99 results on '"GOT2"'
Search Results
2. GLS and GOT2 as prognostic biomarkers associated with dendritic cell and immunotherapy response in breast cancer
- Author
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Ruifang Yang, Shuo Cheng, Jie Xiao, Yujie Pei, Zhonglin Zhu, Jifa Zhang, Jing Feng, and Jing Li
- Subjects
Breast cancer ,Dendritic cell ,Immune checkpoint ,GLS1 ,GOT2 ,Science (General) ,Q1-390 ,Social sciences (General) ,H1-99 - Abstract
Breast cancer is the females' most common cancer. Targeting the immune microenvironment is a new and promising treatment method for breast cancer. Nevertheless, only a small section of patients can profit by immunotherapy, and improving the ability to accurately predict the potential for immunotherapy response is still awaiting further exploration. In this study, we found that the key factors of glutamine metabolism, glutaminase 1 (GLS) and mitochondrial aspartate transaminase (GOT2), showed opposite expression patterns in breast cancer samples. Based on the expression level of GLS and GOT2, we divided the breast cancer samples into two clusters: Cluster 2 showed GLS expressed higher and GOT2 expressed lower, whereas Cluster 1 showed GOT2 expressed higher and GLS expressed lower. GSEA showed that the clusters were related to pathways of immunity. Further analysis showed that Cluster 2 was positively associated with immunity infiltration. Through WGCNA, we identified a module strongly correlated with glutamine metabolism and immunity and identified 11 dendritic cell-associated genes involved in dendritic cell development, maturation, activation and other functions. In addition, Cluster 2 also showed higher immune checkpoint gene expression, which suggest the Cluster 2 had even better response to immunotherapy. The validation dataset could also be clustered into two groups. Cluster 2 (GLS expressed higher and GOT2 expressed lower) of the validation dataset was also positively associated with dendritic cells and a better immunotherapy response. Thus, these data indicate that GLS and GOT2 are prognostic biomarkers which closely related to dendritic cells and better reacted to immunotherapy in breast cancer.
- Published
- 2024
- Full Text
- View/download PDF
3. A novel metabolism-related gene signature in patients with hepatocellular carcinoma.
- Author
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Bin Ru, Jiaqi Hu, Nannan Zhang, and Quan Wan
- Subjects
HEPATOCELLULAR carcinoma ,DISEASE risk factors ,CANCER cell proliferation ,CANCER prognosis ,CELL cycle - Abstract
Hepatocellular carcinoma (HCC) remains a global challenge as it is the sixth most common neoplasm worldwide and the third leading cause of cancer-related death. A key feature of HCC is abnormal metabolism, which promotes cancer cell proliferation, survival, invasion, and metastasis. However, the significance of metabolism-related genes (MRGs) in HCC remains to be elucidated. Here, we aim to establish a novel metabolism-related prognostic signature for the prediction of patient outcomes and to investigate the value of MRG expression in the prognostic prediction of HCC. In our research, a Metabolism-Related Risk Score (MRRS) model was constructed using 14 MRGs (DLAT, SEPHS1, ACADS, UCK2, GOT2, ADH4, LDHA, ME1, TXNRD1, B4GALT2, AK2, PTDSS2, CSAD, and AMD1). The Kaplan-Meier curve confirmed that the MRRS has a high accuracy in predicting the prognosis of HCC patients (p<0:001). According to theMRRSmodel, the area under the curve (AUC) values for predicting the prognosis of patients with hepatocellular carcinoma at 1, 3, and 5 years reached 0.829, 0.760, and 0.739, respectively. Functional analyses revealed that signaling pathways associated with the cell cycle were largely enriched by differential genes between high and low-risk groups. In addition, dendritic cells (DCs) (p < 0:001), CD4+ T cells (p < 0:01), CD8+ T cells (p < 0:001), B cells (p < 0:001), neutrophils (p < 0:001), macrophages (p<0:001) had a higher proportion of infiltrates in high-risk populations. Low GOT2 expression is associated with poor prognosis in patients with hepatocellular carcinoma. Knockdown of GOT2 significantly increased the migration capacity of the Huh7 and MHCC97H hepatocellular carcinoma lines. Our research reveals that GOT2 is negatively related to the survival of patients with hepatocellular carcinoma and GOT2 may contribute to tumor progression by inhibiting the ability of tumor cells to migrate. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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- View/download PDF
4. Surgical resection of lung cancer inhibits mRNA expression of GOT2 gene encoding kynurenine aminotransferase in leukocytes.
- Author
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Prystupa, Tomasz Karol, Sagan, Dariusz, Kocki, Janusz, Kocki, Tomasz, Szymanowski, Rafał, and Bogucki, Jacek
- Published
- 2023
- Full Text
- View/download PDF
5. Combining single-cell and transcriptomic analysis revealed the immunomodulatory effect of GOT2 on a glutamine-dependent manner in cutaneous melanoma.
- Author
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Lebin Song, Xiyi Wei, Xi Zhang, and Yan Lu
- Subjects
GLUTAMINE ,MELANOMA ,TRANSCRIPTOMES ,SKIN diseases ,GENETIC mutation ,BRAF genes ,CELL proliferation - Abstract
Background: Reprogramming in glutamine metabolism is a hallmark of cancers, while its role in cutaneous melanoma has not been studied at great length. Methods: Here, we constructed a glutamine metabolism-related prognostic signature in cutaneous melanoma with a variety of bioinformatics methods according to the glutamine metabolism regulatory molecules. Moreover, experimental verification was carried out for the key gene. Results: We have identified two subgroups of cutaneous melanoma patients, each with different prognoses, immune characteristics, and genetic mutations. GOT2 was the most concerned key gene among the model genes. We verified its role in promoting tumor cell proliferation by CCK-8 and clone formation assays. Conclusion: Our study cast new light on the prognosis of cutaneous melanoma, and the internal mechanism regulating glutamine metabolism of GOT2 may provide a new avenue for treating the cutaneous melanoma disease precisely. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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6. An asparagine metabolism-based classification reveals the metabolic and immune heterogeneity of hepatocellular carcinoma
- Author
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Jianguo Bai, Ruifeng Tang, Keyu Zhou, Jialei Chang, Hongyue Wang, Qixin Zhang, Jiahui Shi, and Chao Sun
- Subjects
Hepatocellular carcinoma ,Asparagine metabolism ,Tumor microenvironment ,DNA damage response ,GOT2 ,Internal medicine ,RC31-1245 ,Genetics ,QH426-470 - Abstract
Abstract Introduction and objectives hepatocellular carcinoma (HCC) is the major form of liver cancer with a poor prognosis. Amino acid metabolism has been found to alter in cancers and contributes to malignant progression. However, the asparagine metabolism status and relevant mechanism in HCC were barely understood. Methods By conducting consensus clustering and the least absolute shrinkage and selection operator regression of HCC samples from three cohorts, we classified the HCC patients into two subtypes based on asparagine metabolism level. The Gene Ontology, Kyoto Encyclopedia of Genes and Genomes analyses and Gene Set Enrichment Analysis of the differentially expressed genes between two subgroups were conducted. Immune cell infiltration was evaluated using CIBERSORT algorithm. The prognostic values of genes were analyzed by univariate and multivariate cox regression, ROC curve and Kaplan–Meier survival estimate analyses. Cell types of sing-cell RNA sequencing (scRNA-seq) data were clustered utilizing UMAP method. Results HCC patients with higher asparagine metabolism level have worse prognoses. Moreover, we found the distinct energy metabolism patterns, DNA damage response (DDR) pathway activating levels, drug sensitivities to DDR inhibitors, immune cell compositions in the tumor microenvironment and responses to immune therapy between two subgroups. Further, we identified a potential target gene, glutamic-oxaloacetic transaminase 2 (GOT2). GOT2 downregulation was associated with worse HCC prognosis and increased infiltration of T regulatory cells (Tregs). ScRNA-seq revealed the GOT2 downregulation in cancer stem cells compared with HCC cells. Conclusions Taken together, HCC subtype which is more reliant on asparagine and glutamine metabolism has a worse prognosis, and a core gene of asparagine metabolism GOT2 is a potential prognostic marker and therapeutic target of HCC. Our study promotes the precision therapy of HCC and may improve patient outcomes.
- Published
- 2022
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- View/download PDF
7. Expression of GOT2 Is Epigenetically Regulated by DNA Methylation and Correlates with Immune Infiltrates in Clear-Cell Renal Cell Carcinoma
- Author
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Wallax Augusto Silva Ferreira and Edivaldo Herculano Correa de Oliveira
- Subjects
KIRC ,GOT2 ,multi-omics ,epigenetics ,immune cell infiltration ,Biology (General) ,QH301-705.5 - Abstract
Clear cell renal cell carcinoma (KIRC) is the most common and highly malignant pathological type of kidney cancer, characterized by a profound metabolism dysregulation. As part of aspartate biosynthesis, mitochondrial GOT2 (glutamic-oxaloacetic transaminase 2) is essential for regulating cellular energy production and biosynthesis, linking multiple pathways. Nevertheless, the expression profile and prognostic significance of GOT2 in KIRC remain unclear. This study comprehensively analyzed the transcriptional levels, epigenetic regulation, correlation with immune infiltration, and prognosis of GOT2 in KIRC using rigorous bioinformatics analysis. We discovered that the expression levels of both mRNA and protein of GOT2 were remarkably decreased in KIRC tissues in comparison with normal tissues and were also significantly related to the clinical features and prognosis of KIRC. Remarkably, low GOT2 expression was positively associated with poorer overall survival (OS) and disease-free survival (DFS). Further analysis revealed that GOT2 downregulation is driven by DNA methylation in the promoter-related CpG islands. Finally, we also shed light on the influence of GOT2 expression in immune cell infiltration, suggesting that GOT2 may be a potential prognostic marker and therapeutic target for KIRC patients.
- Published
- 2022
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8. STXBP3 and GOT2 predict immunological activity in acute allograft rejection.
- Author
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Qinfan Yao, Cuili Wang, Yucheng Wang, Wenyu Xiang, Yin Chen, Qin Zhou, Jianghua Chen, Hong Jiang, and Dajin Chen
- Subjects
GRAFT rejection ,HOMOGRAFTS ,ASPARTATE aminotransferase ,KIDNEY transplantation ,ENZYME-linked immunosorbent assay ,RECEIVER operating characteristic curves - Abstract
Background: Acute allograft rejection (AR) following renal transplantation contributes to chronic rejection and allograft dysfunction. The current diagnosis of AR remains dependent on renal allograft biopsy which cannot immediately detect renal allograft injury in the presence of AR. In this study, sensitive biomarkers for AR diagnosis were investigated and developed to protect renal function. Methods: We analyzed pre- and postoperative data from five databases combined with our own data to identify the key differently expressed genes (DEGs). Furthermore, we performed a bioinformatics analysis to determine the immune characteristics of DEGs. The expression of key DEGs was further confirmed using the real-time quantitative PCR (RT-qPCR), enzyme-linked immunosorbent assay (ELISA), and immunohistochemical (IHC) staining in patients with AR. ROC curves analysis was used to estimate the performance of key DEGs in the early diagnosis of AR. Results: We identified glutamic-oxaloacetic transaminase 2 (GOT2) and syntaxin binding protein 3 (STXBP3) as key DEGs. The higher expression of STXBP3 and GOT2 in patients with AR was confirmed using RT-qPCR, ELISA, and IHC staining. ROC curve analysis also showed favorable values of STXBP3 and GOT2 for the diagnosis of early stage AR. Conclusions: STXBP3 and GOT2 could reflect the immunological status of patients with AR and have strong potential for the diagnosis of early-stage AR. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
9. An asparagine metabolism-based classification reveals the metabolic and immune heterogeneity of hepatocellular carcinoma.
