Mnt can serve as a tumour suppressor, as tissue-specific deletion of Mnt in mice resulted in mammary adenocarcinomas and T-cell lymphomas.8, 25, 47 Conversely, Mnt overexpression mimicked Myc knockout, producing growth defects and embryonic lethality25 as well as reducing cell cycle entry and proliferation of MEFs in vitro. Here, MYC is linked to breast adenocarcinoma.