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M Emi

Publications and source records attributed to M Emi.

At least 37 records · Page 2Linked to original sources
PubMed2001

Novel single nucleotide polymorphisms of the human colony-stimulating factor 2 (CSF2) gene identified by sequencing the entire gene.

We describe three single nucleotide polymorphisms (SNPs) of the human colony-stimulating factor 2 (CSF2) gene and their allelic frequencies, as determined by direct sequencing of 48 alleles of the entire CSF2 gene. Three polymorphisms were identified, at nucleotide positions 1816 (T/C), 2284 (C/T), and 3079 (G/A). These polymorphisms will be useful in genetic studies not only of hematologic disorders but also of disorders of bone metabolism.

Granulocyte-Macrophage Colony-Stimulating Factor↗
PubMed2001

Novel single nucleotide polymorphisms of the human nuclear factor kappa-B 2 gene identified by sequencing the entire gene.

The nuclear factor kappa-B 2 (NFKB2) gene is a member of the NFKB/Rel gene family, which is known to be a pivotal regulator of the acute phase of the inflammatory response and of immune responses. We identified three novel single nucleotide polymorphisms (SNPs) and determined their allelic frequencies, as determined by the sequencing of 48 alleles of the entire gene in a Japanese population sample. Two of the three polymorphisms were identified at nucleotide (nt) position 1837 (T/C) and nt position, 1867 (GG/G) in the upstream region of the gene. The other polymorphism was identified at nt position 2584 (G/T) within intron 1. These polymorphisms will be useful in genetic studies of the processes involved in inflammatory responses and in bone differentiation.

Japan↗
PubMed2001

Inactivation of SSI-1, a JAK/STAT inhibitor, in human hepatocellular carcinomas, as revealed by two-dimensional electrophoresis.

BACKGROUND/AIMS: Hepatocellular carcinoma (HCC) is one of the most common human cancers, and many efforts have been paid to discover aberrant expression control in HCC, however the specific molecular mechanisms involved in hepatocarcinogenesis remain to be determined. METHODS: To investigate genomic changes that occur in human primary hepatocellular carcinomas (HCC), we carried out restriction landmark genomic scanning. This two-dimensional electrophoretic system displays 2000-3000 NotI-landmark sites in a single gel. RESULTS: We detected one landmark spot that showed diminished signal intensities in a majority of the HCCs we examined. Cloning revealed that this spot represented a NotI-cluster sequence that was enriched with CpG dinucleotides in the promoter region of a gene encoding Janus kinase (JAK)-binding protein, SSI-1 (also known as JAB1 or SOCS-1). Expression of the SSI-1 gene was markedly reduced in half of eight HCCs analyzed. CONCLUSIONS: This protein regulates the Janus kinase signal transducers and activators of transcription signal transduction pathway, which transmits signals from cytokines to the intracellular apparatus. These data suggest that dysregulation of the pathway relate with progression of HCC.

Carcinoma, Hepatocellular↗
PubMed2001

Genomic structure of the human MAD2 gene and mutation analysis in human lung and breast cancers.

Some of the many human cancers that exhibit chromosomal instability also carry mutations in mitotic checkpoint genes and/or reveal reduced expression of some of those genes, such as hMAD2. To facilitate investigation of alterations of hMAD2, we determined its genomic structure and intronic primers designed to amplify the entire coding region. Since general impairment of the mitotic checkpoint is frequently reported in lung cancers, and reduced expression of hMAD2 has been reported in breast cancers as well, we searched for mutations throughout the coding sequence of this gene in the genomic DNA of 30 primary lung tumors, 30 lung-cancer cell lines and 48 primary breast cancers. Our approach, which involved polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) analysis and direct sequencing, revealed nucleotide variants in only two of the 108 specimens. One was a cytosine-to-adenine substitution 3 bp upstream of exon 4 that occurred in one lung cancer cell line and one primary breast tumor, a change that did not alter transcriptional sequence. The other was an adenine-to-guanine substitution within exon 4, of the same lung cell line; this change already had been reported as a polymorphism. The results suggested that the hMAD2 gene is not commonly mutated in either lung nor breast cancers. Further studies should focus on other mechanisms that might account for reduced expression of the hMAD2 gene, and/or pursue analyses of other mitotic checkpoint genes for mutations in human cancer. Nevertheless, the genomic structure, the intronic primer sequences, and polymorphisms of the hMAD2 gene presented here will facilitate future studies to determine the full spectrum and frequency of the genetic events that can affect expression of the hMAD2 gene in human tumors.

