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Han L, Jiang Y, Shi M, Gan L, Wu Z, Xue M, Zhu Y, Xiong C, Wang T, Lin X, Shen B, Jiang L, Chen H. LIPH contributes to glycolytic phenotype in pancreatic ductal adenocarcinoma by activating LPA/LPAR axis and maintaining ALDOA stability. J Transl Med 2023; 21:838. [PMID: 37990271 PMCID: PMC10664664 DOI: 10.1186/s12967-023-04702-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Accepted: 11/03/2023] [Indexed: 11/23/2023] Open
Abstract
BACKGROUND LIPH, a membrane-associated phosphatidic acid-selective phospholipase A1a, can produce LPA (Lysophosphatidic acid) from PA (Phosphatidic acid) on the outer leaflet of the plasma membrane. It is well known that LIPH dysfunction contributes to lipid metabolism disorder. Previous study shows that LIPH was found to be a potential gene related to poor prognosis with pancreatic ductal adenocarcinoma (PDAC). However, the biological functions of LIPH in PDAC remain unclear. METHODS Cell viability assays were used to evaluate whether LIPH affected cell proliferation. RNA sequencing and immunoprecipitation showed that LIPH participates in tumor glycolysis by stimulating LPA/LPAR axis and maintaining aldolase A (ALDOA) stability in the cytosol. Subcutaneous, orthotopic xenograft models and patient-derived xenograft PDAC model were used to evaluate a newly developed Gemcitabine-based therapy. RESULTS LIPH was significantly upregulated in PDAC and was related to later pathological stage and poor prognosis. LIPH downregulation in PDAC cells inhibited colony formation and proliferation. Mechanistically, LIPH triggered PI3K/AKT/HIF1A signaling via LPA/LPAR axis. LIPH also promoted glycolysis and de novo synthesis of glycerolipids by maintaining ALDOA stability in the cytosol. Xenograft models show that PDAC with high LIPH expression levels was sensitive to gemcitabine/ki16425/aldometanib therapy without causing discernible side effects. CONCLUSION LIPH directly bridges PDAC cells and tumor microenvironment to facilitate aberrant aerobic glycolysis via activating LPA/LPAR axis and maintaining ALDOA stability, which provides an actionable gemcitabine-based combination therapy with limited side effects.
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Affiliation(s)
- Lijie Han
- Department of General Surgery, Pancreatic Disease Center, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, 197 Ruijin 2Nd Road, Shanghai, 200025, China
- Research Institute of Pancreatic Diseases, Shanghai Jiaotong University School of Medicine, Shanghai, China
- State Key Laboratory of Oncogenes and Related Genes, Shanghai, China
| | - Yongsheng Jiang
- Department of General Surgery, Pancreatic Disease Center, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, 197 Ruijin 2Nd Road, Shanghai, 200025, China
- Research Institute of Pancreatic Diseases, Shanghai Jiaotong University School of Medicine, Shanghai, China
- State Key Laboratory of Oncogenes and Related Genes, Shanghai, China
| | - Minmin Shi
- Department of General Surgery, Pancreatic Disease Center, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, 197 Ruijin 2Nd Road, Shanghai, 200025, China
- Research Institute of Pancreatic Diseases, Shanghai Jiaotong University School of Medicine, Shanghai, China
- State Key Laboratory of Oncogenes and Related Genes, Shanghai, China
| | - Lina Gan
- Department of General Surgery, Pancreatic Disease Center, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, 197 Ruijin 2Nd Road, Shanghai, 200025, China
- Research Institute of Pancreatic Diseases, Shanghai Jiaotong University School of Medicine, Shanghai, China
- State Key Laboratory of Oncogenes and Related Genes, Shanghai, China
| | - Zhichong Wu
- Department of General Surgery, Pancreatic Disease Center, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, 197 Ruijin 2Nd Road, Shanghai, 200025, China
- Research Institute of Pancreatic Diseases, Shanghai Jiaotong University School of Medicine, Shanghai, China
- State Key Laboratory of Oncogenes and Related Genes, Shanghai, China
| | - Meilin Xue
- Department of General Surgery, Pancreatic Disease Center, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, 197 Ruijin 2Nd Road, Shanghai, 200025, China
- Research Institute of Pancreatic Diseases, Shanghai Jiaotong University School of Medicine, Shanghai, China
- State Key Laboratory of Oncogenes and Related Genes, Shanghai, China
| | - Youwei Zhu
- Department of General Surgery, Pancreatic Disease Center, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, 197 Ruijin 2Nd Road, Shanghai, 200025, China
- Research Institute of Pancreatic Diseases, Shanghai Jiaotong University School of Medicine, Shanghai, China
- State Key Laboratory of Oncogenes and Related Genes, Shanghai, China
| | - Cheng Xiong
- Department of General Surgery, Pancreatic Disease Center, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, 197 Ruijin 2Nd Road, Shanghai, 200025, China
- Research Institute of Pancreatic Diseases, Shanghai Jiaotong University School of Medicine, Shanghai, China
- State Key Laboratory of Oncogenes and Related Genes, Shanghai, China
| | - Ting Wang
- Department of Pathology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Xiaozhu Lin
- Department of Nuclear Medicine, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, 197 Ruijin 2Nd Road, Shanghai, China
| | - Baiyong Shen
- Department of General Surgery, Pancreatic Disease Center, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, 197 Ruijin 2Nd Road, Shanghai, 200025, China.
- Research Institute of Pancreatic Diseases, Shanghai Jiaotong University School of Medicine, Shanghai, China.
- State Key Laboratory of Oncogenes and Related Genes, Shanghai, China.
- Institute of Translational Medicine, Shanghai Jiaotong University, Shanghai, China.
| | - Lingxi Jiang
- Department of General Surgery, Pancreatic Disease Center, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, 197 Ruijin 2Nd Road, Shanghai, 200025, China.
- Research Institute of Pancreatic Diseases, Shanghai Jiaotong University School of Medicine, Shanghai, China.
- State Key Laboratory of Oncogenes and Related Genes, Shanghai, China.
| | - Hao Chen
- Department of General Surgery, Pancreatic Disease Center, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, 197 Ruijin 2Nd Road, Shanghai, 200025, China.
- Research Institute of Pancreatic Diseases, Shanghai Jiaotong University School of Medicine, Shanghai, China.
- State Key Laboratory of Oncogenes and Related Genes, Shanghai, China.
- Institute of Translational Medicine, Shanghai Jiaotong University, Shanghai, China.
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Du B, Zhang F, Zhou Q, Cheng W, Yu Z, Li L, Yang J, Zhang X, Zhou C, Zhang W. Joint analysis of the metabolomics and transcriptomics uncovers the dysregulated network and develops the diagnostic model of high-risk neuroblastoma. Sci Rep 2023; 13:16991. [PMID: 37813883 PMCID: PMC10562375 DOI: 10.1038/s41598-023-43988-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2023] [Accepted: 10/01/2023] [Indexed: 10/11/2023] Open
Abstract
High-risk neuroblastoma (HR-NB) has a significantly lower survival rate compared to low- and intermediate-risk NB (LIR-NB) due to the lack of risk classification diagnostic models and effective therapeutic targets. The present study aims to characterize the differences between neuroblastomas with different risks through transcriptomic and metabolomic, and establish an early diagnostic model for risk classification of neuroblastoma.Plasma samples from 58 HR-NB and 38 LIR-NB patients were used for metabolomics analysis. Meanwhile, NB tissue samples from 32 HR-NB and 23 LIR-NB patients were used for transcriptomics analysis. In particular, integrative metabolomics and transcriptomic analysis was performed between HR-NB and LIR-NB. A total of 44 metabolites (P < 0.05 and fold change > 1.5) were altered, including 12 that increased and 32 that decreased in HR-NB. A total of 1,408 mRNAs (P < 0.05 and |log2(fold change)|> 1) showed significantly altered in HR-NB, of which 1,116 were upregulated and 292 were downregulated. Joint analysis of both omic data identified 4 aberrant pathways (P < 0.05 and impact ≥ 0.5) consisting of glycerolipid metabolism, retinol metabolism, arginine biosynthesis and linoleic acid metabolism. Importantly, a HR-NB risk classification diagnostic model was developed using plasma circulating-free S100A9, CDK2, and UNC5D, with an area under receiver operating characteristic curve of 0.837 where the sensitivity and specificity in the validation set were both 80.0%. This study presents a novel pioneering study demonstrating the metabolomics and transcriptomics profiles of HR-NB. The glycerolipid metabolism, retinol metabolism, arginine biosynthesis and linoleic acid metabolism were altered in HR-NB. The risk classification diagnostic model based on S100A9, CDK2, and UNC5D can be clinically used for HR-NB risk classification.