- Author
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Bai, Jianguo, Tang, Ruifeng, Zhou, Keyu, Chang, Jialei, Wang, Hongyue, Zhang, Qixin, Shi, Jiahui, and Sun, Chao
- Subjects
- *
DNA repair , *HEPATOCELLULAR carcinoma , *ASPARAGINE , *REGULATORY T cells , *ASPARTATE aminotransferase - Abstract
Introduction and objectives: hepatocellular carcinoma (HCC) is the major form of liver cancer with a poor prognosis. Amino acid metabolism has been found to alter in cancers and contributes to malignant progression. However, the asparagine metabolism status and relevant mechanism in HCC were barely understood. Methods: By conducting consensus clustering and the least absolute shrinkage and selection operator regression of HCC samples from three cohorts, we classified the HCC patients into two subtypes based on asparagine metabolism level. The Gene Ontology, Kyoto Encyclopedia of Genes and Genomes analyses and Gene Set Enrichment Analysis of the differentially expressed genes between two subgroups were conducted. Immune cell infiltration was evaluated using CIBERSORT algorithm. The prognostic values of genes were analyzed by univariate and multivariate cox regression, ROC curve and Kaplan–Meier survival estimate analyses. Cell types of sing-cell RNA sequencing (scRNA-seq) data were clustered utilizing UMAP method. Results: HCC patients with higher asparagine metabolism level have worse prognoses. Moreover, we found the distinct energy metabolism patterns, DNA damage response (DDR) pathway activating levels, drug sensitivities to DDR inhibitors, immune cell compositions in the tumor microenvironment and responses to immune therapy between two subgroups. Further, we identified a potential target gene, glutamic-oxaloacetic transaminase 2 (GOT2). GOT2 downregulation was associated with worse HCC prognosis and increased infiltration of T regulatory cells (Tregs). ScRNA-seq revealed the GOT2 downregulation in cancer stem cells compared with HCC cells. Conclusions: Taken together, HCC subtype which is more reliant on asparagine and glutamine metabolism has a worse prognosis, and a core gene of asparagine metabolism GOT2 is a potential prognostic marker and therapeutic target of HCC. Our study promotes the precision therapy of HCC and may improve patient outcomes. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
10. Plasma proteomics implicate glutamic oxaloacetic transaminases as potential markers for acute myocardial infarction.
- Author
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Wei, QingJiang, Li, Kela, Su, Liye, Cen, Tuan, Sooranna, Suren R., Pan, Xinshou, Huang, Zhaohe, and Liu, Yan
- Subjects
- *
ASPARTATE aminotransferase , *MYOCARDIAL infarction , *METHIONINE metabolism , *PROTEIN domains , *HEART failure patients - Abstract
To provide a novel perspective on the pathogenesis of acute myocardial infarction (AMI) patients with respect to glutamic oxaloacetic transaminase (GOT). The plasma proteome of 20 patients with AMI were matched for age and sex and compared with 10 healthy individuals. We analyzed the mass spectrum data and compared the signal intensity of the corresponding peptides which related to their corresponding proteins. A sample-specific protein database was constructed and a quality control analysis was conducted to screen out the key regulatory proteins under specific experimental conditions. The data from 37 new AMI patients and 13 healthy adults were subjected to parallel reaction monitoring (PRM) to verify the target proteins found. Finally, the survival status of the key genes (> 1.5-fold) in the PPI were analyzed. 2589 and 2162 proteins were identified and quantified, respectively, and 143 differentially expressed proteins (DEPs) (≥1.5-fold) were found between the AMI and control groups. Of these 90 and 53 were significantly up-regulated and down-regulated, respectively. Gene ontology, KEGG enrichment, protein domain and cluster analysis as well as PPI networks of the DEPs revealed a central role of acute inflammatory response processes in patients with AMI. A cluster of proteins were found to be related to cysteine, methionine, arginine, proline, phenylalanine and propanoate metabolism as well as the cAMP signaling pathway. PPI network analysis showed CHI3L1, COPB2, GOT2, MB, CYCS, GOT1, CKM, SAA1 and PRKCD and RPS3 were in key positions, but only MB, CKM, GOT1, PRKCD, CYCS and GOT2 were found in a cluster. PRM verified the high levels of MB, CKM, GOT1 and GOT2 in 37 AMI patients but there was no statistical difference in the survival status for patients with either high or low expression levels of these proteins. Our findings showed that acute inflammatory response processes play a central role in patients with AMI. Cysteine and methionine metabolism was also activated, in which GOT1 and GOT2 were key proteins. These pathways might be potential targets for diagnosis and novel therapies to improve the poor outcomes observed in patients with heart failure. [Display omitted] • The plasma proteome of AMI patients and controls expressed different proteins. • PPI network analysis showed GOT1, GOT2, CKM, MB, PRKCD and CYCS in a cluster. • Parallel reaction monitoring verified GOT1, GOT2, CKM and MB as target proteins. • The related pathways provide potential targets for diagnosis and therapies for AMI. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
11. SIRT3‐dependent GOT2 acetylation status affects the malate–aspartate NADH shuttle activity and pancreatic tumor growth
- Author
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Yang, Hui, Zhou, Lisha, Shi, Qian, Zhao, Yuzheng, Lin, Huaipeng, Zhang, Mengli, Zhao, Shimin, Yang, Yi, Ling, Zhi-Qiang, Guan, Kun-Liang, Xiong, Yue, and Ye, Dan
- Subjects
Rare Diseases ,Cancer ,Acetylation ,Animals ,Aspartate Aminotransferase ,Mitochondrial ,Aspartic Acid ,Biological Transport ,Carcinoma ,Pancreatic Ductal ,Cell Proliferation ,Cells ,Cultured ,HEK293 Cells ,Humans ,Malates ,Male ,Mice ,Mice ,Inbred C57BL ,Mice ,Nude ,NAD ,Oxidation-Reduction ,Pancreatic Neoplasms ,Protein Processing ,Post-Translational ,Sirtuin 3 ,acetylation ,GOT2 ,malate-aspartate NADH shuttle ,pancreatic cancer ,malate–aspartate NADH shuttle ,Biological Sciences ,Information and Computing Sciences ,Medical and Health Sciences ,Developmental Biology - Abstract
The malate-aspartate shuttle is indispensable for the net transfer of cytosolic NADH into mitochondria to maintain a high rate of glycolysis and to support rapid tumor cell growth. The malate-aspartate shuttle is operated by two pairs of enzymes that localize to the mitochondria and cytoplasm, glutamate oxaloacetate transaminases (GOT), and malate dehydrogenases (MDH). Here, we show that mitochondrial GOT2 is acetylated and that deacetylation depends on mitochondrial SIRT3. We have identified that acetylation occurs at three lysine residues, K159, K185, and K404 (3K), and enhances the association between GOT2 and MDH2. The GOT2 acetylation at these three residues promotes the net transfer of cytosolic NADH into mitochondria and changes the mitochondrial NADH/NAD(+) redox state to support ATP production. Additionally, GOT2 3K acetylation stimulates NADPH production to suppress ROS and to protect cells from oxidative damage. Moreover, GOT2 3K acetylation promotes pancreatic cell proliferation and tumor growth in vivo. Finally, we show that GOT2 K159 acetylation is increased in human pancreatic tumors, which correlates with reduced SIRT3 expression. Our study uncovers a previously unknown mechanism by which GOT2 acetylation stimulates the malate-aspartate NADH shuttle activity and oxidative protection.
- Published
- 2015
12. Inborn disorders of the malate aspartate shuttle.
- Author
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Broeks, Melissa H., Karnebeek, Clara D. M., Wanders, Ronald J. A., Jans, Judith J. M., and Verhoeven‐Duif, Nanda M.
- Abstract
Over the last few years, various inborn disorders have been reported in the malate aspartate shuttle (MAS). The MAS consists of four metabolic enzymes and two transporters, one of them having two isoforms that are expressed in different tissues. Together they form a biochemical pathway that shuttles electrons from the cytosol into mitochondria, as the inner mitochondrial membrane is impermeable to the electron carrier NADH. By shuttling NADH across the mitochondrial membrane in the form of a reduced metabolite (malate), the MAS plays an important role in mitochondrial respiration. In addition, the MAS maintains the cytosolic NAD+/NADH redox balance, by using redox reactions for the transfer of electrons. This explains why the MAS is also important in sustaining cytosolic redox‐dependent metabolic pathways, such as glycolysis and serine biosynthesis. The current review provides insights into the clinical and biochemical characteristics of MAS deficiencies. To date, five out of seven potential MAS deficiencies have been reported. Most of them present with a clinical phenotype of infantile epileptic encephalopathy. Although not specific, biochemical characteristics include high lactate, high glycerol 3‐phosphate, a disturbed redox balance, TCA abnormalities, high ammonia, and low serine, which may be helpful in reaching a diagnosis in patients with an infantile epileptic encephalopathy. Current implications for treatment include a ketogenic diet, as well as serine and vitamin B6 supplementation. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
13. Preventing BRCA1/ZBRK1 repressor complex binding to the GOT2 promoter results in accelerated aspartate biosynthesis and promotion of cell proliferation
- Author
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Ruoxi Hong, Weimin Zhang, Xi Xia, Kai Zhang, Yan Wang, Mengjiao Wu, Jiawen Fan, Jinting Li, Wen Xia, Fei Xu, Jie Chen, Shusen Wang, and Qimin Zhan
- Subjects
aspartate ,BRCA1 ,breast cancer ,co‐repressor ,GOT2 ,ZBRK1 ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Breast cancer susceptibility gene 1 (BRCA1) has been implicated in modulating metabolism via transcriptional regulation. However, direct metabolic targets of BRCA1 and the underlying regulatory mechanisms are still unknown. Here, we identified several metabolic genes, including the gene which encodes glutamate‐oxaloacetate transaminase 2 (GOT2), a key enzyme for aspartate biosynthesis, which are repressed by BRCA1. We report that BRCA1 forms a co‐repressor complex with ZBRK1 that coordinately represses GOT2 expression via a ZBRK1 recognition element in the promoter of GOT2. Impairment of this complex results in upregulation of GOT2, which in turn increases aspartate and alpha ketoglutarate production, leading to rapid cell proliferation of breast cancer cells. Importantly, we found that GOT2 can serve as an independent prognostic factor for overall survival and disease‐free survival of patients with breast cancer, especially triple‐negative breast cancer. Interestingly, we also demonstrated that GOT2 overexpression sensitized breast cancer cells to methotrexate, suggesting a promising precision therapeutic strategy for breast cancer treatment. In summary, our findings reveal that BRCA1 modulates aspartate biosynthesis through transcriptional repression of GOT2, and provides a biological basis for treatment choices in breast cancer.
- Published
- 2019
- Full Text
- View/download PDF
14. GLS and GOT2 as prognostic biomarkers associated with dendritic cell and immunotherapy response in breast cancer.
- Author
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Yang R, Cheng S, Xiao J, Pei Y, Zhu Z, Zhang J, Feng J, and Li J
- Abstract
Breast cancer is the females' most common cancer. Targeting the immune microenvironment is a new and promising treatment method for breast cancer. Nevertheless, only a small section of patients can profit by immunotherapy, and improving the ability to accurately predict the potential for immunotherapy response is still awaiting further exploration. In this study, we found that the key factors of glutamine metabolism, glutaminase 1 (GLS) and mitochondrial aspartate transaminase (GOT2), showed opposite expression patterns in breast cancer samples. Based on the expression level of GLS and GOT2, we divided the breast cancer samples into two clusters: Cluster 2 showed GLS expressed higher and GOT2 expressed lower, whereas Cluster 1 showed GOT2 expressed higher and GLS expressed lower. GSEA showed that the clusters were related to pathways of immunity. Further analysis showed that Cluster 2 was positively associated with immunity infiltration. Through WGCNA, we identified a module strongly correlated with glutamine metabolism and immunity and identified 11 dendritic cell-associated genes involved in dendritic cell development, maturation, activation and other functions. In addition, Cluster 2 also showed higher immune checkpoint gene expression, which suggest the Cluster 2 had even better response to immunotherapy. The validation dataset could also be clustered into two groups. Cluster 2 (GLS expressed higher and GOT2 expressed lower) of the validation dataset was also positively associated with dendritic cells and a better immunotherapy response. Thus, these data indicate that GLS and GOT2 are prognostic biomarkers which closely related to dendritic cells and better reacted to immunotherapy in breast cancer., Competing Interests: The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Jing Feng reports financial support was provided by 10.13039/501100001809National Natural Science Foundation of China. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)
- Published
- 2024
- Full Text
- View/download PDF
15. Amino Acid Metabolomic Profiles in Bovine Mammary Epithelial Cells under Essential Amino Acid Restriction
- Author
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Laura López-Diez, Camilo Calle-Velásquez, Mark D. Hanigan, and Zulma Tatiana Ruiz-Cortés
- Subjects
abductive analysis ,ASNS ,bovine ,casein ,EAA restriction ,GOT2 ,Veterinary medicine ,SF600-1100 ,Zoology ,QL1-991 - Abstract
Mammary epithelial cells (MECs) in culture are a useful model for elucidating mammary gland metabolism and changes that occur under different nutrient disponibility. MECs were exposed to different treatments: 100% EAA for 8 h and 24 h restriction (R); 2% EAA for 8 h and 24 h R; 2% EAA for 8 h and 24 h + 100% EAA for 8 h and 24 h restriction + re-feeding (R + RF). Western blotting and protein quantification was performed. The Kyoto Encyclopedia of Genes and Genomes (KEGG) software identified the amino acids (AAs) and signaling pathways. The chi-squared test, multiple classification analysis, and analysis of variance were used for the purification and identification of data. Intracellular casein levels were not affected. The KEGG analysis revealed that the important pathways of metabolism of AAs, which were involved in processes related to metabolism and biosynthesis of phenylalanine, tyrosine, and tryptophan (fumarate, acetyl-CoA, and tricarboxylic acid (TCA) cycle), were affected by both R and R + RF treatments, mainly through the glutamic-oxaloacetic transaminase-2 enzyme. Additionally, metabolic processes mediated by the mitochondrial malate dehydrogenase, S-adenosylmethionine synthetase, and asparagine synthase proteins positively regulated the carbohydrate pathway, pyruvate, and TCA cycles, as well as the metabolism of alanine, aspartate, and glutamate metabolism (carbohydrate and TCA cycle). We hypothesized that MECs have the capacity to utilize alternative pathways that ensure the availability of substrates for composing milk proteins.
- Published
- 2021
- Full Text
- View/download PDF
16. Association between CYP2E1 and GOT2 gene polymorphisms and susceptibility and low-dose N,N-dimethylformamide occupational exposure-induced liver injury.
