Ribonucleotide reductase inhibitor HU acts differently to DFO and 311 as it increases the protein levels of cyclins A, B1, D1, D2, and D3 but has similar action to chelators in terms of increasing cyclin E.

The SK-N-MC neuroepithelioma cell line was incubated for 30 hours at 37°C with DFO (150 μM), 311 (25 μM), or HU (1-300 μM). Western blot analysis was then performed as described in “Materials and methods.” Results shown are representative of 3 separate experiments performed.