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Mitsuru Emi

Publications and source records attributed to Mitsuru Emi.

At least 19 recordsLinked to original sources

A single nucleotide polymorphism in the CCL1 gene predicts acute exacerbations in chronic obstructive pulmonary disease.

RATIONALE: Acute exacerbations (AEs) in chronic obstructive pulmonary disease (COPD) are a major cause of morbidity and mortality in COPD. OBJECTIVES: The marked heterogeneity in the host defense mechanisms may be attributed to single nucleotide polymorphisms (SNPs) in the inflammatory chemokines that show enhanced expression in the airway of patients with COPD who experience AEs. METHODS: We investigated four SNPs of the CCL11, CCL1, and CCL5 genes in relation to the frequency and severity of AEs in retrospective and prospective studies of a cohort of 276 male patients with COPD. MEASUREMENTS AND MAIN RESULTS: In the 2-yr retrospective study , one SNP (National Center for Biotechnology Information SNP reference: rs2282691) in the predicted enhancer region of the CCL1 gene, encoding a chemotactic factor for a series of leukocytes, was significantly associated with the frequency of AEs in a dominant model (Fisher's exact test: odds ratio [OR], 2.70; 95% confidence interval [CI], 1.36-5.36; p=0.004; logistic regression: OR, 3.06; 95% CI, 1.46-6.41; p=0.003; and Kruskal-Wallis test: p=0.003). In the 30-mo prospective study, the "A" allele was a significant risk allele for the severity of AEs, with a gene-dosage effect (Kaplan-Meier method with log-rank test: AA vs. TT; log-rank statistic: 7.67, p=0.006; Cox proportional hazards regression method: OR, 5.93; 95% CI, 1.28-27.48; p=0.023). The electromobility shift assay showed that C/EBPbeta, a key transcriptional factor in response to pulmonary infections, binds to the "T" allele, but not to the "A" allele. CONCLUSIONS: Variants in the CCL1 gene are associated with susceptibility to AEs through their potential implication in the host defense mechanisms against AEs.

Aged↗

Osteopontin is associated with nuclear factor kappaB gene expression during tail-suspension-induced bone loss.

Osteoporosis due to unloading-induced bone loss is a critical issue in the modern aging society. Although the mechanisms underlying this phenomenon are largely unknown, osteopontin (OPN) is one of the critical mediators required for unloading-induced bone loss [M. Ishijima, S.R. Rittling, T. Yamashita, K. Tsuji, H. Kurosawa, A. Nifuji, D.T. Denhardt, and M. Noda, Enhancement of osteoclastic bone resorption and suppression of osteoblastic bone formation in response to reduced mechanical stress do not occur in the absence of osteopontin, J Exp Med, 193 (2001) 399-404]. To clarify the molecular bases for OPN actions, we carried out microarray analyses on the genes expressed in the femoral bone marrow cells in wild type and OPN-/- mice. The removal of the mechanical load induced bone loss in wild type, but not in OPN-/- mice, as previously reported. Expression analysis of 9586 cDNAs on a microarray system revealed that OPN deficiency blocked tail-suspension-induced expression of ten genes (group A). This observation was confirmed based on semi-quantitative RT-PCR analyses. On the other hand, expression of four genes (group B) was not altered by tail suspension in wild type but was enhanced in OPN-deficient mice. NF-kappaB p105 subunit gene (Nfkb1) was found in group A and Bax in group B. p53 gene expression was upregulated by tail suspension in wild type mice, but it was no longer observed in OPN-/- mice. These data indicate that OPN acts to mediate mechanical stress signaling upstream to the genes encoding apoptosis-related molecules, and its action is associated with alteration of the genes.

Animals↗

Nucleotide variations in genes encoding plasminogen activator inhibitor-2 and serine proteinase inhibitor B10 associated with prostate cancer.