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Affiliation(s)
- Bang Du
- Henan Key Laboratory of Children's Genetics and Metabolic Diseases, Children's Hospital Affiliated to Zhengzhou University, Henan Children's Hospital, Zhengzhou, 450018, China
- Henan International Joint Laboratory for Prevention and Treatment of Pediatric Disease, Children's Hospital Affiliated to Zhengzhou University, Henan Children's Hospital, Zhengzhou, 450018, China
- Health Commission of Henan Province Key Laboratory for Precision Diagnosis and Treatment of Pediatric Tumor, Children's Hospital Affiliated to Zhengzhou University, Henan Children's Hospital, Zhengzhou, 450018, China
| | - Fei Zhang
- Henan Key Laboratory of Children's Genetics and Metabolic Diseases, Children's Hospital Affiliated to Zhengzhou University, Henan Children's Hospital, Zhengzhou, 450018, China
- Henan International Joint Laboratory for Prevention and Treatment of Pediatric Disease, Children's Hospital Affiliated to Zhengzhou University, Henan Children's Hospital, Zhengzhou, 450018, China
- Health Commission of Henan Province Key Laboratory for Precision Diagnosis and Treatment of Pediatric Tumor, Children's Hospital Affiliated to Zhengzhou University, Henan Children's Hospital, Zhengzhou, 450018, China
| | - Qiumei Zhou
- Experimental Center of Clinical Research, The First Affiliated Hospital of Anhui University of Chinese Medicine, Hefei, 230000, China
| | - Weyland Cheng
- Henan Key Laboratory of Children's Genetics and Metabolic Diseases, Children's Hospital Affiliated to Zhengzhou University, Henan Children's Hospital, Zhengzhou, 450018, China
- Henan International Joint Laboratory for Prevention and Treatment of Pediatric Disease, Children's Hospital Affiliated to Zhengzhou University, Henan Children's Hospital, Zhengzhou, 450018, China
- Health Commission of Henan Province Key Laboratory for Precision Diagnosis and Treatment of Pediatric Tumor, Children's Hospital Affiliated to Zhengzhou University, Henan Children's Hospital, Zhengzhou, 450018, China
| | - Zhidan Yu
- Henan Key Laboratory of Children's Genetics and Metabolic Diseases, Children's Hospital Affiliated to Zhengzhou University, Henan Children's Hospital, Zhengzhou, 450018, China
- Henan International Joint Laboratory for Prevention and Treatment of Pediatric Disease, Children's Hospital Affiliated to Zhengzhou University, Henan Children's Hospital, Zhengzhou, 450018, China
- Health Commission of Henan Province Key Laboratory for Precision Diagnosis and Treatment of Pediatric Tumor, Children's Hospital Affiliated to Zhengzhou University, Henan Children's Hospital, Zhengzhou, 450018, China
| | - Lifeng Li
- Henan Key Laboratory of Children's Genetics and Metabolic Diseases, Children's Hospital Affiliated to Zhengzhou University, Henan Children's Hospital, Zhengzhou, 450018, China
- Henan International Joint Laboratory for Prevention and Treatment of Pediatric Disease, Children's Hospital Affiliated to Zhengzhou University, Henan Children's Hospital, Zhengzhou, 450018, China
- Health Commission of Henan Province Key Laboratory for Precision Diagnosis and Treatment of Pediatric Tumor, Children's Hospital Affiliated to Zhengzhou University, Henan Children's Hospital, Zhengzhou, 450018, China
| | - Jianwei Yang
- Henan Key Laboratory of Children's Genetics and Metabolic Diseases, Children's Hospital Affiliated to Zhengzhou University, Henan Children's Hospital, Zhengzhou, 450018, China
- Henan International Joint Laboratory for Prevention and Treatment of Pediatric Disease, Children's Hospital Affiliated to Zhengzhou University, Henan Children's Hospital, Zhengzhou, 450018, China
- Health Commission of Henan Province Key Laboratory for Precision Diagnosis and Treatment of Pediatric Tumor, Children's Hospital Affiliated to Zhengzhou University, Henan Children's Hospital, Zhengzhou, 450018, China
| | - Xianwei Zhang
- Henan Key Laboratory of Children's Genetics and Metabolic Diseases, Children's Hospital Affiliated to Zhengzhou University, Henan Children's Hospital, Zhengzhou, 450018, China.
- Henan International Joint Laboratory for Prevention and Treatment of Pediatric Disease, Children's Hospital Affiliated to Zhengzhou University, Henan Children's Hospital, Zhengzhou, 450018, China.
- Health Commission of Henan Province Key Laboratory for Precision Diagnosis and Treatment of Pediatric Tumor, Children's Hospital Affiliated to Zhengzhou University, Henan Children's Hospital, Zhengzhou, 450018, China.
| | - Chongchen Zhou
- Henan Key Laboratory of Children's Genetics and Metabolic Diseases, Children's Hospital Affiliated to Zhengzhou University, Henan Children's Hospital, Zhengzhou, 450018, China.
- Henan International Joint Laboratory for Prevention and Treatment of Pediatric Disease, Children's Hospital Affiliated to Zhengzhou University, Henan Children's Hospital, Zhengzhou, 450018, China.
- Health Commission of Henan Province Key Laboratory for Precision Diagnosis and Treatment of Pediatric Tumor, Children's Hospital Affiliated to Zhengzhou University, Henan Children's Hospital, Zhengzhou, 450018, China.
| | - Wancun Zhang
- Henan Key Laboratory of Children's Genetics and Metabolic Diseases, Children's Hospital Affiliated to Zhengzhou University, Henan Children's Hospital, Zhengzhou, 450018, China.
- Henan International Joint Laboratory for Prevention and Treatment of Pediatric Disease, Children's Hospital Affiliated to Zhengzhou University, Henan Children's Hospital, Zhengzhou, 450018, China.
- Health Commission of Henan Province Key Laboratory for Precision Diagnosis and Treatment of Pediatric Tumor, Children's Hospital Affiliated to Zhengzhou University, Henan Children's Hospital, Zhengzhou, 450018, China.
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3
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Shahari MSB, Dolzhenko AV. A closer look at N2,6-substituted 1,3,5-triazine-2,4-diamines: Advances in synthesis and biological activities. Eur J Med Chem 2022; 241:114645. [DOI: 10.1016/j.ejmech.2022.114645] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Revised: 07/19/2022] [Accepted: 07/29/2022] [Indexed: 11/03/2022]
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4
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Karagiota A, Chachami G, Paraskeva E. Lipid Metabolism in Cancer: The Role of Acylglycerolphosphate Acyltransferases (AGPATs). Cancers (Basel) 2022; 14:cancers14010228. [PMID: 35008394 PMCID: PMC8750616 DOI: 10.3390/cancers14010228] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Revised: 12/28/2021] [Accepted: 12/31/2021] [Indexed: 12/13/2022] Open
Abstract
Simple Summary Rapidly proliferating cancer cells reprogram lipid metabolism to keep the balance between fatty acid uptake, synthesis, consumption, and storage as triacylglycerides (TAG). Acylglycerolphosphate acyltransferases (AGPATs)/lysophosphatidic acid acyltransferases (LPAATs) are a family of enzymes that catalyze the synthesis of phosphatidic acid (PA), an intermediate in TAG synthesis, a signaling molecule, and a precursor of phospholipids. Importantly, the expression of AGPATs has been linked to diverse physiological and pathological phenotypes, including cancer. In this review, we present an overview of lipid metabolism reprogramming in cancer cells and give insight into the expression of AGPAT isoforms as well as their association with cancers, parameters of tumor biology, patient classification, and prognosis. Abstract Altered lipid metabolism is an emerging hallmark of aggressive tumors, as rapidly proliferating cancer cells reprogram fatty acid (FA) uptake, synthesis, storage, and usage to meet their increased energy demands. Central to these adaptive changes, is the conversion of excess FA to neutral triacylglycerides (TAG) and their storage in lipid droplets (LDs). Acylglycerolphosphate acyltransferases (AGPATs), also known as lysophosphatidic acid acyltransferases (LPAATs), are a family of five enzymes that catalyze the conversion of lysophosphatidic acid (LPA) to phosphatidic acid (PA), the second step of the TAG biosynthesis pathway. PA, apart from its role as an intermediate in TAG synthesis, is also a precursor of glycerophospholipids and a cell signaling molecule. Although the different AGPAT isoforms catalyze the same reaction, they appear to have unique non-overlapping roles possibly determined by their distinct tissue expression and substrate specificity. This is best exemplified by the role of AGPAT2 in the development of type 1 congenital generalized lipodystrophy (CGL) and is also manifested by recent studies highlighting the involvement of AGPATs in the physiology and pathology of various tissues and organs. Importantly, AGPAT isoform expression has been shown to enhance proliferation and chemoresistance of cancer cells and correlates with increased risk of tumor development or aggressive phenotypes of several types of tumors.
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Affiliation(s)
- Angeliki Karagiota
- Laboratory of Biochemistry, Faculty of Medicine, University of Thessaly, BIOPOLIS, 41500 Larissa, Greece; (A.K.); (G.C.)