- Author
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Jiang, Haiyue, Zhang, Xiaoyue, Shen, Jiayang, Zhang, Yu, Gu, Yiyang, Tian, Tian, Chu, Minjie, Zhuang, Xun, and Lian, Yulong
- Subjects
- *
LIVER injuries , *GENETIC polymorphisms , *DIMETHYLFORMAMIDE , *LOGISTIC regression analysis , *ALANINE aminotransferase , *AIR sampling apparatus - Abstract
Objective: To investigate the effects of the interactions between the CYP2E1 and GOT2 gene polymorphisms and N,N-dimethylformamide (DMF) on liver injury. Methods: A total of 672 DMF-exposed workers were randomly selected from two synthetic leather enterprises in Suzhou, China, for follow-up in a cohort study. Information on exposure to DMF in the air was collected through a fixed-point air sampler in the worker's breathing zone. The subjects were assessed every year during the period of 2010–2015, they underwent occupational health examinations. Alanine aminotransferase and aspartate aminotransferase levels were measured. Peripheral blood was collected and DNA was extracted. The genotypes rs2031920, rs3813867 and rs6413432 of the CYP2E1 gene and rs7204324 of the GOT2 gene were detected by PCR, and analyzed using the Chi-square test and logistic regression analysis. Results: Workers exposed to a high cumulative dose of DMF were significantly more likely than low-exposed workers to develop liver injury. No association was observed between rs2031920, rs3813867 and rs6413432 of the CYP2E1 gene and DMF-induced liver damage. However, the A allele of rs7204324 on the GOT2 gene may be a risk factor for susceptibility to DMF-induced liver injury. Conclusion: Polymorphisms of rs7204324 on GOT2 may play an important role in susceptibility to liver injury following exposure to DMF. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
17. Bi-allelic GOT2 Mutations Cause a Treatable Malate-Aspartate Shuttle-Related Encephalopathy.
- Author
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van Karnebeek, Clara D.M., Ramos, Rúben J., Wen, Xiao-Yan, Tarailo-Graovac, Maja, Gleeson, Joseph G., Skrypnyk, Cristina, Brand-Arzamendi, Koroboshka, Karbassi, Farhad, Issa, Mahmoud Y., van der Lee, Robin, Drögemöller, Britt I., Koster, Janet, Rousseau, Justine, Campeau, Philippe M., Wang, Youdong, Cao, Feng, Li, Meng, Ruiter, Jos, Ciapaite, Jolita, and Kluijtmans, Leo A.J.
- Subjects
- *
ASPARTATE aminotransferase , *ETIOLOGY of diseases , *NAD (Coenzyme) , *INBORN errors of metabolism - Abstract
Early-infantile encephalopathies with epilepsy are devastating conditions mandating an accurate diagnosis to guide proper management. Whole-exome sequencing was used to investigate the disease etiology in four children from independent families with intellectual disability and epilepsy, revealing bi-allelic GOT2 mutations. In-depth metabolic studies in individual 1 showed low plasma serine, hypercitrullinemia, hyperlactatemia, and hyperammonemia. The epilepsy was serine and pyridoxine responsive. Functional consequences of observed mutations were tested by measuring enzyme activity and by cell and animal models. Zebrafish and mouse models were used to validate brain developmental and functional defects and to test therapeutic strategies. GOT2 encodes the mitochondrial glutamate oxaloacetate transaminase. GOT2 enzyme activity was deficient in fibroblasts with bi-allelic mutations. GOT2, a member of the malate-aspartate shuttle, plays an essential role in the intracellular NAD(H) redox balance. De novo serine biosynthesis was impaired in fibroblasts with GOT2 mutations and GOT2-knockout HEK293 cells. Correcting the highly oxidized cytosolic NAD-redox state by pyruvate supplementation restored serine biosynthesis in GOT2-deficient cells. Knockdown of got2a in zebrafish resulted in a brain developmental defect associated with seizure-like electroencephalography spikes, which could be rescued by supplying pyridoxine in embryo water. Both pyridoxine and serine synergistically rescued embryonic developmental defects in zebrafish got2a morphants. The two treated individuals reacted favorably to their treatment. Our data provide a mechanistic basis for the biochemical abnormalities in GOT2 deficiency that may also hold for other MAS defects. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
18. Preventing BRCA1/ZBRK1 repressor complex binding to the GOT2 promoter results in accelerated aspartate biosynthesis and promotion of cell proliferation.
- Author
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Hong, Ruoxi, Zhang, Weimin, Xia, Xi, Zhang, Kai, Wang, Yan, Wu, Mengjiao, Fan, Jiawen, Li, Jinting, Xia, Wen, Xu, Fei, Chen, Jie, Wang, Shusen, and Zhan, Qimin
- Abstract
Breast cancer susceptibility gene 1 (BRCA1) has been implicated in modulating metabolism via transcriptional regulation. However, direct metabolic targets of BRCA1 and the underlying regulatory mechanisms are still unknown. Here, we identified several metabolic genes, including the gene which encodes glutamate‐oxaloacetate transaminase 2 (GOT2), a key enzyme for aspartate biosynthesis, which are repressed by BRCA1. We report that BRCA1 forms a co‐repressor complex with ZBRK1 that coordinately represses GOT2 expression via a ZBRK1 recognition element in the promoter of GOT2. Impairment of this complex results in upregulation of GOT2, which in turn increases aspartate and alpha ketoglutarate production, leading to rapid cell proliferation of breast cancer cells. Importantly, we found that GOT2 can serve as an independent prognostic factor for overall survival and disease‐free survival of patients with breast cancer, especially triple‐negative breast cancer. Interestingly, we also demonstrated that GOT2 overexpression sensitized breast cancer cells to methotrexate, suggesting a promising precision therapeutic strategy for breast cancer treatment. In summary, our findings reveal that BRCA1 modulates aspartate biosynthesis through transcriptional repression of GOT2, and provides a biological basis for treatment choices in breast cancer. Breast cancer susceptibility gene 1 (BRCA1) has been implicated in cell metabolism in previous studies, however, the underlying mechanisms are still unclear. Here, we demonstrated that BRCA1 forms a co‐repressor complex with ZBRK1 on the promoter of GOT2 via the ZBRK1 recognition element, and that BRCA1 deficiency promotes aspartate and α‐KG production and accelerates tumor cell growth together with GOT2 upregulation. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
19. A novel metabolism-related gene signature in patients with hepatocellular carcinoma.
- Author
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Ru B, Hu J, Zhang N, and Wan Q
- Subjects
- Humans, Area Under Curve, B-Lymphocytes, Butyryl-CoA Dehydrogenase, Carcinoma, Hepatocellular genetics, Liver Neoplasms genetics
- Abstract
Hepatocellular carcinoma (HCC) remains a global challenge as it is the sixth most common neoplasm worldwide and the third leading cause of cancer-related death. A key feature of HCC is abnormal metabolism, which promotes cancer cell proliferation, survival, invasion, and metastasis. However, the significance of metabolism-related genes (MRGs) in HCC remains to be elucidated. Here, we aim to establish a novel metabolism-related prognostic signature for the prediction of patient outcomes and to investigate the value of MRG expression in the prognostic prediction of HCC. In our research, a Metabolism-Related Risk Score (MRRS) model was constructed using 14 MRGs (DLAT, SEPHS1, ACADS, UCK2, GOT2, ADH4, LDHA, ME1, TXNRD1, B4GALT2, AK2, PTDSS2, CSAD, and AMD1). The Kaplan-Meier curve confirmed that the MRRS has a high accuracy in predicting the prognosis of HCC patients ( p < 0.001). According to the MRRS model, the area under the curve (AUC) values for predicting the prognosis of patients with hepatocellular carcinoma at 1, 3, and 5 years reached 0.829, 0.760, and 0.739, respectively. Functional analyses revealed that signaling pathways associated with the cell cycle were largely enriched by differential genes between high and low-risk groups. In addition, dendritic cells (DCs) ( p < 0.001), CD4+ T cells ( p < 0.01), CD8+ T cells ( p < 0.001), B cells ( p < 0.001), neutrophils ( p < 0.001), macrophages ( p < 0.001) had a higher proportion of infiltrates in high-risk populations. Low GOT2 expression is associated with poor prognosis in patients with hepatocellular carcinoma. Knockdown of GOT2 significantly increased the migration capacity of the Huh7 and MHCC97H hepatocellular carcinoma lines. Our research reveals that GOT2 is negatively related to the survival of patients with hepatocellular carcinoma and GOT2 may contribute to tumor progression by inhibiting the ability of tumor cells to migrate., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (©2023 Ru et al.)
- Published
- 2023
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20. Circular RNA circ_0003028 contributes to tumorigenesis by regulating GOT2 via miR-1298-5p in non-small cell lung cancer
- Author
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Jinjin Li, Yinfeng Gu, Changpeng Sun, Jie Ji, Hongjun Guan, and Yongxian Zhu
- Subjects
Male ,0301 basic medicine ,Lung Neoplasms ,Carcinogenesis ,Angiogenesis ,Cell ,Mice, Nude ,Apoptosis ,Bioengineering ,medicine.disease_cause ,mir-1298-5p ,Applied Microbiology and Biotechnology ,Flow cytometry ,Mice ,03 medical and health sciences ,0302 clinical medicine ,Circular RNA ,Carcinoma, Non-Small-Cell Lung ,Cell Line, Tumor ,medicine ,Animals ,Humans ,Aspartate Aminotransferases ,Lung ,non-small cell lung cancer ,Cell Proliferation ,Tube formation ,Gene knockdown ,medicine.diagnostic_test ,Chemistry ,Cell growth ,circ_0003028 ,RNA, Circular ,General Medicine ,got2 ,Gene Expression Regulation, Neoplastic ,MicroRNAs ,030104 developmental biology ,medicine.anatomical_structure ,030220 oncology & carcinogenesis ,Cancer research ,TP248.13-248.65 ,Research Article ,Research Paper ,Biotechnology - Abstract
Non-small cell lung cancer (NSCLC) is a common malignant tumor, with high morbidity and mortality. Circular RNA (circRNA) circ_0003028 was reported to be upregulated in NSCLC. This study is designed to explore the role and mechanism of circ_0003028 on NSCLC progression. In this work, circ_0003028, microRNA-1298-5p (miR-1298-5p), and glutamic oxaloacetic transaminase 2 (GOT2) level were detected by real-time quantitative polymerase chain reaction (RT-qPCR). The localization of circ_0003028 was analyzed by subcellular fractionation assay. Cell proliferation, colony number, cell cycle progression, apoptosis, migration, invasion, and angiogenesis were measured by Cell Counting Kit-8 (CCK-8), colony formation, flow cytometry, transwell, and tube formation assays. Protein levels of Beclin1, light chain 3 (LC3)-II/LC3-I, GOT2, proliferating cell nuclear antigen (PCNA) were examined by western blot assay. The binding relationship between miR-1298-5p and circ_0003028 or GOT2 was predicted by circular RNA Interactome or starbase and then verified by dual-luciferase reporter, RNA Immunoprecipitation (RIP), and RNA pull-down assays. The biological role of circ_0003028 on NSCLC tumor growth was examined by the xenograft tumor model in vivo. We reported that circ_0003028 and GOT2 were upregulated, and miR-1298-5p was decreased in NSCLC tissues and cells. Moreover, circ_0003028 knockdown curbed cell proliferative ability, migration, invasion, angiogenesis, and facilitate apoptosis and autophagy in NSCLC cells in vitro. Mechanical analysis discovered that circ_0003028 regulated GOT2 expression by sponging miR-1298-5p. Circ_0003028 silencing hindered the cell growth of NSCLC in vivo. Taken together, circ_0003028 knockdown could suppress NSCLC progression partly by regulating the miR-1298-5p/GOT2 axis, providing an underlying therapeutic target for NSCLC., graphic abstract
- Published
- 2021
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21. Expression of GOT2 Is Epigenetically Regulated by DNA Methylation and Correlates with Immune Infiltrates in Clear-Cell Renal Cell Carcinoma
- Author
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Edivaldo De Oliveira and Wallax Ferreira
- Subjects
Microbiology (medical) ,General Medicine ,KIRC ,GOT2 ,multi-omics ,epigenetics ,immune cell infiltration ,Molecular Biology ,Microbiology - Abstract
Clear cell renal cell carcinoma (KIRC) is the most common and highly malignant pathological type of kidney cancer, characterized by a profound metabolism dysregulation. As part of aspartate biosynthesis, mitochondrial GOT2 (glutamic-oxaloacetic transaminase 2) is essential for regulating cellular energy production and biosynthesis, linking multiple pathways. Nevertheless, the expression profile and prognostic significance of GOT2 in KIRC remain unclear. This study comprehensively analyzed the transcriptional levels, epigenetic regulation, correlation with immune infiltration, and prognosis of GOT2 in KIRC using rigorous bioinformatics analysis. We discovered that the expression levels of both mRNA and protein of GOT2 were remarkably decreased in KIRC tissues in comparison with normal tissues and were also significantly related to the clinical features and prognosis of KIRC. Remarkably, low GOT2 expression was positively associated with poorer overall survival (OS) and disease-free survival (DFS). Further analysis revealed that GOT2 downregulation is driven by DNA methylation in the promoter-related CpG islands. Finally, we also shed light on the influence of GOT2 expression in immune cell infiltration, suggesting that GOT2 may be a potential prognostic marker and therapeutic target for KIRC patients.
- Published
- 2022
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22. Low expression of GOT2 promotes tumor progress and predicts poor prognosis in hepatocellular carcinoma.
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Liang Q, Liu S, Yin F, Liu M, Wang L, Guo E, Lei L, Wu L, Yang Y, Zhang D, and Zeng X
- Subjects
- Humans, Cell Line, Tumor, Cell Movement genetics, Cell Proliferation genetics, Gene Expression Regulation, Neoplastic, Prognosis, Carcinoma, Hepatocellular diagnosis, Carcinoma, Hepatocellular genetics, Carcinoma, Hepatocellular metabolism, Liver Neoplasms diagnosis, Liver Neoplasms genetics, Liver Neoplasms metabolism
- Abstract
Background: To explore the biological function and the underlying mechanisms of GOT2 in hepatocellular carcinoma (HCC). Materials & methods: The expression level and prognostic value of GOT2 were examined using International Cancer Genome Consortium and International Cancer Proteogenome Consortium databases. The cell counting kit-8 method, clone formation, Transwell
® assays and western blotting were used to evaluate the effects of GOT2 on the biological function and autophagy of HCC cells. Results: The expression of GOT2 was downregulated in HCC tissues and correlated with poor prognosis of HCC patients. Knockdown of GOT2 promoted proliferation, migration and invasion of HCC cells and promoted cells' proliferation by inducing autophagy. Conclusion: GOT2 plays a tumor-inhibitory role in HCC and may be a potential therapeutic target for HCC.- Published
- 2023
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- View/download PDF
23. Combining single-cell and transcriptomic analysis revealed the immunomodulatory effect of GOT2 on a glutamine-dependent manner in cutaneous melanoma.
