Biomedical subjects

R Satodate

Publications and source records attributed to R Satodate.

At least 37 records · Page 2Linked to original sources

PubMed1997

Analysis of the fragile histidine triad gene in primary gastric carcinomas and gastric carcinoma cell lines.

The FHIT (fragile histidine triad) gene has been isolated from the chromosome region 3p14.2, which includes the fragile site locus FRA3B and the breakpoint of the t(3;8) of familial renal carcinoma. FHIT has been suggested to be a candidate tumor suppressor gene for digestive tract carcinomas. To evaluate the significance of FHIT gene abnormalities in gastric carcinogenesis, we examined the allelic status and transcripts of the gene in 23 primary gastric carcinomas as well as 7 gastric carcinoma cell lines. Four of the seven (57%) cell lines exhibited homozygous deletions of variable sizes at 3p14.2 all of which included D3S1300, which is located close to, or within, FRA3B. However, only 2 of 16 (13%) informative cases showed loss of heterozygosity at D3S1300 in the primary tumors. Direct analysis by reverse transcriptase polymerase chain reaction failed to reveal abnormal transcripts, including exon skipping and sequence changes, in the primary tumors or in the cell lines without homozygous deletions. These results suggest that FHIT gene abnormalities are infrequent in primary gastric carcinomas and that the frequent homozygous deletions seen in cell lines might simply reflect the plasticity of the genome at FRA3B under culture conditions.

Acid Anhydride Hydrolases↗

PubMed1996

Inactivation of the CDKN2 gene by homozygous deletion and de novo methylation is associated with advanced stage esophageal squamous cell carcinoma.

We examined the genomic status of the CDKN2 gene including de novo methylation of 5' CpG islands in primary and metastatic tumor samples from 31 patients with esophageal squamous cell carcinoma. One somatic frame shift mutation (1 of 31; 3.2%) was identified by PCR-single strand conformational polymorphism analysis and DNA sequencing. Homozygous deletion and de novo methylation of the gene were confirmed in 5 (16%) and 6 (19%) of 31 patients, respectively. Homozygous deletion and de novo methylation were significantly associated with silencing of gene expression (P < 0.01). Aberrations of the CDKN2 gene were detected in tumors with lymph node metastasis and muscular invasion (12 of 22; 54%) and in none of stage I tumors (0 of 9.0%; P < 0.05). These results suggest that homozygous deletion and de novo methylation are predominant mechanisms of inactivation of the CDKN2 gene and may be associated with metastatic and invasive phenotypes of esophageal squamous cell carcinoma.

Base Sequence↗

PubMed1996

Two distinct regions of deletion on the long arm of chromosome 5 in differentiated adenocarcinomas of the stomach.

Frequent loss of heterozygosity (LOH) on the long arm of chromosome 5 (5q) has been reported in many types of human malignancies, including gastric carcinoma. One of the targets of 5q-LOH in colorectal carcinoma is certainly the adenomatous polyposis coli (APC) gene on 5q21. However, other evidence has suggested the presence of another tumor suppressor gene in this region which may be inactivated in gastric carcinoma. In the present study, to determine the location of the putative tumor suppressor gene on 5q, LOH at nine microsatellite loci on 5q were investigated at 38 differentiated adenocarcinomas of the stomach that probably did not carry APC mutations. LOH at any locus on 5q occurred in 37% (14 of 38) of the tumors. Although many tumors exhibited large interstitial deletions on 5q that included the APC locus (5q21), we have identified minimum regions of deletion as the D5S428 locus and the interferon regulatory factor-1 (IRF-1) locus. Thus, at least two putative tumor suppressor genes, which play a crucial role in the genesis of differentiated adenocarcinoma of the stomach and are distinct from the APC gene, lie on 5q.

Adenocarcinoma↗

PubMed1996

Allelotype of adenoma and differentiated adenocarcinoma of the stomach.

