Scientists cautious over cancer treatments

York University scientists have discovered a process called methylation, previously thought to drive the development of cancer, occurs in cells that are already cancerous.

The findings mean therapies aimed at reversing this process might not be effective against cancer stem cells, allowing the cancer to return.

The work funded by the charity Yorkshire Cancer Research and the Grand Masonic Charity reveals a major difference between the cells normally treated in cancer and the underlying stem cells.

Davide Pellacani, who led the work in the YCR Cancer Research Unit at the university, said: “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.

“There are obvious differences in the methylation of genes in prostate cancer cells and non-cancer cells. This previously suggested that the process could be driving the progression of cancer, and that this could be reversed by using specific drugs, but our research has suggested that this may not be the case.

“There are clear implications for the effectiveness of new drugs currently being developed to change the methylation pattern in cancers. Only by treating all the cells in a cancer will we approach long-term treatment or even cure.”

The research is published in the journal Cell Death & Differentiation.