- Diabetic drug Metformin, at usual therapeutic doses is too low to be effective against cancer and at higher doses causes unwanted side-effects.
- When used in combination with antihypertensive drug Syrosingopine, the anti-cancer property of diabetic drug gets enhanced
- The effect of the drugs is exclusively confined to cancer cells and does not affect healthy blood cells.
A combination of a diabetes medication and an antihypertensive drug can effectively combat cancer cells.
The team of researchers led by Prof. Michael Hall at the Biozentrum of the University of Basel have also reported that specific cancer cells respond to this combination of drugs.
‘A combination of Metformin and Syrosingopine, is effective in a wide range of cancers including leukemia and liver cancers.’
This drug combination is responsible for programmed "suicide" of cancer cells.
The diabetes drug, Metformin is the most widely prescribed drug for the treatment of type 2 diabetes.
Besides its blood sugar lowering effect, it also displays anti-cancer properties. But its usual therapeutic dose is too low to effectively fight cancer and at higher doses, it can cause unwanted side-effects.
The researchers found the anti-cancer efficacy of metformin gets enhanced when used in combination with antihypertensive drug Syrosingopine.
According to the study the cocktail of these two drugs is effective in a wide range of cancers.
"For example, in samples from leukemia patients, we demonstrated that almost all tumor cells were killed by this cocktail and at doses that are actually not toxic to normal cells", says the first author, Don Benjamin. "And the effect was exclusively confined to cancer cells, as the blood cells from healthy donors were insensitive to the treatment."
How the Drugs Work
Mitochondria are the powerhouses of the cell that convert oxygen and nutrients into adenosine triphosphate (ATP). ATP powers the cell's metabolic activities and this process is called aerobic respiration or cellular respiration. This is how animals breathe.
Cancer cells need high energy due to their increased metabolic activity and rapid growth rate.
Metformin works by works by disrupting the respiratory chain in mitochondria and the antihypertensive drug syrosingopine inhibits the degradation of sugars thus depriving the cell of nutrition.
Thus, the drugs work by interrupting the vital processes which provide energy for the cell.
As a result, the cancer cells are made vulnerable when their energy source gets depleted by using this drug combination.
The researches observed that in mice with liver cancer, the combination therapy, helped to reduce enlargement of the liver and the number of tumor nodules.
Inhibition of the respiratory chain in the mitochondria is a key mechanism. These also reduced cancer cell growth in combination with the antihypertensive drug.
"We have been able to show that the two known drugs lead to more profound effects on cancer cell proliferation than each drug alone," explains Benjamin. "The data from this study support the development of combination approaches for the treatment of cancer patients."
The results of the study have now been published in Science Advances
- Mitochondria - (https://micro.magnet.fsu.edu/cells/mitochondria/mitochondria.html)
- Don Benjamin et al. Syrosingopine sensitizes cancer cells to killing by metformin. Science Advances; (2016) DOI: 10.1126/sciadv.1601756