Genes encoding the serine proteinase inhibitor B family (SERPINBs) are mainly clustered on human chromosome 18 (18q21). Several serpins are known to affect malignant phenotypes of tumor cells, so aberrant genetic variants in this molecular family are candidates for conferring susceptibility for risk of cancer. We investigated whether eight selected non-synonymous variations within SERPINB loci at 18q21 might be associated with risk of prostate cancer in Japanese men. A case-control study involving 292 prostate-cancer patients and 384 controls revealed significant differences in regard to distribution of four missense variations in genes encoding plasminogen activator inhibitor 2 (PAI2) and SERPINB10. The most significant association was detected for the N120D polymorphism in the PAI2 gene (P = 5.0 x 10(-5)); men carrying the 120-N allele (120-N/N and 120-N/D genotypes) carried a 2.4-fold increased risk of prostate cancer (95% confidence interval 1.45-4.07). Associations were also detected for three other missense polymorphisms in those two genes. Strong linkage disequilibrium in the region encompassing PAI2 and SERPINB10 extended to about 50 kbp. The results suggested that missense variations in one or both of these genes confer important risks for prostate cancer, and may be themselves tumorigenic. Although confirmative replication studies on larger cohorts are awaited, clinical examination of these variations may become useful for identifying individuals at high risk for prostate cancer.

Alleles↗

Overexpressed in anaplastic thyroid carcinoma-1 (OEATC-1) as a novel gene responsible for anaplastic thyroid carcinoma.

BACKGROUND: Anaplastic thyroid carcinoma (ATC) is one of the most fulminant human malignancies. However, the molecular carcinogenic mechanisms of ATC are understood poorly. Recently, the authors performed a cyclic DNA (cDNA) microarray analysis with 11 anaplastic thyroid carcinoma cell lines (ACLs) and discovered several novel responsible genes for ACLs and ATC. From the extended list, they focused on hypothetical and anonymous genes and investigated a novel gene, named the overexpressed in anaplastic thyroid carcinoma-1 (OEATC-1) gene. METHODS: To investigate the role of the OEATC-1 gene in ATC carcinogenesis, first, the expression levels of OEATC-1 in ACLs, in various types of carcinoma cell lines, and in normal human tissues were examined with reverse transcriptase-polymerase chain reaction analysis. To explore the effect of OEATC-1 in ATC development, a cell-growth assay was performed with KTA2 cells under OEATC-1 gene silencing using small-interfering RNA (siRNA). RESULTS: OEATC-1 was overexpressed significantly in ACLs and in other types of carcinoma cell lines with various expression levels. Conversely, in normal human tissues, OEATC-1 was expressed weakly in placenta, kidney, spleen, thymus, small intestine, and thyroid gland. To evaluate the effects of OEATC-1 on tumor cell growth, gene silencing was caused by transfecting the plasmid-generating siRNA effect to KTA2 cells. Consequently, the silencing of OEATC-1 significantly suppressed the cell growth compared with controls. CONCLUSIONS: The current results indicated that OEATC-1 may have some oncogenic or cell growth-promoting function in ACL. OEATC-1 is considered a novel responsible gene in ATC.

Carcinoma↗

Association of single nucleotide polymorphisms in the promoter region of the pro-opiomelanocortin gene (POMC) with low bone mineral density in adult women.

Among multiple factors influencing osteoporosis, genetic variations involved in bone-mineral metabolism can affect risks predisposing to the disease onset. Here, we studied single-nucleotide polymorphisms (SNPs) in the pro-opiomelanocortin (POMC) gene for possible association with bone mineral density (BMD) among 384 adult Japanese women and observed significant correlation between adjusted BMD and three SNPs in the promoter region (r>0.14, p<0.01). The most significant correlation was observed for -2353G/A (r=-0.16, p=0.002); homozygous carriers of the major (G) allele had the highest BMD (0.405+/-0.054 g/cm2) while heterozygous carriers were intermediate (0.390+/-0.053 g/cm2) and homozygous A-allele carriers had the lowest BMDs (0.369+/-0.048 g/cm2). Although no association was detected between these SNPs and body weight or body mass index (BMI), significant association was detected between the -2313A/C genotype and plasma total cholesterol level (r=-0.12, p=0.019). We propose that POMC is among the likely susceptibility genes for osteoporosis and may also be involved in dyslipidemia.

Adult↗

Association of nucleotide variations in the apolipoprotein B48 receptor gene (APOB48R) with hypercholesterolemia.

