Neuroblastoma is the most common extracranial solid tumour of infancy. Pathological activation of glucose consumption, glycolysis and glycolysis-activating Akt kinase occur frequently in neuroblastoma cells, and these changes correlate with poor prognosis of patients. Therefore, several inhibitors of glucose utilization and the Akt kinase activity are in preclinical trials as potential anti-cancer drugs. However, metabolic plasticity of cancer cells might undermine efficacy of this approach. In this work, we identified oxidative phosphorylation as compensatory mechanism preserving viability of neuroblastoma cells with inhibited glucose uptake/Akt kinase. It was oxidative phosphorylation that maintained intracellular level of ATP and proliferative capacity of these cells. The oxidative phosphorylation inhibitors (rotenone, tetrathiomolybdate) synergized with inhibitor of the Akt kinase/glucose uptake in down-regulation of both viability of neuroblastoma cells and clonogenic potential of cells forming neuroblastoma spheroids. Interestingly, tetrathiomolybdate acted as highly specific inhibitor of oxygen consumption and activator of lactate production in neuroblastoma cells, but not in normal fibroblasts and neuronal cells. Moreover, the reducing effect of tetrathiomolybdate on cell viability and the level of ATP in the cells with inhibited Akt kinase/glucose uptake was also selective for neuroblastoma cells. Therefore, efficient elimination of neuroblastoma cells requires inhibition of both glucose uptake/Akt kinase and oxidative phosphorylation activities. The use of tetrathiomolybdate as a mitochondrial inhibitor contributes to selectivity of this combined treatment, preferentially targeting neuroblastoma cells.
- MeSH
- adenosintrifosfát metabolismus MeSH
- buněčné dýchání účinky léků MeSH
- down regulace účinky léků MeSH
- fibroblasty účinky léků metabolismus MeSH
- fosforylace účinky léků MeSH
- glukosa metabolismus MeSH
- inhibitory proteinkinas farmakologie MeSH
- kyselina mléčná biosyntéza MeSH
- lidé MeSH
- mitochondrie účinky léků metabolismus MeSH
- molybden farmakologie MeSH
- myši inbrední C57BL MeSH
- nádorové buněčné linie MeSH
- neuroblastom enzymologie metabolismus patologie MeSH
- neurony účinky léků metabolismus MeSH
- oxidativní fosforylace účinky léků MeSH
- protoonkogenní proteiny c-akt antagonisté a inhibitory metabolismus MeSH
- spotřeba kyslíku účinky léků MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
BACKGROUND: Resistance of cancer cells to chemotherapeutic agents is a major cause of treatment failure in patients with cancer. The drug resistance of tumor cells can be significantly modified by specific features of tumor microenvironment, such as oxygen depletion (hypoxia), glucose/energy deprivation and acidosis. METHODS: The effects of acidic tumor-like microenvironment on cytotoxicity of antabuse (disulfiram, DSF)/Cu(2+) complexes to MCF-7 breast carcinoma and HT-29 colon carcinoma cells were studied. RESULTS: We show that acidic pH significantly potentiates toxicity of DSF/Cu(2+) complex to breast and colon cancer cells. This phenomenon is associated with changes in cell metabolism, altered Akt kinase and NFκB activity and increased reactive oxygen species production. CONCLUSION: Specific pH of tumor microenvironment enhances cytotoxicity of DSF/Cu(2+) to breast and colon cancer cells.
- MeSH
- buňky HT-29 MeSH
- disulfiram chemie MeSH
- fosforylace MeSH
- komplexní sloučeniny chemická syntéza chemie toxicita MeSH
- koncentrace vodíkových iontů MeSH
- lidé MeSH
- měď chemie MeSH
- MFC-7 buňky MeSH
- nádorové mikroprostředí účinky léků MeSH
- nádory prsu metabolismus patologie MeSH
- nádory tračníku metabolismus patologie MeSH
- NF-kappa B metabolismus MeSH
- proliferace buněk účinky léků MeSH
- protinádorové látky chemická syntéza chemie toxicita MeSH
- protoonkogenní proteiny c-akt metabolismus MeSH
- reaktivní formy kyslíku metabolismus MeSH
- viabilita buněk účinky léků MeSH
- Check Tag
- lidé MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Growth of tumor cells depends on sufficient supply of fermentable substrate, such as glucose. This provokes development of new anticancer therapies based on dietary restrictions. However, some tumor cells can lower their glucose dependency and activate processes of ATP formation/saving to retain viability even in limited glucose supply. In addition, tumor cells often lose sensitivity to many conventional anticancer drugs in the low-glucose conditions. Thus, development of the drugs effectively killing the tumor cells in nutrient-limited conditions is necessary. In this study, we show an enhanced cytotoxicity of tetrathiomolybdate, the drug exhibiting antiangiogenic and tumor-suppressing effects, to neuroblastoma SH-SY5Y and SK-N-BE(2) cells in the low-glucose conditions. This preference results from the tetrathiomolybdate-induced upregulation of cell dependency on glucose. The cells treated with tetrathiomolybdate increase the uptake of glucose, production of lactate, activate the Akt- and AMPK-signaling pathways and downregulate COX IV. In cells growing in the low-glucose conditions, these events result in significant decrease of the intracellular ATP supply and apoptosis. We propose tetrathiomolybdate as suitable agent to be used in combination with dietary restrictions in therapy of neuroblastoma.
