Effects of 5-thio-D-glucose on cellular adenosine triphosphate levels and deoxyribonucleic acid rejoining hy hypoxic and aerobic Chinese hamster cells.

Intracellular adenosine triphosphate (ATP) levels were measured in both hypoxic and aerobic cultures of V79 Chinese hamster cells treated with 5-thio-D-glucose (5-SH-D-Glc). This glucose analog, a known inhibitor of D-glucose transport and metabolism, reduced ATP in cell cultures allowed to become hypoxic by cell metabolism, but not in aerobic cultures treated similarly. Cells depleted of ATP were unable to rejoin x-ray-induced deoxyribonucleic acid (DNA) strand breaks as measured by the alkaline surcrose gradient sedimentation technique. Results show that 5-SH-D-Glc leads to reduced energy metabolism in cells dependent on glycolysis for ATP production. The inference for radiation therapy is that inhibition glucose metabolism selectively depletes energy reserves in hypoxic cells, rendering these cells more radiosensitive and leading to a more effective tumor treatment.