The molecular mechanism of gastric tumourigenesis has not yet been clarified, although investigators have postulated that differentiated adenocarcinoma may arise from pre-existing adenoma, similarly to the colorectal adenoma-carcinoma sequence. An allelotype analysis has been performed to identify chromosomal regions which are frequently deleted in gastric tumours and to examine the significance of the adenoma-carcinoma sequence in gastric tumourigenesis. Forty-five gastric tumours, 20 adenomas, and 25 differentiated adenocarcinomas were examined for loss of heterozygosity (LOH) using 39 microsatellite markers covering each non-acrocentric chromosome arm. Frequent LOH in the adenocarcinomas was observed on chromosomes 2q (33 per cent), 4p (33 per cent), 5q (50 per cent), 6p (33 per cent), 7q (43 per cent), 11q (36 per cent), 14q (38 per cent), 17p (45 per cent), 18q (36 per cent), and 21q (40 per cent). In contrast, the incidence of LOH in adenomas did not exceed 10 per cent at any of the loci examined. In addition to the p53 gene on 17p and the DCC gene on 18q, which are known to be frequently deleted in differentiated adenocarcinomas of the stomach, other unknown tumour suppressor genes on the above-mentioned chromosomes may also be inactivated. These observations suggest that the adenoma-carcinoma sequence is not a major pathway in gastric tumourigenesis.

Adenocarcinoma↗

PubMed1996

Expression of cytokine genes and presence of enteroviral genomic RNA in endomyocardial biopsy tissues of myocarditis and dilated cardiomyopathy.

Viral infection, especially by enteroviruses, has been considered to be the most common cause of myocarditis, which may progress to dilated cardiomyopathy (DCM). Although the mechanism of progression remains uncertain, a cytokine-associated injury of myocytes has been proposed. Using reverse transcriptase polymerase chain reaction (RT-PCR), we examined the expression of interleukin 1 beta (IL-1 beta), IL-6, IL-8 and tumour necrosis factor alpha (TNF-alpha) and the presence of enteroviral genomic RNA in endomyocardial biopsy tissues obtained from patients with myocarditis and DCM. We examined endomyocardial biopsy tissues obtained from 6 patients with myocarditis, 21 with DCM and 15 with non-infectious cardiac diseases as controls. In patients with myocarditis, endomyocardial biopsy was performed twice at an interval of 1 month to 8 years after the onset of myocarditis. We used RT-PCR to detect IL-1 beta, IL-6, IL-8 and TNF-alpha genes expression and nested RT-PCR (nRT-PCR) to detect enteroviral genomic RNA. IL-1 beta, IL-6, IL-8 and TNF-alpha genes were expressed in 100% (6/6) and enteroviral genomic RNA in 67% (4/6) of myocarditis patients at the first biopsy. At the second biopsy, IL-1 beta, IL-6, IL-8 and TNF-alpha genes were expressed in none, 50% (3/6), 67% (4/6) and 67% (4/6), respectively, and enteroviral genomic RNA in 67% (4/6). Four patients with myocarditis, in whom IL-8 and TNF-alpha genes and enteroviral genomic RNA were detected, progressed to DCM at the second biopsy. IL-1 beta, IL-6, IL-8 and TNF-alpha genes were expressed in none, 24% (5/21), 38% (8/21), 57% (12/21) of DCM patients, respectively. Enteroviral genomic RNA was detected in 43% (9/21) of DCM. Neither cytokine expression nor enteroviral genomic RNA were detected in the controls. the high incidence of cytokines, especially IL-6, IL-8 and TNF-alpha, expression in myocarditis and DCM, which might be induced by enteroviral infection, suggests that cytokines play an important role in myocytic damage leading to DCM.

Adult↗

PubMed1996

Loss of heterozygosity at the DCC gene locus is not crucial for the acquisition of metastatic potential in oesophageal squamous cell carcinoma.

Tumour specimens from 111 patients with oesophageal squamous cell carcinoma were screened for loss of heterozygosity (LOH) at the deleted colorectal carcinoma (DCC) gene locus. DCC-LOH occurred in 10 of 61 informative cases (16%). No statistically significant correlation was observed between DCC-LOH and lymph node metastasis, histopathological grade or tumour stage. The survival of patients exhibiting DCC-LOH was not statistically different from that of patients without LOH. These results suggest that LOH at the DCC locus is not related to the acquisition of metastatic potential or the state of tumour cell differentiation in oesophageal squamous cell carcinoma.

Base Sequence↗

PubMed1996

Common deleted region on the long arm of chromosome 5 in esophageal carcinoma.

