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N Matsubara

Publications and source records attributed to N Matsubara.

At least 19 recordsLinked to original sources

Oesophageal squamous cell carcinoma may develop within a background of accumulating DNA methylation in normal and dysplastic mucosa.

BACKGROUND: Oesophageal squamous cell carcinoma (OSCC) often arises from preceding dysplastic lesions in the oesophageal epithelium. However, the molecular changes occurring in premalignant lesions are not well understood. An epigenetic change is an example of OSCC that may occur within the epithelium. AIM: To investigate the methylation status of multiple promoters in cancer-derived DNA, as well as in the background epithelium of OSCC, including dysplastic lesions and non-neoplastic mucosa. The normal epithelium from patients without cancer was also examined. The findings were correlated with the mutational status of p53. PATIENTS AND METHODS: 56 patients with advanced OSCC, 21 patients with intraepithelial neoplasia (IEN), 56 patients with a background of non-neoplastic epithelium, adjacent to the OSCC, and 42 normal control epithelia from healthy volunteers were studied. The promoter methylation status of SFRP1, SFRP2, DCC, APC, p16(INK4a), p14(ARF), MINT1, MINT2, MINT31, CACNA1G, COX2, DAPK, hMLH1 and MGMT was examined by methylation-specific single polymerase chain reaction or combined bisulphite restriction analysis. The mutation of p53 by direct sequencing was assessed. RESULTS: DNA methylation was observed in OSCC and in its background epithelium. The frequency of CpG island methylation increased from a baseline level in the background non-neoplastic epithelium, through IEN, to advanced OSCC. However, mutations in p53 were almost exclusively observed in IEN and OSCC. More extensive DNA methylation was seen in the neoplastic lesions (OSCC or IEN) having a p53 mutation than in those with wild-type p53. CONCLUSION: DNA methylation is present at low levels in the non-neoplastic oesophageal epithelium and appears to contribute to the progression of the dysplasia-carcinoma sequence in OSCC carcinogenesis.

Adult↗

Prevention of inflammation-mediated acquisition of metastatic properties of benign mouse fibrosarcoma cells by administration of an orally available superoxide dismutase.

Weakly tumorigenic and nonmetastatic QR-32 cells derived from a fibrosarcoma in C57BL6 mouse are converted to malignant cells once they have grown after being coimplanted with a gelatine sponge which induces inflammation. We administered a newly developed peroral superoxide dismutase (SOD), oxykine, and as control vehicle, gliadin and saline, starting 2 days before the coimplantation and continued daily throughout the experiment. In the oxykine group, tumour incidence was lower (41%) than in the gliadin or saline group (83 and 79%, respectively). The inhibitory effect of oxykine was lost when an individual component of oxykine was administered, that is, SOD alone and gliadin alone. The effect was also abolished when administered by intraperitoneal route. When perfused in situ with nitroblue tetrazolium, an indicator of superoxide formation, the tumour masses from gliadin and saline groups displayed intense formazan deposition, whereas, those from oxykine group had less deposition. Enzymatic activity of SOD was also increased in oxykine group. Arising tumour cells in gliadin and saline groups acquired metastatic phenotype, but those in oxykine group showed reduced metastatic ability. These results suggested that the orally active SOD derivative prevented tumour progression promoted by inflammation, which is thought to be through scavenging inflammatory cell-derived superoxide anion.

Administration, Oral↗

Cell preparation of Enterococcus faecalis strain EC-12 prevents vancomycin-resistant enterococci colonization in the cecum of newly hatched chicks.

The use of antimicrobials in broilers is considered to be a cause of the appearance of vancomycin-resistant enterococci (VRE). Once VRE penetration occurs, whatever its origin, it is difficult to expel the enterococci from the intestine because of their multiple resistance, whether natural or acquired. In this study, we evaluated the prevention of VRE colonization by the dietary supplementation of a cell-wall preparation of Enterococcus faecalis strain EC-12 (EC-12) in newly hatched broilers that were challenged by experimental infection with VRE. The chicks were fed a basal diet supplemented with 0.05% (wt/wt) EC-12 powder for 15 d. The control group and that administered Lactobacillus sp. were fed the basal diet. The VRE challenge was administered orally when the chicks were 2 d old (d 0). Dietary EC-12 reduced VRE colonization in the intestine from d 3 to 14. Total IgA in the cecal digesta and total IgG in the serum were higher on d 14 in the EC-12 treatment group. However, VRE-specific and EC-12-specific antibodies were not affected in serum. Hence, it appeared that dietary EC-12 stimulated the gut immune system and reinforced the immune reaction against the VRE challenge to accelerate its defecation from the chick intestine.

