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Kokichi Sugano

Publications and source records attributed to Kokichi Sugano.

At least 19 recordsLinked to original sources
PubMed2026

Hereditary Diffuse Gastric Cancer With Poorly Differentiated Gallbladder Adenocarcinoma: A Case Report Suggesting Carcinogenesis in the Stomach and Gallbladder Caused by a Pathogenic Germline Variant in CDH1.

BACKGROUND/AIM: Hereditary diffuse gastric cancer (HDGC) is an autosomal dominant cancer syndrome primarily characterized by a high lifetime risk of diffuse gastric cancer and lobular breast cancer. It is predominantly caused by inactivating germline variants in the tumor suppressor gene CDH1. While the association between HDGC and these two specific malignancies is well-established, the co-occurrence of extra-gastric malignancies in other organs remains exceptionally rare. In particular, the clinical and genetic relationship between HDGC and gallbladder adenocarcinoma has not been previously clarified. CASE REPORT: We present the case of a 67-year-old female initially referred for surgical management of gallbladder cancer (GBC) following an initial cholecystectomy for progressive wall thickening. Pathological examination of the gallbladder revealed a de novo, poorly differentiated adenocarcinoma invading the subserosal layer with reduced E-cadherin expression. Given the atypical histopathology and a significant family history-her father and brother both died of gastric cancer at young ages-a preoperative gastric endoscopy was performed. The endoscopy identified multiple faded mucosal lesions, which biopsy confirmed as signet-ring cell carcinoma. The patient subsequently underwent total gastrectomy and gallbladder bed resection. Postoperative pathology identified 22 distinct malignant gastric lesions, predominantly signet-ring cell carcinoma (pT1a), showing variable or lost E-cadherin expression. Germline genetic testing via direct sequencing identified a pathogenic frameshift mutation in exon 5 of the CDH1 gene. CONCLUSION: This represents the first reported case of synchronous HDGC and primary gallbladder adenocarcinoma associated with a germline CDH1 mutation. Our findings suggest that pathogenic CDH1 variants may contribute to the carcinogenesis of poorly differentiated gallbladder adenocarcinoma. Clinicians should consider the possibility of extra-gastric malignancies in HDGC patients.

Humans↗
PubMed2004

High resolution for single-strand conformation polymorphism analysis by capillary electrophoresis.

Since the successful completion of the Human Genome Project, increasing concern is being directed toward the polymorphic aspect of the genome and its clinical relevance. A form of single-strand DNA-conformation polymorphism analysis (SSCP) employing nondenaturing slab-gel electrophoresis (SGE) is applicable to the genetic diagnosis of bladder cancer from urine samples. To bring this technique into routine clinical practice, the use of capillary electrophoresis (CE) is naturally favorable in terms of speed and automation. However, the resolving power of SSCP, a prerequisite basis for reliability required in diagnostics, remains as a challenge for CE systems. We thus focused on this topic and conducted studies on CE instruments equipped with a single capillary or an array of multiple capillaries, using the resolution (Rs) as a quantitative scale for the resolving power. Polymer concentration and buffer are shown to be the decisive parameters. High Rs values of >2.5 are achieved for representative SNPs markers under the optimized conditions, without sacrificing such intrinsic advantages of CE over SGE as the 10-fold quicker migration time and operation that is reproducible, continuous, and automatic. The strategies presented broaden the limits of CE in both the current and related applications.

Buffers↗
PubMed2004

Detection of allelic imbalance in the gene expression of hMSH2 or RB1 in lymphocytes from pedigrees of hereditary, nonpolyposis, colorectal cancer and retinoblastoma by an RNA difference plot.