BACKGROUND & AIMS: The existence of an unknown tumor-suppressor gene on 5q for esophageal carcinoma other than the APC gene has been suggested. The location of the putative tumor-suppressor gene on 5q, distinct from the APC gene, was examined. METHODS: Sixty-one primary esophageal carcinomas were examined for nine microsatellite loci by the polymerase chain reaction followed by polyacrylamide gel electorophoresis. Loss of heterozygosity at the APC gene locus also was examined by the polymerase chain reaction-restriction fragment length polymorphisms. RESULTS: Thirty-five of 61 esophageal carcinomas (57%) showed loss of heterozygosity at single or multiple loci on 5q, and the smallest common deleted region was identified at 5q31.1, the location of the IRF-1 gene locus. All tumors showing loss of heterozygosity at the APC gene locus showed complete or large interstitial deletions on 5q. CONCLUSIONS: Deletion at the APC gene locus may just be the result of large deletions on 5q and may not be important in esophageal carcinogenesis, and the IRF-1 gene or other gene(s) on 5q31.1 may be the true target of frequent deletions on 5q that may play an important role in the pathogenesis of the majority of esophageal carcinomas.

Carcinoma↗

PubMed1996

Inactivation of the E-cadherin gene in primary gastric carcinomas and gastric carcinoma cell lines.

We investigated the E (epithelial)-cadherin gene for mutations and loss of heterozygosity (LOH) in 24 primary gastric carcinomas (12 differentiated and 12 undifferentiated types, including 3 signet-ring cell carcinomas), as well as 4 gastric carcinoma cell lines of the undifferentiated type (MKN-45, GCIY, HGC-27 and GT3TKB). We utilized PCR-SSCP and RT-PCR followed by direct sequencing to detect gene mutations and skipped exons, and RT-PCR-SSCP to examine LOH. In primary carcinomas, gene mutations or skipped exons were detected in 4 of 9 (44%) undifferentiated carcinomas of the scattered type, including 2 signet-ring cell carcinomas, and in none of the 3 undifferentiated carcinomas of the adherent type and 12 differentiated carcinomas. Demonstrated mutations of the E-cadherin gene included an 18 bp deletion (codon 418-423) and a 3 bp deletion (codon 400, calcium-binding domain), both located in exon 9. Skipping of exon 9 with a 1 bp insertion at codon 337, and skipping of exon 8 with a 1 bp deletion at codon 336, also were detected. LOH was confirmed in all of the carcinomas in which gene mutations or skipped exons (3/3 informative cases) were demonstrated. The MKN-45 cell line exhibited an 18 bp deletion at the exon 6-intron 6 boundary with loss of the wild-type allele, and 2 of the remaining 3 cell lines (HGC-27 and GT3TKB) had lost expression without detectable structural alteration of the E-cadherin gene. These data provide support for classic two-hit inactivation of the E-cadherin gene in a high percentage of undifferentiated carcinomas of the scattered type.

Alleles↗

PubMed1996

Simple method for quantifying disorientation of myofiber in endomyocardial biopsy specimens using an image analyzer.

The disarray of cardiac myofibers was morphometrically evaluated in biopsy specimens, obtained from patients with hypertrophic cardiomyopathy (HCM), hypertensive heart disease (HHD), chronic phase myocarditis and controls. Microphotographs of myocardium were taken at a final magnification of x 250. For each segment of myofibers, the longitudinal direction was traced on a transparent sheet, and the angle of the traced direction to the baseline was measured by an image analyzer. The standard deviation of the angles was used as an indicator of myofiber disarray. The histograms showed a narrow variation in the control group, but a wide variation in the patients with HCM, HHD and chronic phase myocarditis. The mean value of standard deviations of myofiber angles in HCM was significantly larger than that in the other groups. In HCM, the standard deviation of the myofiber angle proved to correlate positively with IVST/LVPWT (the thickness ratio of interventricular septum to the left ventricular posterior wall) (r = 0.70, p < 0.05), and also with LVEDP (left ventricular end-diastolic pressure) (r = 0.66, p < 0.05). In conclusion, the image analyzer serves as a simple and useful tool in quantifying the disorientation of myofibers and estimating the correlation between the histological and clinical findings.

Adult↗

PubMed1996

Association of myotonic dystrophy and sick sinus syndrome, with special reference to electrophysiological and histological examinations.

Sick sinus syndrome is a rare but potentially important cardiac disorder in patients with myotonic dystrophy. We evaluated 3 patients with myotonic dystrophy complicated with sick sinus syndrome using intracardiac electrocardiography and endomyocardial biopsy. Electrocardiography identified sinus arrest, atrial flutter and right bundle-branch block in 2 cases and marked sinus bradycardia and first-degree atrioventricular block in 1 case. Their sinus node recovery times were significantly prolonged as demonstrated by the overdrive suppression test. Two patients had Adams-Stokes syndrome and one had tachycardia with severe palpitations. Therefore permanent pacemaker implantation was indicated in all 3 cases. Light microscopic analysis of right ventricular endomyocardial biopsies showed vacuolar degeneration and nuclear deformity of cardiomyocytes in all cases and endocardial and interstitial fibrosis in 1 case. These findings indicate that pathological changes may occur in any part of the myocardium in patients with myotonic dystrophy.

