Inhibition of glycolysis modulates prednisolone resistance in acute lymphoblastic leukemia cells

Abstract

Treatment failure in pediatric acute lymphoblastic leukemia (ALL) is related to cellular resistance to glucocorticoids (eg, prednisolone). Recently, we demonstrated that genes associated with glucose metabolism are differentially expressed between prednisolone-sensitive and prednisolone-resistant precursor Blineage leukemic patients. Here, we show that prednisolone resistance is associated with increased glucose consumption and that inhibition of glycolysis sensitizes prednisolone-resistant ALL cell lines to glucocorticoids. Treatment of prednisolone-resistant Jurkat and Molt4 cells with 2-deoxy-D-glucose (2-DG), lonidamine (LND), or 3-bromopyruvate (3-BrPA) increased the in vitro sensitivity to glucocorticoids, while treatment of the prednisolone-sensitive cell lines Tom-1 and RS4; 11 did not influence drug cytotoxicity. This sensitizing effect of the glycolysis inhibitors in glucocorticoid-resistant ALL cells was not found for other classes of antileukemic drugs (ie, vincristine and daunorubicin). Moreover, downregulation of the expression of GAPDH by RNA interference also sensitized to prednisolone, comparable with treatment with glycolytic inhibitors. Importantly, the ability of 2-DG to reverse glucocorticoid resistance was not limited to cell lines, but was also observed in isolated primary ALL cells from patients. Together, these findings indicate the importance of the glycolytic pathway in glucocorticoid resistance in ALL and suggest that targeting glycolysis is a viable strategy for modulating prednisolone resistance in ALL. IntroductionTreatment of childhood acute lymphoblastic leukemia (ALL) includes the use of several classes of chemotherapeutic agents, including glucocorticoids (GCs), Vinca alkaloids, and anthracyclines. The glucocorticoids prednisolone and dexamethasone play an essential role in essentially all therapy protocols, due to their ability to block cell-cycle progression and induce apoptosis in ALL cells. [1][2][3] Although treatment of childhood ALL has greatly improved over the past decades, conventional combination chemotherapy still fails in approximately 20% of the patients. 4 Most therapeutic failures can be explained by cellular resistance to antileukemic drugs. 5 Resistance to prednisolone at initial diagnosis in particular is related to an unfavorable event-free survival. In addition, in vitro prednisolone resistance is recognized as an important negative parameter for long-term clinical outcome, even in patients who initially have a good in vivo response to glucocorticoids. [6][7][8] Therefore, it is important to find alternative therapies that can reverse resistance toward prednisolone and dexamethasone.Previous experiments performed in our laboratories showed that prednisolone resistance in precursor B-ALL patients is associated with an increased expression of genes involved in glucose metabolism, suggesting that glucocorticoid resistance may be linked with an increased rate of glycolysis. 9 Glycolysis is a series of metabolic reactions by which 1 molecule of glucose is conve...

Inhibition of Akt Potentiates 2-DG–Induced Apoptosis via Downregulation of UPR in Acute Lymphoblastic Leukemia

“…Moreover, we show that the addition of D-mannose not only rescues 2-DG-treated cells but also correlates with the downregulation of UPR markers. Therefore, our data are consistent with published reports indicating that inhibition of glycolysis modulates prednisolone resistance in ALL and that very high doses of 2-DG (40 mmol/L) induce cytotoxicity in lymphoma cell lines (39,40).…”

Dichloroacetate metabolically targeted therapy defeats cytotoxicity of standard anticancer drugs

“…from fluorine-18-fluorodeoxyglucose (FDG) positron emission tomography (PET), gene and protein expression profiling) that paediatric like adult tumours have a high glucose turnover and that anaerobic glycolysis might also be relevant for paediatric malignancies [18][19][20][21][22]. Furthermore, the expression of the four PDK isoforms and/or of antiapoptotic proteins, like Bcl-2, PUMA or survivin might have influenced the sensitivity to DCA [5,7].…”

The synergism of MCL1 and glycolysis on pediatric acute lymphoblastic leukemia cell survival and prednisolone resistance

“…6,7 In addition, we and others discovered that glycolysis is increased in prednisolone-resistant leukemic cells. 8,9 Microarray analysis on primary precursor B-acute lymphoblastic leukemia (BCP-ALL) cells of pediatric patients indicated an increased expression of several glycolytic enzymes and glucose transporters in prednisolone resistant patients. 3 Furthermore, 2-deoxyglucose (2-DG), an inhibitor of glycolysis, sensitized both leukemic cell lines and patients' ALL cells to prednisolone.…”

“…3 Furthermore, 2-deoxyglucose (2-DG), an inhibitor of glycolysis, sensitized both leukemic cell lines and patients' ALL cells to prednisolone. 8,9 For three reasons, we now hypothesize that anti-apoptosis sustained by MCL1, and glycolysis are linked and concomitantly induce drug resistance in leukemia. 1) Cellular respiration and apoptosis are closely related survival pathways both associated with prednisolone resistance, [6][7][8][9] and other targeted molecular leukemia therapies, such as imatinib.…”

“…18 To date, various mechanisms that sensitize leukemic cells in vitro to prednisolone have been described, including inhibition of the prednisolone interconverter 11β-HSD, knockdown of the glucocorticoid-dependent transcription regulator SMARCA4, inhibition of the voltage-dependent channel hERG1, which signals to ERK/PI3K/Akt survival pathways, knockdown of the calcium scavengers S100A8/S100A9, downregulation of anti-apoptotic MCL1, upregulation of pro-apoptotic BIM, and inhibition of glycolysis. 6,8,9,[19][20][21][22] Sensitizing cells to prednisolone may, therefore, require a multifactorial approach. In this study, we provide evidence that reduction of MCL1 levels and inhibition of glycolysis synergistically inhibits leukemic survival and concomitantly sensitizes to prednisolone in ALL cells.…”