- Author
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Song L, Wei X, Zhang X, and Lu Y
- Abstract
Background: Reprogramming in glutamine metabolism is a hallmark of cancers, while its role in cutaneous melanoma has not been studied at great length. Methods: Here, we constructed a glutamine metabolism-related prognostic signature in cutaneous melanoma with a variety of bioinformatics methods according to the glutamine metabolism regulatory molecules. Moreover, experimental verification was carried out for the key gene. Results: We have identified two subgroups of cutaneous melanoma patients, each with different prognoses, immune characteristics, and genetic mutations. GOT2 was the most concerned key gene among the model genes. We verified its role in promoting tumor cell proliferation by CCK-8 and clone formation assays. Conclusion: Our study cast new light on the prognosis of cutaneous melanoma, and the internal mechanism regulating glutamine metabolism of GOT2 may provide a new avenue for treating the cutaneous melanoma disease precisely., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Song, Wei, Zhang and Lu.)
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- 2023
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24. The malate–aspartate shuttle (Borst cycle): How it started and developed into a major metabolic pathway
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Piet Borst
- Subjects
musculoskeletal diseases ,0301 basic medicine ,Cell Respiration ,Clinical Biochemistry ,Malates ,Respiratory chain ,Malate-aspartate shuttle ,Aspartate transaminase ,Mitochondrion ,Biochemistry ,GOT2 ,03 medical and health sciences ,0302 clinical medicine ,glycerol‐1‐P cycle ,Malate Dehydrogenase ,Genetics ,Animals ,Humans ,Aspartate Aminotransferases ,reductive carboxylation ,Critical Reviews ,Molecular Biology ,aspartate ,Aspartic Acid ,biology ,Chemistry ,fungi ,NADH/NAD ratio ,Critical Review ,Cell Biology ,Malate dehydrogenase 1 ,Mitochondria ,body regions ,Cytosol ,MAS ,030104 developmental biology ,citrate‐malate cycle ,030220 oncology & carcinogenesis ,Mutation ,biology.protein ,inborn errors ,lipids (amino acids, peptides, and proteins) ,NAD+ kinase ,Metabolism, Inborn Errors ,hormones, hormone substitutes, and hormone antagonists - Abstract
This article presents a personal and critical review of the history of the malate–aspartate shuttle (MAS), starting in 1962 and ending in 2020. The MAS was initially proposed as a route for the oxidation of cytosolic NADH by the mitochondria in Ehrlich ascites cell tumor lacking other routes, and to explain the need for a mitochondrial aspartate aminotransferase (glutamate oxaloacetate transaminase 2 [GOT2]). The MAS was soon adopted in the field as a major pathway for NADH oxidation in mammalian tissues, such as liver and heart, even though the energetics of the MAS remained a mystery. Only in the 1970s, LaNoue and coworkers discovered that the efflux of aspartate from mitochondria, an essential step in the MAS, is dependent on the proton‐motive force generated by the respiratory chain: for every aspartate effluxed, mitochondria take up one glutamate and one proton. This makes the MAS in practice uni‐directional toward oxidation of cytosolic NADH, and explains why the free NADH/NAD ratio is much higher in the mitochondria than in the cytosol. The MAS is still a very active field of research. Most recently, the focus has been on the role of the MAS in tumors, on cells with defects in mitochondria and on inborn errors in the MAS. The year 2019 saw the discovery of two new inborn errors in the MAS, deficiencies in malate dehydrogenase 1 and in aspartate transaminase 2 (GOT2). This illustrates the vitality of ongoing MAS research.
- Published
- 2020
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25. Amino Acid Metabolomic Profiles in Bovine Mammary Epithelial Cells under Essential Amino Acid Restriction
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López-Diez, Laura, Calle-Velásquez, Camilo, Hanigan, Mark D., Ruiz-Cortés, Zulma Tatiana, López-Diez, Laura, Calle-Velásquez, Camilo, Hanigan, Mark D., and Ruiz-Cortés, Zulma Tatiana
- Abstract
Mammary epithelial cells (MECs) in culture are a useful model for elucidating mammary gland metabolism and changes that occur under different nutrient disponibility. MECs were exposed to different treatments: 100% EAA for 8 h and 24 h restriction (R); 2% EAA for 8 h and 24 h R; 2% EAA for 8 h and 24 h + 100% EAA for 8 h and 24 h restriction + re-feeding (R + RF). Western blotting and protein quantification was performed. The Kyoto Encyclopedia of Genes and Genomes (KEGG) software identified the amino acids (AAs) and signaling pathways. The chi-squared test, multiple classification analysis, and analysis of variance were used for the purification and identification of data. Intracellular casein levels were not affected. The KEGG analysis revealed that the important pathways of metabolism of AAs, which were involved in processes related to metabolism and biosynthesis of phenylalanine, tyrosine, and tryptophan (fumarate, acetyl-CoA, and tricarboxylic acid (TCA) cycle), were affected by both R and R + RF treatments, mainly through the glutamic-oxaloacetic transaminase-2 enzyme. Additionally, metabolic processes mediated by the mitochondrial malate dehydrogenase, S-adenosylmethionine synthetase, and asparagine synthase proteins positively regulated the carbohydrate pathway, pyruvate, and TCA cycles, as well as the metabolism of alanine, aspartate, and glutamate metabolism (carbohydrate and TCA cycle). We hypothesized that MECs have the capacity to utilize alternative pathways that ensure the availability of substrates for composing milk proteins.
- Published
- 2021
- Full Text
- View/download PDF
26. Amino Acid Metabolomic Profiles in Bovine Mammary Epithelial Cells under Essential Amino Acid Restriction
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Dairy Science, López-Diez, Laura, Calle-Velásquez, Camilo, Hanigan, Mark D., Ruiz-Cortés, Zulma Tatiana, Dairy Science, López-Diez, Laura, Calle-Velásquez, Camilo, Hanigan, Mark D., and Ruiz-Cortés, Zulma Tatiana
- Abstract
Mammary epithelial cells (MECs) in culture are a useful model for elucidating mammary gland metabolism and changes that occur under different nutrient disponibility. MECs were exposed to different treatments: 100% EAA for 8 h and 24 h restriction (R); 2% EAA for 8 h and 24 h R; 2% EAA for 8 h and 24 h + 100% EAA for 8 h and 24 h restriction + re-feeding (R + RF). Western blotting and protein quantification was performed. The Kyoto Encyclopedia of Genes and Genomes (KEGG) software identified the amino acids (AAs) and signaling pathways. The chi-squared test, multiple classification analysis, and analysis of variance were used for the purification and identification of data. Intracellular casein levels were not affected. The KEGG analysis revealed that the important pathways of metabolism of AAs, which were involved in processes related to metabolism and biosynthesis of phenylalanine, tyrosine, and tryptophan (fumarate, acetyl-CoA, and tricarboxylic acid (TCA) cycle), were affected by both R and R + RF treatments, mainly through the glutamic-oxaloacetic transaminase-2 enzyme. Additionally, metabolic processes mediated by the mitochondrial malate dehydrogenase, S-adenosylmethionine synthetase, and asparagine synthase proteins positively regulated the carbohydrate pathway, pyruvate, and TCA cycles, as well as the metabolism of alanine, aspartate, and glutamate metabolism (carbohydrate and TCA cycle). We hypothesized that MECs have the capacity to utilize alternative pathways that ensure the availability of substrates for composing milk proteins.
- Published
- 2021
27. The Potential Relationship Between HIF-1α and Amino Acid Metabolism After Hypoxic Ischemia and Dual Effects on Neurons
- Author
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Yang Zheng, Xiaoming Wang, and Kexin Li
- Subjects
chemistry.chemical_classification ,hypoxia inducible factor ,biology ,hypoxic-ischemic injury ,GCLM ,General Neuroscience ,Neurosciences. Biological psychiatry. Neuropsychiatry ,amino acid metabolism ,GOT2 ,Molecular biology ,Glutathione synthase ,Amino acid ,Doublecortin ,neurogenesis ,GCLC ,Hypoxia-inducible factors ,chemistry ,biology.protein ,NeuN ,Neuroscience ,Original Research ,neural plasticity ,RC321-571 - Abstract
Hypoxia inducible factor (HIF) is one of the major transcription factors through which cells and tissues adapt to hypoxic-ischemic injury. However, the specific mechanism by which HIF regulates amino acid metabolism and its effect on neurons during hypoxic ischemia (HI) have remained unclear. This study analyzed the changes in cerebral metabolism of amino acids after HI by using 1H-MRS and investigated the relationship between the changes in cerebral metabolism of amino acids and HIF-1α as well as the potential effects on neurons. Newborn pigs were used as an HI model in this study. Twenty-eight newborn Yorkshire pigs (male, 1.0–1.5 kg) aged 3–5 days were selected and randomly divided into experimental groups tested at 0–2 h (n = 4), 2–6 h (n = 4), 6–12 h (n = 4), 12–24 h (n = 4), 24–48 h (n = 4), and 48–72 h (n = 4) after HI, and a control group (n = 4). After the modeling was completed, 1H-MRS imaging was conducted, followed by immunohistochemical staining of HIF-1α, NeuN, and doublecortin (DCX), and immunofluorescence of glutamic oxaloacetic transaminase (GOT)-1, GOT2, glutathione synthase (GS), glutamate-cysteine ligase catalytic subunit (GCLC), and glutamate-cysteine ligase modifier subunit (GCLM) in brain tissues. The expression of HIF-1α exhibited two increases after HI injury. The first time was opposite to the trends of change of GOT2, aspartic acid, and the number of neurons, while the second was consistent with these trends, suggesting that HIF-1α may have a two-way induction effect on neurons by regulating GOT2 after HI. HIF-1α was closely related to GCLM expression, and GSH level was correlated with the number of hippocampal neurons, indicating that HIF-1α may regulate GCLM to promote GSH synthesis and additionally play a neuroprotective role.
- Published
- 2021
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28. Preventing <scp>BRCA</scp> 1/ <scp>ZBRK</scp> 1 repressor complex binding to the GOT2 promoter results in accelerated aspartate biosynthesis and promotion of cell proliferation
- Author
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Jie Chen, Mengjiao Wu, Weimin Zhang, Ruoxi Hong, Wen Xia, Xi Xia, Yan Wang, Qimin Zhan, Shusen Wang, Jiawen Fan, Fei Xu, Jinting Li, and Kai Zhang
- Subjects
0301 basic medicine ,Cancer Research ,Transcription, Genetic ,endocrine system diseases ,Mice ,0302 clinical medicine ,Alpha ketoglutarate ,Transcriptional regulation ,Promoter Regions, Genetic ,skin and connective tissue diseases ,Research Articles ,aspartate ,BRCA1 Protein ,General Medicine ,Middle Aged ,lcsh:Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,Gene Expression Regulation, Neoplastic ,Phenotype ,Oncology ,030220 oncology & carcinogenesis ,Ketoglutaric Acids ,Molecular Medicine ,Female ,GOT2 ,Research Article ,Protein Binding ,ZBRK1 ,Repressor ,Breast Neoplasms ,Biology ,Models, Biological ,lcsh:RC254-282 ,03 medical and health sciences ,breast cancer ,Breast cancer ,Downregulation and upregulation ,Cell Line, Tumor ,Biomarkers, Tumor ,Genetics ,medicine ,Animals ,Humans ,Gene ,Aspartate Aminotransferase, Mitochondrial ,Cell Proliferation ,Aspartic Acid ,Cell growth ,BRCA1 ,medicine.disease ,Repressor Proteins ,HEK293 Cells ,Methotrexate ,030104 developmental biology ,Cancer research ,co‐repressor - Abstract
Breast cancer susceptibility gene 1 (BRCA1) has been implicated in modulating metabolism via transcriptional regulation. However, direct metabolic targets of BRCA1 and the underlying regulatory mechanisms are still unknown. Here, we identified several metabolic genes, including the gene which encodes glutamate‐oxaloacetate transaminase 2 (GOT2), a key enzyme for aspartate biosynthesis, which are repressed by BRCA1. We report that BRCA1 forms a co‐repressor complex with ZBRK1 that coordinately represses GOT 2 expression via a ZBRK1 recognition element in the promoter of GOT2. Impairment of this complex results in upregulation of GOT2, which in turn increases aspartate and alpha ketoglutarate production, leading to rapid cell proliferation of breast cancer cells. Importantly, we found that GOT2 can serve as an independent prognostic factor for overall survival and disease‐free survival of patients with breast cancer, especially triple‐negative breast cancer. Interestingly, we also demonstrated that GOT2 overexpression sensitized breast cancer cells to methotrexate, suggesting a promising precision therapeutic strategy for breast cancer treatment. In summary, our findings reveal that BRCA1 modulates aspartate biosynthesis through transcriptional repression of GOT2, and provides a biological basis for treatment choices in breast cancer.
