• Molecules and Cells
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• v.40 no.10
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• pp.761-772
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• 2017

Glioblastoma is the most frequent and most aggressive brain tumor in adults. Solute carrier family 8 member 2 (SLC8A2) is only expressed in normal brain, but not present in other human normal tissues or in gliomas. Therefore, we hypothesized that SLC8A2 might be a glioma tumor suppressor gene and detected the role of SLC8A2 in glioblastoma and explored the underlying molecular mechanism. The glioblastoma U87MG cells stably transfected with the lentivirus plasmid containg SLC8A2 (U87MG-SLC8A2) and negative control (U87MG-NC) were constructed. In the present study, we found that the tumorigenicity of U87MG in nude mice was totally inhibited by SLC8A2. Overexpression of SLC8A2 had no effect on cell proliferation or cell cycle, but impaired the invasion and migration of U87MG cells, most likely through inactivating the extracellular signal-related kinases (ERK)1/2 signaling pathway, inhibiting the nuclear translocation and DNA binding activity of nuclear factor kappa B ($NF-{\kappa}B$), reducing the level of matrix metalloproteinases (MMPs) and urokinase-type plasminogen activator (uPA)-its receptor (uPAR) system (ERK1/2-$NF-{\kappa}B$-MMPs/uPA-uPAR), and altering the protein levels of epithelial to mesenchymal transitions (EMT)-associated proteins E-cardherin, vimentin and Snail. In addition, SLC8A2 inhibited the angiogenesis of U87MG cells, probably through combined inhibition of endothelium-dependent and endothelium-nondependent angiogenesis (vascular mimicry pattern). Totally, SLC8A2 serves as a tumor suppressor gene and inhibits invasion, angiogenesis and growth of glioblastoma.

• The Korean Journal of Physiology and Pharmacology
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• v.28 no.2
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• pp.113-120
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• 2024

Solute carrier 40A1 (SLC40A1) encodes ferroportin, which is the only known transmembrane protein that exports elemental iron from mammalian cells and is essential for iron homeostasis. Mutations in SLC40A1 are associated with iron-overload disorders. In addition to ferroportin diseases, SLC40A1 expression is downregulated in various cancer types. Despite the clinical significance of the SLC40A1 transporter, only a few studies have investigated genetic variants in SLC40A1. The present study was performed to identify genetic variations in the SLC40A1 promoter and functionally characterize each variant using in vitro assays. We investigated four haplotypes and five variants in the SLC40A1 promoter. We observed that haplotype 3 (H3) had significantly lower promoter activity than H1, whereas the activity of H4 was significantly higher than that of H1. Luciferase activity of H2 was comparable to that of H1. In addition, four variants of SLC40A1, c.-1355G>C, c.-662C>T, c.-98G>C, and c.-8C>G, showed significantly increased luciferase activity compared to the wild type (WT), whereas c.-750G>A showed significantly decreased luciferase activity compared to the WT. Three transcription factors, cAMP response element-binding protein-1 (CREB-1), chicken ovalbumin upstream promoter transcription factor 1, and hepatic leukemia factor (HLF), were predicted to bind to the promoter regions of SLC40A1 near c.-662C>T, c.-98G>C, and c.-8C>G, respectively. Among these, CREB1 and HLF bound more strongly to the variant sequences than to the WT and functioned as activators of SLC40A1 transcription. Collectively, our findings indicate that the two SLC40A1 promoter haplotypes affect SLC40A1 transcription, which is regulated by CREB-1 and HLF.

• Korean Journal of Clinical Laboratory Science
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• v.51 no.3
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• pp.286-293
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• 2019

Hypertension (HTN) is one of the major chronic diseases, and HTN is defined as being in a state of continuous high blood pressure. Left ventricular hypertrophy (LVH) is a condition in which the mass of the left ventricle has increased, and HTN is a leading cause of LVH. HTN and LVH are known to be caused by the interaction of environmental factors and genetic factors. It has been reported that the polymorphisms of SLC8A1, among the genetic factors that affect high blood pressure, are related to salt sensitivity hypertension. In this study, the genetic polymorphisms of SLC8A1 were chosen based on the Korean Genome and Epidemiology data. Logistic regression analysis was then performed for HTN and LVH. Linear regression analysis was also performed for systolic blood pressure (SBP) and diastolic blood pressure (DBP). As a result, 5 SNPs showed statistically significant associations (P<0.05) with HTN, and 10 SNPs showed statistically significant associations with LVH. rs1002671 and rs9789739 showed significant correlation at the same time with HTN and LVH. These results suggest that the polymorphisms of the SLC8A1 gene are linked to the development of HTN and LVH in Koreans. We expect these results to help us understand the pathogenic mechanisms for HTN and LVH.