- Laboratory of Physiology, Faculty of Medicine, University of Thessaly, BIOPOLIS, 41500 Larissa, Greece
| | - Georgia Chachami
- Laboratory of Biochemistry, Faculty of Medicine, University of Thessaly, BIOPOLIS, 41500 Larissa, Greece; (A.K.); (G.C.)
| | - Efrosyni Paraskeva
- Laboratory of Physiology, Faculty of Medicine, University of Thessaly, BIOPOLIS, 41500 Larissa, Greece
- Correspondence:
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5
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Jiang SL, Fang DA, Xu DP. Transcriptome changes of Takifugu obscurus liver after acute exposure to phenanthrene. Physiol Genomics 2021; 53:116-124. [PMID: 33459152 DOI: 10.1152/physiolgenomics.00100.2020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Phenanthrene (Phe) is a model compound in polycyclic aromatic hydrocarbon (PAH) research. Reportedly, Phe treatment induced oxidative stress and histological disorders to Takifugu obscurus liver. In this study, to further explore the molecular responses of T. obscurus liver to Phe exposure, transcriptome sequencing was applied to compare mRNA transcription profiles between Phe treatment and the control. Compared with the control, 1,581 and 1,428 genes were significantly upregulated and downregulated in Phe treatment, respectively. Further analysis revealed that Phe treatment mainly upregulated genes in Ras-MAPK and PI3K-akt signaling pathways, which represented insulin resistance and further activated the FOXO signaling pathway. The triacylglycerol biosynthesis was promoted but the gluconeogenesis process was inhibited in response to Phe treatment, demonstrating that Phe exposure disturbed the sugar and lipid metabolism. Moreover, Phe treatment upregulated the Apelin-APJ and ErbB signaling pathways, promoting angiogenesis in T. obscurus liver. Insulin resistance, promoted triacylglycerol biosynthesis, and angiogenesis might explain the molecular mechanisms underlying carcinogenic toxicity of Phe. Overall, this study provides new insights to understand the environmental risk of Phe to fishes.
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Affiliation(s)
- Shu-Lun Jiang
- Wuxi Fisheries College, Nanjing Agricultural University, Wuxi, China
| | - Di-An Fang
- Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, China
| | - Dong-Po Xu
- Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, China
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6
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Junaid A, Lim FPL, Tiekink ERT, Dolzhenko AV. New One-Pot Synthesis of 1,3,5-Triazines: Three-Component Condensation, Dimroth Rearrangement, and Dehydrogenative Aromatization. ACS COMBINATORIAL SCIENCE 2019; 21:548-555. [PMID: 31180634 DOI: 10.1021/acscombsci.9b00079] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A new, effective one-pot synthesis of the 6, N2-diaryl-1,3,5-triazine-2,4-diamines under microwave irradiation was developed. The method involved an initial three-component condensation of cyanoguanidine, aromatic aldehydes, and arylamines in the presence of hydrochloric acid. Without isolation, the resulting 1,6-diaryl-1,6-dihydro-1,3,5-triazine-2,4-diamines were treated with a base to initiate Dimroth rearrangement and spontaneous dehydrogenative aromatization, affording the desired compounds. The developed method was found to be sufficiently general in scope, tolerating various aromatic aldehydes and amines; by using their combinations in the first step, a representative library of 110 compounds was successfully prepared and screened for anticancer properties.
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Affiliation(s)
- Ahmad Junaid
- School of Pharmacy, Monash University Malaysia, Jalan Lagoon Selatan, Bandar Sunway, Selangor Darul Ehsan 47500, Malaysia
| | - Felicia Phei Lin Lim
- School of Pharmacy, Monash University Malaysia, Jalan Lagoon Selatan, Bandar Sunway, Selangor Darul Ehsan 47500, Malaysia
| | - Edward R. T. Tiekink
- Research Centre for Crystalline Materials, School of Science and Technology, Sunway University, 5 Jalan Universiti, Bandar Sunway, Selangor Darul Ehsan 47500, Malaysia
| | - Anton V. Dolzhenko
- School of Pharmacy, Monash University Malaysia, Jalan Lagoon Selatan, Bandar Sunway, Selangor Darul Ehsan 47500, Malaysia
- School of Pharmacy and Biomedical Sciences, Curtin Health Innovation Research Institute, Faculty of Health Sciences, Curtin University, GPO Box U1987, Perth, Western Australia 6845, Australia
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7
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Poirier M, Awale M, Roelli MA, Giuffredi GT, Ruddigkeit L, Evensen L, Stooss A, Calarco S, Lorens JB, Charles RP, Reymond JL. Identifying Lysophosphatidic Acid Acyltransferase β (LPAAT-β) as the Target of a Nanomolar Angiogenesis Inhibitor from a Phenotypic Screen Using the Polypharmacology Browser PPB2. ChemMedChem 2018; 14:224-236. [PMID: 30520265 DOI: 10.1002/cmdc.201800554] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2018] [Indexed: 12/11/2022]
Abstract
By screening a focused library of kinase inhibitor analogues in a phenotypic co-culture assay for angiogenesis inhibition, we identified an aminotriazine that acts as a cytostatic nanomolar inhibitor. However, this aminotriazine was found to be completely inactive in a whole-kinome profiling assay. To decipher its mechanism of action, we used the online target prediction tool PPB2 (http://ppb2.gdb.tools), which suggested lysophosphatidic acid acyltransferase β (LPAAT-β) as a possible target for this aminotriazine as well as several analogues identified by structure-activity relationship profiling. LPAAT-β inhibition (IC50 ≈15 nm) was confirmed in a biochemical assay and by its effects on cell proliferation in comparison with a known LPAAT-β inhibitor. These experiments illustrate the value of target-prediction tools to guide target identification for phenotypic screening hits and significantly expand the rather limited pharmacology of LPAAT-β inhibitors.
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Affiliation(s)
- Marion Poirier
- Department of Chemistry and Biochemistry, National Center of Competence in Research NCCR TransCure, University of Bern, Freiestrasse 3, 3012, Bern, Switzerland
| | - Mahendra Awale
- Department of Chemistry and Biochemistry, National Center of Competence in Research NCCR TransCure, University of Bern, Freiestrasse 3, 3012, Bern, Switzerland
| | - Matthias A Roelli
- Institute of Biochemistry and Molecular Medicine, National Center of Competence in Research NCCR TransCure, University of Bern, Bühlstrasse 28, 3000, Bern 9, Switzerland
| | - Guy T Giuffredi
- Department of Chemistry and Biochemistry, National Center of Competence in Research NCCR TransCure, University of Bern, Freiestrasse 3, 3012, Bern, Switzerland
| | - Lars Ruddigkeit
- Department of Chemistry and Biochemistry, National Center of Competence in Research NCCR TransCure, University of Bern, Freiestrasse 3, 3012, Bern, Switzerland
| | - Lasse Evensen
- Department of Biomedicine, Centre for Cancer Biomarkers (CCBIO), University of Bergen, Jonas Lies vei 91, 5009, Bergen, Norway
| | - Amandine Stooss
- Institute of Biochemistry and Molecular Medicine, National Center of Competence in Research NCCR TransCure, University of Bern, Bühlstrasse 28, 3000, Bern 9, Switzerland
| | - Serafina Calarco
- Institute of Biochemistry and Molecular Medicine, National Center of Competence in Research NCCR TransCure, University of Bern, Bühlstrasse 28, 3000, Bern 9, Switzerland
| | - James B Lorens
- Department of Biomedicine, Centre for Cancer Biomarkers (CCBIO), University of Bergen, Jonas Lies vei 91, 5009, Bergen, Norway
| | - Roch-Philippe Charles
- Institute of Biochemistry and Molecular Medicine, National Center of Competence in Research NCCR TransCure, University of Bern, Bühlstrasse 28, 3000, Bern 9, Switzerland
| | - Jean-Louis Reymond
- Department of Chemistry and Biochemistry, National Center of Competence in Research NCCR TransCure, University of Bern, Freiestrasse 3, 3012, Bern, Switzerland
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8
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Sahoo S, Ravi Kumar RK, Nicolay B, Mohite O, Sivaraman K, Khetan V, Rishi P, Ganesan S, Subramanyan K, Raman K, Miles W, Elchuri SV. Metabolite systems profiling identifies exploitable weaknesses in retinoblastoma. FEBS Lett 2018; 593:23-41. [PMID: 30417337 DOI: 10.1002/1873-3468.13294] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Revised: 09/25/2018] [Accepted: 11/06/2018] [Indexed: 11/06/2022]
Abstract
Retinoblastoma (RB) is a childhood eye cancer. Currently, chemotherapy, local therapy, and enucleation are the main ways in which these tumors are managed. The present work is the first study that uses constraint-based reconstruction and analysis approaches to identify and explain RB-specific survival strategies, which are RB tumor specific. Importantly, our model-specific secretion profile is also found in RB1-depleted human retinal cells in vitro and suggests that novel biomarkers involved in lipid metabolism may be important. Finally, RB-specific synthetic lethals have been predicted as lipid and nucleoside transport proteins that can aid in novel drug target development.