Factors predisposing to the phenotypic features of high total cholesterol (T-Cho) in human plasma have not been clearly defined. Here we report an association between two variations in the apolipoprotein B48 receptor gene (APOB48R) and plasma T-Cho levels among 352 adult individuals in Japan. By analyzing phenotypic associations between age- and gender-adjusted levels of plasma T-Cho, low-density lipoprotein (LDL) cholesterol (LDL-C), and high-density lipoprotein (HDL) cholesterol (HDL-C), we detected a significant correlation between genotypes of the A419P variation and adjusted T-Cho levels. Among homozygous G-allele carriers (n=265), heterozygous carriers (n=78), and homozygous minor C-allele carriers (n=9), T-Cho levels were 2.43+/-0.21 mg/cm(3), 2.48+/-0.24 mg/cm(3), and 2.63+/-0.21 mg/cm(3), respectively, indicating a codominant T-Cho-elevating effect of the minor C-allele (r=0.15, P=0.007). A similar effect was detected for c.934-960/del (r=0.13, P=0.015). Linkage disequilibrium (LD) analysis detected significant LD among eight variant sites that included neighboring loci. Our results indicate that variations in APOB48R and nearby genes are among the many factors involved in hypercholesterolemia. The etiological studies should now include consideration of this novel aspect of the mechanism(s) leading to hypercholesterolemic disease.

Aged↗

[Genetic analysis of osteoporosis susceptibility: future perspectives on genome wide analysis].

Genetic susceptibility of osteoporosis has been analyzed mainly via sib-pair analysis and association study on candidate genes, however these approaches might have substantial limitation. Recently proposed genome wide analysis of association using high density polymorphic markers has not been established on this field. Preferable phenotypes and suitable subjects have to be defined as well as for tag-SNP selection and the method of multi-step screening.

Genetic Predisposition to Disease↗

The important role for betaVLDLs binding at the fourth cysteine of first ligand-binding domain in the low-density lipoprotein receptor.

The low-density lipoprotein (LDL) receptor (LDLR) is a crucial role for binding and uptaking apolipoprotein (apo) B-containing lipoproteins, such as very-low-density lipoprotein (VLDL), intermediate-density lipoprotein (IDL), and LDL. The defect function of the LDLR causes familial hypercholesterolemia (FH), the phenotype of which is elevated plasma cholesterol and premature coronary heart disease (CHD). In the present study, we characterize the role of the cysteine residue of the ligand-binding domain of the LDLR. The mutant LDLR protein of cysteine for serine at codon 25 (25S-LDLR) was expressed in Chinese hamster ovary (CHO) cell line, ldl-A7. By Western blot analysis, the 25S-LDLR was detected with monoclonal antibody IgG-12D10, which reacts with the linker site of the LDLR but not with IgG-C7, which reacts with the NH2 terminus of the receptor. The 25S-LDLR bound LDL similarly to the wild-type LDLR, but the rate of uptake of LDL by the mutant receptor was only about half of that by the wild-type receptor. In contrast, the 25S-LDLR bound and internalized beta VLDL more avidly than LDL. These results suggest that the fourth cysteine residue of the first ligand-binding domain of the LDLR might be important for the internalization of atherogenic lipoproteins by vascular cells despite reduced LDL uptake, leading to atherosclerosis and premature cardiovascular disease.

Animals↗

Gene expression patterns as marker for 5-year postoperative prognosis of primary breast cancers.

PURPOSE: To establish the novel prognostic markers for breast cancer, gene expression profile was examined genome-wide. METHODS: We used cDNA microarray consisting of 18,432 human genes to compare genome-wide expression profiles of eight primary breast cancers, four from patients who died of breast cancer within 5 years after surgery (5D group) and four who survived disease-free for more than 5 years (5S group). RESULTS: We identified 21 genes whose expression was greater in tumors from the 5D group than in 5S tumors, and 23 with higher expression in the 5S group than in the 5D group. We established a Prognostic Index (PI) for prediction of postoperative prognosis, based on the aberrant expression profiles of ten of those genes. Among 20 additional cases chosen blindly, ten presented with high prognostic scores (>7, good) according to the PI; the remaining ten cases revealed scores <7 (poor). The PI predicted the actual 5-year clinical outcomes of these 20 cases with 100% accuracy. CONCLUSION: Our PI system is reliable in clinical settings for predicting postoperative risk for breast cancer. The extensive list of genes provides valuable information about progression of breast cancer and suggests potential target molecules for treating this disease.

