"Metformin lowers not only the blood glucose level, but also blocks the respiratory chain in the energy factories of the cell, the mitochondria. The antihypertensive drug syrosingopine inhibits, among other things, the degradation of sugars."

"And the effect was exclusively confined to cancer cells, as the blood cells from healthy donors were insensitive to the treatment."

Syrosingopine sensitizes cancer cells to killing by Metformin Science Advances, published online 23 December 2016 | DOI: 10.1126/sciadv.1601756