Analysis of ISG15 conjugation (Isgylation)role as driver of poor prognosis in non HER2+ breast cancer tumours. The project includes an analysis of total proteome and ISGylome characterization of MDA-MB-231 cells, wild-type or knock-out for the ISGyltaion associated genes, ISG15, UBE2L6 and USP18. Additionally interactome analysis of the ISGylation target GDI2 was perfored in the same lines.