Childhood T-cell acute lymphoblastic leukemia (T-ALL) still remains a therapeutic challenge due to relapses which are resistant to further treatment. L-asparaginase (ASNase) is a key therapy component in pediatric T-ALL and lower sensitivity of leukemia cells to this drug negatively influences overall treatment efficacy and outcome. PTEN protein deletion and/or activation of the PI3K/Akt signaling pathway leading to altered cell growth and metabolism are emerging as a common feature in T-ALL. We herein investigated the relationship amongst PTEN deletion, ASNase sensitivity and glucose metabolism in T-ALL cells. First, we found significant differences in the sensitivity to ASNase amongst T-ALL cell lines. While cell lines more sensitive to ASNase were PTEN wild type (WT) and had no detectable level of phosphorylated Akt (P-Akt), cell lines less sensitive to ASNase were PTEN-null with high P-Akt levels. Pharmacological inhibition of Akt in the PTEN-null cells rendered them more sensitive to ASNase and lowered their glycolytic function which then resembled PTEN WT cells. In primary T-ALL cells, although P-Akt level was not dependent exclusively on PTEN expression, their sensitivity to ASNase could also be increased by pharmacological inhibition of Akt. In summary, we highlight a promising therapeutic option for T-ALL patients with aberrant PTEN/PI3K/Akt signaling.

• MeSH
• asparaginasa * farmakologie   terapeutické užití   MeSH
• dítě MeSH
• fosfatidylinositol-3-kinasy * genetika   metabolismus   MeSH
• fosfohydroláza PTEN * genetika   metabolismus   MeSH
• lidé MeSH
• lymfoblastická leukemie-lymfom z prekurzorových T-buněk * farmakoterapie   genetika   metabolismus   MeSH
• protoonkogenní proteiny c-akt metabolismus   MeSH
• signální transdukce MeSH
• T-lymfocyty metabolismus   MeSH
• Check Tag
• dítě MeSH
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• asparaginasa * MeSH
• fosfohydroláza PTEN * MeSH
• protoonkogenní proteiny c-akt MeSH
• PTEN protein, human MeSH Prohlížeč

BACKGROUND: Effectiveness of L-asparaginase administration in acute lymphoblastic leukemia treatment is mirrored in the overall outcome of patients. Generally, leukemia patients differ in their sensitivity to L-asparaginase; however, the mechanism underlying their inter-individual differences is still not fully understood. We have previously shown that L-asparaginase rewires the biosynthetic and bioenergetic pathways of leukemia cells to activate both anti-leukemic and pro-survival processes. Herein, we investigated the relationship between the metabolic profile of leukemia cells and their sensitivity to currently used cytostatic drugs. METHODS: Altogether, 19 leukemia cell lines, primary leukemia cells from 26 patients and 2 healthy controls were used. Glycolytic function and mitochondrial respiration were measured using Seahorse Bioanalyzer. Sensitivity to cytostatics was measured using MTS assay and/or absolute count and flow cytometry. Mitochondrial membrane potential was determined as TMRE fluorescence. RESULTS: Using cell lines and primary patient samples we characterized the basal metabolic state of cells derived from different leukemia subtypes and assessed their sensitivity to cytostatic drugs. We found that leukemia cells cluster into distinct groups according to their metabolic profile. Lymphoid leukemia cell lines and patients sensitive to L-asparaginase clustered into the low glycolytic cluster. While lymphoid leukemia cells with lower sensitivity to L-asparaginase together with resistant normal mononuclear blood cells gathered into the high glycolytic cluster. Furthermore, we observed a correlation of specific metabolic parameters with the sensitivity to L-asparaginase. Greater ATP-linked respiration and lower basal mitochondrial membrane potential in cells significantly correlated with higher sensitivity to L-asparaginase. No such correlation was found in the other cytostatic drugs tested by us. CONCLUSIONS: These data support that cell metabolism plays a prominent role in the treatment effect of L-asparaginase. Based on these findings, leukemia patients with lower sensitivity to L-asparaginase with no specific genetic characterization could be identified by their metabolic profile.

• Klíčová slova
• L-asparaginase, cancer metabolism, fatty acid oxidation, glycolysis, leukemia, mitochondrial membrane potential, mitochondrial respiration, resistance,
• MeSH
• akutní lymfatická leukemie krev   farmakoterapie   patologie   MeSH
• asparaginasa farmakologie   terapeutické užití   MeSH
• biosyntetické dráhy účinky léků   MeSH
• chemorezistence MeSH
• dítě MeSH
• glykolýza účinky léků   MeSH
• kojenec MeSH
• kostní dřeň patologie   MeSH
• lidé MeSH
• membránový potenciál mitochondrií účinky léků   MeSH
• metabolom účinky léků   MeSH
• mitochondrie účinky léků   metabolismus   MeSH
• mladiství MeSH
• mladý dospělý MeSH
• nádorové buněčné linie MeSH
• oxidativní fosforylace účinky léků   MeSH
• předškolní dítě MeSH
• protinádorové látky farmakologie   terapeutické užití   MeSH
• výsledek terapie MeSH
• Check Tag
• dítě MeSH
• kojenec MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• předškolní dítě MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• asparaginasa MeSH
• protinádorové látky MeSH

l-asparaginase (ASNase), a key component in the treatment of childhood acute lymphoblastic leukemia (ALL), hydrolyzes plasma asparagine and glutamine and thereby disturbs metabolic homeostasis of leukemic cells. The efficacy of such therapeutic strategy will depend on the capacity of cancer cells to adapt to the metabolic challenge, which could relate to the activation of compensatory metabolic routes. Therefore, we studied the impact of ASNase on the main metabolic pathways in leukemic cells. Treating leukemic cells with ASNase increased fatty-acid oxidation (FAO) and cell respiration and inhibited glycolysis. FAO, together with the decrease in protein translation and pyrimidine synthesis, was positively regulated through inhibition of the RagB-mTORC1 pathway, whereas the effect on glycolysis was RagB-mTORC1 independent. As FAO has been suggested to have a pro-survival function in leukemic cells, we tested its contribution to cell survival following ASNase treatment. Pharmacological inhibition of FAO significantly increased the sensitivity of ALL cells to ASNase. Moreover, constitutive activation of the mammalian target of rapamycin pathway increased apoptosis in leukemic cells treated with ASNase, but did not increase FAO. Our study uncovers a novel therapeutic option based on the combination of ASNase and FAO inhibitors.

• MeSH
• akutní lymfatická leukemie farmakoterapie   metabolismus   patologie   MeSH
• asparaginasa terapeutické užití   MeSH
• autofagie účinky léků   MeSH
• lidé MeSH
• mastné kyseliny metabolismus   MeSH
• monomerní proteiny vázající GTP fyziologie   MeSH
• mTORC1 MeSH
• multiproteinové komplexy fyziologie   MeSH
• nádorové buněčné linie MeSH
• oxidace-redukce MeSH
• pyrimidiny biosyntéza   MeSH
• TOR serin-threoninkinasy fyziologie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• asparaginasa MeSH
• mastné kyseliny MeSH
• monomerní proteiny vázající GTP MeSH
• mTORC1 MeSH
• multiproteinové komplexy MeSH
• pyrimidiny MeSH
• TOR serin-threoninkinasy MeSH