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Affiliation(s)
- Swagatika Sahoo
- Department of Chemical Engineering, Indian Institute of Technology Madras, Chennai, India.,Initiative for Biological Systems Engineering, Indian Institute of Technology Madras, Chennai, India
| | | | - Brandon Nicolay
- Department of Molecular Oncology, Massachusetts General Hospital Cancer Center and Harvard Medical School, Charlestown, MA, USA.,Agios Pharmaceutical, 88 Sidney Street, Cambridge, MA, USA
| | - Omkar Mohite
- Initiative for Biological Systems Engineering, Indian Institute of Technology Madras, Chennai, India.,Department of Biotechnology, Bhupat and Jyoti Mehta School of Biosciences, Indian Institute of Technology Madras, Chennai, India.,The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kongens Lyngby, Denmark
| | | | - Vikas Khetan
- Shri Bhagwan Mahavir Vitreoretinal Services and Ocular Oncology Services, Sankara Nethralaya, Chennai, India
| | - Pukhraj Rishi
- Shri Bhagwan Mahavir Vitreoretinal Services and Ocular Oncology Services, Sankara Nethralaya, Chennai, India
| | - Suganeswari Ganesan
- Department of Histopathology, Vision Research Foundation, Sankara Nethralaya, Chennai, India
| | | | - Karthik Raman
- Initiative for Biological Systems Engineering, Indian Institute of Technology Madras, Chennai, India.,Department of Biotechnology, Bhupat and Jyoti Mehta School of Biosciences, Indian Institute of Technology Madras, Chennai, India.,Robert Bosch Centre for Data Science and Artificial Intelligence (RBC-DSAI), Indian Institute of Technology Madras, Chennai, India
| | - Wayne Miles
- Department of Molecular Oncology, Massachusetts General Hospital Cancer Center and Harvard Medical School, Charlestown, MA, USA.,Department of Molecular Genetics, The Ohio State University Comprehensive Cancer Center, The Ohio State University, Columbus, OH, USA
| | - Sailaja V Elchuri
- Department of Nanotechnology, Vision Research Foundation, Sankara Nethralaya, Chennai, India
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9
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Repetto-Llamazares AHV, Malenge MM, O'Shea A, Eiríksdóttir B, Stokke T, Larsen RH, Dahle J. Combination of177Lu-lilotomab with rituximab significantly improves the therapeutic outcome in preclinical models of non-Hodgkin's lymphoma. Eur J Haematol 2018; 101:522-531. [DOI: 10.1111/ejh.13139] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Accepted: 07/05/2018] [Indexed: 12/13/2022]
Affiliation(s)
| | - Marion M. Malenge
- Nordic Nanovector ASA; Oslo Norway
- Department of Radiation Biology; Institute for Cancer Research; Oslo University Hospital; Oslo Norway
- Institute of Clinical Medicine; Faculty of Medicine; University of Oslo; Oslo Norway
| | | | | | - Trond Stokke
- Department of Radiation Biology; Institute for Cancer Research; Oslo University Hospital; Oslo Norway
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Triantafyllou EA, Georgatsou E, Mylonis I, Simos G, Paraskeva E. Expression of AGPAT2, an enzyme involved in the glycerophospholipid/triacylglycerol biosynthesis pathway, is directly regulated by HIF-1 and promotes survival and etoposide resistance of cancer cells under hypoxia. Biochim Biophys Acta Mol Cell Biol Lipids 2018; 1863:1142-1152. [PMID: 29908837 DOI: 10.1016/j.bbalip.2018.06.015] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2018] [Revised: 05/22/2018] [Accepted: 06/12/2018] [Indexed: 02/07/2023]
Abstract
Hypoxia inducible factor-1 (HIF-1) supports survival of normal cells under low oxygen concentration and cancer cells in the hypoxic tumor microenvironment. This involves metabolic reprogramming via upregulation of glycolysis, downregulation of oxidative phosphorylation and, less well documented, effects on lipid metabolism. To investigate the latter, we examined expression of relevant enzymes in cancer cells grown under hypoxia. We show that expression of acylglycerol-3-phosphate acyltransferase 2 (AGPAT2), also known as lysophosphatidic acid acyltransferase β (LPAATβ), was upregulated under hypoxia and this was impaired by siRNA-mediated knockdown of HIF-1α. Moreover, a sequence of the AGPAT2 gene promoter region, containing 6 putative Hypoxia Response Elements (HREs), activated transcription of a reporter gene under hypoxic conditions or in normoxic cells over-expressing HIF-1α. Chromatin immunoprecipitation experiments confirmed binding of HIF-1α to one of these HREs, mutation of which abolished hypoxic activation of the AGPAT2 promoter. Knockdown of AGPAT2 by siRNA reduced lipid droplet accumulation and cell viability under hypoxia and increased cancer cell sensitivity to the chemotherapeutic etoposide. In conclusion, our findings demonstrate that AGPAT2, which is mutated in patients with congenital generalized lipodystrophy and over-expressed in different types of cancer, is a direct transcriptional target of HIF-1, suggesting that upregulation of lipid storage by HIF-1 plays an important role in adaptation and survival of cancer cells under low oxygen conditions.
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Affiliation(s)
| | - Eleni Georgatsou
- Laboratory of Biochemistry, Faculty of Medicine, University of Thessaly, Larissa, Greece
| | - Ilias Mylonis
- Laboratory of Biochemistry, Faculty of Medicine, University of Thessaly, Larissa, Greece
| | - George Simos
- Laboratory of Biochemistry, Faculty of Medicine, University of Thessaly, Larissa, Greece; Gerald Bronfman Department of Oncology, Faculty of Medicine, McGill University, Montreal, Canada
| | - Efrosyni Paraskeva
- Laboratory of Physiology, Faculty of Medicine, University of Thessaly, Larissa, Greece.
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11
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Song L, Duan P, Gan Y, Li P, Zhao C, Xu J, Zhang Z, Zhou Q. Silencing LPAATβ inhibits tumor growth of cisplatin-resistant human osteosarcoma in vivo and in vitro. Int J Oncol 2016; 50:535-544. [DOI: 10.3892/ijo.2016.3820] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Accepted: 12/06/2016] [Indexed: 11/06/2022] Open
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12
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Safdari Y, Ahmadzadeh V, Farajnia S. CD20-targeting in B-cell malignancies: novel prospects for antibodies and combination therapies. Invest New Drugs 2016; 34:497-512. [DOI: 10.1007/s10637-016-0349-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Accepted: 03/22/2016] [Indexed: 12/13/2022]
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13
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Yamashita A, Hayashi Y, Matsumoto N, Nemoto-Sasaki Y, Oka S, Tanikawa T, Sugiura T. Glycerophosphate/Acylglycerophosphate acyltransferases. BIOLOGY 2014; 3:801-30. [PMID: 25415055 PMCID: PMC4280512 DOI: 10.3390/biology3040801] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Revised: 11/02/2014] [Accepted: 11/05/2014] [Indexed: 11/16/2022]
Abstract
Acyl-CoA:glycerol-3-phosphate acyltransferase (GPAT) and acyl-CoA: 1-acyl-glycerol-3-phosphate acyltransferase (AGPAT) are involved in the de novo synthesis of triacylglycerol (TAG) and glycerophospholipids. Many enzymes belonging to the GPAT/AGPAT family have recently been identified and their physiological or pathophysiological roles have been proposed. The roles of GPAT/AGPAT in the synthesis of TAG and obesity-related diseases were revealed through the identification of causative genes of these diseases or analyses of genetically manipulated animals. Recent studies have suggested that some isoforms of GPAT/AGPAT family enzymes are involved in the fatty acid remodeling of phospholipids. The enzymology of GPAT/AGPAT and their physiological/pathological roles in the metabolism of glycerolipids have been described and discussed in this review.
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Affiliation(s)
- Atsushi Yamashita
- Faculty of Pharma-Sciences, Teikyo University, 2-11-1 Kaga, Itabashi-Ku, Tokyo 173-8605, Japan.
| | - Yasuhiro Hayashi
- Faculty of Pharma-Sciences, Teikyo University, 2-11-1 Kaga, Itabashi-Ku, Tokyo 173-8605, Japan.
| | - Naoki Matsumoto
- Faculty of Pharma-Sciences, Teikyo University, 2-11-1 Kaga, Itabashi-Ku, Tokyo 173-8605, Japan.
| | - Yoko Nemoto-Sasaki
- Faculty of Pharma-Sciences, Teikyo University, 2-11-1 Kaga, Itabashi-Ku, Tokyo 173-8605, Japan.
| | - Saori Oka
- Faculty of Pharma-Sciences, Teikyo University, 2-11-1 Kaga, Itabashi-Ku, Tokyo 173-8605, Japan.
| | - Takashi Tanikawa
- Faculty of Pharma-Sciences, Teikyo University, 2-11-1 Kaga, Itabashi-Ku, Tokyo 173-8605, Japan.
| | - Takayuki Sugiura
- Faculty of Pharma-Sciences, Teikyo University, 2-11-1 Kaga, Itabashi-Ku, Tokyo 173-8605, Japan.