A number of phenotypes in hereditary disorders or common diseases are associated with specific genotypes. However, little is known about the molecular basis of phenotypic variation among individuals carrying the same mutation or polymorphism. Here, a highly quantitative approach was taken to examine a relative amount of mRNA from two polymorphic alleles with a coefficient of variation of less than 10% using an RNA difference plot (RDP). RDP analysis revealed that most genes examined were expressed in equal amount from the two alleles in normal lymphocytes. In contrast, the relative amounts of hMSH2 or RB1 mRNAs carrying premature termination codons were significantly reduced compared with those of wild-type mRNAs in lymphocytes from carriers of hereditary, nonpolyposis, colorectal cancer and hereditary retinoblastoma. The balance of allelic expression of the RB1 was also significantly impaired in a pedigree of retinoblastoma carrying a missense mutation in codon 661. The relative expression of the mutant to the wild-type RB1 alleles among the carriers varied from 0.40 to 2.39. The analysis of the expression diversity of a disease-associated allele by RDP could provide a novel approach to elucidating the mechanisms underlying phenotypic variation among individuals carrying an identical mutation or polymorphism at a single locus.

Alleles↗
PubMed2004

Psychologic distress after disclosure of genetic test results regarding hereditary nonpolyposis colorectal carcinoma.

BACKGROUND: To the authors' knowledge, there have been few studies of the psychologic distress after disclosure of genetic test results for hereditary nonpolyposis colorectal carcinoma (HNPCC). The objectives of this study were to identify the prevalence rates and predictors of psychologic distress and to evaluate the feelings of guilt after disclosure of the test results in Japanese probands and unaffected relatives. METHODS: Probands and unaffected relatives were interviewed immediately after the first genetic counseling session for HNPCC and again 1 month after disclosure of the genetic test results. The prevalence of major and minor depression, acute stress disorder (ASD), posttraumatic stress disorder (PTSD), and posttraumatic stress symptoms (PTSS) were assessed using the Structured Clinical Interview based on the Diagnostic and Statistical Manual of Mental Disorders, 3rd edition revised (DSM-III-R) or the DSM-IV; feelings of guilt were investigated using a numeric scale and a semistructured interview. RESULTS: Among 47 participants who completed the baseline interview, 42 participants (89%) completed the 1-month follow-up interview. Although none of the participants met the criteria for major depression, ASD, or PTSD at the follow-up interview, 3 of 42 participants (7%) met the criteria for minor depression and 2 participants (5%) had PTSS. The only predictor of psychologic distress found was the presence of a history of major or minor depression (odds ratio, 19.41; 95% confidence interval, 1.42-264.95; P < 0.05). Five of 42 participants (12%) had feelings of guilt. CONCLUSIONS: Disclosure of genetic test results for HNPCC may not cause significant psychologic distress in Japanese probands or relatives. However, healthcare providers should not neglect to assess these individuals for psychologic responses, such as minor depression and PTSS.

Adult↗
PubMed2004

Three-dimensional microarray compared with PCR-single-strand conformation polymorphism analysis/DNA sequencing for mutation analysis of K-ras codons 12 and 13.

BACKGROUND: We developed a rapid, precise, and accurate microarray-based method that uses a three-dimensional platform for detection of mutations. METHODS: We used the PamChip microarray to detect mutations in codons 12 and 13 of K-ras in 15 cell lines and 81 gastric or colorectal cancer tissues. Fluorescein isothiocyanate-labeled PCR products were analyzed with the microarray. We confirmed the microarray results with PCR-single-strand conformation polymorphism (SSCP) analysis and DNA sequencing. RESULTS: We could correctly identify wild-type, heterozygous, and homozygous mutant genotypes with the PamChip microarray in <3.5 h. The array data were consistent with those of PCR-SSCP analysis and DNA sequencing. All 15 cell lines and 80 of 81 clinical cancer specimens (98.8%; 95% confidence interval, 96.4-100%) were genotyped accurately with the microarray, a rate better than that of direct DNA sequencing (38.9%) or SSCP (93.8%). Only one clinical specimen was misdiagnosed as homozygous for the wild-type allele. Densitometric analysis of SSCP bands indicated that the content of the mutant allele in the specimen was approximately 16%. The PamChip microarray could detect mutant alleles representing more than 25% of the SSCP band proportions. Therefore, the limit for detection of mutant alleles by the PamChip microarray was estimated to be 16-25% of the total DNA. CONCLUSIONS: The PamChip microarray is a novel three-dimensional microarray system and can be used to analyze K-ras mutations quickly and accurately. The mutation detection rate was nearly 100% and was similar to that of PCR-SSCP together with sequencing analysis, but the microarray analysis was faster and easier.

