Gene switch that can 'turn off' cancer identified

Scientists have identified genetic switches that can be 'turned off' to stop the growth of cancer cells, an advance that paves the way for new therapies against the deadly disease.
Researchers from Karolinska Institutet in Sweden found that cancer cells and normal cells use different gene switches in order to regulate cell growth.
The removal of a large regulatory region linked to different types of cancer caused a dramatic resistance to tumour formation, but did not affect normal cell growth in mice, researchers found.
"Since we find that the growth of normal and cancer cells is driven by different gene switches, we can in principle aim at switching off the system for growth only in the cancer cells without any harmful effect on the growth of normal cells," said Jussi Taipale, professor at Karolinska Institutet.

"This can lead to the development of highly specific approaches for cancer therapy with much lower toxic side effects," Taipale said.
Researchers analysed a large gene switch region that is linked to the risks of developing many different types of cancer, including prostate, breast, colon, bladder and thyroid cancers as well as chronic lymphocytic leukaemia and myeloma.

The variation in this region accounts for far more cancer-related deaths than inherited mutations in well-known cancer-causing genes, researchers said.
They turned the gene switches off by removing this region from the mouse genome, and found that its loss has no effect on normal mouse development and growth.

However, they found that the mice were strongly resistant to the formation of breast tumours and tumours in the intestine.
The results show that normal cells can function and divide without the genetic elements that are needed for the growth of cancer cells.
The study highlights the possibility of developing highly specific cancer drugs, researcher said.
The study was published in the journal eLife.