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14
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Scott SA, Mathews TP, Ivanova PT, Lindsley CW, Brown HA. Chemical modulation of glycerolipid signaling and metabolic pathways. Biochim Biophys Acta Mol Cell Biol Lipids 2014; 1841:1060-84. [PMID: 24440821 DOI: 10.1016/j.bbalip.2014.01.009] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2013] [Revised: 01/06/2014] [Accepted: 01/07/2014] [Indexed: 01/04/2023]
Abstract
Thirty years ago, glycerolipids captured the attention of biochemical researchers as novel cellular signaling entities. We now recognize that these biomolecules occupy signaling nodes critical to a number of physiological and pathological processes. Thus, glycerolipid-metabolizing enzymes present attractive targets for new therapies. A number of fields-ranging from neuroscience and cancer to diabetes and obesity-have elucidated the signaling properties of glycerolipids. The biochemical literature teems with newly emerging small molecule inhibitors capable of manipulating glycerolipid metabolism and signaling. This ever-expanding pool of chemical modulators appears daunting to those interested in exploiting glycerolipid-signaling pathways in their model system of choice. This review distills the current body of literature surrounding glycerolipid metabolism into a more approachable format, facilitating the application of small molecule inhibitors to novel systems. This article is part of a Special Issue entitled Tools to study lipid functions.
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Affiliation(s)
- Sarah A Scott
- Department of Pharmacology, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Thomas P Mathews
- Department of Pharmacology, Vanderbilt University Medical Center, Nashville, TN 37232, USA; Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Pavlina T Ivanova
- Department of Pharmacology, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Craig W Lindsley
- Department of Pharmacology, Vanderbilt University Medical Center, Nashville, TN 37232, USA; Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University Medical Center, Nashville, TN 37232, USA; Department of Chemistry, Vanderbilt University, Nashville, TN 37235, USA; Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, TN 37235, USA
| | - H Alex Brown
- Department of Pharmacology, Vanderbilt University Medical Center, Nashville, TN 37232, USA; Department of Biochemistry, Vanderbilt University Medical Center, Nashville, TN 37232, USA; Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, TN 37235, USA.
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15
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Acyltransferases and transacylases that determine the fatty acid composition of glycerolipids and the metabolism of bioactive lipid mediators in mammalian cells and model organisms. Prog Lipid Res 2014; 53:18-81. [DOI: 10.1016/j.plipres.2013.10.001] [Citation(s) in RCA: 160] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2012] [Revised: 07/20/2013] [Accepted: 10/01/2013] [Indexed: 12/21/2022]
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16
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Blaskovich MA, Yendluri V, Lawrence HR, Lawrence NJ, Sebti SM, Springett GM. Lysophosphatidic acid acyltransferase beta regulates mTOR signaling. PLoS One 2013; 8:e78632. [PMID: 24205284 PMCID: PMC3814986 DOI: 10.1371/journal.pone.0078632] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2013] [Accepted: 09/13/2013] [Indexed: 12/22/2022] Open
Abstract
Lysophosphatidic acid acyltransferase (LPAAT-β) is a phosphatidic acid (PA) generating enzyme that plays an essential role in triglyceride synthesis. However, LPAAT-β is now being studied as an important regulator of cell growth and differentiation and as a potential therapeutic target in cancer since PA is necessary for the activity of key proteins such as Raf, PKC-ζ and mTOR. In this report we determine the effect of LPAAT-β silencing with siRNA in pancreatic adenocarcinoma cell lines. We show for the first time that LPAAT-β knockdown inhibits proliferation and anchorage-independent growth of pancreatic cancer cells. This is associated with inhibition of signaling by mTOR as determined by levels of mTORC1- and mTORC2-specific phosphorylation sites on 4E-BP1, S6K and Akt. Since PA regulates the activity of mTOR by modulating its binding to FKBP38, we explored the possibility that LPAAT-β might regulate mTOR by affecting its association with FKBP38. Coimmunoprecipitation studies of FKBP38 with mTOR show increased levels of FKBP38 associated with mTOR when LPAAT-β protein levels are knocked down. Furthermore, depletion of LPAAT-β results in increased Lipin 1 nuclear localization which is associated with increased nuclear eccentricity, a nuclear shape change that is dependent on mTOR, further confirming the ability of LPAAT-β to regulate mTOR function. Our results provide support for the hypothesis that PA generated by LPAAT-β regulates mTOR signaling. We discuss the implications of these findings for using LPAAT-β as a therapeutic target.
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Affiliation(s)
- Michelle A. Blaskovich
- Department of Experimental Therapeutics, H. Lee Moffitt Cancer Center and Research Institute, Tampa, Florida, United States of America
- * E-mail:
| | - Vimala Yendluri
- Department of Experimental Therapeutics, H. Lee Moffitt Cancer Center and Research Institute, Tampa, Florida, United States of America
| | - Harshani R. Lawrence
- Department of Drug Discovery, H. Lee Moffitt Cancer Center and Research Institute, Tampa, Florida, United States of America
- Department of Chemical Biology Core, H. Lee Moffitt Cancer Center and Research Institute, Tampa, Florida, United States of America
- Departments of Oncologic Sciences, University of South Florida, Tampa, Florida, United States of America
| | - Nicholas J. Lawrence
- Department of Drug Discovery, H. Lee Moffitt Cancer Center and Research Institute, Tampa, Florida, United States of America
- Departments of Oncologic Sciences, University of South Florida, Tampa, Florida, United States of America
| | - Saïd M. Sebti
- Department of Drug Discovery, H. Lee Moffitt Cancer Center and Research Institute, Tampa, Florida, United States of America
- Departments of Oncologic Sciences, University of South Florida, Tampa, Florida, United States of America
- Molecular Medicine, University of South Florida, Tampa, Florida, United States of America
| | - Gregory M. Springett
- Department of Experimental Therapeutics, H. Lee Moffitt Cancer Center and Research Institute, Tampa, Florida, United States of America
- Department of Drug Discovery, H. Lee Moffitt Cancer Center and Research Institute, Tampa, Florida, United States of America
- Department of Gastrointestinal Oncology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, Florida, United States of America
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17
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Castellanos-Gonzalez A, White AC, Ojo KK, Vidadala RSR, Zhang Z, Reid MC, Fox AMW, Keyloun KR, Rivas K, Irani A, Dann SM, Fan E, Maly DJ, Van Voorhis WC. A novel calcium-dependent protein kinase inhibitor as a lead compound for treating cryptosporidiosis. J Infect Dis 2013; 208:1342-8. [PMID: 23878324 DOI: 10.1093/infdis/jit327] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Cryptosporidium parasites infect intestinal cells, causing cryptosporidiosis. Despite its high morbidity and association with stunting in the developing world, current therapies for cryptosporidiosis have limited efficacy. Calcium-dependent protein kinases (CDPKs) are essential enzymes in the biology of protozoan parasites. CDPK1 was cloned from the genome of Cryptosporidium parvum, and potent and specific inhibitors have been developed based on structural studies. In this study, we evaluated the anti-Cryptosporidium activity of a novel CDPK1 inhibitor, 1294, and demonstrated that 1294 significantly reduces parasite infection in vitro, with a half maximal effective concentration of 100 nM. Pharmacokinetic studies revealed that 1294 is well absorbed, with a half-life supporting daily administration. Oral therapy with 1294 eliminated Cryptosporidium parasites from 6 of 7 infected severe combined immunodeficiency-beige mice, and the parasites did not recur in these immunosuppressed mice. Mice treated with 1294 had less epithelial damage, corresponding to less apoptosis. Thus, 1294 is an important lead for the development of drugs for treatment of cryptosporidiosis.
