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K Yanagihara

Publications and source records attributed to K Yanagihara.

At least 109 records · Page 6Linked to original sources
PubMed1996

Immunohistochemical detection of K-sam protein in stomach cancer.

The K-sam gene, originally isolated as an amplified gene from the stomach cancer cell line KATO-III, is characterized by its preferential amplification in the undifferentiated type (diffuse type) of stomach cancer and encodes one of the receptors for heparin-binding growth factors or fibroblast growth factors. The K-sam gene has been isolated by different methods and has been designated BEK, TK14, and Cek2. The receptor for keratinocyte growth factor was also found to be encoded by the same gene. To examine the expression of the K-sam protein in stomach cancer, polyclonal antibody pK1-2 was raised against the extracellular domain of the gene product. This antibody detected K-sam proteins by Western blot and flow cytometry analyses in stomach cancer cell lines KATO-III and HSC39, in which the K-sam gene is amplified and overexpressed. By immunohistochemical analysis, 20 of 38 cases of the undifferentiated type of advanced stomach cancer were K-sam positive, whereas none of 11 cases of the differentiated or intestinal type revealed K-sam staining. The K-sam product was observed predominantly in diffusely infiltrative lesions. In one autopsy case, the K-sam protein was detected only focally in the primary tumor, whereas markedly increased staining for the K-sam product was detected diffusely in the metastasized tumor in the lymph node and liver. These results suggest that K-sam overexpression is associated with the malignant phenotype of the undifferentiated type of stomach cancer, such as infiltrative growth and metastasis.

Amino Acid Sequence↗
PubMed1995

Retrovirally transmitted gene therapy for gastric carcinoma using herpes simplex virus thymidine kinase gene.

BACKGROUND: Herpes simplex thymidine kinase (HTK) is known to phosphorylate ganciclovir (GCV). Phosphorylated GCV is incorporated into genomic DNA, which leads to inhibition of cell growth and cell death in the replicating cells. Recently, much attention has been drawn to the use of retrovirally mediated gene therapy using HTK as a new therapeutic approach for brain tumors. However, little is known about this phenomenon in gastrointestinal carcinomas. METHODS: The authors transfected the HTK gene packaged in retroviral vector into TMK-1 gastric carcinoma cells (TMK-HTK cells). Sensitivity of TMK-HTK cells to GCV was examined in vitro. Moreover, TMK-HTK cells were transduced into nude mice subcutaneously, and the effects of GCV therapy was examined at the concentration of 20 mg/kg daily for 14 days. RESULTS: TMK-HTK cells were sensitive to GCV at the concentration of 0.1 to 100 micrograms/ml in a dose- and time-dependent manner in vitro. Moreover, 12 of 13 TMK-HTK tumors, which were transduced into nude mice subcutaneously, shrunk from the average diameter of 6.5 mm. CONCLUSION: The results indicate that retrovirally transmitted gene therapy with GCV may provide a new therapeutic approach for treatment of gastric carcinomas.

Animals↗
PubMed1995

Detection of (1-3)-beta-D-glucan in a rat model of aspergillosis.

The G test containing factor G, fractioned from the Limulus lysate, was used to detect (1-3)-beta-D-glucan in a rat model of aspergillosis. Aspergillus fumigatus strain MF-13, 1 x 10(4) conidia, were inoculated transtracheally into rats treated with cortisone acetate (100 mg/kg) and fed a low-protein (8%) diet. Increased serum (1-3)-beta-D-glucan was found on the sixth day after inoculation in concentrations of 370 +/- 178 pg/ml (mean +/- SD) in untreated controls, and 154 +/- 43 pg/ml in rats treated with 0.5 mg/kg of amphotericin B. On day 11 (1-3)-beta-D-glucan concentrations were 2,590 +/- 2,940 pg/ml and 448 +/- 442 pg/ml, respectively. The elevation in levels of (1-3)-beta-D-glucan increased in correlation with the elevation of galactomannan antigen titers; (1-3)-beta-D-glucan is thus measurable during experimental aspergillosis in rats.

Amphotericin B↗
PubMed1995

Radiation-induced apoptotic cell death in human gastric epithelial tumour cells; correlation between mitotic death and apoptosis.