Adult↗

Functional impairment of two novel mutations detected in lipoprotein-associated phospholipase A2 (Lp-PLA2) deficiency patients.

Plasma lipoprotein-associated phospholipase A2 (Lp-PLA2), also known as platelet-activating factor (PAF) acetylhydrolase (PAF-AH), is a member of the serine-dependent class of A2 phospholipases that hydrolyze sn2-ester bonds of fragmented or oxidized phospholipids at sites where atherosclerotic plaques are forming. Most circulating Lp-PLA2 is bound to low-density lipoprotein (LDL) particles in plasma and the rest to high-density lipoprotein (HDL). Deficiency of Lp-PLA2 is a predisposing factor for cardiovascular diseases in the Japanese population. We describe here two novel mutations of the gene encoding Lp-PLA2, InsA191 and I317N in Japanese subjects. The first patient, with partial Lp-PLA2 deficiency, was heterozygous for the InsA191 mutation; macrophages from this patient secreted only half the normal amount of Lp-PLA2 in vitro. The other patient, who showed complete Lp-PLA2 deficiency, was a compound heterozygote for the novel I317N mutation and a common V279F mutation; macrophages from that patient failed to secrete any Lp-PLA2. Measurement of Lp-PLA2 mass, activity and Western blotting verified impaired production and secretion of the enzyme after transfection of mutant construct into COS-7 cells. These results indicated that both novel mutants, InsA191 and I317N, impair function of the Lp-PLA2 gene.

1-Alkyl-2-acetylglycerophosphocholine Esterase↗

Amplification, up-regulation and over-expression of C3G (CRK SH3 domain-binding guanine nucleotide-releasing factor) in non-small cell lung cancers.

The Ras-CRK-Rap1 cellular signal-transduction system is regulated by guanine nucleotide exchange factors (GEFs). Transcription of C3G on chromosome 9q34 and a key member of the GEF gene family is activated by the CRK-adaptor protein; the C3G product is a CRK SH3 domain-binding guanine nucleotide-releasing factor. We document here the amplification of C3G in five of 18 primary non-small cell lung cancers examined and its increased expression in 18 of 28 tumors in comparison to corresponding non-cancerous lung tissues. Immunohistochemical staining revealed prominent C3G protein in the cytoplasm of cancer cells, associated with faint staining at the nucleolar membrane, but C3G was not detectable in normal bronchial mucoepithelial cells or in broncholoalveolar cells of the bronchial/bronchiolar ducts or alveoli. These data indicate that amplification and increased expression of the C3G gene may play some role in human lung carcinogenesis through derangement of the CRK-Rap1 signaling pathway.

Adaptor Proteins, Signal Transducing↗

Up-regulation of transcriptional factor E2F1 in papillary and anaplastic thyroid cancers.

Expression of genes in the Rb-E2F signaling pathway is controlled by E2F transcriptional factors originally defined as molecules that bind to the promoter of E2 adenovirus. The E2F gene family consists of six members and is designated E2F1-6. The Rb-E2F signaling pathway is among the main regulators of the cell cycle, hence its importance in differentiation and oncogenesis. We document here up-regulation of E2F1, but not other members of the E2F gene family, in 15 of 18 primary papillary thyroid cancers examined (83%) in comparison to corresponding noncancerous thyroid tissues and in all of 11 anaplastic thyroid cancer (ATC) cell lines (100%). The E2F4 gene, however, was down-regulated in 12 of the papillary thyroid cancers (67%). Immunohistochemical analysis with antibody to E2F1 revealed prominent intracellular E2F1 protein in most of the primary papillary cancers (16 of 18; 89%) but was not detectable in normal thyroid tissues. These data indicated that increased expression of the E2F1 gene might play a significant role in human thyroid carcinogenesis through derangement of the Rb-E2F signaling pathway.

Adult↗

Natural selection and population history in the human angiotensinogen gene (AGT): 736 complete AGT sequences in chromosomes from around the world.