• Reproductive and Developmental Biology
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• v.33 no.4
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• pp.211-216
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• 2009

A cell frequently utilizes glucose as a fuel of energy and a major substrate of lipid and protein syntheses. A regulation of glucose movement into and out of the cells is precisely controlled by cooperative works of passive and sodium-dependent active processes. At least 13 glucose cotransporter (Slc2a, GLUT) isoforms involve in passive movement of glucose in cells. The efferent ductules (EDs) play in a number of important functions for maintenance of male fertility. In the present study, using real-time PCR analysis, we determined gene expression of five Slc2a isoforms in the EDs. In addition, we compared expression levels of these Slc2a isoforms according to postnatal development ages, 1 week, 2 weeks, 1 month, and 3 months. Results from the current study showed that expression of Slc2a1, Slc2a3, and Slc2a5 mRNAs reached the highest levels at 1 month of age, followed by a transient decrease at 3 months of age. In addition, the level of Slc2a4 mRNA reminded at steady until 1 month of age and was significantly reduced at 3 months of age, whereas the highest level of Slc2a 8 mRNA was detected at 2 weeks of age. Data from the present study indicate a differential expression of various Slc2a isoforms in the ED according to postnatal ages. Thus, it is believed that glucose movement through the epithelial cells in the ED would be regulated by the coordinated manner among Slc2a isoforms expressed at a given age.

• YAKHAK HOEJI
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• v.54 no.1
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• pp.49-54
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• 2010

SLC6A19 which reported as a neurotransmitter was composed of seven minisatellites. In previous our study, the minisatellites variants of SLC6A19-MS7 showed the susceptibility for hypertension. When this minisatellte sequences were analyzed using the bioinformatic tool, USF1 (upstream transcription factor 1) was found in this region as a putative transcription factor binding site. USF1 is binding with E-boxes which has a consensus sequence of CACGTG. USF1 is a ubiquitously expressed transcription factor and involved in the transcriptional control of many genes including the molecular pathogenesis of cardiovascular disease. Thus, we investigated that the putative functional relationship between the minisatellites variants and susceptibility for myocardial infarction. A case-control study was performed that compared genomic DNA from 400 controls and 225 cases with myocardial infarction. There were no significant differences observed in the overall allelic distribution of minisatellites between controls and cases, which indicates that this polymorphism is not responsible for myocardial infarction susceptibility. Hence, we analyzed the five different minisatellites alleles from this study and characterized 14 different repeats units (Unit1~Unit14). Then, we evaluated the DNA composition, phylogenic tree, and pairwise distances of its repeats. The variability of each repeats differed from 2.33% to 16%. The phylogenic trees for the four SLC6A19-MS7 minisatellites exhibited very different shapes in their braches and distances, and present most common 8 repeats allele was the longest 14 repeats allele. Therefore, this result may help to understand for the evolutional level of the length of minisatellites.

• The Korean Journal of Physiology and Pharmacology
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• v.19 no.4
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• pp.319-325
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• 2015

Among solute carrier proteins, the organic anion transporters (OATs) play an important role for the elimination or reabsorption of endogenous and exogenous negatively charged anionic compounds. Among OATs, SLC22A9 (hOAT7) transports estrone sulfate with high affinity. The net decrease of estrogen, especially in post-menopausal women induces rapid bone loss. The present study was performed to search the SNP within exon regions of SLC22A9 in Korean females with osteoporosis. Fifty healthy controls and 50 osteoporosis patients were screened for the genetic polymorphism in the coding region of SLC22A9 using GC-clamped PCR and denaturing gradient gel electrophoresis (DGGE). Six SNPs were found on the SLC22A9 gene from Korean women with/without osteoporosis. The SNPs were located as follows: two SNPs in the osteoporosis group (A645G and T1277C), three SNPs in the control group (G1449T, C1467T and C1487T) and one SNP in both the osteoporosis and control groups (G767A). The G767A, T1277C and C1487T SNPs result in an amino acid substitution, from synonymous vs nonsynonymous substitution arginine to glutamine (R256Q), phenylalanine to serine (F426S) and proline to leucine (P496L), respectively. The Km values and Vmax of the wild type, R256Q, P496L and F426S were 8.84, 8.87, 9.83 and $12.74{\mu}M$, and 1.97, 1.96, 2.06 and 1.55 pmol/oocyte/h, respectively. The present study demonstrates that the SLC22A9 variant F426S is causing inter-individual variation that is leading to the differences in transport of the steroid sulfate conjugate (estrone sulfate) and, therefore this could be used as a marker for certain disease including osteoporosis.

