The accumulation of 2-deoxyglucose (2-DG), a glycolytic inhibitor, was investigated in a human nasal carcinoma cell line, RPMI-2650 and two of its drug-resistant variants (selected with taxol and melphalan) to assess manipulation of glycolytic potential as a selective means of reducing resistance. 2-DG uptake was increased 3-fold and 9.9-fold in taxol- and melphalan-resistant variants of RPMI-2650, respectively. Two of the principal factors associated with increased 2-DG uptake, namely glucose transporters and hexokinase activity, were increased in the resistant variants. Other changes in glucose metabolism that may affect 2-DG as an antimetabolite were observed, including increases in glucose-6-phosphate dehydrogenase of 10-fold and 100-fold for taxol- and melphalan-resistant variants, respectively, suggesting higher pentose phosphate activity; increased glutamine utilisation and greater sensitivity to iodoacetic acid-induced depletion of ATP levels in the parent relative to the resistant variants.
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