To stop tumor growth, researchers from the University of North Carolina have blocked the main road, which is used by cells to convert sugar into energy. They hoped that this will make the tumor cells "starve" and slow down their growth. To the surprise of researchers, this method has accelerated the growth of laboratory models of medulloblastoma.
The study, published in the journal Cancer Research, is part of the experiments relating to energy production in medulloblastoma, a common malignant brain tumor in children. The results obtained will help scientists to determine the appropriate therapeutic target in the metabolism of sugar and give the key to the mystery of why some cancer cells get their energy from sugar.
"The goal is to understand what makes cancer cells grow, - says Timothy R. Gershon, MD. - To this end, we are continuing to study energy production in cancer cells. "
Previous studies have shown that cancer cells are involved in the process called "aerobic glycolysis," in which oxygen is present, but the cells do not use it to get the maximum amount of energy from sugar. According to Gershon, the cells using aerobic glycolysis, must use more sugar to get the same amount of energy.
"This question scientists first asked in 1920, and we are still trying to find the answer to why cancer cells use aerobic glycolysis," - said Gershon.
Glycolysis produces less power and generates a byproduct known as lactic acid. Normal cells that are replicated in the growing brain, are also involved in aerobic glycolysis.
Although most cells use glycolysis when oxygen is not present, cancer cells use glycolysis all the time. The cause is unknown, but scientists hope that this form of blocking glycolysis becomes a way of cancer treatment.
Scientists from the Laboratory of Gershon blocked the molecular mechanisms that cells use during glycolysis, to prevent the production of energy.
In the new study, the researchers removed the gene that codes for a molecule called pyruvate kinase. Removal of this gene facilitated growth of cancer in laboratory models. "The study shows that some of the steps of glycolysis increased tumor growth, while others decrease," - said Gershon.
Scientists have found a possible clue to why cancer cells use specific way of energy production. Based on their findings, they suggest that medulloblastoma cells use glucose for the production of proteins, which create a greater number of cells, rather than provide them with energy.