Animals↗

Optic nerve and spinal cord manifestations of malignant atrophic papulosis (Degos disease).

A fatal case of malignant atrophic papulosis (Degos disease) with optic nerve and spinal cord involvement is described. Magnetic resonance imaging (MRI) of the optic nerve showed abnormal signal enhancement on fat suppressed T1 weighted images after intravenous meglumine gadopentetate infusion. On T2 weighted sagittal images, a sawtooth pattern was observed over seven vertebral segments of the spinal cord. On necropsy, a severe loss of myelinated nerve fibres in the left optic nerve was seen, with thrombotic obstruction of the central retinal artery. Spongy degeneration was observed in all levels of the spinal cord, with patchy and motheaten patterns caused by thromboses and endothelial proliferation in subarachnoid vessels. Findings on MRI were consistent with findings on pathological examination.

Atrophy↗

Dynamic gadolinium-enhanced fat-suppressed T1-weighted MRI (chemical shift selective images) for remitting seronegative symmetrical synovitis with pitting edema.

A 75-year-old man suddenly suffered from polyarthralgia and pitting edema in his distal extremities. Laboratory tests revealed inflammation, negative rheumatoid factor, and positive B7 human leukocyte antigen typing. Severe synovitis was observed in dynamic gadolinium-enhanced fat-suppressed (DGEFS) T1-weighted images of his right hand. Our diagnosis was remitting seronegative symmetrical synovitis with pitting edema (RS(3)PE syndrome). He responded dramatically to low-dose corticosteroids, after which his synovitis remarkably improved as observed with DGEFS imaging. DGEFS imaging is useful for distribution of synovitis in patients with RS(3)PE syndrome as well as assessing the efficacy of treatment.

Aged↗

Deletion analysis of the sapovirus VP1 gene for the assembly of virus-like particles.

Human sapovirus (SaV) strains are agents of gastroenteritis. They cannot be grown in cell culture. In this study, constructs containing SaV N- and C-terminal-deleted recombinant capsid proteins (rVP1) were expressed in a baculovirus expression system to allow us to better understand the sequence requirements for the formation of virus-like particles (VLPs). Only proteins derived from N-terminal-deleted rVP1 constructs that began 49 nucleotides downstream assembled into VLPs, which included both small and native-size VLPs. Our results were similar to those reported in a rabbit hemorrhagic disease virus (RHDV) N- and C-terminal-deleted rVP1 expression study but were distinct from those reported in a norovirus N- and C-terminal-deleted rVP1 expression study, suggesting that SaV and RHDV may have similar expression requirements.

Baculoviridae↗

BRAF mutation is associated with DNA methylation in serrated polyps and cancers of the colorectum.

BACKGROUND AND AIMS: Mutations in BRAF have been linked with colorectal cancers (CRC) showing high level microsatellite instability (MSI-H). However, the distribution of BRAF mutations in MSI-H cancers remains to be clarified with respect to precursor lesions and the CpG island methylator phenotype (CIMP). METHODS: Forty three hyperplastic polyps (HP), nine mixed polyps (MP), five serrated adenomas (SA), 28 conventional adenomas (AD), 18 hereditary non-polyposis colorectal cancers (HNPCC), and 127 sporadic CRC (46 MSI-H and 81 non-MSI-H) were collected from patients undergoing colectomy for either CRC or hyperplastic polyposis. Twenty five of 57 serrated lesions were derived from four patients with hyperplastic polyposis. HP were further subdivided according to recently documented morphological criteria into 27 classical HP and 16 variant lesions described as "sessile serrated adenoma" (SSA). All tumours were screened for BRAF activating mutations. RESULTS: The BRAF mutation was more frequent in SSA (75%) and MP (89%) than in classical HP (19%), SA (20%), and AD (0%) (p<0.0001), and also in sporadic MSI-H cancers (76%) compared with HNPCC (0%) and sporadic non-MSI-H cancers (9%) (p<0.0001). The BRAF mutation was identified more often in CIMP-high serrated polyps (72%) and CIMP-high CRC (77%) than in CIMP-low (30%) and CIMP-negative (13%) polyps (p = 0.002) as well as CIMP-low (18%) and CIMP-negative (0%) CRC (p<0.0001). CONCLUSIONS: The BRAF mutation was frequently seen in SSA and in sporadic MSI-H CRC, both of which were associated with DNA methylation. Sporadic MSI-H cancers may originate in SSA and not adenomas, and BRAF mutation and DNA methylation are early events in this "serrated" pathway.

