s Victorian Breast Cancer Research Consortium Laboratory, and was published in today’s issue of the journal Nature Medicine. Dr. Visvader indicated that in recent years it has been believed that the breast stem cells are what give rise to BRCA1 tumors. Yet breast tissue from women with BRCA1 mutations has been found to have an unexpectedly high number of luminal progenitor cells, as seen in the research conducted by Dr. Elgene Lim and Dr. François Vaillant at the institute. After the gene expression studies revealed BRCA1 breast tissue and basal breast tumors to be more similar to normal luminal progenitor cells than any other cell type in the breast, focus has shifted away from breast stem cells to errant luminal progenitors.

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