The mode of cell death in cells undergoing mitotic death after gamma-irradiation was studied in seven human gastric epithelial tumour cell lines and two strains of normal gastric fibroblasts. Apoptotic cells were frequently observed in all tumour lines after irradiation, whereas the two fibroblast strains were quite low in apoptosis frequency. The advent of apoptosis depended on the radiation doses and incubation time. Detailed analysis of one of the carcinoma lines, SH101-P4, revealed that G2-phase arrest was maximum at 12 h postirradiation. The cells began to escape G2 arrest by 24 h. Apoptotic cells began to increase at 12 h postirradiation and became maximal from 72 to 96 h. Apoptosis developed in the G1 phase of the cell cycle subsequent to the irradiation. These results suggest that apoptosis is one of the modes of mitotic death after irradiation.

Adenocarcinoma↗
PubMed1995

Over-expressed ZF5 gene product, a c-myc-binding protein related to GL1-Kruppel protein, has a growth-suppressive activity in mouse cell lines.

ZF5 encodes a zinc finger protein, which contains five C2H2-type zinc fingers showing homology with the zinc finger of the Kruppel family, and binds to two sites in the mouse c-myc promoter. We report the effect of over-expression of ZF5 on cell growth. ZnCl2 treatment suppressed the growth of a mouse fibroblast cell line (L cells) transfected with the wild-type ZF5 gene driven by the metallothionein promoter. Cells transfected with the wild-type ZF5 gene formed colonies two- to fivefold less efficiently than those transfected with the mutant ZF5 gene in P19, NIH3T3, 3T3-L1 and L cells. Over-expression of ZF5 did not cause c-myc down-regulation or arrest of the cell cycle, but increased the DNA content.

3T3 Cells↗
PubMed1995

A radiation-induced murine ovarian granulosa cell tumor line: introduction of v-ras gene potentiates a high metastatic ability.

A non-metastatic epithelial tumor cell line, OV3121, was established from ovarian granulosa cell tumor in B6C3F1 mouse irradiated with 60Co-gamma rays. OV3121 cells showed an epithelial morphology and grew in monolayer with a population doubling time of 28-30 h. The production of estradiol and the expression of cytokeratin confirmed the epithelial origin of the line. No pulmonary metastasis was observed from solid tumors after subcutaneous (s.c.) injection or after intravenous (i.v.) injection of a clonal subline, OV3121-1 cells. We examined the experimental metastasis of individual clones of OV3121-1 cells, containing various introduced viral oncogenes: v-Ha-ras, v-Ki-ras, v-fms, v-mos, v-raf, v-src, v-sis, v-fos and v-myc. Among them, only OV3121-1 cells with v-Ha-MuSV or v-Ki-MuSV produced lung colonies at high frequencies. In a more detailed analysis, the v-Ha-ras transfectants OV-ras4 and OV-ras7 were found to form colonies in various organs by metastasis from tumors after s.c. injection, as well as lung colonies after i.v. injection. Moderately metastatic OV-ras7 cells showed high gelatinolytic activity at 72 kDa (MMP-2) and 92 kDa (MMP-9) as compared with the parental OV3121-1 and OV-Neo control cells by zymographic analysis. However, more metastatic OV-ras4 cells produced progressively weaker bands of 72 kDa gelatinolytic activity. No gross alterations in the expression of MMP-1, MMP-3, TIMP-1 and TIMP-2 transcripts were detected in these cell lines. These results suggest that this ovarian granulosa cell tumor line may provide a useful system for understanding the mechanisms by which oncogenes influence the occurrence of metastasis.

3T3 Cells↗
PubMed1995

Bilateral painful epileptic seizures of the hands.

Secondary sensory seizures (SSS) are very rare epileptic seizures. A 14-year-old male patient with habitual painful seizures of the backs of both hands since the age of four is reported. The painful seizures were rarely followed by impairment of consciousness. Ictal EEG showed 4 to 6Hz rhythmic waves over the right anterior and mid-temporal area following complaints of pain. The absence of tumorous lesions on brain CT or MRI, childhood onset and the absence of combined seizures were characteristic features of this case compared with other patients reported to have SSS.

Brain↗
PubMed1995

[Basic and clinical evaluation of lysis centrifugation in candidemia].

