Highly glycolytic
cervical cancers largely resist treatment by
cisplatin and coadministered pelvic irradiation as the present standard of care. In this study, we investigated the effects of inhibiting glycolysis and
thiol redox metabolism to evaluate them as alternate treatment strategies in these
cancers. In a panel of multiple
cervical cancer cell lines, we evaluated sensitivity to inhibition of glycolysis (2-deoxyglucose, 2-DG) with or without simultaneous inhibition of
glutathione and
thioredoxin metabolism (BSO/AUR). Intracellular levels of total and
oxidized glutathione,
thioredoxin reductase activity, and indirect measures of intracellular
reactive oxygen species were compared before and
after treatment. Highly radioresistant cells were the most sensitive to 2-DG, whereas intermediate radioresistant cells were sensitive to 2-DG plus BSO/AUR. In response to 2-DG/BSO/AUR treatment, we observed increased levels of intracellular
oxidized glutathione, redox-sensitive
dye oxidation, and decreased
glucose utilization via multiple metabolic pathways including the tricarboxylic acid cycle. 2-DG/BSO/AUR
treatment delayed the growth of
tumors composed of intermediate radioresistant cells and effectively radiosensitized these
tumors at clinically relevant radiation doses both in vitro and in vivo Overall, our results support inhibition of glycolysis and intracellular redox metabolism as an effective alternative
drug strategy for the treatment of highly glycolytic and radioresistant
cervical cancers.Significance: This study suggests a simple metabolic approach to strike at an apparent Achilles' heel in highly glycolytic, radioresistant forms of
cervical cancers, possibly with broader applications in
cancer therapy.
Cancer Res; 78(6); 1392-403. ©2018 AACR.