Cell Line, Tumor↗
PubMed2004

Outpatient clinic for genetic counseling and gene testing of retinoblastoma.

We report on the genetic counseling and gene testing of patients with retinoblastoma who visited the National Cancer Center Hospital, Tokyo, from April 1997 through September 2003. During this period, 73 probands visited the clinic, and gene testing was performed in 51 individuals. Germline mutations of the RBI gene were detected in 20 individuals (39%); the frequencies were 82% (9/11) in bilateral/familial retinoblastoma, 50% (2/4) in unilateral/familial retinoblastoma, 50% (8/16) in bilateral/nonfamilial retinoblastoma, and 5% (1/20) in unilateral/nonfamilial retinoblastoma. Gene testing is indicated in the medical practice of hereditary retinoblastoma for familial risk assessment, while prior counseling is important for an understanding of the risks and benefits of gene testing. With improvements in patient prognosis, counseling for adult survivors is increasing in importance. Assessment of genetic risk to the offspring and prevention of secondary cancer are the primary issues of concern. Presymptomatic diagnosis of infants is effective for the proper assessment of the genetic risk and for making follow-up schedules for the detection of the tumor at an early stage.

Ambulatory Care Facilities↗
PubMed2004

Association of HNPCC and endometrial cancers.

Hereditary nonpolyposis colorectal cancer (HNPCC) is among the representative familial cancers that are autosomally dominant inherited disorders. Because endometrial cancers develop at high rates in women with HNPCC, it is suggested that some endometrial cancers are familial cancers that are induced by mutations of the DNA mismatch repair (MMR) genes, as in HNPCC. To understand the clinical pathology of familial endometrial cancers that are associated with HNPCC, we surveyed the family histories of 385 patients with endometrial cancer and found that 0.5% of endometrial cancers met the new diagnostic criteria of HNPCC. From molecular and biological analyses, we found microsatellite instability in 30.8% of endometrial cancers and germline mutations of MMR genes in 8.3%. These results suggest a close relationship of MMR gene mutations to the development of endometrial cancers. For a better understanding of the clinical pathology of HNPCC-associated familial endometrial cancers, it is critical for gynecologists to perform a large multicenter study, including detailed family histories.

Chromosomal Instability↗
PubMed2004

Extensive but hemiallelic methylation of the hMLH1 promoter region in early-onset sporadic colon cancers with microsatellite instability.

BACKGROUND AND AIMS: Methylation of the hMLH1 promoter region is frequently observed in microsatellite instability (MSI)-positive sporadic colorectal carcinomas. We studied hMLH1 promoter methylation in peripheral blood lymphocytes of 87 index patients representing 29 cases of hereditary nonpolyposis colorectal cancers (HNPCCs), 28 cases of atypical HNPCCs, and 30 sporadic cases of the development of early-onset colorectal carcinomas or multiple primary cancers. METHODS: Methylation of the hMLH1 promoter region was analyzed by Na-bisulfite polymerase chain reaction/single-strand conformation polymorphism analysis or methylation-specific polymerase chain reaction. MSI, allelic status of the hMLH1 locus, and loss of hMLH1 protein expression were examined in cases for which tumor tissues were available. RESULTS: Extensive methylation of the hMLH1 promoter was detected in peripheral blood lymphocytes of 4 of 30 patients with sporadic early-onset colon cancer, among whom multiple primary cancers (1 colon and 1 endometrial cancer) developed in 2 cases. This methylation was not detected in analyses of HNPCC or atypical HNPCC groups or healthy control subjects. MSI was positive, and extensive methylation was detected in both cancers (colon and endometrial cancer) and normal tissues (colon, gastric mucosa, endometrium, and bone marrow) in all of the examined cases (3 of 3). Analysis of a polymorphic site in the hMLH1 promoter in 2 informative cases showed that methylation was hemiallelic. In 1 case, the unmethylated allele was lost in the colon cancer but not in the metachronous endometrial cancer. CONCLUSIONS: Constitutive, hemiallelic methylation of the hMLH1 promoter region was shown to be associated with carcinogenesis in sporadic, early-onset MSI-positive colon cancers.