Basic and clinical evaluation of lysis centrifugation using Isolator 10 was performed and compared with culture bottle methods. Blood, which was inoculated with C. albicans, C. tropicalis or C. parapsilosis, was cultured using lysis centrifugation or culture bottle method. The culture duration of C. albicans and C. parapsilosis by lysis centrifugation was shorter than that by the culture bottle (BHI release). C. albicans, C. parapsilosis and C. tropicalis became culture-positive within 1 or 2 days after culture by lysis centrifugation. C. albicans and C. parapsilosis became positive 4 days and C. tropicalis 6-8 days after culture by the culture bottle (BHI super). Clinical evaluation of both blood culture method as performed from April 1990 to March 1994. Sixty samples (4.4%) were positive out of 1370 samples. Twenty eight samples (7.2%) were positive out of 389 samples, which were examined by both methods. Twenty two samples were positive by both methods and the rest of the 6 samples was positive only by Lysis centrifugation.

Blood↗
PubMed1995

[Isolation of Cryptococcus neoformans from environments (pigeon excreta) in Nagasaki].

Cryptococcosis is one of the serious deep-seated mycoses in immunocompromised patients, especially those with AIDS. Cryptococcus neoformans ordinarily lives in natural environments such as soil and reproduces in pigeon excreta. It spreads in the air and infects human by inhalation. We isolated C. neoformans from pigeon excreta in hospitals, private houses, parks in Nagasaki from October to December in 1994. C. neoformans was isolated from 4 of 8 samples (50%) of pigeon excreta and the isolation rate increased to 80% (4/5) if they were weathered excreta. Two patients with pulmonary cryptococcosis occurred in the last two years in the area where C. neoformans was isolated during that period. Epidemiological studies of clinical isolates and environmental isolates are important to determine its origin of infection and the route of transmission.

Animals↗
PubMed1995

[Anterior nerve roots enhancement on MRI in a case of Guillain-Barré syndrome].

A 4-year-old girl with Guillain-Barré syndrome (GBS) showed the abnormal enhancement on MRI in the anterior nerve roots corresponding to the region of her muscle weakness on the 26th day of illness. The enhancement on MRI almost disappeared on the 89th day of illness, when her symptoms had more improved. We think that enhanced spinal MRI is useful to reveal the involved nerve roots and the degree of the illness in GBS.

Child, Preschool↗
PubMed1994

A truncated beta-catenin disrupts the interaction between E-cadherin and alpha-catenin: a cause of loss of intercellular adhesiveness in human cancer cell lines.

Cadherin cell adhesion molecules play an essential role in creating tight intercellular association and are considered to work as an invasion suppressor system of cancer cells. They form a molecular complex with catenins, a group of cytoplasmic proteins including alpha- and beta-catenins. While alpha-catenin has been demonstrated to be crucial for cadherin function, the role of beta-catenin is not yet fully understood. In this study, we analyzed the cadherin-catenin system in two human cell lines, HSC-39 and its putative subline HSC-40A, derived from a signet ring cell carcinoma of stomach. These cells grow as loose aggregates or single cells, suggesting that their cadherin system is not functional. In these cell lines, an identical 321-base pair in-frame mRNA deletion of beta-catenin was identified; this led to a 107-amino-acid deletion in the NH2-terminal region of the protein. Southern blot analysis disclosed a homozygous deletion in part of the beta-catenin gene. On the other hand, these cells expressed E-cadherin, alpha-catenin, and plakoglobin of normal size. Immunoprecipitation analyses showed that E-cadherin was coprecipitated with the mutated beta-catenin but not with alpha-catenin, and antibodies against beta-catenin did not copurify alpha-catenin. However, the recombinant fusion protein containing wild-type beta-catenin precipitated alpha-catenin from these cells. These results suggest that the dysfunction of E-cadherin in these cell lines is due primarily to its failure to interact with alpha-catenin, and that this defect results from the mutation in beta-catenin. Thus, it is most likely that the association between E-cadherin and alpha-catenin is mediated by beta-catenin, and that this process is blocked by NH2-terminal deletion in beta-catenin. These findings indicate that genetic abnormality of beta-catenin is one of the mechanisms responsible for loosening of cell-cell contact, and may be involved in enhancement of tumor invasion in human cancers.

Animals↗
PubMed1994

[Evaluation for rapid detection of rifampicin-resistant mycobacterium tuberculosis by polymerase chain reaction-single strand conformation polymorphism].

