The circumstantial evidence is intriguing: as well as being more abundant in tumours than in ordinary cells, vaults, to Dr Scheper's eye, seem to congregate around the vesicles.
Rik Scheper and his colleagues at the Free University of Amsterdam inadvertently stumbled across the major vault protein when they were looking for proteins important in drug resistance in tumour cells.
To both Dr Scheper and Dr Rome, this provides further proof that vaults are shuttles in this case carrying poisons from the nucleus to the vesicles that act as a cell's waste-disposal units.