• Clinical and Experimental Pediatrics
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• v.59 no.sup1
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• pp.29-31
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• 2016

Glucose transport 1 (GLUT-1) deficiency is a rare syndrome caused by mutations in the glucose transporter 1 gene (SLC2A1) and is characterized by early-onset intractable epilepsy, delayed development, and movement disorder. De novo mutations and several hot spots in N34, G91, R126, R153, and R333 of exons 2, 3, 4, and 8 of SLC2A1 are associated with this condition. Seizures, one of the main clinical features of GLUT-1 deficiency, usually develop during infancy. Most patients experience brief and subtle myoclonic jerk and focal seizures that evolve into a mixture of different types of seizures, such as generalized tonic-clonic, absence, myoclonic, and complex partial seizures. Here, we describe the case of a patient with GLUT-1 deficiency who developed infantile spasms and showed delayed development at 6 months of age. She had intractable epilepsy despite receiving aggressive antiepileptic drug therapy, and underwent a metabolic workup. Cerebrospinal fluid (CSF) examination showed CSF-glucose-to-blood-glucose ratio of 0.38, with a normal lactate level. Bidirectional sequencing of SLC2A1 identified a missense mutation (c.1198C>T) at codon 400 (p.Arg400Cys) of exon 9.

• Journal of Genetic Medicine
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• v.18 no.1
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• pp.44-47
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• 2021

Cerebral creatine deficiency syndrome (CCDS) is a disorder where a defect is present in transport of creatine in the brain. Creatine plays an essential role in the energy metabolism of the brain. This is a genetic disorder, autosomal recessive or X linked, characterized by intellectual disability, speech and language delay, epilepsy, hypotonia, etc. Until recently very few number of cases have been reported. Here we report a case of 1.5-year-old boy who had epilepsy (epileptic spasm and generalized tonic clonic seizure), intellectual disability, microcephaly, hypotonia and speech delay. His magnetic resonance imaging of brain showed cortical atrophy and electroencephalography showed burst suppression pattern. The diagnosis was confirmed by clinical exome sequencing which showed novel mutation of SLC6A8+ in exon 9, suggestive of X linked recessive CCDS. The patient was then treated with glycine, L-arginine and creatine monohydrate with multiple antiepileptic drugs.

• Journal of Embryo Transfer
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• v.25 no.1
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• pp.29-34
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• 2010

Follicular cystic ovary (FCO) is one of the major causes of reproductive failure in cattle. Genetic alterations affect the function of diverse cells and/or tissues, which could be present in cystic ovaries. A microarray analysis was performed to screen differential gene expressions in follicular cystic follicles of cattle. In this study, we hypothesized that follicular cysts may be induced by changes in ion- and transporter-related gene expression. Microarray data showed that fibrinogen-gamma (FGG) and low density lipoprotein receptor-related protein 8 (LRP8) were up-regulated, while choline transporter-like protein 4 (SLC44A4), very long-chain acyl-CoA synthetase homolog 2 (SLC27A5), annexin 8 (ANXA8), and aquaporin 4 were down-regulated in follicular cystic follicles. A semi-quantitative RT-PCR was carried out to validate DEGs altered in follicular cystic follicles. Of six DEGs, three DEGs (FGG, SLC44A4, and aquaporin 4) showed a positive correlation between microarray and semi-quantitative PCR data. We focused on FGG, among three DEGs, which was highly up-regulated in follicular cystic follicles. The FGG mRNA was upregulated by 8.4-fold and by 1.7-fold in the bovine follicular cystic follicles as judged by microarray and RT-PCR analysis, respectively. However, there was no significant changes in the expression level of FGG protein in both follicular cystic follicles and granulosa cells isolated from follicular cystic follicles by Western blot analysis. Although this study does not reveal a positive correlation between the mRNA and protein level, FGG appears to be an important biomarker in the discrimination of follicular cyst from normal ovary.

• Childhood Kidney Diseases
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• v.16 no.2
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• pp.121-125
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• 2012

Gitelman syndrome is an autosomal recessive renal tubular disorder characterized by hypokalemic metabolic alkalosis, and it is distinguished from Batter syndrome by hypomagnesemia and hypocalciuria. This disorder is caused by mutation in SLC12A3 gene which encodes thiazide-sensitive $Na^+-Cl^-$cotransporter (NCCT) which is expressed in the apical membrane of cells, lining distal convoluted tubule. A 8-year old boy who presented with Rolandic epilepsy, and horseshoe kidney accidentally showed clinical features of metabolic alkalosis, hypokalemia, hypocalciuria without hypomagnesemia. So we identified a heterozygote mutation and an abnormal splicing in the SLC12A3 gene, encoding NCCT. The mutation was detected in the exon 15 and 22 of SLC12A3 gene.