Figure 4.

Effects of DNA-damaging topoisomerase inhibitors (A-C) and non-DNA damaging compounds (D, E) on expression of enzymes involved in glucose metabolism and apoptosis. OPM-2 cells were left untreated (0) or treated for 24 h with increasing concentrations of doxorubicin (A), etoposide (B) topotecan (C), bortezomib (D) and vincristine (E). Cell lysates were subjected to SDS-PAGE and immunoblotting using antibodies against GLUT-1, HKII, cleaved PARP and cleaved caspase-3. An anti-tubulin antibody was used as loading control. The effects of bortezomib (D) and vincristine (E) on down-regulation of GLUT-1 and HKII as well as on up-regulation of cleaved PARP and cleaved caspase-3 were more prominent than of doxorubicin (A), etoposide (B) and topotecan (C). Data were confirmed at least three times in independent experiments.