Adaptor Proteins, Signal Transducing↗
PubMed2004

The novel germline mutation of the hMLH1 gene in a case of suspected hereditary non-polyposis colorectal cancer (HNPCC) in a patient with no family history of cancer.

Hereditary non-polyposis colorectal cancer (HNPCC) is a very important clinical entity in oncology. In order to identify HNPCC, the international diagnostic criteria, named 'Amsterdam criteria', has been used. In this report, we present a patient with HNPCC who completely lacks a family history of cancer, thus does not meet the revised Amsterdam criteria and was finally confirmed as HNPCC by genetic testing which revealed a novel germline mutation of the hMLH1 gene. The proband was a 52-year-old Japanese female with a diagnosis of advanced ascending colon cancer. She had a past history of Miles' operation for rectal cancer at the age of 40. A subtotal colectomy was performed and the subsequent microsatellite instability (MSI) analysis revealed high MSI in the resected tumor tissue. PCR/direct sequencing analysis of the genomic DNA revealed the base deletion 2006delAAAAG at codon 669 in exon 18 of the hMLH1 gene, which was considered to be a pathogenic mutation. According to the Human Mutation Database and International Collaborative Group on HNPCC (ICG-HNPCC) Database, this is the first report of this type of deletion mutation in the hMLH1 gene.

Adaptor Proteins, Signal Transducing↗
PubMed2004

Establishment of two cell lines from human gastric scirrhous carcinoma that possess the potential to metastasize spontaneously in nude mice.

Few experimental studies have been conducted to clarify the mechanism of development of metastasis in scirrhous carcinoma of the stomach. In the present study, we attempted to establish gastric carcinoma cell lines by incubation of cancer cells collected from the body fluids of patients with gastric cancer. At the same time, xenografting of these cells to nude mice was performed. It was found that, of the gastric carcinoma cell lines thus established, two cell lines, designated as HSC-44PE and HSC-58, formed s.c. tumors with a high infiltrative potential (often invading the lymphatics around the cancer tissue) when implanted. Metastasis to the lymph nodes and lungs was observed in 20-40% of all the animals, indicating that the two cell lines are also capable of metastasizing spontaneously. Through repeated selection, i.e., repeated cycles of removal, culture, and implantation of the HSC cancer cells from metastatic lesions, we obtained 5 subclones of HSC-44PE and HSC-58 (designated as m2509, m2615, m2792, m2917, and m2691), which, when implanted orthotopically, exhibited the following characteristics as compared to the parent cells: (1) a higher percentage take (survival), similar frequency of metastasis, shorter time to metastasis (less than 100 days), and consistent metastasizing potential; (2) a relatively high frequency of metastasis to lymph nodes, including distant metastasis to axillary lymph nodes; (3) the potential to cause occasional bloody ascites; (4) enhanced expression of dysadherin, CD44, and other molecules. This is the first report of cultured scirrhous gastric carcinoma cells showing the potential for spontaneous metastasis.

Adenocarcinoma, Scirrhous↗
PubMed2004

Two Japanese kindreds occurring endometrial cancer meeting new clinical criteria for hereditary non-polyposis colorectal cancer (HNPCC), Amsterdam Criteria II.

Hereditary non-polyposis colorectal cancer (HNPCC), also called Lynch syndrome, is an autosomal dominantly inherited disorder of cancer susceptibility. Patients with HNPCC exhibit an increased risk for HNPCC-associated extracolonic tumors such as cancer of the endometrium. HNPCC is associated with germline mutations in DNA mismatch repair (MMR) genes: hMLH1, hMSH2 and hMSH6. Here, we describe two Japanese kindreds (0.5%) who met the new clinical criteria for HNPCC, Amsterdam criteria II, from among 375 endometrial cancer patients treated at Keio University Hospital from 1990 to 2002. From these results, it was found that female HNPCC patients comprised approximately 0.5% of all endometrial cancer patients. Decreased expression of two MMR gene protein products (hMLH1 and hMSH6) was confirmed immunohistochemically in these two endometrial tumors in HNPCC kindreds. This case report provides important information on Japanese HNPCC patients occurring endometrial cancer.

