JERUSALEM, May 20 (Xinhua) -- An international team of researchers has revealed a mechanism for how cells survive at a low sugar state, which holds potential for developing new ways to treat brain cancer, Israel's Ben Gurion University said on Monday.
From humans to bacteria, living organisms need sugar to survive. Cells make fat from sugar and grow. When sugar is low, cells stop making fat or burn themselves out.
Scientists use the term glucose starvation to describe the situation when the sugar levels in a cell drop below the threshold that allows its proper existence.
Cancer cells also feed on sugar to grow. However, they have less sugar as the blood flow to the tumor tissue is weaker than normal tissues, putting cancer cells in a constant state of glucose starvation.
In the new study, researchers from Israel, Germany, and Belgium started their research on how cancer cells can overcome glucose starvation and manage to survive and thrive.
In the study published in Nature Communications, the researchers reported a protein-based mechanism that regulates the rate at which the cell produces fat according to its energy status.
The researchers observed that a protein named 4EBP is produced at higher levels in cancer cells compared to normal tissue. They cultivated human, mouse, and yeast cells with low levels of 4EBP and found that they didn't survive glucose starvation.
Meanwhile, they found that the gene encoding 4EBP is very active in brain tumor cells. The cerebrospinal fluid in the brain contains very little glucose. Therefore, brain tumor cells need to be equipped with such mechanisms to deal with sugar starvation.
The researchers pointed out that the mechanism is exploited by cancer cells, particularly brain cancer cells, to survive in tumor tissue and generate aggressive tumors.
They then muted the expression of 4EBP in brain tumor cells and implanted them into mice brains. The mice implanted with the edited cells presented a higher survival rate than the control group.
The researchers said that the finding holds potential for developing novel treatments for some cancers in the future.
In future studies, they plan to develop a molecule that will block 4EBP, forcing glucose-starved tumor cells to keep making fat and burn themselves out, making it possible to target just the cancer cells and not affect healthy cells in treatments. ■
