18 July Florijn Dekkers receives Veni-grant for breast cancer proposal Back to news She was standing in line loaded with sacks and bags to attend a festival and looked on her telephone to find her e-ticket. A message popped up; a confidential message about the Veni-laureates 2018. Of course she had to look: .. she got it! Just in time for the control, she also found her ticket to enter the festival and had a super-weekend, no doubt. Hubrecht Institute scientist Florijn Dekkers of the Clevers group (co-supervised by Anne Rios of the Princes Maxima center of pediatric oncology) is driven by the fact that breast cancer is difficult to treat because it consists of many different cell types. What causes that diversity, and how to treat it? She will use advanced imaging techniques to visualise illuminated human breast tumours in real time to better understand the pathology of breast cancer. Dekkers plans to use the recently developed breast cancer organoid model to study tumour progression of different breast cancer subtypes. These human tumour organoids will be genetically edited in vitroand then transplanted in vivo(in mice) to track the individual breast cancer cells over time by colouring them. Several methods are used to analyse clones within multi-coloured tumours: First, long-term intravital imaging using a window in the mouse which allows us to study the shrinkage or expansion (dynamics) of the clones in real time. Second, 3D imaging of fixed tumours to compare cell types present in different clones within a tumour or between different tumours. And third, single-cell RNA sequencing to characterize the molecular profile of different clones. The next stage of her proposal, using the same mice, consists of doing research on metastases. The coloured primary tumour, named confetti-tumour because of the colouring of the different cell types, will be removed, leaving only coloured metastases. Here Dekkers is interested in how different cell types contribute to metastases; one cell, more cells? And more important even, what are the molecular mechanisms that contribute to metastases formation? We will hear more from Florijn Dekkers. This is not the first grant she’s got and it will definitely not be the last if we can help it.