Protein linked to cancer
Research in mice has shown how the overexpression (over production) of a small protein allows cancer cells to divide.
Normally, when a cell's DNA is damaged, the cell has mechanisms to recognise this damage and prevent the damaged cell from replicating further. One such mechanism is called the intra-S-phase checkpoint.
In breast and other cancers there is often an over production of a protein called cyclin-dependent kinase subunit (Cks). Until now the link between Cks overexpression and malignancy was unclear.
Now it seems that the Cks protein 'over-rides' the intra-S-phase checkpoint mechanism allowing damaged cells to continue dividing and so become malignant.
This discovery was a lucky observation arising during basic biological research into cell division. The scientists used a chemical known as thymidine to temporarily halt the cell division process, and to artificially synchronise the growth of two different groups of cells – one with normal Cks expression, and the other with Cks overexpression. To the researchers' surprise, the Cks-overexpressing cells failed to stop dividing.
The finding is expected to lead to the targeting of this mechanism with drugs and diagnostic techniques.