Several lines of evidence suggest that patterns of genetic variability in the human angiotensinogen gene (AGT) contribute to phenotypic variability in human hypertension. The A(-6) promoter variant of AGT is associated with higher plasma angiotensinogen levels and increased risk of essential hypertension. The geographic distribution of the A(-6) variant leads to the intriguing hypothesis that the G(-6) promoter variant has been selectively advantageous outside Africa. To test these hypotheses, we investigated the roles of population history and natural selection in shaping patterns of genetic diversity in AGT, by sequencing the entire AGT gene (14400 bp) in 736 chromosomes from Africa, Asia, and Europe. We found that the A(-6) variant is present at higher frequency in African populations than in non-African populations. Neutrality tests found no evidence of a departure from selective neutrality, when whole AGT sequences were compared. However, tests restricted to sites in the vicinity of the A(-6)G polymorphism found evidence of a selective sweep. Sliding-window analyses showed that evidence of the sweep is restricted to sites in tight linkage disequilibrium (LD) with the A(-6)G polymorphism. Further, haplotypes carrying the G(-6) variant showed elevated levels of LD, suggesting that they have risen recently to high frequency. Departures from neutral expectation in some but not all regions of AGT indicate that patterns of diversity in the gene cannot be accounted for solely by population history, which would affect all regions equally. Taken together, patterns of genetic diversity in AGT suggest that natural selection has generally favored the G(-6) variant over the A(-6) variant in non-African populations. However, important localized effects may also be present.

Africa↗

Association of multiple nucleotide variations in the pituitary glutaminyl cyclase gene (QPCT) with low radial BMD in adult women.

UNLABELLED: Correlation between 13 genetic variations of the glutaminyl-peptide cyclotransferase gene and adjusted aBMD was tested among 384 adult women. Among 13 variations with strong linkage disequilibrium, R54W showed a prominent association (p = 0.0003), which was more striking when examined among 309 elder subjects (> or =50 years; p = 0.0001). Contribution for postmenopausal bone loss was suggested. INTRODUCTION: Alterations in homeostatic regulation of estrogen through the hypothalamus-pituitary-gonadal axis (HPG axis) importantly affect the pathogenesis of osteoporosis. Osteoporosis-susceptibility genes have been proposed in this hormonal axis, such as estrogen receptor genes and the gonadotropin-releasing hormone gene (GnRH). Here we report another example of genes: glutaminyl-peptide cyclotransferase gene (QPCT), an essential modifier of pituitary peptide hormones, including GnRH. MATERIALS AND METHODS: Analyses of association of 13 single nucleotide polymorphisms (SNPs) at the QPCT locus with adjusted areal BMD (adj-aBMD) were carried out among 384 adult women. Linkage disequilibrium (LD) was analyzed by haplotype estimation and calculation of D' and r2. Multiple regression analysis was applied for evaluating the combined effects of the variations. RESULTS AND CONCLUSIONS: LD analysis indicated strong linkage disequilibrium within the entire 30-kb region of the QPCT gene. Significant correlations were observed between the genotypes of the six SNPs and the radial adj-aBMD, among which R54W (nt + 160C>T) presented the most prominent association (p = 0.0003). Striking association was observed for these SNPs among the 309 subjects >50 years of age (R54W, p = 0.0001; -1095T>C, p = 0.0002; -1844C>T, p = 0.0002). Multiple regression analyses indicated that multiple SNPs in the gene might act in combination to determine the radial adj-aBMD. These results indicate that genetic variations in QPCT are the important factors affecting the BMD of adult women that contribute to susceptibility for osteoporosis. The data should provide new insight into the etiology of the disease and may suggest a new target to be considered during treatment.

Adult↗

Association of a single-nucleotide polymorphism in low-density lipoprotein receptor-related protein 5 gene with bone mineral density.

Low-density lipoprotein receptor-related protein 5 (LRP5) is an important regulator of osteoblast growth and differentiation, affecting peak bone mass in vertebrates. Here, we analyzed whether the LRP5 gene was involved in the etiology of postmenopausal osteoporosis, using association analysis between bone mineral density (BMD) and an LRP5 gene single-nucleotide polymorphism (SNP). Association of an SNP in the LRP5 gene at IVS17-1677C > A (intron 17) with BMD was examined in 308 postmenopausal Japanese women (65.2 +/- 9.6 years; mean +/- SD). The subjects bearing at least one variant A allele (CA + AA; n = 142) had significantly lower Z scores for total body and lumbar BMD than the subjects with no A allele (CC; n = 166) (total body, 0.08 +/- 1.09 versus 0.50 +/- 1.03; P = 0.0022; lumbar spine, -0.42 +/- 1.43 versus -0.02 +/- 1.42; P = 0.013). These findings suggest that the LRP5 gene is a candidate for the genetic determinants of BMD in postmenopausal women, and this SNP could be useful as a genetic marker for predicting the risk of osteoporosis.