Breast Neoplasms↗
PubMed2001

Two novel single-nucleotide polymorphisms of the Caspase-9 (CASP9) gene in the Japanese population.

We identified two single-nucleotide polymorphisms (SNPs) in the human Caspase-9 (CASP9) gene (1p36.3), which encodes an apoptosis-related cysteine protease, by screening all exons and exon-intron boundaries. These SNPs were present in coding regions. One of coding SNPs reflected an amino-acid substitution; an A to G transition at codon 221 in exon 5 would encode arginine instead of glutamine. As the gene is implicated in apoptotic cascade, the polymorphic sites will serve as useful markers for genetic studying of disorders affecting immune response and cancer susceptibility in humans.

Caspase 9↗
PubMed2001

Fusion of a sequence from HEI10 (14q11) to the HMGIC gene at 12q15 in a uterine leiomyoma.

Uterine leiomyoma, a benign smooth-muscle tumor of the myometrium, is the most commonly encountered neoplasm in women of reproductive age. Band q15 of chromosome 12 is often rearranged in benign mesenchymal tumors such as uterine leiomyomas, and the HMGIC gene, encoding a protein of the high-mobility-group (HMG), is present in that region. Using 3' rapid amplification of cDNA ends (3'RACE) experiments, we isolated an ectopic sequence that was fused to HMGIC in a uterine leiomyoma. Cloning of the fusion cDNA identified a gene termed rising dbl quote, left (low)homo sapiens enhancer of invasion 10" (HEI10) as the fusion partner. Radiation hybrid mapping revealed that the normal location of HEI10 is at 14q11. In the fusion transcript the first two exons of the HMGIC gene, which encode DNA-binding domains, were fused to the 3' portion of the HEI10 gene. This rearrangement implicates HMGIC in the tumorigenesis of uterine leiomyoma, and suggests that its fusion HMGIC product may play a role in mesenchymal differentiation.

Amino Acid Sequence↗
PubMed2001

Down-regulation in multiple human cancers of a novel gene, DMHC, from 17q25.1 that encodes an integral membrane protein.

Frequent observations of allelic loss in chromosomal band 17q25.1 in a variety of human cancers have suggested that one or more tumor suppressor genes are present in that region. Moreover, a genetic locus for hereditary focal non-epidermolytic palmoplantar keratoderma, a condition associated with cancer of the esophagus (TOC; Tylosis with Oesophageal Cancer), lies in the same region. We screened cell lines derived from a variety of human cancers by reverse transcription-polymerase chain reaction (RT-PCR) to detect alterations in expression of genes within the region in question, by examining expressed sequence tags located there. These experiments identified an 1834-bp full-length cDNA encoding a novel, 441-amino acid integral membrane protein with seven putative transmembrane domains. This gene showed loss or extreme decrease of expression in 6 of 10 uterine cancer-cell lines, 2 of 11 hepatic cell carcinoma-cell lines, 2 of 7 lung cancer-cell lines, 1 of 6 gastric cancer-cell lines, and 1 of 10 breast cancer-cell lines. (We named it DMHC ("down-regulated in multiple human cancers").) Our results suggest that loss of expression of DMHC at 17q25.1 may play an important role in development of variety of human cancers.

Amino Acid Sequence↗
PubMed2001

Association of allelic losses at 3p25.1, 13q12, or 17p13.3 with poor prognosis in breast cancers with lymph node metastasis.

To identify specific allelic losses that might correlate with postoperative mortality of patients with node-positive breast carcinomas, we examined tumors from a cohort of 263 such patients, who were followed clinically for 5 years postoperatively, for allelic losses among 18 microsatellite markers. Patients whose tumors had lost an allele at 3p25.1, 13q12, or 17p13.3 had significantly higher risks of mortality than those whose tumors retained both alleles at those loci. At 3p25.1, the 5-year mortality rate was 33.8% among patients with losses vs. 16.8% with retention (P = 0.0154); at 13q12, 30.3% vs. 13.0% (P = 0.0241); and at 17p13.3, 30.4% vs. 16.2% (P = 0.0243). Combined losses at 3p25.1 and 17p13.3 increased the predicted postoperative mortality risk by a factor of 4.9 (5-year mortality rate of 38.2% vs. 8.0%, P = 0.0006), and combined losses at 3p25.1 and 13q12 raised the predicted postoperative mortality risks by a factor of 2.9 (34.7% vs. 12.7%, P = 0.0441). These data indicate that loss of heterozygosity (LOH) at any one or a pair of loci at 3p25.1, 13q12, or 17p13.3 is a significant predictor of postoperative mortality for breast-cancer patients.