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18
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Ridgway ND. The role of phosphatidylcholine and choline metabolites to cell proliferation and survival. Crit Rev Biochem Mol Biol 2013; 48:20-38. [PMID: 23350810 DOI: 10.3109/10409238.2012.735643] [Citation(s) in RCA: 206] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The reorganization of metabolic pathways in cancer facilitates the flux of carbon and reducing equivalents into anabolic pathways at the expense of oxidative phosphorylation. This provides rapidly dividing cells with the necessary precursors for membrane, protein and nucleic acid synthesis. A fundamental metabolic perturbation in cancer is the enhanced synthesis of fatty acids by channeling glucose and/or glutamine into cytosolic acetyl-CoA and upregulation of key biosynthetic genes. This lipogenic phenotype also extends to the production of complex lipids involved in membrane synthesis and lipid-based signaling. Cancer cells display sensitivity to ablation of fatty acid synthesis possibly as a result of diminished capacity to synthesize complex lipids involved in signaling or growth pathways. Evidence has accrued that phosphatidylcholine, the major phospholipid component of eukaryotic membranes, as well as choline metabolites derived from its synthesis and catabolism, contribute to both proliferative growth and programmed cell death. This review will detail our current understanding of how coordinated changes in substrate availability, gene expression and enzyme activity lead to altered phosphatidylcholine synthesis in cancer, and how these changes contribute directly or indirectly to malignant growth. Conversely, apoptosis targets key steps in phosphatidylcholine synthesis and degradation that are linked to disruption of cell cycle regulation, reinforcing the central role that phosphatidylcholine and its metabolites in determining cell fate.
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Affiliation(s)
- Neale D Ridgway
- Departments of Pediatrics and Biochemistry & Molecular Biology, The Atlantic Research Centre, Dalhousie University, Halifax, Nova Scotia Canada.
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19
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Song L, Yang J, Duan P, Xu J, Luo X, Luo F, Zhang Z, Hou T, Liu B, Zhou Q. MicroRNA-24 inhibits osteosarcoma cell proliferation both in vitro and in vivo by targeting LPAATβ. Arch Biochem Biophys 2013; 535:128-35. [DOI: 10.1016/j.abb.2013.04.001] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2013] [Revised: 03/18/2013] [Accepted: 04/01/2013] [Indexed: 11/26/2022]
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20
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Bezombes C, Fournié JJ, Laurent G. Direct Effect of Rituximab in B-Cell–Derived Lymphoid Neoplasias: Mechanism, Regulation, and Perspectives. Mol Cancer Res 2011; 9:1435-42. [DOI: 10.1158/1541-7786.mcr-11-0154] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
The anti-CD20 monoclonal antibody rituximab is the backbone of treatment for the B-cell malignancies non-Hodgkin lymphoma and chronic lymphocytic leukemia. However, there is a wide variability in response to rituximab treatment, and some patients are refractory to current standard therapies. Rituximab kills B cells by multiple mechanisms of action, including complement-dependent cytotoxicity and antibody-dependent cellular cytotoxicity, which are immune-mediated mechanisms, as well as by direct effects on cell signaling pathways and cell membranes following CD20 binding. A large number of events that are affected by rituximab binding have been identified, including lipid raft modifications, kinase and caspase activation, and effects on transcription factors and apoptotic/antiapoptotic molecules. Studies on cell lines and isolated tumor cells have shown that by targeting these pathways, it may be possible to increase or decrease susceptibility to rituximab cell killing. An increased understanding of the direct effects of rituximab may therefore aid in the design of new, rational combinations to improve the outcome of CD20-based therapy for patients who currently have suboptimal outcome following standard treatments. Mol Cancer Res; 9(11); 1435–42. ©2011 AACR.
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Affiliation(s)
- Christine Bezombes
- Authors' Affiliations: 1Cancer Research Center of Toulouse, Institut National de la Santé et de la Recherche Médicale, UMR1037-Centre National de la Recherche Scientifique ERL5294, Université Toulouse 3 BP3028; 2Service Hématologie, Centre Hospitalier Universitaire de Toulouse, Hôpital Purpan, Toulouse, France
| | - Jean-Jacques Fournié
- Authors' Affiliations: 1Cancer Research Center of Toulouse, Institut National de la Santé et de la Recherche Médicale, UMR1037-Centre National de la Recherche Scientifique ERL5294, Université Toulouse 3 BP3028; 2Service Hématologie, Centre Hospitalier Universitaire de Toulouse, Hôpital Purpan, Toulouse, France
| | - Guy Laurent
- Authors' Affiliations: 1Cancer Research Center of Toulouse, Institut National de la Santé et de la Recherche Médicale, UMR1037-Centre National de la Recherche Scientifique ERL5294, Université Toulouse 3 BP3028; 2Service Hématologie, Centre Hospitalier Universitaire de Toulouse, Hôpital Purpan, Toulouse, France
- Authors' Affiliations: 1Cancer Research Center of Toulouse, Institut National de la Santé et de la Recherche Médicale, UMR1037-Centre National de la Recherche Scientifique ERL5294, Université Toulouse 3 BP3028; 2Service Hématologie, Centre Hospitalier Universitaire de Toulouse, Hôpital Purpan, Toulouse, France
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21
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Rastegar F, Gao JL, Shenaq D, Luo Q, Shi Q, Kim SH, Jiang W, Wagner ER, Huang E, Gao Y, Shen J, Yang K, He BC, Chen L, Zuo GW, Luo J, Luo X, Bi Y, Liu X, Li M, Hu N, Wang L, Luther G, Luu HH, Haydon RC, He TC. Lysophosphatidic acid acyltransferase β (LPAATβ) promotes the tumor growth of human osteosarcoma. PLoS One 2010; 5:e14182. [PMID: 21152068 PMCID: PMC2995727 DOI: 10.1371/journal.pone.0014182] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2010] [Accepted: 11/10/2010] [Indexed: 12/21/2022] Open
Abstract
Background Osteosarcoma is the most common primary malignancy of bone with poorly characterized molecular pathways important in its pathogenesis. Increasing evidence indicates that elevated lipid biosynthesis is a characteristic feature of cancer. We sought to investigate the role of lysophosphatidic acid acyltransferase β (LPAATβ, aka, AGPAT2) in regulating the proliferation and growth of human osteosarcoma cells. LPAATβ can generate phosphatidic acid, which plays a key role in lipid biosynthesis as well as in cell proliferation and survival. Although elevated expression of LPAATβ has been reported in several types of human tumors, the role of LPAATβ in osteosarcoma progression has yet to be elucidated. Methodology/Principal Findings Endogenous expression of LPAATβ in osteosarcoma cell lines is analyzed by using semi-quantitative PCR and immunohistochemical staining. Adenovirus-mediated overexpression of LPAATβ and silencing LPAATβ expression is employed to determine the effect of LPAATβ on osteosarcoma cell proliferation and migration in vitro and osteosarcoma tumor growth in vivo. We have found that expression of LPAATβ is readily detected in 8 of the 10 analyzed human osteosarcoma lines. Exogenous expression of LPAATβ promotes osteosarcoma cell proliferation and migration, while silencing LPAATβ expression inhibits these cellular characteristics. We further demonstrate that exogenous expression of LPAATβ effectively promotes tumor growth, while knockdown of LPAATβ expression inhibits tumor growth in an orthotopic xenograft model of human osteosarcoma. Conclusions/Significance Our results strongly suggest that LPAATβ expression may be associated with the aggressive phenotypes of human osteosarcoma and that LPAATβ may play an important role in regulating osteosarcoma cell proliferation and tumor growth. Thus, targeting LPAATβ may be exploited as a novel therapeutic strategy for the clinical management of osteosarcoma. This is especially attractive given the availability of selective pharmacological inhibitors.