Adaptor Proteins, Signal Transducing↗
PubMed2003

Unfavorable prognostic factors associated with high frequency of microsatellite instability and comparative genomic hybridization analysis in endometrial cancer.

PURPOSE: Although many articles have been published regarding chromosomal instability (CI) and microsatellite instability (MI) in endometrial adenocarcinoma, the relationship between prognostic factors and the biological mechanisms accounting for genetic instability in these tumors has not yet been precisely defined. To do that, it will be necessary to clarify the molecular mechanisms involved in endometrial carcinogenesis. EXPERIMENTAL DESIGN: Tissue samples from 43 human primary endometrioid endometrial adenocarcinomas (EACs) were analyzed for CI and MI status using comparative genomic hybridization and 11 microsatellite loci, respectively. Methylation status of the promoter of MLH1 was also determined. We analyzed all three of these parameters in relation to each other and to clinicopathological factors. RESULTS: Sixty-five percent of the EACs we examined had detectable CI. Frequent copy number gains were seen at 1q25-41 (23%), 8q11.1-q21.1 (23%), 8q21.3-qter (21%); 28% of these tumors exhibited high-frequency MI (MSI-H); Methylation of the MLH1 promoter was observed in 92% of EACs with MSI-H. Southern blotting showed amplification of MYCN in one tumor, which has been documented for the first time in a primary human EAC. CONCLUSIONS: MSI-H was correlated with histological grade, International Federation of Gynecologists and Obstetricians (FIGO) stage, myometrial invasion, and lymphonode metastasis. Our comparative genomic hybridization results demonstrated that the number of chromosomes involved in genomic alterations in EACs was distinctively fewer than those in other types of tumor. The carcinogenetic process leading to EAC appears to be highly complex; for example, MI and CI may act synergistically, whereas CI and/or MI are likely to be linked with tumor heterogeneity.

Adaptor Proteins, Signal Transducing↗
PubMed2003

Identification of germline MSH2 gene mutations in endometrial cancer not fulfilling the new clinical criteria for hereditary nonpolyposis colorectal cancer.

Endometrial cancer is the second most common malignancy in patients with hereditary nonpolyposis colorectal cancer (HNPCC). This cancer is caused by germline mutations in one of the DNA mismatch repair (MMR) genes. The present study was undertaken to analyze the relation between microsatellite instability (MSI) and germline mutations of MMR genes. We analyzed MSI in 38 cases of endometrial cancer. MSI was present in one or more (out of 5 examined) regions in 11 (29%) cases. Furthermore, alterations in MLH1 and MSH2, two culprit genes representative of HNPCC, were examined in the 11 MSI-positive patients using polymerase chain reaction-single-strand conformation polymorphism and sequencing. Germline mutations, namely, 1) a missense mutation at codon 688 (ATG-->ATA, Met-->Ile) and 2) a missense mutation at codon 390 (CTT-->TTT, Leu-->Phe) of the MSH2 gene, were found in 2 of the 11 patients (18%). Although these two cases do not fulfill the new Amsterdam criteria, they had strong family histories of colorectal and endometrial carcinoma. Our results show that genetic testing is important in cases of endometrial cancer with a history suggestive of HNPCC even if the new Amsterdam criteria are not fulfilled.

Adaptor Proteins, Signal Transducing↗
PubMed2003

Methylation profile of the MLH1 promoter region and their relationship to colorectal carcinogenesis.