Adult↗
PubMed2001

Allelotyping of follicular thyroid carcinoma: frequent allelic losses in chromosome arms 7q, 11p, and 22q.

The genetic mechanisms involved in development of follicular thyroid carcinoma are poorly understood, although allelic losses (LOH) in this type of tumor have been reported in small panels of follicular thyroid carcinomas examined in earlier studies. To clarify the real frequency of allelic loss we carried out a genome-wide allelotyping study of 66 follicular thyroid carcinomas using 39 microsatellite markers representing all nonacrocentric autosomal arms. The mean frequency of LOH was 9.2%, and the mean fractional allelic loss was 0.09. The most frequent allelic losses were detected in 7q (28%), 11p (28%), and 22q (41%). When we compared these results with our previous allelotyping studies using identical markers in other types of thyroid cancers, the 9.2% mean frequency of allelic loss detected in follicular thyroid carcinomas was higher than that in papillary thyroid carcinomas (3%), but not as high as that detected in anaplastic thyroid carcinomas (20%). Frequent allelic losses of markers on chromosomes 7q, 11p, and 22q suggest locations to examine for the presence of suppressor genes associated with the development of follicular thyroid carcinoma.

Adenocarcinoma, Follicular↗
PubMed2001

Three aberrant splicing variants of the HMGIC gene transcribed in uterine leiomyomas.

Cytogenetic aberrations involving chromosome region 12q13-15 occur frequently among benign mesenchymal tumors in humans, e.g., pleomorphic adenomas of the parotid gland, pulmonary chondroid hamartomas, lipomas, or uterine leiomyomas. HMGIC, a gene encoding a protein of the high-mobility group, has been identified as a target of those events. Using the 3' rapid amplification of cDNA ends (RACE) technique, we identified six different fusion transcripts of the HMGIC gene among 13 uterine leiomyomas; three of these variants had not been described before. Radiation-hybrid mapping located all three of the novel fusion transcripts in the same chromosomal region as the HMGIC gene. Cloning of the entire HMGIC gene in a genomic contig of P1-derived artificial chromosomes and cosmids revealed that the 3' portion of each novel fusion transcript contained cryptic exonic sequences (designated a, b, and c) present in intron 3 of the HMGIC gene. Thus, aberrant alternative splicing was responsible for abnormal HMGIC isoforms in those myomas. Identification of these novel variants suggested that aberrant splicing can join chromosomal translocation and inversion as a mechanism for producing abnormal HMGIC transcripts, and that separation of the DNA binding domains of HMGIC from its acidic carboxyl-terminal regulatory domain can lead to development of benign mesenchymal tumors.

Alternative Splicing↗
PubMed2001

Allelic losses of loci at 3p25.1, 8p22, 13q12, 17p13.3, and 22q13 correlate with postoperative recurrence in breast cancer.

We previously defined 18 chromosomal regions in which frequent allelic losses were observed in breast cancers (T. Sato et al., Cancer RES:, 50: 7184-7189, 1990; Y. Harada et al., Cancer (PHILA:), 74: 2281-2286, 1994; I. Ito et al., BR: J. Cancer, 71: 438-441, 1995; K. Tsukamoto et al., Cancer (PHILA:), 78: 1929-1934, 1996; S. Matsumoto et al., Genes Chromosomes Cancer, 20: 268-274, 1997; T. Yokota et al., JPN: J. Cancer RES:, 88: 959-964, 1997; K. Tsukamoto et al., Cancer (PHILA:), 82: 317-322, 1998; A. Iida et al., Genes Chromosomes Cancer, 21: 108-112, 1998; K. Fukino et al., Genes Chromosomes Cancer, 24: 345-350, 1999; T. Yokota et al., Cancer (PHILA:), 85: 447-452, 1999; Y. Utada et al., JPN: J. Cancer RES:, 91: 293-300, 2000). To identify specific allelic losses that might correlate with postoperative recurrence, we examined tumors from a cohort of 504 breast cancer patients, who were followed clinically for 5 years postoperatively, for allelic losses of 18 microsatellite markers. Patients whose tumors had lost an allele at 3p25.1, 8p22, 13q12, 17p13.3, or 22q13 had significantly higher risks of recurrence than those whose tumors retained both alleles at those loci; at 3p25.1, the 5-year recurrence rate was 27% among patients with losses versus 18% with retention (P = 0.0131); at 8p22, 27% versus 14% (P = 0.0129); at 13q12, 28% versus 15% (P = 0.0109); at 17p13.3, 27% versus 20% (P = 0.0482); and at 22q13, 29% versus 20% (P = 0.0477). These data indicate that loss of heterozygosity at any one of these five specific loci is a significant predictor of postoperative recurrence among patients who have undergone surgery for breast cancer. These allelic losses can serve as negative prognostic indicators to guide postoperative management of patients.