- Published
- 2019
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29. Bi-allelic GOT2 Mutations Cause a Treatable Malate-Aspartate Shuttle-Related Encephalopathy
- Author
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Nanda M. Verhoeven-Duif, Janet Koster, Hans R. Waterham, Wyeth W. Wasserman, Justine Rousseau, Judith J.M. Jans, Youdong Wang, Colin J. D. Ross, Mahmoud Y. Issa, Liesbeth T. Wintjes, Maja Tarailo-Graovac, Leo A. J. Kluijtmans, Clara D.M. van Karnebeek, Michèl A.A.P. Willemsen, Jos P.N. Ruiter, Xiao-Yan Wen, Ron A. Wevers, Philippe M. Campeau, Farhad Karbassi, Cristina Skrypnyk, Marleen C. D. G. Huigen, Koroboshka Brand-Arzamendi, Feng Cao, Richard J. Rodenburg, Zhengping Jia, Meng Li, Ronald J.A. Wanders, Ruben Ramos, Britt I. Drögemöller, Maha S. Zaki, Joseph G. Gleeson, Jolita Ciapaite, Robin van der Lee, AGEM - Amsterdam Gastroenterology Endocrinology Metabolism, ANS - Cellular & Molecular Mechanisms, Paediatric Metabolic Diseases, AGEM - Inborn errors of metabolism, Laboratory Genetic Metabolic Diseases, ARD - Amsterdam Reproduction and Development, APH - Methodology, Pediatric surgery, Amsterdam Neuroscience - Brain Imaging, Amsterdam Reproduction & Development (AR&D), and Laboratory Medicine
- Subjects
0301 basic medicine ,Male ,Malates ,Malate-aspartate shuttle ,Other Research Radboud Institute for Molecular Life Sciences [Radboudumc 0] ,Fatty Acid-Binding Proteins ,GOT2 ,Article ,Serine ,03 medical and health sciences ,Mice ,All institutes and research themes of the Radboud University Medical Center ,0302 clinical medicine ,Exome Sequencing ,Genetics ,medicine ,Journal Article ,pyridoxine responsive epilepsy ,Animals ,Humans ,Child ,Zebrafish ,Genetics (clinical) ,Alleles ,Gene knockdown ,Aspartic Acid ,Brain Diseases ,biology ,HEK 293 cells ,Metabolic Disorders Radboud Institute for Molecular Life Sciences [Radboudumc 6] ,Hyperammonemia ,Disorders of movement Donders Center for Medical Neuroscience [Radboudumc 3] ,biology.organism_classification ,Pyridoxine ,medicine.disease ,3. Good health ,Cell biology ,mitochondriopathy ,030104 developmental biology ,HEK293 Cells ,malate-aspartate shuttle ,Child, Preschool ,Gene Knockdown Techniques ,Mutation ,Female ,metabolism ,redox imbalancetreatment ,030217 neurology & neurosurgery ,medicine.drug - Abstract
Early-infantile encephalopathies with epilepsy are devastating conditions mandating an accurate diagnosis to guide proper management. Whole-exome sequencing was used to investigate the disease etiology in four children from independent families with intellectual disability and epilepsy, revealing bi-allelic GOT2 mutations. In-depth metabolic studies in individual 1 showed low plasma serine, hypercitrullinemia, hyperlactatemia, and hyperammonemia. The epilepsy was serine and pyridoxine responsive. Functional consequences of observed mutations were tested by measuring enzyme activity and by cell and animal models. Zebrafish and mouse models were used to validate brain developmental and functional defects and to test therapeutic strategies. GOT2 encodes the mitochondrial glutamate oxaloacetate transaminase. GOT2 enzyme activity was deficient in fibroblasts with bi-allelic mutations. GOT2, a member of the malate-aspartate shuttle, plays an essential role in the intracellular NAD(H) redox balance. De novo serine biosynthesis was impaired in fibroblasts with GOT2 mutations and GOT2-knockout HEK293 cells. Correcting the highly oxidized cytosolic NAD-redox state by pyruvate supplementation restored serine biosynthesis in GOT2-deficient cells. Knockdown of got2a in zebrafish resulted in a brain developmental defect associated with seizure-like electroencephalography spikes, which could be rescued by supplying pyridoxine in embryo water. Both pyridoxine and serine synergistically rescued embryonic developmental defects in zebrafish got2a morphants. The two treated individuals reacted favorably to their treatment. Our data provide a mechanistic basis for the biochemical abnormalities in GOT2 deficiency that may also hold for other MAS defects.
- Published
- 2019
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30. Genetic Analysis of Tryptophan Metabolism Genes in Sporadic Amyotrophic Lateral Sclerosis
- Author
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Jennifer A. Fifita, Sandrine Chan Moi Fat, Emily P. McCann, Kelly L. Williams, Natalie A. Twine, Denis C. Bauer, Dominic B. Rowe, Roger Pamphlett, Matthew C. Kiernan, Vanessa X. Tan, Ian P. Blair, and Gilles J. Guillemin
- Subjects
0301 basic medicine ,Kynurenine pathway ,Immunology ,Biology ,GOT2 ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,kynurenine pathway (KP) ,medicine ,Humans ,Immunology and Allergy ,Genetic Predisposition to Disease ,Amyotrophic lateral sclerosis ,Gene ,Neuroinflammation ,Original Research ,Genetics ,TPH1 ,TPH2 ,Whole Genome Sequencing ,Amyotrophic Lateral Sclerosis ,Tryptophan ,whole-genome sequence (WGS) ,RC581-607 ,medicine.disease ,sporadic amyotrophic lateral sclerosis (SALS) ,serotonin ,030104 developmental biology ,chemistry ,Immunologic diseases. Allergy ,030217 neurology & neurosurgery ,Quinolinic acid - Abstract
The essential amino acid tryptophan (TRP) is the initiating metabolite of the kynurenine pathway (KP), which can be upregulated by inflammatory conditions in cells. Neuroinflammation-triggered activation of the KP and excessive production of the KP metabolite quinolinic acid are common features of multiple neurodegenerative diseases, including amyotrophic lateral sclerosis (ALS). In addition to its role in the KP, genes involved in TRP metabolism, including its incorporation into proteins, and synthesis of the neurotransmitter serotonin, have also been genetically and functionally linked to these diseases. ALS is a late onset neurodegenerative disease that is classified as familial or sporadic, depending on the presence or absence of a family history of the disease. Heritability estimates support a genetic basis for all ALS, including the sporadic form of the disease. However, the genetic basis of sporadic ALS (SALS) is complex, with the presence of multiple gene variants acting to increase disease susceptibility and is further complicated by interaction with potential environmental factors. We aimed to determine the genetic contribution of 18 genes involved in TRP metabolism, including protein synthesis, serotonin synthesis and the KP, by interrogating whole-genome sequencing data from 614 Australian sporadic ALS cases. Five genes in the KP (AFMID, CCBL1, GOT2, KYNU, HAAO) were found to have either novel protein-altering variants, and/or a burden of rare protein-altering variants in SALS cases compared to controls. Four genes involved in TRP metabolism for protein synthesis (WARS) and serotonin synthesis (TPH1, TPH2, MAOA) were also found to carry novel variants and/or gene burden. These variants may represent ALS risk factors that act to alter the KP and lead to neuroinflammation. These findings provide further evidence for the role of TRP metabolism, the KP and neuroinflammation in ALS disease pathobiology.
- Published
- 2021
- Full Text
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31. Inborn disorders of the malate aspartate shuttle
- Author
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Judith J.M. Jans, Ronald J.A. Wanders, Melissa H. Broeks, Nanda M. Verhoeven-Duif, and Clara D.M. van Karnebeek
- Subjects
Cell Respiration ,Malates ,Malate-aspartate shuttle ,Review Article ,Mitochondrion ,GOT2 ,AGC1 ,AGC2 ,malate aspartate shuttle ,Serine ,inborn metabolic disorder ,Malate Dehydrogenase ,Genetics ,Animals ,Humans ,Glycolysis ,Aspartate Aminotransferases ,Inner mitochondrial membrane ,Review Articles ,Genetics (clinical) ,Aspartic Acid ,Chemistry ,NAD(H) ,Infant ,Mitochondria ,Metabolic pathway ,Biochemistry ,redox ,lipids (amino acids, peptides, and proteins) ,NAD+ kinase ,MDH2 ,Spasms, Infantile ,Metabolism, Inborn Errors ,MDH1 - Abstract
Over the last few years, various inborn disorders have been reported in the malate aspartate shuttle (MAS). The MAS consists of 4 metabolic enzymes and 2 transporters, one of them having two isoforms that are expressed in different tissues. Together they form a biochemical pathway that shuttles electrons from the cytosol into mitochondria, as the inner mitochondrial membrane is impermeable to the electron carrier NADH. By shuttling NADH across the mitochondrial membrane in the form of a reduced metabolite (malate), the MAS plays an important role in mitochondrial respiration. In addition, the MAS maintains the cytosolic NAD+ /NADH redox balance, by using redox reactions for the transfer of electrons. This explains why the MAS is also important in sustaining cytosolic redox-dependent metabolic pathways, such as glycolysis and serine biosynthesis. The current review provides insights into the clinical and biochemical characteristics of MAS deficiencies. To date, 5 out of 7 potential MAS deficiencies have been reported. Most of them present with a clinical phenotype of infantile epileptic encephalopathy. Although not specific, biochemical characteristics include high lactate, high glycerol 3-phosphate, a disturbed redox balance, TCA abnormalities, high ammonia and low serine, which may be helpful in reaching a diagnosis in patients with an infantile epileptic encephalopathy. Current implications for treatment include a ketogenic diet, as well as serine and vitamin B6 supplementation. This article is protected by copyright. All rights reserved.
- Published
- 2021
32. Animals
- Author
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Camilo Calle-Velásquez, Zulma Tatiana Ruiz-Cortés, Mark D. Hanigan, Laura López-Diez, and Dairy Science
- Subjects
Veterinary medicine ,GOT2 ,casein ,Article ,chemistry.chemical_compound ,Biosynthesis ,SF600-1100 ,Tyrosine ,Essential amino acid ,chemistry.chemical_classification ,Alanine ,General Veterinary ,bovine ,Metabolism ,MAT2A ,Amino acid ,Citric acid cycle ,ASNS ,chemistry ,Biochemistry ,QL1-991 ,Animal Science and Zoology ,EAA restriction ,mammary epithelial cell ,MDH2 ,Zoology ,abductive analysis - Abstract
Mammary epithelial cells (MECs) in culture are a useful model for elucidating mammary gland metabolism and changes that occur under different nutrient disponibility. MECs were exposed to different treatments: 100% EAA for 8 h and 24 h restriction (R), 2% EAA for 8 h and 24 h R, 2% EAA for 8 h and 24 h + 100% EAA for 8 h and 24 h restriction + re-feeding (R + RF). Western blotting and protein quantification was performed. The Kyoto Encyclopedia of Genes and Genomes (KEGG) software identified the amino acids (AAs) and signaling pathways. The chi-squared test, multiple classification analysis, and analysis of variance were used for the purification and identification of data. Intracellular casein levels were not affected. The KEGG analysis revealed that the important pathways of metabolism of AAs, which were involved in processes related to metabolism and biosynthesis of phenylalanine, tyrosine, and tryptophan (fumarate, acetyl-CoA, and tricarboxylic acid (TCA) cycle), were affected by both R and R + RF treatments, mainly through the glutamic-oxaloacetic transaminase-2 enzyme. Additionally, metabolic processes mediated by the mitochondrial malate dehydrogenase, S-adenosylmethionine synthetase, and asparagine synthase proteins positively regulated the carbohydrate pathway, pyruvate, and TCA cycles, as well as the metabolism of alanine, aspartate, and glutamate metabolism (carbohydrate and TCA cycle). We hypothesized that MECs have the capacity to utilize alternative pathways that ensure the availability of substrates for composing milk proteins.
- Published
- 2021
- Full Text
- View/download PDF
33. Circ_0006220 Contributes to NSCLC Progression through miR-342-3p/GOT2 Axis.
- Author
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Tang J, Li X, Zhao L, Hui J, and Ding N
- Subjects
- Humans, Treatment Outcome, Apoptosis, Cell Proliferation, Carcinoma, Non-Small-Cell Lung genetics, Lung Neoplasms genetics, MicroRNAs genetics
- Abstract
Purpose: Dysregulated circular RNAs (circRNAs) have shown crucial modulatory functions in tumorigenesis, containing non-small cell lung cancer (NSCLC). The purpose of this study was to explore the biological functions and regulatory theory of circ_0006220 in NSCLC., Methods: Reverse transcription-quantitative polymerase chain reaction and Western blot assay were conducted to measure RNA and protein expression, respectively. A total of 73 cases of NSCLC tumor samples were collected for expression analysis, and A-549 and NCI-H1299 cell lines were used for functional experiments. Cell proliferation was assessed by cell counting kit-8 assay, colony formation assay, 5-ethynyl-2'-deoxyuridine assay, and flow cytometry. Cell apoptosis, motility, and angiogenesis ability were analyzed by flow cytometry, transwell assays, and capillary-like network formation assay. Dual-luciferase reporter assay and RNA immunoprecipitation assay were conducted to verify the target relationships., Results: Circ_0006220 was highly expressed in NSCLC tissues and cell lines. Circ_0006220 silencing inhibited the proliferation, migration, invasion, and angiogenesis but induced the apoptosis of NSCLC cells. Circ_0006220 acted as a microRNA-342-3p (miR-342-3p) sponge, and circ_0006220 knockdown-induced changes on the phenotypes of NSCLC cells were largely overturned by the knockdown of miR-342-3p. miR-342-3p interacted with the 3' untranslated region of glutamic-oxaloacetic transaminase 2 (GOT2), and GOT2 overexpression largely diminished miR-342-3p overexpression-mediated influences in NSCLC cells. Circ_0006220 could up-regulate GOT2 expression by sponging miR-342-3p., Conclusion: Circ_0006220 promoted the malignant behaviors of NSCLC cells through mediating the miR-342-3p/GOT2 regulation cascade.
