Link between mitochondria and tumors found

BETHESDA, Md., Oct. 14 (UPI) -- U.S. scientists say they have discovered a link between stem cell potency and the metabolic rate of their mitochondria.

The scientists said they discovered stem cells with more active mitochondria have a greater capacity to differentiate and are more likely to form tumors.

The researchers led by Dr. Toren Finkel at the National Heart, Lung and Blood Institute said they sorted mouse embryonic stem cells by their mitochondrial potential -- the amount of voltage going across mitochondrial membranes, similar to how nerve activity is measured. They found both visually and in the expression of key stem cell markers, low and high metabolism stem cells were indistinguishable.

But, when transplanted into mice, the researchers said the two types of cells had contrasting properties, as cells with lower metabolic rates were more efficient at differentiating into other cell types and the highly metabolic cells were more prone to keep dividing and form teratomas -- tumors characterized by having various tissue types mixed together.

Although the study was conducted with mouse cells, the researchers said they expect a similar relationship to hold true in human stem cells.

The study appears in the Journal of Biological Chemistry.