A protein that aids the survival of cancer-causing stem cells is described in Nature. The study boosts our understanding of leukaemia and may help the development of new anti-cancer therapies.
Leukaemias are fuelled by rogue cancer stem cells that can divide asymmetrically to produce more cancer stem cells and other more specialized cancerous cells. Pier Giuseppe Pelicci and colleagues show that leukaemia-associated oncogenes trigger DNA damage in blood stem cells. The cell cycle inhibitor p21 is then upregulated, temporarily preventing the cancer stem cells from proliferating and giving them time to repair the damage. This means the same cancer stem cells can, in theory, go on to reseed the cancer.
Most cancer therapies focus on killing rapidly dividing cancer cells, and are not designed to kill any quiescent or slowly dividing cancer stem cells that may exist. The study indicates that p21 could be a viable anti-cancer target. If the p21-dependent DNA repair is blocked, the slowly proliferating leukaemia stem cells should eventually become exhausted and die.
Pier Giuseppe Pelicci (Istituto Europeo di Oncologia, Milan, Italy)
(C) Nature press release.
Message posted by: Trevor M. D'Souza