Chemosensitizing and cytotoxic effects of 2-deoxy-D-glucose on breast cancer cells.

BACKGROUND

Accelerated glucose uptake for anaerobic glycolysis is one of the major metabolic changes found in malignant cells. This property has been exploited for imaging malignancies and as a possible anticancer therapy. The nonmetabolizable glucose analog 2-deoxyglucose (2 DG) interferes with glucose metabolism leading to breast cancer cell death.

AIMS

To determine whether 2DG can synergize with chemotherapeutic agents commonly used in breast cancer treatment and identify cellular characteristics associated with sensitivity to 2DG.

MATERIALS AND METHODS

SkBr3 breast cancer cells were incubated with varying concentrations of 5-fluorouracil (5FU), doxorubicin, cisplatin, cyclophosphamide, or herceptin with or without 2DG. Cell viability was measured using the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay.

RESULTS

Combining 2DG with doxorubicin, 5 FU, cyclophosphamide, and herceptin resulted in enhanced cell death compared with each agent alone, while in combination with cisplatin, the amount of cell death was additive. Mouse embryo fibroblasts (MEF) mutated for p53 (-/-) were 30% more sensitive to the cytotoxic effects of 2DG than the parental cell lines. Cells mutated for Bax/Bac, genes involved in protection from apoptosis, are slightly more sensitive than the parental cell lines.

CONCLUSIONS

These results indicate that 2DG acts synergistically with specific chemotherapeutic agents in causing cell death and the class of chemicals most sensitive appear to be those which cause DNA damage.