In new research that appeared in the journal Cell Reports, scientists have found that two drugs currently used in the treatment of diabetes and hypertension may be helpful to people with cancer.
A drug cocktail comprising metformin and syrosingopine was shown in the new study to be potentially useful for killing off cancer cells.
The investigation, which was apparently aimed at advancing earlier findings, is a result of collaboration between Biozentrum and Basilea Pharmaceutica International Ltd.
Metformin as a potential cancer treatment
This was not the first study to hint at the potential of metformin for dealing with cancer cells. The popular type 2 diabetes medication had been shown in earlier research as being possibly useful for battling tumors in the body.
Cancer is just one of several conditions that scientists have observed this drug may help with. It is also thought capable of boosting fertility, regulating menstrual cycles and enhancing longevity.
Researchers at University of Basel’s Biozentrum had found in a previous study that metformin can kill cancer cells when combined with a medication for treating blood pressure issues.
The study published recently aimed to find out how this was possible – the mechanism behind the observed effect.
Starving cancer cells
While it had been previously revealed that metformin may help against cancer, the usual dose for diabetes is known to not be sufficient to achieve this. Researchers in the current study, therefore, used a cocktail featuring metformin and the antihypertensive drug syrosingopine for this purpose.
They found that these medications combined to deprive cancer cells of needed energy, causing them to die. The drugs inhibited the regeneration of NAD+, a molecule cancer cells depend on for constant supply of energy they need to grow and multiply rapidly.
These medications basically blocked the cellular pathways that are used for regenerating NAD+.
“We have now discovered that syrosingopine efficiently blocks the two most important lactate transporters and thus, inhibits lactate export,” first study author Don Benjamin explained. “Higher intracellular lactate concentrations, in turn, prevent NADH from being recycled into NAD+.”
Cancer cells depend on the metabolic pathway that converts glucose to lactate. But too much lactate can block the glycolytic pathway they depend on for energy. Therefore, they get rid of excess lactate through the use of specific transporters.
This is where syrosingopine comes in to help. It assists in blocking that pathway.
Metformin, on the other hand, helps to block the second of the two cellular pathways that cancer cells depend on for NAD+ regeneration.
When the level of that molecule drops, it is only a matter of time before the cells start to die.
The researchers believed this drug cocktail offers a promising remedy to the dreaded medical condition. Combination of drugs similar in action to syrosingopine with metformin can improve the potential of the anti-diabetic medication for treating cancer.
The finding on the action of syrosingopine as a dual inhibitor of two key lactate transporters is a very significant one. There are no other inhibitors available for one of the two transporters at the moment.