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- 2023
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34. Dysregulated Provision of Oxidisable Substrates to the Mitochondria in ME/CFS Lymphoblasts
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Oana Sanislav, Paul R. Fisher, Paige K. Smith, Claire Y. Allan, Sarah J. Annesley, and Daniel Missailidis
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Male ,Proteome ,Mitochondrion ,Oxidative Phosphorylation ,Substrate Specificity ,lcsh:Chemistry ,transcriptomics ,Glycolysis ,Lymphocytes ,amino acid catabolism ,lcsh:QH301-705.5 ,Beta oxidation ,Spectroscopy ,Fatigue Syndrome, Chronic ,Chemistry ,General Medicine ,Middle Aged ,glycolysis ,Computer Science Applications ,mitochondria ,Biochemistry ,Female ,Oxidation-Reduction ,ME/CFS ,Metabolic Networks and Pathways ,Myalgic Encephalomyelitis ,Adult ,Proteasome Endopeptidase Complex ,GOT2 ,Catalysis ,Article ,beta-oxidation ,Inorganic Chemistry ,proteomics ,Humans ,RNA, Messenger ,Physical and Theoretical Chemistry ,Molecular Biology ,TCA cycle ,Mitochondrial transport ,Aged ,Organic Chemistry ,Metabolism ,Glutamine ,Citric acid cycle ,Protein Subunits ,lcsh:Biology (General) ,lcsh:QD1-999 ,Gene Expression Regulation ,Transcriptome ,metabolism - Abstract
Although understanding of the biomedical basis of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is growing, the underlying pathological mechanisms remain uncertain. We recently reported a reduction in the proportion of basal oxygen consumption due to ATP synthesis by Complex V in ME/CFS patient-derived lymphoblast cell lines, suggesting mitochondrial respiratory inefficiency. This was accompanied by elevated respiratory capacity, elevated mammalian target of rapamycin complex 1 (mTORC1) signaling activity and elevated expression of enzymes involved in the TCA cycle, fatty acid β-oxidation and mitochondrial transport. These and other observations led us to hypothesise the dysregulation of pathways providing the mitochondria with oxidisable substrates. In our current study, we aimed to revisit this hypothesis by applying a combination of whole-cell transcriptomics, proteomics and energy stress signaling activity measures using subsets of up to 34 ME/CFS and 31 healthy control lymphoblast cell lines from our growing library. While levels of glycolytic enzymes were unchanged in accordance with our previous observations of unaltered glycolytic rates, the whole-cell proteomes of ME/CFS lymphoblasts contained elevated levels of enzymes involved in the TCA cycle (p = 1.03 × 10−4), the pentose phosphate pathway (p = 0.034, G6PD p = 5.5 × 10−4), mitochondrial fatty acid β-oxidation (p = 9.2 × 10−3), and degradation of amino acids including glutamine/glutamate (GLS p = 0.034, GLUD1 p = 0.048, GOT2 p = 0.026), branched-chain amino acids (BCKDHA p = 0.028, BCKDHB p = 0.031) and essential amino acids (FAH p = 0.036, GCDH p = 0.006). The activity of the major cellular energy stress sensor, AMPK, was elevated but the increase did not reach statistical significance. The results suggest that ME/CFS metabolism is dysregulated such that alternatives to glycolysis are more heavily utilised than in controls to provide the mitochondria with oxidisable substrates.
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- 2021
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35. The Pancreatic Tumor Microenvironment Compensates for Loss of GOT2
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Marina Pasca di Magliano, Yatrik M. Shah, David B. Lombard, Peter Sajjakulnukit, Stefanie Galbán, Barbara S. Nelson, Amy L. Myers, Sarah E. Ackenhusen, Xiaohua Gao, Zeribe C. Nwosu, Yaqing Zhang, Howard C. Crawford, Christopher J. Halbrook, Jennifer A. Jiménez, Hui-Ju Wen, Lin Lin, David Piwnica-Worms, Samuel A. Kerk, Brandon Chen, Anthony Robinson, Megan T. Hoffman, Li Zhang, Johanna Ramos, Anthony Andren, Nina Steele, Haoqiang Ying, Daniel Long, Galloway Thurston, Samantha Kemp, and Costas A. Lyssiotis
- Subjects
Tumor microenvironment ,Chemistry ,In vivo ,Pancreatic tumor ,Cancer research ,medicine ,Cancer-Associated Fibroblasts ,Metabolism ,medicine.disease ,Carcinogenesis ,medicine.disease_cause ,GOT2 ,Intracellular - Abstract
The tumor microenvironment (TME) in pancreatic ductal adenocarcinoma (PDA) restricts vascularization and, consequently, access to blood-derived nutrients and oxygen, which impacts tumor growth. Intracellular redox imbalance is another restraint on cellular proliferation, yet it is unknown if the TME contributes to the maintenance of redox homeostasis in PDA cells. Here, we demonstrate that the loss of mitochondrial glutamate-oxaloacetate transaminase 2 (GOT2), a component in the malate-aspartate shuttle, disturbs redox homeostasis and halts proliferation of PDA cells in vitro. In contrast, GOT2 inhibition has no effect on in vivo tumor growth or tumorigenesis in an autochthonous model. We propose that this discrepancy is explained by heterocellular pyruvate exchange from the TME, including from cancer associated fibroblasts. More broadly, pyruvate similarly confers resistance to inhibitors of mitochondrial respiration. Genetic or pharmacologic inhibition of pyruvate uptake or metabolism abrogated pyruvate-mediated alleviation of reductive stress from NADH buildup. In sum, this work describes a potential resistance mechanism mediated by metabolic crosstalk within the pancreatic TME. These findings have important implications for metabolic treatment strategies since several mitochondrial inhibitors are currently in clinical trials for PDA and other cancers.
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- 2020
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36. Survival-Associated Metabolic Genes in Human Papillomavirus-Positive Head and Neck Cancers
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Farhad Ghasemi, Martin Prusinkiewicz, Hanna Maekebay, Mackenzie J. Dodge, Anthony C. Nichols, Steven F. Gameiro, Peter Y.F. Zeng, John W. Barrett, and Joe S. Mymryk
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0301 basic medicine ,Human Papillomavirus Positive ,Cancer Research ,Cellular respiration ,Cell ,cancer metabolism ,GOT2 ,lcsh:RC254-282 ,Article ,03 medical and health sciences ,0302 clinical medicine ,Gene expression ,medicine ,Glycolysis ,human papillomavirus ,Gene ,business.industry ,Head and neck cancer ,cellular respiration ,virus diseases ,glycolysis ,TCGA ,medicine.disease ,lcsh:Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,3. Good health ,stomatognathic diseases ,030104 developmental biology ,medicine.anatomical_structure ,Oncology ,030220 oncology & carcinogenesis ,Cancer research ,head and neck cancer ,business - Abstract
Human papillomavirus (HPV) causes an increasing number of head and neck squamous cell carcinomas (HNSCCs). Altered metabolism contributes to patient prognosis, but the impact of HPV status on HNSCC metabolism remains relatively uncharacterized. We hypothesize that metabolism-related gene expression differences unique to HPV-positive HNSCC influences patient survival. The Cancer Genome Atlas RNA-seq data from primary HNSCC patient samples were categorized as 73 HPV-positive, 442 HPV-negative, and 43 normal-adjacent control tissues. We analyzed 229 metabolic genes and identified numerous differentially expressed genes between HPV-positive and negative HNSCC patients. HPV-positive carcinomas exhibited lower expression levels of genes involved in glycolysis and higher levels of genes involved in the tricarboxylic acid cycle, oxidative phosphorylation, and &beta, oxidation than the HPV-negative carcinomas. Importantly, reduced expression of the metabolism-related genes SDHC, COX7A1, COX16, COX17, ELOVL6, GOT2, and SLC16A2 were correlated with improved patient survival only in the HPV-positive group. This work suggests that specific transcriptional alterations in metabolic genes may serve as predictive biomarkers of patient outcome and identifies potential targets for novel therapeutic intervention in HPV-positive head and neck cancers.
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- 2020
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37. STXBP3 and GOT2 predict immunological activity in acute allograft rejection.
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Yao Q, Wang C, Wang Y, Xiang W, Chen Y, Zhou Q, Chen J, Jiang H, and Chen D
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- Humans, Graft Rejection, Transplantation, Homologous, Kidney, Allografts, Kidney Transplantation adverse effects
- Abstract
Background: Acute allograft rejection (AR) following renal transplantation contributes to chronic rejection and allograft dysfunction. The current diagnosis of AR remains dependent on renal allograft biopsy which cannot immediately detect renal allograft injury in the presence of AR. In this study, sensitive biomarkers for AR diagnosis were investigated and developed to protect renal function., Methods: We analyzed pre- and postoperative data from five databases combined with our own data to identify the key differently expressed genes (DEGs). Furthermore, we performed a bioinformatics analysis to determine the immune characteristics of DEGs. The expression of key DEGs was further confirmed using the real-time quantitative PCR (RT-qPCR), enzyme-linked immunosorbent assay (ELISA), and immunohistochemical (IHC) staining in patients with AR. ROC curves analysis was used to estimate the performance of key DEGs in the early diagnosis of AR., Results: We identified glutamic-oxaloacetic transaminase 2 (GOT2) and syntaxin binding protein 3 (STXBP3) as key DEGs. The higher expression of STXBP3 and GOT2 in patients with AR was confirmed using RT-qPCR, ELISA, and IHC staining. ROC curve analysis also showed favorable values of STXBP3 and GOT2 for the diagnosis of early stage AR., Conclusions: STXBP3 and GOT2 could reflect the immunological status of patients with AR and have strong potential for the diagnosis of early-stage AR., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Yao, Wang, Wang, Xiang, Chen, Zhou, Chen, Jiang and Chen.)
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- 2022
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38. Aspartate availability limits hematopoietic stem cell function during hematopoietic regeneration
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Michalis Agathocleous, Misty S. Martin-Sandoval, Zhiyu Zhao, Sean J. Morrison, Wen Gu, Matthias Eckhardt, Thomas P. Mathews, Le Qi, and Salma Merchant
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Aspartic Acid ,endocrine system diseases ,Asparagine synthetase ,nutritional and metabolic diseases ,Hematopoietic stem cell ,hemic and immune systems ,Cell Biology ,Biology ,Hematopoietic Stem Cells ,GOT2 ,Article ,Transaminase ,Cell biology ,Mice ,Haematopoiesis ,medicine.anatomical_structure ,Genetics ,medicine ,Animals ,Molecular Medicine ,Asparagine ,Stem cell ,Progenitor cell ,hormones, hormone substitutes, and hormone antagonists ,Cell Proliferation - Abstract
The electron transport chain promotes aspartate synthesis, which is required for cancer cell proliferation. However, it is unclear whether aspartate is limiting in normal stem cells. We found that mouse hematopoietic stem cells (HSCs) depend entirely on cell-autonomous aspartate synthesis, which increases upon HSC activation. Over-expression of the glutamate/aspartate transporter, Glast, or deletion of glutamic-oxaloacetic transaminase 1 (Got1) each increased aspartate levels in hematopoietic stem/progenitor cells and increased the function of HSCs but not colony-forming progenitors. Conversely, deletion of glutamic-oxaloacetic transaminase 2 (Got2) reduced aspartate levels and the function of HSCs but not colony-forming progenitors. Deletion of Got1 and Got2 eliminated HSCs. Isotope tracing showed aspartate was used to synthesize asparagine and purines. Both contributed to increased HSC function as deletion of asparagine synthetase or treatment with 6-mercaptopurine attenuated the increased function of GLAST over-expressing HSCs. HSC function is thus limited by aspartate, purine, and asparagine availability during hematopoietic regeneration.
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- 2021
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39. Ischemic Neuroprotectant PKCε Restores Mitochondrial Glutamate Oxaloacetate Transaminase in the Neuronal NADH Shuttle after Ischemic Injury
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Samuel D. Stegelmann, Kunjan R. Dave, Jing Xu, Miguel A. Perez-Pinzon, Nathalie Khoury, Charles W. Jackson, and Iris Escobar
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0301 basic medicine ,Male ,Primary Cell Culture ,Malates ,Malate-aspartate shuttle ,Oxidative phosphorylation ,Protein Kinase C-epsilon ,Mitochondrion ,GOT2 ,Article ,Brain Ischemia ,Rats, Sprague-Dawley ,03 medical and health sciences ,0302 clinical medicine ,Medicine ,Animals ,Glycolysis ,Phosphorylation ,Inner mitochondrial membrane ,Aspartate Aminotransferase, Mitochondrial ,Neurons ,business.industry ,General Neuroscience ,NAD ,Cell biology ,030104 developmental biology ,Neurology (clinical) ,NAD+ kinase ,Cardiology and Cardiovascular Medicine ,business ,030217 neurology & neurosurgery - Abstract
The preservation of mitochondrial function is a major protective strategy for cerebral ischemic injuries. Previously our laboratory demonstrated that protein kinase C epsilon (PKCε) promotes the synthesis of mitochondrial Nicotinamide adenine dinucleotide (NAD(+)). NAD(+) along with its reducing equivalent, NADH, is an essential co-factor needed for energy production from glycolysis and oxidative phosphorylation. Yet, NAD(+)/NADH are impermeable to the inner mitochondrial membrane and their import into the mitochondria requires the activity of specific shuttles. The most important neuronal NAD(+)/NADH shuttle is the malate-aspartate shuttle (MAS). The MAS has been implicated in synaptic function and is potentially dysregulated during cerebral ischemia. The aim of this study was to determine if metabolic changes induced by PKCε preconditioning involved regulation of the MAS. Using primary neuronal cultures, we observed that the activation of PKCε enhanced mitochondrial respiration and glycolysis in vitro. Conversely, inhibition of the MAS resulted in decreased oxidative phosphorylation and glycolytic capacity. We further demonstrated that activation of PKCε increased the phosphorylation of key components of the MAS in rat brain synaptosomal fractions. Additionally, PKCε increased the enzyme activity of Glutamic oxaloacetic transaminase 2 (GOT2), an effect that was dependent on the import of PKCε into the mitochondria and phosphorylation of GOT2. Furthermore, PKCε activation was able to rescue against decreased GOT2 activity induced by ischemia. These findings reveal novel protective targets and mechanisms against ischemic injury, which involves PKCε-mediated phosphorylation and activation of GOT2 in the MAS.
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- 2019
40. Analysis of miRNA-mRNA network reveals miR-140-5p as a suppressor of breast cancer glycolysis via targeting GLUT1
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Yunjie He, Jianhua Zhao, Wei Zhang, Jian Zhang, Xiu Chen, Fei Deng, Dan-Dan Wang, Jinhai Tang, Li Ding, Jun-Chen Hou, Zuomin Zhou, Shanliang Zhong, and Shujie Zhao
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0301 basic medicine ,Cancer Research ,Down-Regulation ,Breast Neoplasms ,Biology ,GOT2 ,law.invention ,03 medical and health sciences ,0302 clinical medicine ,Breast cancer ,law ,Cell Line, Tumor ,microRNA ,Genetics ,medicine ,Biomarkers, Tumor ,Humans ,RNA, Messenger ,Glyceraldehyde 3-phosphate dehydrogenase ,Cell Proliferation ,Glucose Transporter Type 1 ,medicine.disease ,Prognosis ,MicroRNAs ,030104 developmental biology ,Anaerobic glycolysis ,030220 oncology & carcinogenesis ,PFKP ,Cancer research ,biology.protein ,Suppressor ,Female ,Breast carcinoma ,Glycolysis - Abstract
Aim: Aerobic glycolysis is characteristic of breast cancer. Comprehensive expression profiles of key proteins, their prognosis and detailed relationships between miRNAs and mRNAs remain unclear. Materials & methods: Oncomine database, Kaplan–Meier overall survival and miRNA–mRNA network analysis were performed. A key miRNA was identified and explored in vitro and in vivo. Results & conclusion: Eleven key glycolytic proteins were found with higher expression and poor prognosis: GLUT1, SLC2A5, HK1, PFKP, ALDOA, TPI1, GAPDH, PGK1, ENO1, GOT1 and GOT2. Seven miRNAs were predicted targeting 11 key glycolytic proteins: miR-140-5p, miR-3064-5p, miR-152-3p, miR-449b-5p, miR-449a, miR-194-5p and miR-34a-5p. Among them, miR-140-5p was found to be downregulated in breast cancer and directly targeted GLUT1, resulting in an antiglycolytic and antiproliferative effect.
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- 2019
41. Nutrition and Diabetes
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Richard F. Helm, Mark A. Cline, W. Keith Ray, Paul B. Siegel, Jiaqing Yi, Lingbin Liu, Lucas T. Vu, Elizabeth R. Gilbert, and Animal and Poultry Sciences
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0301 basic medicine ,medicine.medical_specialty ,Proteome ,Endocrinology, Diabetes and Metabolism ,media_common.quotation_subject ,Hypothalamus ,Appetite ,030209 endocrinology & metabolism ,Oxidative phosphorylation ,Lipocalin ,GOT2 ,Article ,03 medical and health sciences ,Eating ,0302 clinical medicine ,Species Specificity ,Tandem Mass Spectrometry ,Internal medicine ,Internal Medicine ,Medicine ,Animals ,Obesity ,lcsh:RC620-627 ,media_common ,030109 nutrition & dietetics ,biology ,business.industry ,Succinate dehydrogenase ,Body Weight ,Fasting ,Sialic acid synthase ,Anorexia ,Citric acid cycle ,lcsh:Nutritional diseases. Deficiency diseases ,Endocrinology ,Fumarase ,biology.protein ,business ,Chickens ,Chromatography, Liquid - Abstract
Background: The hypothalamus is the ultimate modulator of appetite and energy balance and therefore sensitive to changes in nutritional state. Chicks from lines selected for low (LWS) and high (HWS) body weight are hypophagic and compulsive eaters, respectively, and differ in their propensity to become obese and in their hypothalamic mRNA response to fasting. Methods: As fasting-induced changes in hypothalamic proteins are unknown, we investigated the hypothalamic proteomes of 5-day old LWS and HWS chicks in the fed and fasted states using a label-free liquid chromatographytandem mass spectrometry (LC-MS/MS) approach. Results: A total of 744 proteins were identified in the chicken hypothalamus, and 268 differentially abundant proteins were identified among four pairwise comparisons. Ninety-five proteins were associated with the response to fasting in HWS chicks, and 23 proteins were associated with the response to fasting in LWS chicks. Fasting-responsive proteins in HWS chicks were significantly enriched in ATP metabolic processes, glyoxylate/dicarboxylate metabolism, and ribosome function. There was no enrichment for any pathways in LWS chicks in response to fasting. In the fasted and fed states, 159 and 119 proteins differed between HWS and LWS, respectively. Oxidative phosphorylation, citric acid cycle, and carbon metabolism were the main pathways associated with differences between the two lines of chicks. Enzymes associated with metabolic pathways differed between HWS and LWS in both nutritional states, including fumarase, aspartate aminotransferase, mitochondrial GOT2, 3-hydroxyisobutyrate dehydrogenase, chondrogenesis associated lipocalin, sialic acid synthase, arylamine N-acetyltransferase, pineal gland isozyme NAT-3, and succinate dehydrogenase [ubiquinone] flavoprotein subunit, mitochondrial. Conclusions: These results provide insights into the hypothalamic metabolic pathways that are affected by nutritional status and the regulation of appetite and eating behavior. This research was supported by grant funding from Virginia’s Commonwealth Health Research Board and in part, by the Virginia Agricultural Experiment Station and the Hatch Program of the National Institute of Food and Agriculture, U.S. Department of Agriculture. Mass spectrometry resources used in this work aremaintained in part through funding by the Fralin Life Science Institute, the Agricultural Experiment Station Hatch Program, and the McIntire-Stennis Program at Virginia Tech.
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- 2019
42. Vitamin B6 Addiction in Acute Myeloid Leukemia
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Lingbo Zhang, Sara Violante, John P. Morris, Scott E. Millman, Xiang Li, Allison Mayle, Hardik Shah, Scott W. Lowe, Yu-Jui Ho, Evangelia Loizou, Chi-Chao Chen, Weige Qin, Justin R. Cross, Cynthia Chen, Hui Liu, and Bo Li
- Subjects
0301 basic medicine ,Cancer Research ,Biology ,GOT2 ,Article ,GTP Phosphohydrolases ,03 medical and health sciences ,chemistry.chemical_compound ,Mice ,0302 clinical medicine ,hemic and lymphatic diseases ,Cell Line, Tumor ,Polyamines ,Animals ,Humans ,Kinase activity ,Pyridoxal phosphate ,RNA, Small Interfering ,Cell Proliferation ,Monomeric GTP-Binding Proteins ,Cell growth ,Gene Expression Regulation, Leukemic ,Phosphotransferases ,Pyridoxine ,Myeloid leukemia ,Membrane Proteins ,Cell Biology ,Pyridoxal kinase ,Vitamin B 6 ,Leukemia, Myeloid, Acute ,Phosphotransferases (Alcohol Group Acceptor) ,030104 developmental biology ,Oncology ,chemistry ,030220 oncology & carcinogenesis ,Pyridoxal Phosphate ,Cancer cell ,Cancer research ,CRISPR-Cas Systems ,Intracellular - Abstract
Summary Cancer cells rely on altered metabolism to support abnormal proliferation. We performed a CRISPR/Cas9 functional genomic screen targeting metabolic enzymes and identified PDXK—an enzyme that produces pyridoxal phosphate (PLP) from vitamin B6—as an acute myeloid leukemia (AML)-selective dependency. PDXK kinase activity is required for PLP production and AML cell proliferation, and pharmacological blockade of the vitamin B6 pathway at both PDXK and PLP levels recapitulated PDXK disruption effects. PDXK disruption reduced intracellular concentrations of key metabolites needed for cell division. Furthermore, disruption of PLP-dependent enzymes ODC1 or GOT2 selectively inhibited AML cell proliferation and their downstream products partially rescued PDXK disruption induced proliferation blockage. Our work identifies the vitamin B6 pathway as a pharmacologically actionable dependency in AML.
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- 2019
43. HIF1α Suppresses Tumor Cell Proliferation through Inhibition of Aspartate Biosynthesis
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Sarah-Maria Fendt, Mar Torres-Capelli, Qilong Oscar Yang Li, Marta Ortega Muelas, Enrique Fraga, Antonio Martínez-Ruiz, Antonio Bouthelier, Daniel Tello, Ainara Elorza, Florinda Meléndez-Rodríguez, Pablo Hernansanz-Agustín, Olga Roche, Till Acker, Nuray Böğürcü-Seidel, Claudia Mesa-Ciller, Elia Escasany, Julián Aragonés, Guillermo Turiel, Andres A. Urrutia, Katrien De Bock, José M. Giménez-Bachs, Belén Pérez, Ricardo Sánchez Prieto, Doriane Lorendeau, Antonio S. Salinas-Sánchez, Gianmarco Rinaldi, Esther Fuertes, UAM. Departamento de Medicina, Instituto de Investigaciones Biomédicas 'Alberto Sols' (IIBM), Instituto de Investigación del Hospital de La Princesa (IP), Agencia Estatal de Investigación (España), Ministerio de Economía y Competitividad (España), Comunidad de Madrid, Fundació La Marató de TV3, European Commission, Research Foundation - Flanders, Universidad de Castilla La Mancha, Ministerio de Educación y Ciencia (España), Ministerio de Ciencia, Innovación y Universidades (España), and Fundación Leticia Castillejo
- Subjects
0301 basic medicine ,Male ,endocrine system diseases ,Glutamine ,Proliferation ,Hif1α ,CITRATE ,0302 clinical medicine ,Aspartate biosynthesis ,Neoplasms ,HIF1α ,Cancer ,Aged, 80 and over ,REDUCTIVE CARBOXYLATION ,Middle Aged ,Renal cell carcinoma ,Kidney Neoplasms ,HIF-ALPHA ,Von Hippel-Lindau Tumor Suppressor Protein ,GROWTH ,Female ,aspartate biosynthesis ,GOT2 ,Life Sciences & Biomedicine ,Oxidation-Reduction ,GOT1 ,Aspartate Aminotransferase, Cytoplasmic ,hormones, hormone substitutes, and hormone antagonists ,FLUX ,Adult ,cancer ,proliferation ,oxygen ,renal cell carcinoma ,Medicina ,Tumor cells ,GLUTAMINE-METABOLISM ,General Biochemistry, Genetics and Molecular Biology ,Marie curie ,Mitochondrial Proteins ,03 medical and health sciences ,Political science ,Cell Line, Tumor ,Curie ,Humans ,Carcinoma, Renal Cell ,Aged ,Aspartate Aminotransferase, Mitochondrial ,Cell Proliferation ,Aspartic Acid ,Science & Technology ,Tumor Suppressor Proteins ,nutritional and metabolic diseases ,Cell Biology ,Hypoxia-Inducible Factor 1, alpha Subunit ,Molecular biology ,Oxygen ,030104 developmental biology ,030217 neurology & neurosurgery - Abstract
Cellular aspartate drives cancer cell proliferation, but signaling pathways that rewire aspartate biosynthesis to control cell growth remain largely unknown. Hypoxia-inducible factor-1α (HIF1α) can suppress tumor cell proliferation. Here, we discovered that HIF1α acts as a direct repressor of aspartate biosynthesis involving the suppression of several key aspartate-producing proteins, including cytosolic glutamic-oxaloacetic transaminase-1 (GOT1) and mitochondrial GOT2. Accordingly, HIF1α suppresses aspartate production from both glutamine oxidation as well as the glutamine reductive pathway. Strikingly, the addition of aspartate to the culture medium is sufficient to relieve HIF1α-dependent repression of tumor cell proliferation. Furthermore, these key aspartate-producing players are specifically repressed in VHL-deficient human renal carcinomas, a paradigmatic tumor type in which HIF1α acts as a tumor suppressor, highlighting the in vivo relevance of these findings. In conclusion, we show that HIF1α inhibits cytosolic and mitochondrial aspartate biosynthesis and that this mechanism is the molecular basis for HIF1α tumor suppressor activity., Cell Reports, 26 (9), ISSN:2666-3864, ISSN:2211-1247
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- 2019
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44. Expression of GOT2 Is Epigenetically Regulated by DNA Methylation and Correlates with Immune Infiltrates in Clear-Cell Renal Cell Carcinoma.