Adenoma↗

Allelic imbalance and microsatellite instability in plasma DNA released from polyclonal pancreatic adenocarcinoma.

Evidence of circulating soluble DNA in blood-stream of cancer patients has emerged. Because the plasma DNA is largely derived from cancer cells, genetic analysis of plasma DNA is important to understand the molecular events occurred in cancer patient. Seven microsatellite markers in the soluble plasma DNA from patients with pancreatic adenocarcinoma and other pancreato-biliary malignant tumors were examined for microsatellite instability (MSI) and allelic imbalance (AI). A variety of genetic alterations including MSI and AI were detected in the plasma DNA. Some alterations were detected before recurrence of the tumor was verified. Analysis of five primary pancreatic adenocarcinomas by microdissection revealed that the heterogeneous nature of pancreatic tumors is associated with both MSI and AI in the same tumor. The presence of altered plasma DNA including MSI and/or AI from the same pancreatic cancer patient may be important evidence for the presence of these alterations in heterogeneous primary tumors. Analysis of plasma DNA could become one of the diagnostic or therapeutic measures for this type of pancreatic adenocarcinoma.

Aged↗

E2F-4 mutation in hereditary non-polyposis colorectal cancer.

Defects in the DNA mismatch repair function are known to cause microsatellite instability (MSI) in hereditary non-polyposis colorectal cancer (HNPCC) as well as in a subset of sporadic colorectal cancer (CRC). We previously reported that the E2F-4 gene, which encodes an important transcription factor in cell cycle control, had frequent tumor-specific mutations at a coding region of trinucleotide microsatellite (CAG)n in a subset of human sporadic CRC with high-frequency MSI (MSI-H). In this study, we assessed mutations of E2F-4 in HNPCC as well as other target genes of defective DNA mismatch repair function. Eighteen colorectal cancer (CRC) patients from 13 kindreds meeting the Amsterdam criteria for HNPCC were analyzed and compared to sporadic CRC patients with MSI-H. We detected mutations of E2F-4 at the same repeat sequence in HNPCC. The frequency of the E2F-4 mutation in HNPCC was comparable with that in sporadic CRC with MSI-H. E2F-4 was considered to be one of the important target genes responsible for the carcinogenesis of HNPCC.

Base Pair Mismatch↗

Genetic alterations of the ornithine decarboxylase gene in human colorectal cancers.

Ornithine decarboxylase (ODC), a critical regulatory enzyme for polyamine biosynthesis, is strictly regulated in human cells. Several studies suggested the importance of elevated enzymatic activity and altered biochemical characteristics of ODC in malignant cells. Because mutation of ODC in primary human hepatocellular carcinoma has been reported, we examined whether the genetic alterations, such as mutations or structural alterations of the gene, also account for the alteration of ODC activity in human colorectal cancer. No mutation or structural alteration in the ODC was detected in any of the colorectal tumors and normal tissues examined. These results suggest that a mutation or structural alteration of the ODC may not be involved in human colorectal carcinogenesis.

Blotting, Southern↗

Combination of tumor necrosis factor alpha and interferon alpha induces apoptotic cell death through a c-myc-dependent pathway in p53 mutant H226br non-small-cell lung cancer cell line.