Adult↗

PubMed1996

[Apoptosis in the process from viral myocarditis to dilated cardiomyopathy].

Detection of viral genomic RNAs in myocardium of dilated cardiomyopathy (DCM) suggested the relationship between DCM and viral myocarditis. The viral infection may cause cytokine expression followed by induction of inducible nitric oxide synthase (iNOS) and expression of Fas antigen. The iNOS has potent and long-lasting effects on NO generation, has cytotoxic effects and triggers apoptosis in car diomyocytes. In addition, the expression of Fas antigen directly induces apoptosis.

Apoptosis↗

PubMed1996

Angiomyolipoma arising in the colon.

Extrarenal angiomyolipomas are very rare. Here we report the first case of surgically resected angiomyolipoma of the descending colon that developed in a 50-yr-old man. The patient had no signs of or family history of tuberous sclerosis. He underwent a partial colectomy because the tumor obstructed the colon. Histologically, the tumor consisted of three components: mature fat cells, blood vessels, and smooth muscle cells, and was thereby diagnosed as an angiomyolipoma. Immunohistochemically, the proliferating smooth muscle cells were positive for vimentin, alpha-smooth muscle actin, and desmin. The tumor cells were negative for HMB-45, which is consistently expressed in renal angiomyolipomas.

Angiomyolipoma↗

PubMed1996

[Microsatellite analysis].

Microsatellites are tandem iterations of simple di-, tri-, or tetranucleotides. They are very useful for the analysis of LOH (loss of heterozygosity) because they are highly polymorphic and interspersed throughout the genome. The microsatellite analysis also allows us to investigate the genetic instability, demonstrated as the expansion or contraction of repeat elements (replication error, RER), which might have resulted from the disruption of mismatch repair genes such as hMSH2 and hMLH1. The microsatellite analysis is a novel tool of genetic analysis which provides valuable information in the field of molecular oncology.

Chromosome Deletion↗

PubMed1995

Microsatellite alterations in adenoma and differentiated adenocarcinoma of the stomach.

In order to elucidate the significance of the adenoma-carcinoma sequence in gastric carcinogenesis from a genetic point of view, we examined microsatellite alterations (replication error and loss of heterozygosity) on chromosomes 2p (D2S123), 3p (D3S1317), 5q (D5S409), 9p (IFNA), and 13q (D13S153) as well as p53 gene mutations in 13 adenomas and 23 differentiated adenocarcinomas including 8 early carcinomas of the stomach. Replication error was detected in only one of the adenomas (8%, 1/13) at the D5S409 locus and in none at the other loci, and loss of heterozygosity was also an infrequent event found in one adenoma (14%, 1/7 informative cases) at D5S409 and in none at the other loci. A p53 gene mutation was detected in one (8%, 1/13) of the adenomas. Thus, microsatellite alterations and p53 gene mutations are rare events in adenomas. In differentiated adenocarcinomas, replication error was detected in 4 (17%, 4/23) at single or multiple loci, and loss of heterozygosity was observed frequently at D3S1317 (25%, 3/12), D5S409 (67%, 6/9), and IFNA (26%, 5/19). Mutations in the p53 gene were detected in 9 (39%, 9/23) of the differentiated adenocarcinomas. Microsatellite alterations on several chromosomes and mutations in the p53 gene were frequent in differentiated adenocarcinomas, even those at an early stage. These results suggest that the adenoma-carcinoma sequence is relatively rare in gastric carcinogenesis, and that the majority of differentiated adenocarcinomas of the stomach may develop through a de novo pathway.

Adenocarcinoma↗

PubMed1995

Frequent microsatellite alterations on chromosome 3p in esophageal squamous cell carcinoma.

