1. Department of Cancer Prevention (S.M.K., S.A., R.I.S., R.A.L.), Institute for Cancer Research, Norwegian Radium Hospital,Oslo University Hospital, N-0310 Oslo, Norway
2. Centre for Cancer Biomedicine (S.M.K., S.A., R.I.S., R.A.L.), Faculty of Medicine, University of Oslo, N-0310 Oslo, Norway;
3. Departments of Growth and Reproduction (C.E.H.-H., E.R.-D.M.) Copenhagen University Hospital (Rigshospitalet), DK-2100 Copenhagen, Denmark
4. Paediatrics (C.E.H.-H.), Copenhagen University Hospital (Rigshospitalet), DK-2100 Copenhagen, Denmark
5. Cancer Stem Cell Innovation Center (S.A., R.I.S., R.A.L.), Oslo University Hospital, N-0310 Oslo, Norway;
6. Department of Pathology (V.M.A.), Norwegian Radium Hospital, Oslo University Hospital, N-0310 Oslo, Norway;