We investigated the role of wild-type p53 and c-myc activity in apoptosis induced by a combination of natural human tumor necrosis factor alpha (TNF-alpha) and natural human interferon alpha (IFN-alpha). Studies were performed with two human non-small-cell lung cancer cell lines, H226b, which has wild-type p53, and H226br, which has a mutant p53. The combination of IFN-alpha and TNF-alpha significantly inhibited cell growth and induced apoptotic cell death of both H226b and H226br, compared with IFN-alpha or TNF-alpha alone. Treatment with one or both cytokines did not affect the expression level of p53 in both cell lines. These results suggest that the combination of IFN-alpha/TNF-alpha induces apoptotic cell death through a p53- independent pathway. The c-myc oncogene is known to be involved in apoptosis induced by TNF. Antisense c-myc oligonucleotides have been reported to modulate cell growth or apoptosis in several cell lines. Antisense oligodeoxynucleotides were added to the culture of H226br cells before the addition of IFN-alpha/TNF-alpha. Antisense c-myc inhibited IFN-alpha/TNF-alpha cytotoxicity and apoptotic cell death. In conclusion, this study provides support for the speculation that TNF-alpha/IFN-alpha induce apoptosis through a c-myc-dependent pathway rather than a p53-dependent pathway. (c)2001 Elsevier Science.

Antineoplastic Combined Chemotherapy Protocols↗

High frequency of low-level microsatellite instability in early colorectal cancer.

Molecular events in early colorectal cancers (CRCs) have not been well elucidated because of the low incidence of early CRCs in clinical practice. Therefore, we studied 104 sporadic early CRCs with invasion limited to submucosa compared with 116 advanced CRCs. Loss of heterozygosity as well as microsatellite instability (MSI) status was examined. A significantly high frequency of low-level MSI (MSI-L) phenotype was detected in early CRCs (51.0%) compared with advanced CRCs (25.9%; P = 0.0001). In early and advanced CRCs, samples with MSI-L phenotype differed from microsatellite stable (MSS) phenotype with respect to loss of heterozygosity at 1p32 and 8p12-22. MSI-L is a frequent genetic event in early CRCs and may be a novel pathway in colorectal carcinogenesis distinct from both MSI-H and MSS.

Aged↗

Genetic alterations of candidate tumor suppressor ING1 in human esophageal squamous cell cancer.

Overexpression of ING1, a candidate tumor suppressor gene, efficiently blocks cell growth or induces apoptosis in different experimental systems. ING1 maps to chromosome 13q33-34, and because loss of the terminal region of chromosome 13q has been implicated in esophageal squamous cell cancer (ESCC), we examined ESCC for genetic alterations of ING1. Among 31 informative cases of ESCC, 58.9% of the tumors showed allelic loss at chromosome 13q33-34, and we detected four tumor-specific missense nucleotide changes. These alterations were found within the PHD finger domain and nuclear localization motif of the ING1 and may be functionally involved in the development of ESCC. Because immunohistochemical study revealed that all of the ESCC samples showed loss of ING1 protein expression, genetic or epigenetic alterations that abrogate the normal function of ING1 may contribute to esophageal squamous cell carcinogenesis.

Aged↗

Sweeping on a microchip: concentration profiles of the focused zone in micellar electrokinetic chromatography.

On-line sample concentration by sweeping was investigated in microchip micellar electrokinetic chromatography (MEKC), By changing the distance between the injection cross and the detection points, the profile of the concentration process and the diffusion process in sweeping was elucidated. Rhodamine B injected for 4 s was best concentrated by sweeping at 9.4 mm from the injection cross and the enhancement factor was 450. At the longer distance from this point the peak of Rhodamine B was broadened and diluted by diffusion. The diffusion constant of Rhodamine B calculated from the experiment was 5.7 x 10(-6) cm2s(-1). The mixture of rhodamine B, sulforhodamine B, and cresyl fast violet was concentrated by sweeping and separated by MEKC at the same time.

Chromatography, Micellar Electrokinetic Capillary↗

Effect of naturally occurring E2F-4 alterations on transcriptional activation and proliferation in transfected cells.

