02-P021 EDAR signalling in the mammary gland

correlates with recurrence within five years of surgery. To investigate the role of Notch signalling in tumour progression, characterized by increased proliferation, apoptosis resistance, epithelial–mesenchymal transition (EMT) and loss of polarity in 3D cultures, we have created an inducible NICD overexpressing MCF10A cell line. Furthermore, we have various breast cancer cell lines representative of different tumour stages, including DCIS, in which Notch signalling can be blocked by inducible overexpression of Numb/dnMAM. The analysis of both approaches in terms of EMT, polarity and changes in proliferation will help to unravel the mechanism by which Notch contributes to the development of DCIS and the progression to invasive carcinoma. In the long term, this should help to identify new therapeutic treatments for DCIS to prevent the progression to invasive cancer.