1. Molecular Oncology Group, Portuguese Institute of Oncology, 4200-072 Porto Centre, Portugal; Department of Biology, University of Aveiro, 3810-193 Aveiro, Portugal; ICBAS, Abel Salazar Biomedical Sciences Institute, University of Porto, 4099-003 Porto, Portugal; Medical Oncology Department, Portuguese Institute of Oncology, 4200-072 Porto Centre, Portugal; and Virology Department, Portuguese Institute of Oncology, 4200-072 Porto Centre, Portugal