Methylation of the MLH1 promoter region has been suggested to be a principal mechanism of gene inactivation in sporadic microsatellite instability (MSI)-positive colorectal carcinoma. Recently, we have shown a novel methylation profile of the MLH1 promoter region (i.e., full, partial, and no methylation), among which full methylation was strongly associated with MSI. In this study, to confirm whether methylation requires the involvement of both alleles, we studied the MLH1 promoter region concerning the methylation profile and allelic loss. Furthermore, we studied correlations of methylation profiles with genetic alternations such as loss of heterozygosity (LOH) of the TP53 locus and KRAS mutation. Eighty-eight tumors were classified as full (n = 14), partial (n = 26), and no methylation (n = 48). Full methylation was observed in 78% (14/18) of high-frequency MSI, in which all CpG sites in the promoter region were methylated. Full methylation differed significantly from partial methylation regarding absence of TP53 LOH (0/12) and KRAS mutation (0/14). In cases with full methylation, we could show biallelic methylation by use of a single-base nucleotide polymorphism in the promoter. However, this did not accompany LOH of the MLH1 locus. In contrast, there were no significant differences in molecular features between partial and no methylation, except for low frequencies of LOH of the MLH1 locus (P = 0.02). In conclusion, biallelic extensive methylation of the MLH1 promoter region plays a significant role in gene inactivation and is independent of KRAS mutation and TP53 LOH.

Adaptor Proteins, Signal Transducing↗
PubMed2003

The novel germline mutation of hMSH2 gene in a case of a hereditary non-polyposis colorectal cancer (HNPCC) patient who meets the revised Amsterdam criteria.

Hereditary non-polyposis colorectal cancer (HNPCC) is a very important clinical entity in oncology. In order to identify HNPCC, the international diagnostic criteria named "Amsterdam criteria" have been used. In this report, we present a case of an HNPCC patient who met the revised Amsterdam criteria after the sequential history taking in which a novel germline mutation of hMSH2 gene was detected by genetic testing. The proband was a 69-year-old Japanese female who was admitted to our hospital with a diagnosis of advanced ascending colon cancer. Microsatellite instability (MSI) analysis revealed high MSI in the resected tumor tissue. PCR/direct sequencing analysis of the genomic DNA revealed the TTG(Leu) to TAG(Stop) nonsense mutation at codon 302 in exon 5 of the hMSH2 gene, which was considered to be a pathogenic mutation. According to the Human Mutation Database and International Collaborative Group on HNPCC (ICG-HNPCC) Database, this type of nonsense mutation is the first report in the hMSH2 gene.

Aged↗
PubMed2003

Hypermethylation of an E-cadherin (CDH1) promoter region in high grade transitional cell carcinoma of the bladder comprising carcinoma in situ.

PURPOSE: We elucidated the role of methylation in the promoter region of the 1 gene in bladder carcinogenesis, particularly in those comprising carcinoma in situ. MATERIALS AND METHODS: A total of 49 cases of transitional cell carcinoma of the bladder obtained from transurethral resection were examined. Methylation status of the 1 promoter region was analyzed by methylation specific polymerase chain reaction from chemically modified DNA after Na-bisulfite treatment. Loss of heterozygosity on 16q was examined by blunt end single strand DNA conformation polymorphism using 4 tetranucleotide repeat microsatellite markers assigned on 16q13 to 22.1. E-cadherin expression was evaluated by immunostaining on formalin fixed, paraffin embedded tissue sections using anti E-cadherin murine monoclonal antibody, HECD1 and standard avidin-biotin immunoperoxidase complex technique. RESULTS: Analysis of the 49 bladder transitional cell carcinoma samples showed 1 promoter methylation in 23 (47%). Methylation of the 1 gene did not correlate with tumor stage (p = 0.2097) but with high grade transitional cell carcinoma (p = 0.0416). 1 promoter methylation was observed at a significantly higher frequency in the carcinoma in situ positive group than in the carcinoma in situ negative group (16 of 18 cases or 89% versus 7 of 31 or 23%, p <0.0001) and it strongly correlated with abnormal E-cadherin expression (p <0.0001). We found 16q loss of heterozygosity in 16 of 47 cases (34%), which correlated with higher histological grade (p = 0.0069) but not with the presence of the carcinoma in situ component (p = 0.1235). CONCLUSIONS: This study showed that 1 gene promoter methylation is strongly associated with bladder transitional cell carcinoma comprising carcinoma in situ.

Alleles↗