Non-Canonical Role of PDK1 as a Negative Regulator of Apoptosis through Macromolecular Complexes Assembly at the ER–Mitochondria Interface in Oncogene-Driven NSCLC

Here, we tested whether co-targeting of glucose metabolism and oncogene drivers may enhance tumor response to tyrosine kinase inhibitors (TKIs) in NSCLC. To this end, pyruvate dehydrogenase kinase 1 (PDK1) was stably downregulated in oncogene-driven NSCLC cell lines exposed or not to TKIs. H1993 and H1975 cells were stably transfected with scrambled (shCTRL) or PDK1-targeted (shPDK1) shRNA and then treated with MET inhibitor crizotinib (1 µM), double mutant EGFRL858R/T790M inhibitor WZ4002 (1 µM) or vehicle for 48 h. The effects of PDK1 knockdown on glucose metabolism and apoptosis were evaluated in untreated and TKI-treated cells. PDK1 knockdown alone did not cause significant changes in glycolytic cascade, ATP production and glucose consumption, but it enhanced maximal respiration in shPDK1 cells when compared to controls. When combined with TKI treatment, PDK1 downregulation caused a strong enhancement of OXPHOS and a marked reduction in key glycolytic enzymes. Furthermore, increased levels of apoptotic markers were found in shPDK1 cells as compared to shCTRL cells after treatment with TKIs. Co-immunoprecipitation studies showed that PDK1 interacts with PKM2, Bcl-2 and Bcl-xL, forming macromolecular complexes at the ER–mitochondria interface. Our findings showed that downregulation of PDK1 is able to potentiate the effects of TKIs through the disruption of macromolecular complexes involving PKM2, Bcl-2 and Bcl-xL.

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Blocking circ-CNST suppresses malignant behaviors of osteosarcoma cells and inhibits glycolysis through circ-CNST-miR-578-LDHA/PDK1 ceRNA networks

Journal of Orthopaedic Surgery and Research ◽

10.1186/s13018-021-02427-0 ◽

2021 ◽

Vol 16 (1) ◽

Author(s):

Rui Hu ◽

Shan Chen ◽

Jianxin Yan

Keyword(s):

Colony Formation ◽

Lactate Production ◽

Glucose Consumption ◽

Pyruvate Dehydrogenase Kinase ◽

Luciferase Reporter ◽

Migration And Invasion ◽

Physical Interaction ◽

U2os Cells

Abstract Background CircRNA CNST (circ-CNST) is a newly identified biomarker for prognosis of osteosarcoma (OS). However, its role in OS progression remains to be well documented. Methods Expression of circ-CNST, microRNA (miR)-578, lactate dehydrogenase A (LDHA), and pyruvate dehydrogenase kinase 1 (PDK1) was detected by quantitative real-time polymerase chain reaction and Western blotting. The physical interaction was confirmed by dual-luciferase reporter assay. Cell behaviors and glycolysis were measured by 3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide assay, colony formation assay, flow cytometry, transwell assays, xenograft experiment, and commercial kits. Results Circ-CNST was upregulated in human OS tissues and cells, accompanied with downregulation of miR-578 and upregulation of LDHA and PDK1. There were negative correlations between miR-578 expression and circ-CNST or LDHA/PDK1 in OS tissues. Moreover, high circ-CNST/LDHA/PDK1 or low miR-578 might predict shorter overall survival, advanced TNM stages, and lymph node metastasis. Physically, miR-578 was targeted by circ-CNST, and miR-578 could target LDHA/PDK1. Functionally, blocking circ-CNST and restoring miR-578 enhanced apoptosis rate and suppressed cell proliferation, colony formation, migration, and invasion in 143B and U2OS cells, accompanied with decreased glucose consumption, lactate production, and adenosine triphosphate (ATP)/adenosine diphosphate (ADP) ratio. Furthermore, in vivo growth of U2OS cells was retarded by silencing circ-CNST. Depletion of miR-578 could counteract the suppressive role of circ-CNST deficiency in 143B and U2OS cells, and restoring LDHA or PDK1 partially reversed the role of miR-578 inhibition as well. Conclusion Circ-CNST knockdown could antagonize malignant behaviors and glycolysis of OS cells by regulating miR-578-LDHA/PDK1 axes.

