Prostate cancer drugs ‘not treating root cause’
5 Mar 2014 by Evoluted New Media
New drugs aimed at treating prostate cancer may not be targeting the root cause of the disease say researchers who have discovered that methylation – thought to be a significant driving force behind cancer – occurs in already cancerous cells.
Dr Davide Pellacani from the YCR Cancer Research Unit at the University of York has discovered a major difference between the cells normally treated in cancer, and the underlying ‘stem’ cells.
“To develop cancer, certain proteins found in healthy cells need to be switched off. Sometimes this is caused by methylation – a process where DNA is changed to block instructions for making a specific protein,” said Pellacani.
He added that there are obvious differences in the methylation of genes in prostate cancer cells and non-cancer cells; this previously suggested the process could be driving the progression of cancer and could be reversed using specific drugs. “Our research has suggested that this may not be the case,” Pellacani said.
Prostate cancer is made up of two cell types; rare basal cells including stem cells, from which the tumour is formed; and luminal cells which form the mass of the tumour.
The research team, led by Professor Norman Maitland, has found that the change from basal to luminal cells – a process called differentiation – is strongly linked to methylation differences, suggesting methylation in prostate cancer cells is not a primary driving force for the cancer.
“There are clear implications for the effectiveness of new drugs currently being developed to change the methylation patterns in cancers,” Pellicani said. “At the moment we only treat a proportion of the cells. By breaking the cancer down into its component cell types, we get insights into why cancers come back after treatment. Only by treating all the cells in a cancer will we approach long term treatment or even cure.”
The study – published in Cell Death & Differentiation – builds on previous work by Professor Maitland in 2005 that identified prostate cancer stem cells as the root cause of prostate cancer.
The work was funded by Yorkshire Cancer Research and the Grand Masonic Charity.