- MeSH
- apoptóza účinky léků MeSH
- down regulace MeSH
- glukosa metabolismus MeSH
- hypoxie farmakoterapie MeSH
- inhibitory angiogeneze farmakologie MeSH
- lidé MeSH
- molybden farmakologie MeSH
- nádorové buněčné linie MeSH
- nádorové mikroprostředí účinky léků MeSH
- neuroblastom metabolismus patologie MeSH
- proliferace buněk účinky léků MeSH
- proteinkinasy aktivované AMP genetika metabolismus MeSH
- protoonkogenní proteiny c-akt genetika metabolismus MeSH
- signální transdukce MeSH
- viabilita buněk účinky léků MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
White blood cell (WBC) count is considered a prognostic risk factor in acute myeloid leukemia. As density of leukemic cells increases, the cytotoxic activity of certain anticancer drugs, such as vincristine and doxorubicin, progressively decreases. In this study, we investigated the cell density-dependent induction of apoptosis of human acute myeloid leukemia U937 and ML-1 cells by disulfiram (DSF), the dithiocarbamate drug recently proposed for treatment of human cancers. This effect is dependent on uptake of extracellular copper and its intracellular accumulation. High-density cells cannot uptake and accumulate this metal to a sufficient level that would allow induction of apoptosis due to progressive decrease of its extracellular concentration. Simple addition of copper can resume sensitivity of high-density leukemic cells to DSF and improve efficiency of anti-leukemic therapies using this drug, thus providing benefit to patients with high WBC count.
- MeSH
- acetylcystein farmakologie MeSH
- buněčná smrt účinky léků MeSH
- chemorezistence účinky léků MeSH
- disulfiram farmakologie MeSH
- inhibitory enzymů farmakologie MeSH
- intracelulární prostor metabolismus účinky léků MeSH
- ionty MeSH
- kultivační média speciální MeSH
- lidé MeSH
- měď farmakologie MeSH
- myeloidní leukemie patologie MeSH
- nádorové buněčné linie MeSH
- počet buněk MeSH
- proliferace buněk účinky léků MeSH
- viabilita buněk účinky léků MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- práce podpořená grantem MeSH
The p53 protein can control cell cycle progression, programmed cell death, and differentiation of many cell types. Ectopic expression of p53 can resume capability of cell cycle arrest, differentiation, and apoptosis in various leukemic cell lines. In this work, we expressed human p53 protein in v-Myb-transformed chicken monoblasts. We found that even this protein possessing only 53% amino acid homology to its avian counterpart can significantly alter morphology and physiology of these cells causing the G2-phase cell cycle arrest and early monocytic differentiation. Our results document that the species-specific differences of the p53 molecules, promoters/enhancers, and co-factors in avian and human cells do not interfere with differentiation- and cell cycle arrest promoting capabilites of the p53 tumor suppressor even in the presence of functional v-Myb oncoprotein. The p53-induced differentiation and cell cycle arrest of v-Myb-transformed monoblasts are not associated with apoptosis suggesting that the p53-driven pathways controlling apoptosis and differentiation/proliferation are independent.
- MeSH
- apoptóza genetika MeSH
- buněčná diferenciace fyziologie genetika MeSH
- buněčný cyklus genetika MeSH
- financování organizované MeSH
- G2 fáze genetika MeSH
- inhibitory růstu fyziologie genetika MeSH
- kur domácí MeSH
- lidé MeSH
- monocyty cytologie MeSH
- nádorový supresorový protein p53 fyziologie genetika MeSH
- onkogenní proteiny v-myb genetika MeSH
- proliferace buněk MeSH
- signální transdukce genetika MeSH
- transfekce MeSH
- transformované buněčné linie MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