Aged↗

Characterization of liver-cirrhosis nodules by analysis of gene-expression profiles and patterns of allelic loss.

To disclose genetic mechanisms involved in development or progression of hepatocellular carcinoma (HCC), we used a genome-wide cDNA microarray consisting of 8,448 genes to compare gene-expression profiles among 12 liver-cirrhosis nodules (LCNs) and five specimens of HCC excised from a single patient and carefully prepared by laser-capture microdissection (LCM). The expression patterns enabled us to identify 72 genes that were frequently upregulated and 57 that were downregulated specifically in the LCN specimens as compared to the HCCs. We also documented upregulation of 31 genes and downregulation of seven others in both HCC and LCN tissues. Several types of intracellular kinase, including receptor-type kinase, were upregulated in LCNs. Expression patterns of HCCs and LCNs generally represented two genetically distinct groups when subjected to a hierarchical clustering analysis, although expression profiles of two of the LCNs resembled the HCC pattern. Analysis of allelic losses at microsatellite loci revealed that LCNs showed frequent loss of heterozygosity (LOH) (33%) in chromosomal regions 6q and 22q; over half of the LCNs had lost an allele for at least one of the 28 loci examined. The presence of early genetic changes among LCNs, with additional genetic changes occurring during formation of HCCs, suggests that hepatocellular carcinogenesis follows the multistep model established for colon cancers and that some LCNs may be precancerous lesions.

Carcinoma, Hepatocellular↗

Up-regulation of CC chemokine, CCL3L1, and receptors, CCR3, CCR5 in human glioblastoma that promotes cell growth.

Human CC ligand 3-like protein 1 (CCL3L1), a member of the CC chemokine family, that induces MCP1 and RANTES, exhibits a variety of proinflammatory activities including chemotaxis, and functional and proliferative activation of leukocytes, lymphocytes and macrophages. Its signal is transmitted through transmembrane receptors, CC chemokine receptors, CCR1, CCR3 and CCR5. To examine gene expression of chemokine, CCL3L1, and its receptors, CCR1, CCR3 and CCR5, we analyzed tumor tissues from 21 patients with several types of primary gliomas. CCL3L1, CCR3 and CCR5 gene exhibited over-expression in 70% (7/10), 60% (6/10), and 60% (6/10) of glioblastoma, in comparison with lower frequencies seen in lower-grade gliomas. Transfection of CCL3L1-expression vector to glioblastoma cell line enhanced proliferation of the tumor cells. These data suggest that increased expression of the CCL3L1, CCR3 and CCR5 chemokine-receptors system is involved in brain tumorigenesis, especially in the progression of glioblastoma.

Brain Neoplasms↗

Hypermethylation-associated inactivation of the SOCS-1 gene, a JAK/STAT inhibitor, in human pancreatic cancers.

BACKGROUND: SOCS-1, a JAK-binding protein (SSI-1/SOCS-1/JAB), regulates the JAK/STAT signal transduction pathway that relays signals from various cytokines in the extracellular matrix into the cell. Inactivation of the SOCS-1 gene by methylation has been previously described in hepatocellular carcinomas and multiple myeloma. The purpose of the present work was to analyze the expression of the SOCS-1 gene and identify inactivation of this gene by methylation in pancreatic cancers. METHODS: 20 samples were analyzed. We identified the expression of SOCS-1 gene using RT-PCR and the mechanism of inactivation in this gene by methylation assay. RESULTS: We documented marked suppression of SOCS-1 mRNA and reduction of SOCS-1 protein in 7 of 14 primary pancreatic cancers examined; moreover, CpG-rich regions upstream of the SOCS-1 gene were hypermethylated in 8 of the 14 tumors. CONCLUSIONS: The results suggested that this gene is silenced in a substantial portion of pancreatic cancers through mechanisms that cause methylation in the promoter region.

Aged↗