By the microsatellite assay, two types of genetic alterations, loss of heterozygosity (LOH) and replication error (RER), were examined using 7 dinucleotide repeat markers [D3S1317 (3p26); CI3-1169 (3p25); CI3-946 (3p25); D3S1255 (3p24.2-25); CI3-771 (3p21.3); CI3-1413 (3p14.1-14.3); and CI3-373 (3p13)] on the short arm of chromosome 3p as well as 3 markers [D2S123 (2p15-16), IFNA (9p22), and D16S408 (16q12.1-13)] on other chromosomes in 35 patients with esophageal squamous cell carcinoma. On 3p, LOH was detected in 34% (12 of 35) and RER was detected in 60% (21 of 35) at single or multiple loci. RER occurred at a similar frequency in all stages and did not correlate with clinicopathological characteristics. On the other hand, LOH at the 3p25 locus was more frequently detected in carcinomas with lymph node metastasis than in those without it (P < 0.05). The incidences of microsatellite alterations were low on the chromosomes other than 3p, except at D2S123, where the incidence of RER was 20%. These findings suggest that RER on 3p is an early event and that a tumor suppressor gene which is involved in the progression of esophageal squamous cell carcinoma may exist near the 3p25 locus.

Base Sequence↗

PubMed1995

The sequential accumulation of genetic alterations characteristic of the colorectal adenoma-carcinoma sequence does not occur between gastric adenoma and adenocarcinoma.

We screened 30 gastric adenomas and 72 gastric adenocarcinomas for four genetic alterations (mutations of the K-ras, APC, and p53 genes and loss of heterozygosity at the DCC genetic locus) which are known to occur during colorectal tumourigenesis. We used polymerase chain reaction (PCR) single-strand conformation polymorphism analysis to detect mutations. Loss of heterozygosity (LOH) at the DCC locus was ascertained directly by performing PCR on the variable number of tandem repeats within the gene. Mutations of the K-ras gene were not detected in any gastric adenoma or carcinoma. APC mutations were detected in 20 per cent (6/30) of the adenomas but in only 1.4 per cent (1/72) of the carcinomas. In contrast, the p53 gene was frequently mutated in carcinomas (35 per cent; 25/72), but not in adenomas. LOH at the DCC locus was a frequent occurrence in carcinomas (58 per cent; 11/19 informative cases) but was infrequent in adenomas (14 per cent; 1/7). Alterations of the p53 and DCC genes occurred frequently both in differentiated and in undifferentiated gastric carcinomas. The considerable differences in the incidences of genetic alterations between gastric adenoma and carcinoma indicate that the sequential development of gastric carcinoma from adenoma is uncommon in gastric carcinogenesis.

Adenocarcinoma↗

PubMed1995

Epithelial-cadherin gene is not mutated in ductal carcinomas of the breast.

We investigated mutations of the epithelial (E)-cadherin gene and loss of heterozygosity (LOH) at flanking loci using three microsatellite markers on the long arm of chromosome 16 in 25 ductal carcinomas of the breast. Expression of E-cadherin was also investigated immunohistochemically. No mutations were detected in exons 6 through 9 of the E-cadherin gene. LOH was observed more frequently (42%) at D16S402 (16q-ter) than at D16S421 (16q22.3-q23.1) (17%), which is located near the E-cadherin gene. Expression of E-cadherin was observed at the cell borders in 92% (11/12) of the tumors examined. The absence of mutations in the E-cadherin gene and its conserved expression suggest that inactivation of E-cadherin does not contribute significantly to the invasion or metastatic potential of ductal carcinomas of the breast. Furthermore, the high frequency of LOH at 16q-ter suggests the existence of another tumor suppressor gene which may play a crucial role in the genesis of ductal carcinomas of the breast.

Adenocarcinoma, Scirrhous↗

PubMed1995

Loss of heterozygosity on the short arm of chromosome 9 without p16 gene mutation in gastric carcinomas.

A putative tumor suppressor gene, p16 (MST1; multiple tumor suppressor 1/CDK4I; cyclin-dependent kinase 4 inhibitor), was isolated and mapped on the short arm of chromosome 9 (9p). The significance of p16 mutations in gastric tumorigenesis was examined by assessing p16 mutations as well as loss of heterozygosity (LOH) on 9p in 13 gastric adenomas and 45 adenocarcinomas. LOH on 9p (IFNA; alpha-interferon locus) was detected in 22% (5/23 informative cases) of differentiated adenocarcinomas, 10% (1/10) of undifferentiated carcinomas and none (0/6) of the adenomas. Although we found a sequence polymorphism at the second position of codon 99 (CGC/CAC) of the p16 in one gastric adenoma patient, no somatic mutations were detected in any of the gastric adenomas or adenocarcinomas. These results suggest that p16 mutations probably do not contribute to gastric tumorigenesis. However, these data suggest that another tumor suppressor gene on 9p (near the IFNA locus) may contribute to the progression of differentiated adenocarcinoma of the stomach.

Adenocarcinoma↗