We evaluated usefulness of the rapid diagnostic method for detection of rifampicin (RFP)-resistant Mycobacterium tuberculosis, which was based on polymerase chain reaction. The MICs of RFP were measured for 38 clinical isolates of Mycobacterium tuberculosis which were suspected to be RFP-resistant organisms, and 12 strains were found to be resistant to RFP. The PCR primers used were the same as those reported by Telenti et al, which were targeting the RNA polymerase beta subunit gene (rpoB). We confirmed that this gene was possessed by all the strains tested. Eight strains out of the 12 strains with RFP-resistant phenotype were demonstrated to have a point mutation or some alterationin the rpoB gene on the basis of PCR-single strand conformation polymorphism (SSCP). Thus, the sensitivity of our method was calculated as 67%. In addition, we could not detect any alterations in the rpoB gene by all RFP-susceptible strains. These results indicated that rapid detection of the RFP-resistant Mycobacterium tuberculosis was possible directly from clinical specimens by using PCR-SSCP technique.

Base Sequence↗
PubMed1994

[A resected case of sporadic myxoma of the right ventricle: the diagnosis was supported with DNA flow cytometry].

We report a rare case of a 16-year-old male who had myxoma originating from septal band of the right ventricle. His ECG anomaly was found incidentally upon a physical examination. Subsequently, echocardiography and angiocardiography demonstrated a tumor occupying the right ventricular outflow tract and protruding into the main pulmonary artery in systolic phase. He was operated upon using extracorporeal circulation. By right ventriculotomy the tumor was resected together with septal tissue 5 mm around the stalk, which branched into the myocardium. The defect was closed using mattress sutures with Dacron felt strips. We also analyzed the DNA content of the tumor. The DNA flow cytometry yielded a single cell population with diploid DNA content. This result showed that the tumor is sporadic form of cardiac myxoma. His postoperative course was uneventful. Thirty months after the surgery, patient has no sign of recurrence. The DNA flow cytometry is helpful for detecting clinical behavior of the cardiac myxoma, because microscopic examination can not readily distinguish sporadic myxoma from so-called complex myxoma.

Adolescent↗
PubMed1993

Antiproliferative effects of isoflavones on human cancer cell lines established from the gastrointestinal tract.

Seven isoflavones, biochanin A, daidzein, genistein, genistin, prunectin, puerarin, and pseudobaptigenin were tested for cytostatic and cytotoxic effects on 10 newly established cancer cell lines of the human gastrointestinal origin. Proliferation of HSC-41E6, HSC-45M2, and SH101-P4 stomach cancer cell lines was strongly inhibited by biochanin A and genistein, whereas other stomach, esophageal, and colon cancer lines were moderately suppressed by both compounds. Biochanin A and genistein were cytostatic at low concentrations (< 20 micrograms/ml for biochanin A, < 10 micrograms/ml for genistein) and were cytotoxic at higher concentrations (> 40 micrograms/ml for biochanin A, > 20 micrograms/ml for genistein). DNA fragmentation was observed at cytotoxic doses of both compounds, indicating the apoptotic mode of cell death by the compounds. Chromatin condensation and nuclear fragmentation of each cell line were also observed. The advent of apoptosis was dose dependent for both isoflavones. Biochanin A suppressed tumor growth of HSC-45M2 and HSC-41E6 lines in athymic nude mice. Our results suggest that two of isoflavone derivatives, biochanin A and genistein, inhibit the cell growth of stomach cancer cell lines in vitro through activation of a signal transduction pathway for apoptosis. Moreover, in vivo experiments demonstrate that biochanin A can be used as an anticancer agent.

Animals↗
PubMed1993

Transcriptional repressor ZF5 identifies a new conserved domain in zinc finger proteins.

We have cloned a cDNA encoding a new murine C2H2 zinc finger protein, ZF5. The 51.3 kD protein contains five GL1-Kruppel type zinc fingers at the C-terminus. At its N-terminus, ZF5 has a 41 amino acid region which was found to be homologous to the N-termini of several other zinc finger proteins. This region defines a new motif within zinc finger proteins which we have named the Zinc finger N-terminal (ZiN) domain. ZF5 binds to two sites in the c-myc promoter and to the -50 bp site of the herpes simplex thymidine kinase promoter. ZF5 is a transcriptional repressor and its repression domain is located N-terminal to the zinc finger domains. A single 4 kb ZF5 mRNA is expressed widely.

Amino Acid Sequence↗