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Affiliation(s)
- Farbod Rastegar
- Molecular Oncology Laboratory, Department of Surgery, The University of Chicago Medical Center, Chicago, Illinois, United States of America
| | - Jian-Li Gao
- Molecular Oncology Laboratory, Department of Surgery, The University of Chicago Medical Center, Chicago, Illinois, United States of America
- School of Pharmacy, Zhejiang University, Hangzhou, China
| | - Deana Shenaq
- Molecular Oncology Laboratory, Department of Surgery, The University of Chicago Medical Center, Chicago, Illinois, United States of America
| | - Qing Luo
- Molecular Oncology Laboratory, Department of Surgery, The University of Chicago Medical Center, Chicago, Illinois, United States of America
- Stem Cell Biology and Therapy Laboratory, The Children's Hospital of Chongqing Medical University, Chongqing, China
| | - Qiong Shi
- Molecular Oncology Laboratory, Department of Surgery, The University of Chicago Medical Center, Chicago, Illinois, United States of America
- Key Laboratory of Diagnostic Medicine designated by Chinese Ministry of Education, and Affiliated Hospitals of Chongqing Medical University, Chongqing, China
| | - Stephanie H. Kim
- Molecular Oncology Laboratory, Department of Surgery, The University of Chicago Medical Center, Chicago, Illinois, United States of America
| | - Wei Jiang
- Molecular Oncology Laboratory, Department of Surgery, The University of Chicago Medical Center, Chicago, Illinois, United States of America
| | - Eric R. Wagner
- Molecular Oncology Laboratory, Department of Surgery, The University of Chicago Medical Center, Chicago, Illinois, United States of America
| | - Enyi Huang
- Molecular Oncology Laboratory, Department of Surgery, The University of Chicago Medical Center, Chicago, Illinois, United States of America
- School of Bioengineering, Chongqing University, Chongqing, China
| | - Yanhong Gao
- Molecular Oncology Laboratory, Department of Surgery, The University of Chicago Medical Center, Chicago, Illinois, United States of America
- Department of Geriatrics, Xinhua Hospital of Shanghai Jiatong University, Shanghai, China
| | - Jikun Shen
- Molecular Oncology Laboratory, Department of Surgery, The University of Chicago Medical Center, Chicago, Illinois, United States of America
| | - Ke Yang
- Molecular Oncology Laboratory, Department of Surgery, The University of Chicago Medical Center, Chicago, Illinois, United States of America
- Department of Cell Biology, Third Military Medical University, Chongqing, China
| | - Bai-Cheng He
- Molecular Oncology Laboratory, Department of Surgery, The University of Chicago Medical Center, Chicago, Illinois, United States of America
- Key Laboratory of Diagnostic Medicine designated by Chinese Ministry of Education, and Affiliated Hospitals of Chongqing Medical University, Chongqing, China
| | - Liang Chen
- Molecular Oncology Laboratory, Department of Surgery, The University of Chicago Medical Center, Chicago, Illinois, United States of America
- Key Laboratory of Diagnostic Medicine designated by Chinese Ministry of Education, and Affiliated Hospitals of Chongqing Medical University, Chongqing, China
| | - Guo-Wei Zuo
- Molecular Oncology Laboratory, Department of Surgery, The University of Chicago Medical Center, Chicago, Illinois, United States of America
- Key Laboratory of Diagnostic Medicine designated by Chinese Ministry of Education, and Affiliated Hospitals of Chongqing Medical University, Chongqing, China
| | - Jinyong Luo
- Molecular Oncology Laboratory, Department of Surgery, The University of Chicago Medical Center, Chicago, Illinois, United States of America
- Key Laboratory of Diagnostic Medicine designated by Chinese Ministry of Education, and Affiliated Hospitals of Chongqing Medical University, Chongqing, China
| | - Xiaoji Luo
- Molecular Oncology Laboratory, Department of Surgery, The University of Chicago Medical Center, Chicago, Illinois, United States of America
- Key Laboratory of Diagnostic Medicine designated by Chinese Ministry of Education, and Affiliated Hospitals of Chongqing Medical University, Chongqing, China
| | - Yang Bi
- Molecular Oncology Laboratory, Department of Surgery, The University of Chicago Medical Center, Chicago, Illinois, United States of America
- Stem Cell Biology and Therapy Laboratory, The Children's Hospital of Chongqing Medical University, Chongqing, China
| | - Xing Liu
- Molecular Oncology Laboratory, Department of Surgery, The University of Chicago Medical Center, Chicago, Illinois, United States of America
- Stem Cell Biology and Therapy Laboratory, The Children's Hospital of Chongqing Medical University, Chongqing, China
| | - Mi Li
- Molecular Oncology Laboratory, Department of Surgery, The University of Chicago Medical Center, Chicago, Illinois, United States of America
- Stem Cell Biology and Therapy Laboratory, The Children's Hospital of Chongqing Medical University, Chongqing, China
| | - Ning Hu
- Molecular Oncology Laboratory, Department of Surgery, The University of Chicago Medical Center, Chicago, Illinois, United States of America
- Key Laboratory of Diagnostic Medicine designated by Chinese Ministry of Education, and Affiliated Hospitals of Chongqing Medical University, Chongqing, China
| | - Linyuan Wang
- Molecular Oncology Laboratory, Department of Surgery, The University of Chicago Medical Center, Chicago, Illinois, United States of America
| | - Gaurav Luther
- Molecular Oncology Laboratory, Department of Surgery, The University of Chicago Medical Center, Chicago, Illinois, United States of America
| | - Hue H. Luu
- Molecular Oncology Laboratory, Department of Surgery, The University of Chicago Medical Center, Chicago, Illinois, United States of America
| | - Rex C. Haydon
- Molecular Oncology Laboratory, Department of Surgery, The University of Chicago Medical Center, Chicago, Illinois, United States of America
| | - Tong-Chuan He
- Molecular Oncology Laboratory, Department of Surgery, The University of Chicago Medical Center, Chicago, Illinois, United States of America
- School of Pharmacy, Zhejiang University, Hangzhou, China
- Stem Cell Biology and Therapy Laboratory, The Children's Hospital of Chongqing Medical University, Chongqing, China
- * E-mail:
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22
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Takeuchi K, Reue K. Biochemistry, physiology, and genetics of GPAT, AGPAT, and lipin enzymes in triglyceride synthesis. Am J Physiol Endocrinol Metab 2009; 296:E1195-209. [PMID: 19336658 PMCID: PMC2692402 DOI: 10.1152/ajpendo.90958.2008] [Citation(s) in RCA: 306] [Impact Index Per Article: 20.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/29/2008] [Accepted: 03/30/2009] [Indexed: 01/19/2023]
Abstract
Triacylglycerol (TAG) synthesis and storage in tissues such as adipose tissue and liver have important roles in metabolic homeostasis. The molecular identification of genes encoding enzymes that catalyze steps in TAG biosynthesis from glycerol 3-phosphate has revealed an unexpected number of protein isoforms of the glycerol phosphate acyltransferase (GPAT), acylglycerolphosphate acyltransferase (AGPAT), and lipin (phosphatidate phosphatase) families that appear to catalyze similar biochemical reactions. However, on the basis of available data for a few members in which genetic deficiencies in mouse and/or human have been studied, we postulate that each GPAT, AGPAT, and lipin family member likely has a specialized role that may be uncovered through careful biochemical and physiological analyses.
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Affiliation(s)
- Kazuharu Takeuchi
- Dept. of Human Genetics, Gonda 6506A, David Geffen School of Medicine at UCLA, 695 Charles E. Young Drive South, Los Angeles, CA 90095, USA
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23
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Abstract
Maintenance of body temperature is achieved partly by modulating lipolysis by a network of complex regulatory mechanisms. Lipolysis is an integral part of the glycerolipid/free fatty acid (GL/FFA) cycle, which is the focus of this review, and we discuss the significance of this pathway in the regulation of many physiological processes besides thermogenesis. GL/FFA cycle is referred to as a "futile" cycle because it involves continuous formation and hydrolysis of GL with the release of heat, at the expense of ATP. However, we present evidence underscoring the "vital" cellular signaling roles of the GL/FFA cycle for many biological processes. Probably because of its importance in many cellular functions, GL/FFA cycling is under stringent control and is organized as several composite short substrate/product cycles where forward and backward reactions are catalyzed by separate enzymes. We believe that the renaissance of the GL/FFA cycle is timely, considering the emerging view that many of the neutral lipids are in fact key signaling molecules whose production is closely linked to GL/FFA cycling processes. The evidence supporting the view that alterations in GL/FFA cycling are involved in the pathogenesis of "fatal" conditions such as obesity, type 2 diabetes, and cancer is discussed. We also review the different enzymatic and transport steps that encompass the GL/FFA cycle leading to the generation of several metabolic signals possibly implicated in the regulation of biological processes ranging from energy homeostasis, insulin secretion and appetite control to aging and longevity. Finally, we present a perspective of the possible therapeutic implications of targeting this cycling.
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Affiliation(s)
- Marc Prentki
- Departments of Nutrition and Biochemistry, University of Montreal, Montreal Diabetes Research Center, CR-CHUM, Montreal, Quebec, Canada H1W 4A4.
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Johnson AJ, Wagner AJ, Cheney CM, Smith LL, Lucas DM, Guster SK, Grever MR, Lin TS, Byrd JC. Rituximab and 17-allylamino-17-demethoxygeldanamycin induce synergistic apoptosis in B-cell chronic lymphocytic leukaemia. Br J Haematol 2007; 139:837-44. [DOI: 10.1111/j.1365-2141.2007.06878.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Yamashita A, Nakanishi H, Suzuki H, Kamata R, Tanaka K, Waku K, Sugiura T. Topology of acyltransferase motifs and substrate specificity and accessibility in 1-acyl-sn-glycero-3-phosphate acyltransferase 1. Biochim Biophys Acta Mol Cell Biol Lipids 2007; 1771:1202-15. [PMID: 17707131 DOI: 10.1016/j.bbalip.2007.07.002] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2007] [Revised: 06/22/2007] [Accepted: 07/04/2007] [Indexed: 11/20/2022]
Abstract
1-acyl-sn-glycero-3-phosphate (AGP) acyltransferases (AGPAT) are involved in de novo biosynthesis of glycerolipids, such as phospholipids and triacylglycerol. Alignment of amino acid sequences from AGPAT, sn-glycerol-3-phosphate acyltransferase, and dihydroxyacetonephosphate acyltransferase reveals four regions with strong homology (acyltransferase motifs I-IV). The invariant amino acids within these regions may be part of a catalytically important site in this group of acyl-CoA acyltransferases. However, in human AGPAT1 a transmembrane domain is predicted to separate motif I on the cytosolic side from motifs II-III on the lumenal side, with motif IV near surface of the membrane. The topology of motifs I and III was confirmed by experiments with recombinant AGPAT1 containing potential glycosylation site near the motifs. This topology conflicts with the expectation that catalytically important sites are near one another, raising questions of whether the acyltransferase motifs really are important for AGPAT catalysis, and how substrates access motifs II-III on the lumenal side of the endoplasmic reticulum membrane. Using human AGPAT1 as a model, we have examined the catalytic roles of highly conserved residues in the four acyltransferase motifs by site-directed mutagenesis. Modifications of the sidechain structures of His104, Asp109, Phe146, Arg149, Glu178, Gly179, Thr180, Arg181 and Ile208 all affected AGPAT1 activity, indicating that the acyltransferase motifs indeed are important for AGPAT catalysis. In addition, we examined substrate accessibility to the catalytic domain of human AGPAT1 using a competition assay. Lysophosphatidic acid (LPA) with fatty acid chains shorter than 10 carbons did not access the catalytic domain, suggesting that LPA hydrophobicity is important. In contrast, short chain acyl-CoAs did access the catalytic domain but did not serve as the second substrate. These results suggest that motifs II and III are involved in LPA binding and motifs I and IV are involved in acyl-CoA binding.