E2F is a family of transcription factors implicated in the regulation of gene expression required for progression through the G(1)-S transition. We have previously detected tumor-specific mutations at a trinucleotide repeat coding sequence of E2F-4 gene in a subset of human sporadic colorectal cancers. The purpose of this study was to investigate the potential functional consequences of these E2F-4 mutations. We transfected NIH3T3 fibroblasts with expression constructs containing wild-type as well as mutant E2F-4 cDNA, and the effect of the E2F-4 mutations on proliferation was examined. Alteration in transactivation of the E2F consensus promoter sequence was also examined by transient cotransfection of a E2F-4 with a DP-2 construct into cultured human cells. Transfected cell clones overexpressing mutant E2F-4 grew more rapidly and showed higher proliferative activity by increased immunohistochemical staining for proliferating cell nuclear antigen (PCNA). All three mutant forms of E2F-4 showed elevated transactivation of the E2F consensus promoter sequence. Thus, expression of mutant E2F-4s confers a growth advantage in vivo, and this effect may be related to the acquisition of a neoplastic phenotype.

3T3 Cells↗

Ulnar bursa distention following volar subluxation of the distal radioulnar joint after distal radial fracture: a rare cause of carpal tunnel syndrome.

This report describes an eighty-four-year-old woman with persistent carpal tunnel syndrome attributable to an ulnar bursa distention associated with the subluxation of the distal radioulnar joint after distal radial fracture. During surgery, when the forearm was placed in supination, the ulna head with a sharp osteophyte was found to be displaced into the carpal tunnel through a defect of the ruptured capsule of the wrist joint. This volar subluxation of the ulnar head had caused distention of the ulnar bursa, causing compression of the median nerve, which resulted in carpal tunnel syndrome. In addition to reduce displaced fractured segment to obtain anatomic articular surface, original radial length and tilt, the anatomic restoration of the distal radioulnar joint is essential to maintain better long-term function after fracture of the distal radius.

Accidental Falls↗

The relation between plasma homocysteine concentration and methylenetetrahydrofolate reductase gene polymorphism in pregnant women.

OBJECTIVE: Our purpose was to clarify the influence of methylenetetrahydrofolate reductase (MTHFR) gene polymorphism on plasma homocysteine (Hcy) concentrations during early pregnancy. METHODS: Between 1996 and 1998, Hcy concentration and MTHFR gene polymorphism were studied in 840 pregnant women between 6 to 12 weeks' gestation. Hcy concentration was measured by amino acid autoanalyzer (DLC-300, Nihon Denshi), and MTHFR genotypes were determined by the PCR/RFLP methods. Pregnancy outcomes were compared in association with Hcy concentration and MTHFR genotypes. RESULTS: A total of 816 of the 840 women were enrolled into the study because MTHFR genotypes were not available in 24 women. Genotypes of C677T in the MTHFR gene were CC: CT: TT (%) = 280 (34.3): 400 (49.0): 136 (16.7). Plasma Hcy concentration was significantly (p < 0.0001) higher in women with TT genotype than other genotypes [CC: CT: TT = 5.67 (2.8-10.6): 5.80 (2.5-20.1): 6.91 (3.5-20.9) nmol/ml, median (range)]. Women with hyperhomocysteinemia had severe preeclampsia (2 of 35 vs 5 of 714, p < 0.01) and stillbirth (2 of 35 vs 10 of 714, p < 0.05) more frequently than normohomocysteinemia. CONCLUSIONS: Plasma Hcy concentration during early pregnancy was higher in women with homozygote for the T677 allele in the MTHFR gene than other genotypes.

Adult↗

Microsatellite instability correlates with normal expression of cyclin E in hepatocellular carcinomas.

It has been reported that microsatellite instability (MSI) strongly correlates with carcinogenesis and cancer progression. In the present study, we studied the incidence of MSI at 5 polymorphic microsatellite markers (D5S406, D13S153, D16S402, D17S796, and poly(A) tract BAT26), the expression of G1 cyclins (cyclin A, cyclin D and cyclin E), and Ki-67 labeling index in 30 surgically resected hepatocellular carcinomas (HCCs) and their adjacent non-cancerous tissues. The results of analysis showed that 43% of HCCs exhibited MSI in one locus, 10% in two loci, and 3% in three loci. Overexpressions of cyclin E and cyclin A were observed in 57% and 83% of HCCs, respectively. MSI in HCCs, however, correlated with normal expressions of cyclin E and cyclin A and with a low labeling index of Ki-67. Thus, patients with HCCs exhibiting MSI at these 5 markers may have less involvement of G1/S disregulation and may have better prognosis than other patients with HCC.

Aged↗