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Abstract 1209: Interleukin-6 Reduces Myocardial Glucose Metabolism by Altering AMPK, Insulin Signaling, and PKC-𝛉 in Mice

Circulation ◽

10.1161/circ.116.suppl_16.ii_245-b ◽

2007 ◽

Vol 116 (suppl_16) ◽

Author(s):

Zhiyou Zhang ◽

Hwi Jin Ko ◽

Dae Young Jung ◽

Zhexi Ma ◽

Jason K Kim

Keyword(s):

Glucose Metabolism ◽

Insulin Signaling ◽

Insulin Action ◽

Cardiac Metabolism ◽

Negative Regulator ◽

Saline Control ◽

Myocardial Glucose Metabolism ◽

Peripheral Organs

Increasing evidence implicates the role of inflammation in the pathogenesis of diabetes and complications. Inflammatory cytokines (IL-6, TNF-α) are elevated in obese diabetic subjects, and are shown to modulate glucose metabolism in peripheral organs. In this report, we examined the effects of IL-6 on cardiac metabolism and insulin action in vivo. Male C57BL/6 mice were intravenously treated with IL-6 (16 ng/hr) or saline (control) for 2 hrs, and [ 14 C]2-deoxyglucose was intravenously injected in awake mice to measure myocardial glucose metabolism (n=9~10). Hyperinsulinemic-euglycemic clamps (2.5 mU/kg/min insulin infusion) were also performed in IL-6 or saline-treated mice (n=4~5) to measure cardiac insulin action. Acute treatment with IL-6 caused a 25% increase in myocardial STAT3 activity and significantly reduced basal myocardial glucose metabolism (Fig. 1 ; * P< 0.05). IL-6 treatment also reduced insulin-stimulated glucose uptake in heart, and these effects were associated with marked decreases in AMPK activity (Thr-phosphorylation of AMPK; Fig. 2 ) and IRS-1 tyrosine phosphorylation (Fig. 3 ). Acute IL-6 treatment increased myocardial expression of PKC-𝛉, which has been shown to mediate insulin resistance in peripheral organs (Fig. 4 ). These results indicate that IL-6 is a potent negative regulator of myocardial glucose metabolism and insulin action, and the underlying mechanism may involve IL-6 mediated activation of PKC-𝛉 and defects in AMPK and insulin signaling activity. Thus, our findings suggest a potential role of IL-6 in the pathogenesis of diabetic heart failure.

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Tyrosine Kinase Inhibitor-Induced Hypertension: Role of Hypertension as a Biomarker in Cancer Treatment

Current Vascular Pharmacology ◽

10.2174/1570161117666190130165810 ◽

2019 ◽

Vol 17 (6) ◽

pp. 618-634 ◽

Cited By ~ 4

Author(s):

Cecilie Budolfsen ◽

Julie Faber ◽

Daniela Grimm ◽

Marcus Krüger ◽

Johann Bauer ◽

...

Keyword(s):

Adverse Effects ◽

Tyrosine Kinase ◽

Cancer Treatment ◽

Kinase Inhibitors ◽

Kinase Inhibitor ◽

Prognostic Models ◽

Capillary Rarefaction ◽

Potential Biomarker ◽

Tki Treatment

:Cancer treatment is an area of continuous improvement. Therapy is becoming more targeted and the use of anti-angiogenic agents in multiple cancers, specifically tyrosine kinase inhibitors (TKIs), has demonstrated prolonged survival outcomes compared with previous drugs. Therefore, they have become a well-established part of the treatment.:Despite good results, there is a broad range of moderate to severe adverse effects associated with treatment. Hypertension (HTN) is one of the most frequent adverse effects and has been associated with favourable outcomes (in terms of cancer treatment) of TKI treatment.:High blood pressure is considered a class effect of TKI treatment, although the mechanisms have not been fully described. Three current hypotheses of TKI-associated HTN are highlighted in this narrative review. These include nitric oxide decrease, a change in endothelin-1 levels and capillary rarefaction.:Several studies have investigated HTN as a potential biomarker of TKI efficacy. HTN is easy to measure and adding this factor to prognostic models has been shown to improve specificity. HTN may become a potential biomarker in clinical practice involving treating advanced cancers. However, data are currently limited by the number of studies and knowledge of the mechanism of action.

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Role of pyruvate dehydrogenase kinase 1 (PDHK1) in tumorigenesis and metastasis of ovarian cancer

10.5353/th_b5719443 ◽

2015 ◽

Author(s):

Yuxin Jiang

Keyword(s):

Ovarian Cancer ◽

Pyruvate Dehydrogenase ◽

Pyruvate Dehydrogenase Kinase ◽

Pyruvate Dehydrogenase Kinase 1

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PHD2 Is a Regulator for Glycolytic Reprogramming in Macrophages

Molecular and Cellular Biology ◽

10.1128/mcb.00236-16 ◽

2016 ◽

Vol 37 (1) ◽

Cited By ~ 12

Author(s):

Annemarie Guentsch ◽

Angelika Beneke ◽

Lija Swain ◽

Katja Farhat ◽

Shunmugam Nagarajan ◽

...

Keyword(s):

Pyruvate Dehydrogenase ◽

Critical Role ◽

Hypoxia Inducible Factor ◽

Pyruvate Dehydrogenase Kinase ◽

Metabolic Phenotype ◽

Protein Levels ◽

Dehydrogenase Enzyme ◽

Pyruvate Dehydrogenase Kinase 1 ◽

And Function

ABSTRACT The prolyl-4-hydroxylase domain (PHD) enzymes are regarded as the molecular oxygen sensors. There is an interplay between oxygen availability and cellular metabolism, which in turn has significant effects on the functionality of innate immune cells, such as macrophages. However, if and how PHD enzymes affect macrophage metabolism are enigmatic. We hypothesized that macrophage metabolism and function can be controlled via manipulation of PHD2. We characterized the metabolic phenotypes of PHD2-deficient RAW cells and primary PHD2 knockout bone marrow-derived macrophages (BMDM). Both showed typical features of anaerobic glycolysis, which were paralleled by increased pyruvate dehydrogenase kinase 1 (PDK1) protein levels and a decreased pyruvate dehydrogenase enzyme activity. Metabolic alterations were associated with an impaired cellular functionality. Inhibition of PDK1 or knockout of hypoxia-inducible factor 1α (HIF-1α) reversed the metabolic phenotype and impaired the functionality of the PHD2-deficient RAW cells and BMDM. Taking these results together, we identified a critical role of PHD2 for a reversible glycolytic reprogramming in macrophages with a direct impact on their function. We suggest that PHD2 serves as an adjustable switch to control macrophage behavior.

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Inhibition of pyruvate dehydrogenase kinase 1 enhances the anti-cancer effect of EGFR tyrosine kinase inhibitors in non-small cell lung cancer

European Journal of Pharmacology ◽

10.1016/j.ejphar.2018.09.016 ◽

2018 ◽

Vol 838 ◽

pp. 41-52 ◽

Cited By ~ 6

Author(s):

Zheng Yang ◽

Shao-Lin Zhang ◽

Xiaohui Hu ◽

Kin Yip Tam

Keyword(s):

Lung Cancer ◽

Small Cell Lung Cancer ◽

Pyruvate Dehydrogenase ◽

Kinase Inhibitors ◽

Small Cell ◽

Pyruvate Dehydrogenase Kinase ◽

Small Cell Lung ◽

Anti Cancer ◽

Egfr Tyrosine Kinase Inhibitors ◽

Pyruvate Dehydrogenase Kinase 1

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Inhibition of Pyruvate Dehydrogenase Kinase as a Therapeutic Strategy against Cancer

Current Topics in Medicinal Chemistry ◽

10.2174/1568026618666180523105756 ◽

2018 ◽

Vol 18 (6) ◽

pp. 444-453 ◽

Cited By ~ 11

Author(s):

Swatishree Sradhanjali ◽

Mamatha M. Reddy

Keyword(s):

Glucose Metabolism ◽

Pyruvate Dehydrogenase ◽

Pyruvate Dehydrogenase Complex ◽

Metabolic Reprogramming ◽

Pyruvate Dehydrogenase Kinase ◽

Glutamine Metabolism ◽

Altered Glucose ◽

Elevated Expression ◽

Related Drug

Cancer cells alter their metabolism to support the uninterrupted supply of biosynthetic molecules required for continuous proliferation. Glucose metabolism is frequently reprogrammed in several tumors in addition to fatty acid, amino acid and glutamine metabolism. Pyruvate Dehydrogenase Kinase (PDK) is a gatekeeper enzyme involved in altered glucose metabolism in tumors. There are four isoforms of PDK (1 to 4) in humans. PDK phosphorylates E1α subunit of pyruvate dehydrogenase complex (PDC) and inactivates it. PDC decarboxylates pyruvate to acetyl CoA, which is further metabolized in mitochondria. Overexpression of PDK was observed in several tumors and is frequently associated with chemotherapy related drug resistance, invasion and metastasis. Elevated expression of PDK leads to a shift in glucose metabolism towards glycolysis instead of oxidative phosphorylation. This review summarizes recent literature related to the role of PDKs in cancer and their inhibition as a strategy. In particular, we discuss the role of PDK in tumor progression, metabolic reprogramming in stem cells, and their regulation by miRNAs and lncRNAs, oncogenes and tumor suppressors. Further, we review strategies aimed at targeting PDK to halt tumor growth and progression.

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ABT-737 Cooperates in a Strong Synergism with Tyrosine Kinase Inhibitors to Induce Apoptosis of Chronic Myeloid Leukemia Cells.

Blood ◽

10.1182/blood.v114.22.3246.3246 ◽

2009 ◽

Vol 114 (22) ◽

pp. 3246-3246

Author(s):

Francis Belloc ◽

Kelly Airiau ◽

Marie Jeanneteau ◽

Francois-Xavier Mahon

Keyword(s):

Tyrosine Kinase ◽

Tyrosine Kinase Inhibitors ◽

Caspase 3 ◽

Kinase Inhibitors ◽

K562 Cells ◽

Caspase Inhibitor ◽

Tyrosine Kinase Inhibition ◽

Apoptotic Proteins ◽

Tki Treatment

Abstract Abstract 3246 Poster Board III-183 Introduction BCR-ABL confers to several cell lines an apoptosis-resistant phenotype that is critically dependent on its kinase activity. It has been shown that BCR-ABL can block the mitochondrial step of apoptosis and that tyrosine kinase inhibition induces apoptosis in BCR-ABL expressing cells. Several pro- and anti-apoptotic proteins of the Bcl-2 family modulate the mitochondrial apoptotic signal. Amongst them, anti-apoptotic Bcl-xL and Mcl-1 are induced by BCR-ABL. Several studies underlined the probable role of Bim expression during tyrosine kinase inhibition-induced apoptosis and we previously confirmed that cells which were depleted in Bim were unable to undergo apoptosis when treated by two tyrosine kinase inhibitors (TKI) : imatinib (IMA) and nilotinib (NIL). Altogether, these results strongly support the prominent role of the balance between pro- and anti-apoptotic proteins of the Bcl-2 family in the apoptotic response of CML cells after TKI treatment. It has been shown that Bim actually is an indirect activator of apoptosis through its anti-Bcl-xL, -Mcl-1 and -Bcl-2 effects. Recently, ABT-737, a small molecule which binds Bcl-2 and Bcl-xL but not Mcl-1, was shown to induce apoptosis in several tumour cell types. In this study, we verify if ABT-737 could cooperate efficiently with the Bim stabilizing TKI. Methods and Results K562 cells were incubated with increasing concentrations of either imatinib or nilotinib, alone or in combination with ABT-737, in a constant ratio. Both TKI and ABT-737 induced a dose dependant apoptosis and the combination of IMA or NIL with ABT-737 resulted in a synergistic cooperation to induce apoptosis. The combination index (CI) calculated using the Calcusyn software was 0.05 for ABT-737 and either IMA or NIL at ED90. Similar experiments were performed on CD34 expressing cells from 12 CML patients, and the strong synergism of ABT-737 with both IMA and NIL was confirmed with a mean CI of 0.25. To elucidate the mechanisms underlying this cooperation, we analyzed the Bcl-2 family proteins expression and confirmed the increase of Bim and the decrease of Bcl-xL due to TKI treatment while ABT-737 was without effect on the expression of these proteins. Pull-down experiments on K562 cells using anti-Bcl-2 and anti-Bcl-xL antibodies followed by analysis of Bim showed that ABT-737 decreases the interaction between BIM and Bcl-2 or Bcl-xL in cell free system as in intact cells. Moreover, Bim was co-immunoprecipitated more efficiently by anti-MCL-1 antibodies when it was displaced from Bcl-2 and Bcl-xL by ABT-737. This brings some mechanistic support to the complementary effects of TKI (stabilizing Bim) and ABT-737. The expression of several anti-apoptotic proteins was also analyzed. Surprisingly, the combination of TKI with ABT-737 induced a dramatic decrease in XIAP content while each inhibitor alone was without effect on this protein. The decrease in XIAP was accompanied by an increase in caspase 3 cleavage. Cell sorting experiments showed that the decrease in XIAP preceded the drop in mitochondrial membrane potential and the activation of caspase 3 and it was only partly inhibited by a pan-caspase inhibitor and not at all by proteasome or cathepsin B inhibitors. Conclusion ABT-737 cooperates with TKI to induce apoptosis of CML cells. This cooperation can be explained in part by the increase in Bim activity induced by TKI associated to the inactivation of Bcl-2, -xL by ABT-737. However, a side effect at the level of the caspase inhibitor XIAP also seems to participate, resulting in a strong synergism. Thus, the association between TKI and Bcl-2 inhibitors could be a facilitating strategy to induce apoptosis in some BCR-ABL expressing cells resistant to TKI alone. Disclosures Mahon: Amgen: Honoraria; Novartis Pharma: Consultancy, Honoraria, Research Funding; Alexion: Consultancy, Honoraria.

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