Dataset Information

Phenothiazines induce PP2A-mediated apoptosis in T cell acute lymphoblastic leukemia.

ABSTRACT: T cell acute lymphoblastic leukemia (T-ALL) is an aggressive cancer that is frequently associated with activating mutations in NOTCH1 and dysregulation of MYC. Here, we performed 2 complementary screens to identify FDA-approved drugs and drug-like small molecules with activity against T-ALL. We developed a zebrafish system to screen small molecules for toxic activity toward MYC-overexpressing thymocytes and used a human T-ALL cell line to screen for small molecules that synergize with Notch inhibitors. We identified the antipsychotic drug perphenazine in both screens due to its ability to induce apoptosis in fish, mouse, and human T-ALL cells. Using ligand-affinity chromatography coupled with mass spectrometry, we identified protein phosphatase 2A (PP2A) as a perphenazine target. T-ALL cell lines treated with perphenazine exhibited rapid dephosphorylation of multiple PP2A substrates and subsequent apoptosis. Moreover, shRNA knockdown of specific PP2A subunits attenuated perphenazine activity, indicating that PP2A mediates the drug's antileukemic activity. Finally, human T-ALLs treated with perphenazine exhibited suppressed cell growth and dephosphorylation of PP2A targets in vitro and in vivo. Our findings provide a mechanistic explanation for the recurring identification of phenothiazines as a class of drugs with anticancer effects. Furthermore, these data suggest that pharmacologic PP2A activation in T-ALL and other cancers driven by hyperphosphorylated PP2A substrates has therapeutic potential.

SUBMITTER: Gutierrez A

PROVIDER: S-EPMC3904599 | biostudies-literature | 2014 Feb

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Phenothiazines induce PP2A-mediated apoptosis in T cell acute lymphoblastic leukemia.

Gutierrez Alejandro A Pan Li L Groen Richard W J RW Baleydier Frederic F Kentsis Alex A Marineau Jason J Grebliunaite Ruta R Kozakewich Elena E Reed Casie C Pflumio Francoise F Poglio Sandrine S Uzan Benjamin B Clemons Paul P VerPlank Lynn L An Frank F Burbank Jason J Norton Stephanie S Tolliday Nicola N Steen Hanno H Weng Andrew P AP Yuan Huipin H Bradner James E JE Mitsiades Constantine C Look A Thomas AT Aster Jon C JC

The Journal of clinical investigation 20140109 2

T cell acute lymphoblastic leukemia (T-ALL) is an aggressive cancer that is frequently associated with activating mutations in NOTCH1 and dysregulation of MYC. Here, we performed 2 complementary screens to identify FDA-approved drugs and drug-like small molecules with activity against T-ALL. We developed a zebrafish system to screen small molecules for toxic activity toward MYC-overexpressing thymocytes and used a human T-ALL cell line to screen for small molecules that synergize with Notch inhi ...[more]

PMID: 24401270

Similar Datasets

Project description:The metabolic profiles of cancer cells have long been acknowledged to be altered and to provide new therapeutic opportunities. In particular, a wide range of both solid and liquid tumors use aerobic glycolysis to supply energy and support cell growth. This metabolic program leads to high rates of glucose consumption through glycolysis with secretion of lactate even in the presence of oxygen. Identifying the limiting events in aerobic glycolysis and the response of cancer cells to metabolic inhibition is now essential to exploit this potential metabolic dependency. Here, we examine the role of glucose uptake and the glucose transporter Glut1 in the metabolism and metabolic stress response of BCR-Abl+ B-cell acute lymphoblastic leukemia cells (B-ALL). B-ALL cells were highly glycolytic and primary human B-ALL samples were dependent on glycolysis. We show B-ALL cells express multiple glucose transporters and conditional genetic deletion of Glut1 led to a partial loss of glucose uptake. This reduced glucose transport capacity, however, was sufficient to metabolically reprogram B-ALL cells to decrease anabolic and increase catabolic flux. Cell proliferation decreased and a limited degree of apoptosis was also observed. Importantly, Glut1-deficient B-ALL cells failed to accumulate in vivo and leukemic progression was suppressed by Glut1 deletion. Similarly, pharmacologic inhibition of aerobic glycolysis with moderate doses of 2-deoxyglucose (2-DG) slowed B-ALL cell proliferation, but extensive apoptosis only occurred at high doses. Nevertheless, 2-DG induced the pro-apoptotic protein Bim and sensitized B-ALL cells to the tyrosine kinase inhibitor Dasatinib in vivo. Together, these data show that despite expression of multiple glucose transporters, B-ALL cells are reliant on Glut1 to maintain aerobic glycolysis and anabolic metabolism. Further, partial inhibition of glucose metabolism is sufficient to sensitize cancer cells to specifically targeted therapies, suggesting inhibition of aerobic glycolysis as a plausible adjuvant approach for B-ALL therapies.

Project description:T‑cell acute lymphoblastic leukemia (T‑ALL) is a common pediatric malignancy, characterized by the abnormal presence of immature T‑cell progenitors. Conventional treatments for T‑ALL fail to prevent or cure the disease, with a high‑risk of recurrence after the first remission. Thus, medical options are in demand to develop novel therapies for patients suffering with T‑ALL. Niclosamide, a traditional oral anti‑helminthic drug, has been reported to be a potential anticancer agent that regulates intracellular signaling pathways. Few studies have yet investigated the effects of niclosamide on the development of T‑ALL. Here, the present study aimed to investigate the anti‑leukemia effects of niclosamide on T‑ALL. We first hypothesized that the suppressive effects of niclosamide on the tumor growth of T‑ALL are exerted by regulating autophagy and apoptosis. Following niclosamide treatment, T‑ALL cell viability was evaluated using MTT assay, and apoptosis with Annexin V/propidium iodide staining. In T‑ALL cells treated with niclosamide, changes in apoptosis‑ and autophagy‑related proteins were analyzed by western blotting. In addition, in an in vivo model, T‑ALL xenograft mice were used to study the anti‑leukemia effects of niclosamide. The results showed that niclosamide significantly reduced the viability of Jurkat and CCRF‑CEM T‑ALL cells in both a dose‑ and time‑dependent manner. Niclosamide significantly activated the early and late phases of apoptosis in Jurkat (at 2 µM) and CCRF‑CEM cells (at 1 µM). Furthermore, niclosamide upregulated protein expression of cleaved caspase‑3 and LC3B, while downregulated those of Bcl‑2 and p62, in a dose‑dependent manner in both Jurkat and CCRF‑CEM cells. The in vivo results showed that niclosamide treatment significantly suppressed tumor growth and the disease progression in T‑ALL xenograft mice by activating cleaved caspase‑3 and LC3B. We conclude that niclosamide plays an anti‑leukemia role, and that it represents a novel approach for the treatment of T‑ALL.

Dataset Information

Phenothiazines induce PP2A-mediated apoptosis in T cell acute lymphoblastic leukemia.

Publications

Phenothiazines induce PP2A-mediated apoptosis in T cell acute lymphoblastic leukemia.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets