• BMB Reports
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• v.32 no.4
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• pp.385-392
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• 1999

The $NAD^+$-specific activity of a dual coenzyme-specific isocitrate dehydrogenase (IDH; EC 1.1.1.41) from the primitive fungus Pythium ultimum was investigated to elucidate the regulatory factors that may influence the intracellular distribution of carbon and the availability of intermediates, e.g. citrate, for fatty acid synthesis. Inhibition of $NAD^+$-IDH activity by diphospho- and triphosphonucleotides (ATP, ADP, and GTP) reflected the sensitivity of this enzyme to cellular energy charge even though monophosphonucleotides (AMP and GMP) had little effect on activity. NADPH, but not NADH, substantially inhibited $NAD^+$-IDH activity, showing noncompetitive inhibition with isocitrate. Oxalacetate and ${\alpha}$-ketoglutarate showed competitive inhibition with isocitrate, while citrate and cis-aconitate showed mixed-noncompetitive inhibition with isocitrate. Inhibition by these substances ranged from 29 to 46% at 10 mM. The inhibitory effect of oxalacetate was increased synergistically by glyoxylate, which alone caused 31% uncompetitive inhibition at 10 mM, and a mixture of the two substances at 1 mM each showed 98% inhibition of $NAD^+$-IDH activity. The regulation of $NAD^+$-IDH in Pythium ultimum seems to be a complex process involving mitochondrial metabolites. The addition of glyoxylate (3 mM) and oxalacetate (3 mM) to the culture medium resulted in the production of 49% more lipid by P. ultimum.

• The Korean Journal of Ecology
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• v.14 no.1
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• pp.75-85
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• 1991

Changes in the activities of isocitrate dehydrogenase (IDH) and glutamate dehydrogenase (GDH) and changes in free amino acids in the cytoplasm of Saccharomyces cerevisiae have been studied under heat shock condition. Heat shock conditions led to a significant decrease of NAD-IDH and NAD-GDH, It was shown appeared that the meaningful patterns of increase of NADP-IDH and NADP-GDH. It suggested that heat shock in yeast leads to a splitting of the TCA cycle and that glutamate synthesis takes place through the coupling of the NADP-linked isocirate and glutamate dehydrogenase. It was shown that about 14% of total free amino acids of yeast cells was decreased by heat shock. Especially heat shock condition resulted in the marked decreases of serine family amino acids such as serine, glycine and cysteine, and in the considerable increases of the rates of methionine, alanine, glutamin.

• BMB Reports
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• v.48 no.5
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• pp.266-270
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• 2015

Over the last decade, comprehensive genome-wide sequencing studies have enabled us to find out unexpected genetic alterations of metabolism in cancer. An example is the identification of arginine missense mutations of isocitrate dehydrogenases-1 and -2 (IDH1/2) in glioma, acute myeloid leukemia (AML), chondrosarcomas, and cholangiocarcinoma. These alterations are closely associated with the production of a new stereospecific metabolite, (R)-2-hydroxyglutarate (R-2HG). A large number of follow-up studies have been performed to address the molecular mechanisms of IDH1/2 mutations underlying how these events contribute to malignant transformation. In the meanwhile, the development of selective mutant IDH1/2 chemical inhibitors is being actively pursued in the scientific community and pharmaceutical industry. The present review article briefly discusses the important findings that highlight the molecular mechanisms of IDH1/2 mutations in cancer and provides a current status for development of selective mutant IDH1/2 chemical inhibitors. [BMB Reports 2015; 48(5): 266-270]

• Korean Journal of Radiology
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• v.24 no.12
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• pp.1303-1305
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• 2023

• Investigative Magnetic Resonance Imaging
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• v.19 no.4
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• pp.218-223
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• 2015

Purpose: To investigate whether volumetric analysis based on T2WI and contrast-enhanced (CE) T1WI can distinguish between isocitrate dehydrogenase-1 mutation-positive ($IDH1^P$) and -negative ($IDH1^N$) glioblastomas (GBMs). Materials and Methods: We retrospectively enrolled 109 patients with histopathologically proven GBMs after surgery or stereotactic biopsy and preoperative MR imaging. We measured the whole-tumor volume in each patient using a semiautomatic segmentation method based on both T2WI and CE T1WI. We compared the tumor volumes between $IDH1^P$ (n = 12) and $IDH1^N$ (n = 97) GBMs using an unpaired t-test. In addition, we performed receiver operating characteristic (ROC) analysis for the differentiation of $IDH1^P$ and $IDH1^N$ GBMs using the tumor volumes based on T2WI and CE T1WI. Results: The mean tumor volume based on T2WI was larger for $IDH1^P$ GBMs than $IDH1^N$ GBMs ($108.8{\pm}68.1$ and $59.3{\pm}37.3mm^3$, respectively, P = 0.0002). In addition, $IDH1^P$ GBMs had a larger tumor volume on CE T1WI than did $IDH1^N$ tumors ($49.00{\pm}40.14$ and $22.53{\pm}17.51mm^3$, respectively, P < 0.0001). ROC analysis revealed that the tumor volume based on T2WI could distinguish $IDH1^P$ from $IDH1^N$ with a cutoff value of 90.25 (P < 0.05): 7 of 12 $IDH1^P$ (58.3%) and 79 of 97 $IDH1^N$ (81.4%). Conclusion: Volumetric analysis of T2WI and CE T1WI could enable $IDH1^P$ GBMs to be distinguished from $IDH1^N$ GBMs. We assumed that secondary GBMs with $IDH1^P$ underwent stepwise progression and were more infiltrative than those with $IDH1^N$, which might have resulted in the differences in tumor volume.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.14
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• pp.5875-5881
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• 2015

Cholangiocarcinoma (CCA) is a rare but highly fatal cancer for which the molecular mechanisms and diagnostic markers are obscure. We therefore investigated the kinetic expression of isocitrate dehydrogenase-1 (IDH1), isocitrate dehydrogenase-2 (IDH2) and homogentisate 1,2-dioxygenase (HGD) during the tumorigenesis of O. viverrini infection-associated CCA in an animal model, and confirmed down-regulation of expression in human cases of opisthorchiasis-associated CCA through real time PCR. Kinetic expression of HGD, IDH1 and IDH2 in the animal model of O. viverrini infection-induced CCA was correlated with human CCA cases. In the animal model, expression of HGD was decreased at all time points (p<0.01) and expression of both IDH1 and IDH2 was decreased in the CCA group. In human cases, expression of HGD, IDH1 and IDH2 was decreased more than 2 fold in 55 cases (70.5%), 25 cases (32.1%) and 24 cases (30.8%) respectively. The present study suggests that reduction of HGD, IDH1 and IDH2 may be involve in cholangiocarcinoma genesis and may be useful for molecular diagnosis.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.8
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• pp.3355-3360
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• 2015

Background: Zinc transporters have been considered as essential regulators in many cancers; however, their mechanisms remain unknown, especially in gliomas. Isocitrate dehydrogenase 1(IDH1) mutation is crucial to glioma. This study aimed to investigate whether zinc transporters are correlated with glioma grade and IDH1 mutation status. Materials and Methods: IDH1 mutation status and mRNA expression of four zinc transporters (ZIP4, ZIP9, ZIP11, and ZnT9) were determined by subjecting a panel of 74 glioma tissue samples to quantitative real-time PCR and pyrosequencing. The correlations between the expression levels of these zinc transporter genes and the grade of glioma, as well as IDH1 mutation status, were investigated. Results: Among the four zinc transporter genes, high ZIP4 expression and low ZIP11 expression were significantly associated with higher grade (grades III and IV) tumors compared with lower grade (grades I and II) counterparts (p<0.0001). However, only ZIP11 exhibited weak correlation with IDH1 mutation status (p=0.045). Samples with mutations in IDH1 displayed higher ZIP11 expression than those without IDH1 mutations. Conclusions: This finding indicated that zinc transporters may interact with IDH1 mutation by direct modulation or action in some shared pathways or genes to promote the development of glioma. Zinc transporters may play an important role in glioma. ZIP4 and ZIP11 are promising molecular diagnostic markers and novel therapeutic targets. Nevertheless, the detailed biological function of zinc transporters and the mechanism of the potential interaction between ZIP11 and IDH1 mutation in gliomagenesis should be further investigated.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.1
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• pp.427-432
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• 2014

Isocitrate dehydrogenase (IDH) is of great importance in cell metabolism and energy conversion. IDH mutation in glioma cells is reported to be associated with an increased overall survival. However, effects biological behavior of therapy of gliomas are unclear. Here, we investigated the influence of wild-type and mutated IDH genes on glioma cell biological behavior and response to chemotherapy. Relevant mechanisms were further explored. We designed our study on the background of the IDHR132H mutation. Stable cell lines were constructed by transfection. The CCK-8 method was used to assess cell proliferation, flow cytometry for the cell cycle and cell apoptosis, and the transwell method for cell invasion. Nude mouse models were employed to determine tumorigenesis and sensitivity to chemotherapy. Western blotting was used to detect relevant protein expression levels. We found that overexpression of wild IDH1 gene did not cause changes in the cell cycle, apoptosis and invasion ability. However, it resulted in chemotherapy resistance to a high dose of temozolomide (TMZ) in vivo and in vitro. The IDH1 mutation caused cell cycle arrest in G1 stage and a reduction of proliferation and invasion ability, while raising sensitivity to chemotherapy. This may provide an explanation for the better prognosis of IDH1 mutated glioma patients and the relative worse prognosis of their wild-type IDH1 counterparts. We also expect IDH1 mutations may be optimized as new targets to improve the prognosis of glioma patients.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.1
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• pp.83-88
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• 1994

For the purpose of genetic stock indentification of three species of salmonid fishs and their hybrid, lactate dehydrogenase(LDH), malate dehydrogenase(MDH), isocitrate dehydrogenase(IDH), a-gylycerophosphate dehydrogenase(a-GPDH), malic enzyme(ME), 6-phospho-gluconate dehydrogenase(6-PGD), phosphoglucose isomerase(PGI) and phospho-glucomutase(PGM) from skeletal muscle, liver, heart and gill tissues in all three species were analyzed. Chum and masu salmon showed no polymorphic patterns in all isozyme loci, however rainbow trout were found to have polymorphic patterns at MDH-B, LDH and IDH loci. Especially, significant differences were found at MDH-B loci between the three species and the IDH patterns of rainbow trout were also different from the other two species. These loci therefore can be utilized as efficient genetic markers for the identification of hybrids and improve the efficiency of fish breeding. There was no difference except PGI between diploid and triploid isozyme patterns but PGI showed some potential as a marker for triploid in masu salmon.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.12
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• pp.7261-7264
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• 2013

Recent genome wide sequencing has identified mutations in IDH1/IDH2 predominantly in grade II-III gliomas and secondary glioblastomas which are associated with favorable clinical outcome. These mutations have become molecular markers of significant diagnostic and prognostic relevance in the assessment of human gliomas. In the current study we evaluated IDH1 (R132) and IDH2 (R172) in 32 gliomas of various grades and tumor subtypes. Sequencing analysis revealed R132H mutations in 18.7% tumors, while none of the cases showed IDH2 (R172) mutations. The frequency of IDH1 mutations was higher in females (21.4%) than males (11.1%), and it was significantly higher in younger patients. Histological analyses demonstrated presence of necrosis and micro vascular proliferation in 69% and 75% respectively. Interestingly, IDH1 mutations were predominantly present in non-necrotic tumors as well as in cases showing microvascular proliferation. Of the six IDH1 positive cases, three were glioblastomas (IV), and one each were anaplastic oligoastrocytoma (III), anaplastic oligodendroglioma III (n=1) and diffuse astrocytoma. In conclusion, IDH1 mutations are quite frequent in Indian glioma patients while IDH2 mutations are not observed. Since IDH mutations are associated with good prognosis, their use in routine clinical practice will enable better risk stratification and management of glioma patients.