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Affiliation(s)
- Atsushi Yamashita
- Faculty of Pharmaceutical Sciences, Teikyo University, Sagamiko, Sagamihara, Kanagawa 229-0195, Japan.
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26
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Kaleem Z. Flow cytometric analysis of lymphomas: current status and usefulness. Arch Pathol Lab Med 2006; 130:1850-8. [PMID: 17149963 DOI: 10.5858/2006-130-1850-fcaolc] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/26/2006] [Indexed: 11/06/2022]
Abstract
CONTEXT Immunophenotyping has become a routine practice in the diagnosis and classification of most cases of non-Hodgkin lymphoma, and flow cytometry is often the method of choice in many laboratories. The role that flow cytometry plays, however, extends beyond just diagnosis and classification. OBJECTIVE To review and evaluate the current roles of flow cytometry in non-Hodgkin lymphoma, to compare it with immunohistochemistry, and to discuss its potential future applications in the molecular diagnostic era. DATA SOURCES The information contained herein is derived from peer-reviewed articles on the subject published in the English-language medical literature during the years 1980 to 2005 that were identified using PubMed (http://www.ncbi.nlm.nih.gov/entrez/query.fcgi, 1980-2005) search, various books and other sources on flow cytometry, and the author's personal experience of more than 10 years with flow cytometric analysis of lymphomas and leukemia using Becton-Dickinson (San Jose, Calif) and Beckman-Coulter (Miami, Fla) flow cytometers. STUDY SELECTION Studies were selected based on adequate material and methods, statistically significant results, and adequate clinical follow-up. DATA EXTRACTION The data from various sources were compared when the methods used were the same or similar and appropriate controls were included. Most of the studies employed 2-color, 3-color, or 4-color flow cytometers with antibodies from Becton-Dickinson, Beckman-Coulter, or DakoCytomation (Carpinteria, Calif). Results were evaluated from studies utilizing the same or similar techniques and flow cytometers. Only objective data analyses from relevant and useful publications were included for reporting and discussion. DATA SYNTHESIS Flow cytometry serves a variety of roles in the field of lymphoma/leukemia including rapid diagnosis, proper classification, staging, minimal residual disease detection, central nervous system lymphoma detection, evaluation of prognostic markers, detection of target molecules for therapies, ploidy analysis of lymphoma cell DNA, and evaluation of multidrug-resistance markers. It offers many advantages in comparison to immunohistochemistry for the same roles and provides uses that are either not possible or not preferable by immunohistochemistry such as multiparameter evaluation of single cells and detection of clonality in T cells. CONCLUSIONS By virtue of its ability to evaluate not only surface but also cytoplasmic and nuclear antigens, flow cytometry continues to enjoy widespread use in various capacities in lymphoma evaluation and treatment. Additional roles for flow cytometry are likely to be invented in the future and should provide distinctive uses in the molecular era.
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Affiliation(s)
- Zahid Kaleem
- Pathology & Laboratory Research Medical Center, Kansas City, MO, USA.
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Teeling JL, Mackus WJM, Wiegman LJJM, van den Brakel JHN, Beers SA, French RR, van Meerten T, Ebeling S, Vink T, Slootstra JW, Parren PWHI, Glennie MJ, van de Winkel JGJ. The biological activity of human CD20 monoclonal antibodies is linked to unique epitopes on CD20. THE JOURNAL OF IMMUNOLOGY 2006; 177:362-71. [PMID: 16785532 DOI: 10.4049/jimmunol.177.1.362] [Citation(s) in RCA: 453] [Impact Index Per Article: 25.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
We have previously defined a panel of fully human CD20 mAb. Most of these were unexpectedly efficient in their ability to recruit C1q to the surface of CD20-positive cells and mediate tumor lysis via activation of the classical pathway of complement. This complement-dependent cytotoxicity (CDC) potency appeared to relate to the unusually slow off-rate of these human Abs. However, we now present epitope-mapping data, which indicates that all human mAb bind a novel region of CD20 that may influence CDC potency. Epitope mapping, using both mutagenesis studies and overlapping 15-mer peptides of the extracellular loops of CD20, defined the amino acids required for binding by an extensive panel of mouse and human mAb. Binding by rituximab and mouse CD20 mAb, had an absolute requirement for alanine and proline at positions 170 and 172, respectively, within the large extracellular loop of CD20. Surprisingly, however, all of the human CD20 mAb recognize a completely novel epitope located N-terminally of this motif, also including the small extracellular loop of CD20. Thus, although off-rate may influence biological activity of mAb, another critical factor for determining CDC potency by CD20 mAb appears to be the region of the target molecule they recognize. We conclude that recognition of the novel epitope cooperates with slow off-rate in determining the activity of CD20 Ab in activation of complement and induction of tumor cell lysis.
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MESH Headings
- Amino Acid Sequence
- Animals
- Antibodies, Monoclonal/genetics
- Antibodies, Monoclonal/metabolism
- Antigens, CD20/genetics
- Antigens, CD20/immunology
- Antigens, CD20/metabolism
- Antigens, Neoplasm/immunology
- Antigens, Neoplasm/metabolism
- Antineoplastic Agents/metabolism
- Binding Sites, Antibody/genetics
- Cell Line
- Cell Line, Tumor
- Complement Pathway, Classical/genetics
- Complement Pathway, Classical/immunology
- Cytotoxicity, Immunologic/genetics
- Epitope Mapping
- Epitopes/genetics
- Epitopes/immunology
- Epitopes/metabolism
- Humans
- Immunoglobulin G/metabolism
- Lymphoma/immunology
- Lymphoma/pathology
- Lymphoma/therapy
- Mice
- Mice, Transgenic
- Molecular Sequence Data
- Mutagenesis, Site-Directed
- Peptide Fragments/chemical synthesis
- Peptide Fragments/immunology
- Peptide Fragments/metabolism
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Douvas MG, Hogan KN, Ji Y, Hollenback D, Bonham L, Singer JW, Mitchell BS. Effect of lysophosphatidic acid acyltransferase-β inhibition in acute leukemia. Leuk Res 2006; 30:1027-36. [PMID: 16488473 DOI: 10.1016/j.leukres.2005.11.018] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2005] [Revised: 11/22/2005] [Accepted: 11/23/2005] [Indexed: 11/17/2022]
Abstract
Phosphatidic acid (PA) is an important component of mammalian target of rapamycin (mTOR) signaling and in the recruitment of Raf to the cell membrane. PA can be produced by several mechanisms, including by a series of lysophosphatidic acid acyl transferases (LPAATs). LPAAT-beta is an isoform that is overexpressed in some human cancers and its inhibition has been investigated as a potential targeted cancer therapy. We report that LPAAT-protein and enzyme activity in acute leukemia cell lines and blasts from patient samples are equivalent to levels in normal mononuclear cells. Treatment with the LPAAT-beta inhibitor CT-32228 (Cell Therapeutics, Seattle, WA) uniformly induces apoptosis in multiple leukemia cell lines. In patient samples, however, apoptosis was variably induced by CT-32228 and appeared to be related to the degree of cellular proliferation. The growth inhibitory effect of CT-32228 on normal hematopoietic progenitors was more pronounced in cells induced to proliferate by growth factors. These data suggest that CT-32228 may have potential in the treatment of acute leukemias, but that efficacy is more directly related to the degree of cell proliferation rather than to the level of LPAAT-beta expression or activity.
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Affiliation(s)
- Michael G Douvas
- Department of Pediatrics, Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill School of Medicine, USA.
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