Adult↗
PubMed2001

Overrepresentation of the EBAG9 gene at 8q23 associated with early-stage breast cancers.

EBAG9, an estrogen-responsive gene located at 8q23 was identified in an effort to clone CpG-binding sites. Its product was later found to be identical to RCAS1, a cancer cell-surface antigen implicated in immune escape. We determined the sequence of the complete cDNA and the genomic structure for EBAG9. EBAG9 gene copy number in 21% (27 of 129) primary breast cancers we examined; EBAG9 mRNA was consistently expressed in cancer cell lines. Detailed physical mapping of the 8q arm, including polymorphic markers for EBAG9 and the CMYC loci, revealed allelic gain of either EBAG9, CMYC, or both, in 45% (58 of 129) of the breast cancers we examined. The EBAG9 gene was increased exclusively in 16 of the 27 tumors showing gain at that locus; the other 11 showed gain of a larger chromosomal region containing both EBAG9 and CMYC. Analysis of subsequent series of 144 primary breast cancers for allelic gain at EBAG9 and CMYC locus showed a similar degree of gain at EBAG9, CMYC, or both. When a total of 273 breast cancers from two series were combined and analyzed for clinicopathological correlation, almost all of the tumors with EBAG9 increased but not those with CMYC. Twenty-eight of 29 were T1/T2 stage carcinomas (<5 cm in diameter), whereas one third (21 of 61) of the tumors in which CMYC was increased but EBAG9 was not, were advanced T3-stage tumors (P = 0.0012). These data suggest that EBAG9 and CMYC gene are independent targets of gain and that overrepresentation of EBAG9 may play a specific role in early stages of breast carcinogenesis.

Alleles↗
PubMed2000

Promoter analysis and chromosomal mapping of human EBAG9 gene.

The human EBAG9 was previously identified as an estrogen responsive gene using CpG-genomic binding site cloning (Watanate et al., (1998) Mol. Cell. Biol. 18: 442-449). Recently it was revealed that the EBAG9 is identical with RCAS1 which is a cancer cell surface antigen implicated in immune escape. Here, we isolated and analyzed the 5'-flanking region of human EBAG9 gene. We determined transcription initiation site, which has a homology with an initiator element YYCAYYYY, and found that TATA motif was absent. Deletion analysis of the 5'-flanking region using MCF-7 breast cancer cells indicated that the sequences -86 to -36 containing the ERE had the basal level of promoter activity and the upstream GC-rich region positively regulated the activity. EBAG9 promoter luciferase reporters containing the ERE could respond to estrogen, and electrophoretic mobility shift assay showed that ERalpha bound to the ERE. Moreover, fluorescent in situ hybridization analysis has shown that the human EBAG9 gene is located at chromosome 8q23 which is frequently amplified in tumors. These findings suggest that the human EBAG9 might be involved in carcinogenesis as an estrogen responsive gene.

Base Sequence↗
PubMed2000

Loss of heterozygosity at 3p24-p25 as a prognostic factor in breast cancer.

Differences in clinical course and biological characteristics among breast cancers will probably be explained ultimately by variations in the pattern of genetic alterations among the many genes that can play roles in carcinogenesis. Loss of heterozygosity (LOH) of a particular chromosomal region in a tumor, which presumably indicates loss of a growth-regulating 'tumor-suppressor' gene in that region, may represent a useful marker for postoperative prognosis. In earlier work we observed LOH at chromosomal regions 3p14-p21 and/or 3p24-p25 in a large proportion of breast cancers. To examine whether allelic losses in either of those regions might correlate with postoperative survival, we tested tumors from a cohort of 504 breast cancer patients for allelic losses of microsatellite markers in the relevant portions of chromosome 3p. Five years postoperatively, patients whose tumors had undergone LOH at 3p24-p25 were found to have borne significantly higher risks of mortality than women whose tumors retained both alleles at that locus; i.e. the 5-year mortality rate was 22% among patients with losses at 3p24-p25 vs. 9% with retentions of heterozygosity at that locus (P=0.0014). These data indicate that LOH at 3p24-p25 is a significant predictive factor for postoperative survival of patients who have undergone surgery for breast cancer.

Adult↗