Scientists have found that the difference between life and death for some cancer cells hinges on a tiny molecular change - which could one day be harnessed to drive cancer cells to suicide.

Researchers from Oxford University, the University of Texas, and the Genome Institute of Singapore (GIS) at the Agency for Science, Technology and Research (A*Star), found that E2F, a protein which helps control cell growth, can be affected by a process called methylation, where a cluster of carbon and hydrogen atoms latches on to the outside of a gene and makes it harder or easier for that gene to be active.

Depending on where E2F is methylated, it can either cause cells to die off or to proliferate, with what researchers termed "an exquisite level of precision".

Professor Nick La Thangue of the department of oncology at Oxford University, who supervised the project explained: "It's like there's an angel and a devil competing to get on each shoulder of the protein. Which one gets the upper hand is able to whisper in the ear of the protein and tell it what it should do. With the molecular flag on one shoulder, E2F goes into cell kill mode. With the flag on the other, it goes into cell growth mode."

The team suggested that this mechanism could be used for new cancer treatments to push cancer cells to die off.

A*STAR chief scientist Sir David Lane commented: "The detailed study of protein modifications is proving to be a very fertile area for the discovery of effective new targets for cancer drug discovery."