- Author
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Ferreira WAS and de Oliveira EHC
- Abstract
Clear cell renal cell carcinoma (KIRC) is the most common and highly malignant pathological type of kidney cancer, characterized by a profound metabolism dysregulation. As part of aspartate biosynthesis, mitochondrial GOT2 (glutamic-oxaloacetic transaminase 2) is essential for regulating cellular energy production and biosynthesis, linking multiple pathways. Nevertheless, the expression profile and prognostic significance of GOT2 in KIRC remain unclear. This study comprehensively analyzed the transcriptional levels, epigenetic regulation, correlation with immune infiltration, and prognosis of GOT2 in KIRC using rigorous bioinformatics analysis. We discovered that the expression levels of both mRNA and protein of GOT2 were remarkably decreased in KIRC tissues in comparison with normal tissues and were also significantly related to the clinical features and prognosis of KIRC. Remarkably, low GOT2 expression was positively associated with poorer overall survival (OS) and disease-free survival (DFS). Further analysis revealed that GOT2 downregulation is driven by DNA methylation in the promoter-related CpG islands. Finally, we also shed light on the influence of GOT2 expression in immune cell infiltration, suggesting that GOT2 may be a potential prognostic marker and therapeutic target for KIRC patients.
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- 2022
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45. Effect of hypoxia on the expression of nuclear genes encoding mitochondrial proteins in U87 glioma cells
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Dmytro O. Minchenko, Oleksandr H. Minchenko, O O Ratushna, O O Riabovol, and D O Tsymbal
- Subjects
SDHB ,Protein Serine-Threonine Kinases ,Mitochondrion ,Biochemistry ,GOT2 ,Mitochondrial Proteins ,lcsh:Biochemistry ,Malate Dehydrogenase ,Cell Line, Tumor ,Endoribonucleases ,Gene expression ,Humans ,lcsh:QD415-436 ,Aspartate Aminotransferases ,Cell Proliferation ,Cell Nucleus ,Regulation of gene expression ,Gene knockdown ,Chemistry ,Endoplasmic reticulum ,Nuclear Proteins ,Endoplasmic Reticulum Stress ,Molecular biology ,Cell Hypoxia ,Isocitrate Dehydrogenase ,Mitochondria ,Gene Expression Regulation, Neoplastic ,Succinate Dehydrogenase ,Protein Transport ,SDHD ,Neuroglia ,Signal Transduction - Abstract
We have studied the effect of hypoxia on the expression of nuclear genes encoding mitochondrial proteins in U87 glioma cells under the inhibition of IRE1 (inositol requiring enzyme-1), which controls cell proliferation and tumor growth as a central mediator of endoplasmic reticulum stress. It was shown that hypoxia down-regulated gene expression of malate dehydrogenase 2 (MDH2), malic enzyme 2 (ME2), mitochondrial aspartate aminotransferase (GOT2), and subunit B of succinate dehydrogenase (SDHB) in control (transfected by empty vector) glioma cells in a gene specific manner. At the same time, the expression level of mitochondrial NADP+-dependent isocitrate dehydrogenase 2 (IDH2) and subunit D of succinate dehydrogenase (SDHD) genes in these cells does not significantly change in hypoxic conditions. It was also shown that the inhibition of ІRE1 signaling enzyme function in U87 glioma cells decreases the effect of hypoxia on the expression of ME2, GOT2, and SDHB genes and introduces the sensitivity of IDH2 gene to hypoxia. Furthermore, the expression of all studied genes depends on IRE1-mediated endoplasmic reticulum stress signaling in gene specific manner, because ІRE1 knockdown significantly decreases their expression in normoxic conditions, except for IDH2 gene, which expression level is strongly up-regulated. Therefore, changes in the expression level of nuclear genes encoding ME2, MDH2, IDH2, SDHB, SDHD, and GOT2 proteins possibly reflect metabolic reprogramming of mitochondria by hypoxia and IRE1-mediated endoplasmic reticulum stress signaling and correlate with suppression of glioma cell proliferation under inhibition of the IRE1 enzyme function.
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- 2016
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46. LncRNA Seduction of GOT2 Goes Viral
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Howard Y. Chang and Y. Grace Chen
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0301 basic medicine ,viruses ,Immunology ,RNA ,Biology ,Viral infection ,GOT2 ,Cell biology ,03 medical and health sciences ,030104 developmental biology ,Infectious Diseases ,Viral replication ,Metabolic enzymes ,microRNA ,Immunology and Allergy ,Function (biology) - Abstract
Mechanisms of viral infection are active areas of investigation. In a recent issue of Science, Wang et al. (2017) reveal an additional function of a host-encoded long non-coding RNA (lncRNA) in regulating viral expression by binding a host metabolic enzyme to enhance its catalytic activity.
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- 2017
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47. Glutamine Metabolism Controls Chondrocyte Identity and Function
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Geert Carmeliet, Karen Moermans, Ingrid Stockmans, Sarah-Maria Fendt, Peter Carmeliet, Shauni Loopmans, Gianmarco Rinaldi, Bernard Thienpont, and Steve Stegen
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Male ,Glutamine ,SOX9 ,Biology ,survival ,GOT2 ,General Biochemistry, Genetics and Molecular Biology ,Chondrocyte ,Mice ,03 medical and health sciences ,chemistry.chemical_compound ,Chondrocytes ,0302 clinical medicine ,Glutaminase ,Biosynthesis ,glutamine metabolism ,medicine ,Animals ,Molecular Biology ,Transcription factor ,Cells, Cultured ,GLS1 ,Cell Proliferation ,030304 developmental biology ,0303 health sciences ,redox homeostasis ,histone acetylation ,Cell Differentiation ,SOX9 Transcription Factor ,Cell Biology ,Chondrogenesis ,GLUD1 ,Cell biology ,endochondral ossification ,medicine.anatomical_structure ,chemistry ,chondrocyte ,Female ,biosynthesis ,030217 neurology & neurosurgery ,Developmental Biology - Abstract
Correct functioning of chondrocytes is crucial for long bone growth and fracture repair. These cells are highly anabolic but survive and function in an avascular environment, implying specific metabolic requirements that are, however, poorly characterized. Here, we show that chondrocyte identity and function are closely linked with glutamine metabolism in a feedforward process. The master chondrogenic transcription factor SOX9 stimulates glutamine metabolism by increasing glutamine consumption and levels of glutaminase 1 (GLS1), a rate-controlling enzyme in this pathway. Consecutively, GLS1 action is critical for chondrocyte properties and function via a tripartite mechanism. First, glutamine controls chondrogenic gene expression epigenetically through glutamate dehydrogenase-dependent acetyl-CoA synthesis, necessary for histone acetylation. Second, transaminase-mediated aspartate synthesis supports chondrocyte proliferation and matrix synthesis. Third, glutamine-derived glutathione synthesis avoids harmful reactive oxygen species accumulation and allows chondrocyte survival in the avascular growth plate. Collectively, our study identifies glutamine as a metabolic regulator of cartilage fitness during bone development. ispartof: DEVELOPMENTAL CELL vol:53 issue:5 pages:530-+ ispartof: location:United States status: published
- Published
- 2020
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48. Mitochondrial glutamine metabolism via GOT2 supports pancreatic cancer growth through senescence inhibition
- Author
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Sunsook Hwang, Jeong-Hwa Lee, Sung Bin Seo, Seungyeon Yang, Seung Min Jeong, and Minjoong Kim
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0301 basic medicine ,Senescence ,Cancer Research ,Glutamine ,Immunology ,Biology ,GOT2 ,Article ,03 medical and health sciences ,Cellular and Molecular Neuroscience ,Cell Line, Tumor ,Humans ,Aspartate Aminotransferases ,lcsh:QH573-671 ,Cellular Senescence ,Cell Proliferation ,Gene knockdown ,lcsh:Cytology ,Kinase ,HEK 293 cells ,Cell Biology ,Mitochondria ,Cell biology ,Pancreatic Neoplasms ,HEK293 Cells ,030104 developmental biology ,Cell culture ,Cancer cell ,Carcinoma, Pancreatic Ductal - Abstract
Cellular senescence, which leads to a cell cycle arrest of damaged or dysfunctional cells, is an important mechanism to restrain the malignant progression of cancer cells. Because metabolic changes underlie many cell-fate decisions, it has been suggested that cell metabolism might play key roles in senescence pathways. Here, we show that mitochondrial glutamine metabolism regulates senescence in human pancreatic ductal adenocarcinoma (PDAC) cells. Glutamine deprivation or inhibition of mitochondrial aspartate transaminase (GOT2) results in a profound induction of senescence and a suppression of PDAC growth. Glutamine carbon flow through GOT2 is required to create NADPH and to maintain the cellular redox state. We found that elevated reactive oxygen species levels by GOT2 knockdown lead to the cyclin-dependent kinase inhibitor p27-mediated senescence. Importantly, PDAC cells exhibit distinct dependence on this pathway, whereas knockdown of GOT2 did not induce senescence in non-transformed cells. The essentiality of GOT2 in senescence regulation of PDAC, which is dispensable in their normal counterparts, may have profound implications for the development of strategies to treat these refractory cancers.
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- 2018
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49. Circular RNA circ_0003028 contributes to tumorigenesis by regulating GOT2 via miR-1298-5p in non-small cell lung cancer.
- Author
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Guan H, Sun C, Gu Y, Li J, Ji J, and Zhu Y
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- Animals, Apoptosis genetics, Carcinogenesis genetics, Cell Line, Tumor, Cell Proliferation genetics, Gene Expression Regulation, Neoplastic genetics, Humans, Lung metabolism, Lung pathology, Male, Mice, Mice, Nude, Aspartate Aminotransferases genetics, Aspartate Aminotransferases metabolism, Carcinoma, Non-Small-Cell Lung genetics, Carcinoma, Non-Small-Cell Lung metabolism, Carcinoma, Non-Small-Cell Lung pathology, Lung Neoplasms genetics, Lung Neoplasms metabolism, Lung Neoplasms pathology, MicroRNAs genetics, MicroRNAs metabolism, RNA, Circular genetics, RNA, Circular metabolism
- Abstract
Non-small cell lung cancer (NSCLC) is a common malignant tumor, with high morbidity and mortality. Circular RNA (circRNA) circ_0003028 was reported to be upregulated in NSCLC. This study is designed to explore the role and mechanism of circ_0003028 on NSCLC progression. In this work, circ_0003028, microRNA-1298-5p (miR-1298-5p), and glutamic oxaloacetic transaminase 2 (GOT2) level were detected by real-time quantitative polymerase chain reaction (RT-qPCR). The localization of circ_0003028 was analyzed by subcellular fractionation assay. Cell proliferation, colony number, cell cycle progression, apoptosis, migration, invasion, and angiogenesis were measured by Cell Counting Kit-8 (CCK-8), colony formation, flow cytometry, transwell, and tube formation assays. Protein levels of Beclin1, light chain 3 (LC3)-II/LC3-I, GOT2, proliferating cell nuclear antigen (PCNA) were examined by western blot assay. The binding relationship between miR-1298-5p and circ_0003028 or GOT2 was predicted by circular RNA Interactome or starbase and then verified by dual-luciferase reporter, RNA Immunoprecipitation (RIP), and RNA pull-down assays. The biological role of circ_0003028 on NSCLC tumor growth was examined by the xenograft tumor model in vivo . We reported that circ_0003028 and GOT2 were upregulated, and miR-1298-5p was decreased in NSCLC tissues and cells. Moreover, circ_0003028 knockdown curbed cell proliferative ability, migration, invasion, angiogenesis, and facilitate apoptosis and autophagy in NSCLC cells in vitro . Mechanical analysis discovered that circ_0003028 regulated GOT2 expression by sponging miR-1298-5p. Circ_0003028 silencing hindered the cell growth of NSCLC in vivo . Taken together, circ_0003028 knockdown could suppress NSCLC progression partly by regulating the miR-1298-5p/GOT2 axis, providing an underlying therapeutic target for NSCLC.
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- 2021
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50. Expression, purification and preliminary crystallographic studies of human glutamate oxaloacetate transaminase 1 (GOT1)
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Yong Zhou, Xiuping Jiang, and Haiyang Chang
- Subjects
chemistry.chemical_classification ,biology ,Stereochemistry ,Periplasmic space ,Crystallography, X-Ray ,GOT2 ,Recombinant Proteins ,Amino acid ,Glutamine ,chemistry.chemical_compound ,Crystallography ,Enzyme ,chemistry ,Affinity chromatography ,Enzyme Stability ,Escherichia coli ,biology.protein ,Humans ,Citrate synthase ,Pyridoxal ,Aspartate Aminotransferase, Cytoplasmic ,Biotechnology - Abstract
Glutamate oxaloacetate transaminase (GOT) catalyzes the reversible reaction of l -aspartate and α-ketoglutarate into oxaloacetate and l -glutamate and plays a key role in carbon and nitrogen metabolism in all organisms. In human tissues, GOTs are pyridoxal 5′-phosphate-dependent (PLP) enzymes which exist in cytoplasm and mitochondrial forms, GOT1 and GOT2, respectively. GOT1 expression correlates with the growth of several tumors because cancer cells can utilize the amino acid glutamine to fuel anabolic processes, and therefore, GOT1 represents a new therapeutic target in cancer. In this work, human GOT1 was expressed in Escherichia coli periplasmic space, and purified by a combination of His-tag immobilized metal-ion affinity chromatography and anion exchange chromatography. Optimal activity of the enzyme occurred at a temperature of 37 °C and a pH of 7.5. Cations such as Na + , K + and Mg 2+ slightly inhibited the activity of recombinant human GOT1, while Zn 2+ , Mn 2+ , Cu 2+ , Ni 2+ , Co 2+ and Ca 2+ had stronger inhibitory effects. Crystals of human GOT1 were grown using the hanging-drop vapor diffusion method at 4 °C with 0.1 M Bis–Tris pH 6.0% and 21% (w/v) PEG 3350. The crystals diffracted to 2.99 A resolution and belonged to space group P 4 3 2 1 2 with the unit cell parameters a = b = 93.4, c = 107.4 A, α = β = γ = 90°.
- Published
- 2015
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