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Biomedical subjects

S Sagae

Publications and source records attributed to S Sagae.

At least 37 records · Page 2Linked to original sources
PubMed1999

Correlation between expression of the matrix metalloproteinase-1 gene in ovarian cancers and an insertion/deletion polymorphism in its promoter region.

Matrix metalloproteinases (MMPs), a family of closely related enzymes that degrade the extracellular matrix, are likely to be involved in invasion and metastasis of tumor cells. A guanine (G) insertion/deletion polymorphism within the promoter region of MMP-1 influences the transcription of this gene; i.e., the 2G (insertion-type) promoter possesses greater transcriptional activity than the 1G (deletion-type) promoter. To investigate whether this feature contributes to cancer development and/or progression, we genotyped 163 ovarian cancer patients for the polymorphism and then analyzed levels of expression of the MMP-1 gene in their tumors. The proportion of patients who were either heterozygotes or homozygotes for the 2G allele was significantly higher than that observed among 150 individuals without cancer (P = 0.028). Moreover, the levels of MMP-1 expression in cancer tissues among the patients carrying 2G alleles were elevated significantly in comparison with 1G homozygotes (P = 0.0038). By stimulating degradation of extracellular matrix, an excess of MMP-1 production may enhance development and/or rapid progression of ovarian cancers.

Collagenases↗
PubMed1999

Telomerase activity in malignant ovarian tumors with deregulation of cell cycle regulatory proteins.

Using a semiquantitative telomeric repeat amplification protocol assay, telomerase-positive frequencies and enzyme levels were measured. Out of 95% of 49 human ovarian tumors, the highest level of telomerase activity was observed in malignant tumors. Furthermore, by immunohistochemical staining of cell cycle regulatory proteins (pRB, p16, cyclin D1, cyclin E and p53) at the G1 checkpoint, we evaluated the relation between each protein alterations and the levels of telomerase activity. We could not demonstrate a clear relation with each molecule except for cyclin E, but suggesting that aberrant accumulation of these proteins was considered as a reason for telomerase deregulation, which may play an essential role in the pathway of telomerase regulation.

Adult↗
PubMed1999

Genetic analysis of familial and multiple malignancies of endometrial cancer.

The presence of the positive replication errors (RER) phenotype in familial and multiple primary malignancies of endometrial cancer, and its association with a poor prognosis was examined. We analyzed 40 endometrial cancers for RER. Eight endometrial cancers with the RER(+) phenotype at multiple microsatellite loci were detected. The presence of the RER(+) phenotype was higher than in non-familial malignancies. None of the eight cases with the RER(+) phenotype involved multiple primary malignancies; however these patients had shorter survival times. In this study, we suggest that RER examination in endometrial cancer may be useful for establishing a diagnosis of a familial malignancy, and for predicting a poor prognosis.

Endometrial Neoplasms↗
PubMed1999

Mutations of the beta-catenin gene in endometrial carcinomas.

To investigate the contribution of beta-catenin to the development of endometrial carcinoma, we searched for genetic alterations of the beta-catenin gene in primary endometrial carcinomas. Mutational analysis of exon 3 of the beta-catenin gene, encoding the serine/threonine residues for GSK-3 beta phosphorylation, was performed for 35 tumors. Nucleotide sequencing analysis revealed that 5 tumors (5/35, 14%) contained mutations (S33C, S37C, S37F, T41A) that altered potential GSK-3 beta phosphorylation sites. Each of the mutations resulted in the substitution of serine/threonine residues that have been implicated in the down-regulation of beta-catenin through phosphorylation by GSK-3 beta kinase. Furthermore, the incidence of beta-catenin mutations was significantly higher in early-onset (3 of 5) than that in late-onset tumors (2 of 30) (P = 0.014, Fisher's exact test). Replication error (RER)-positive phenotype was not detected in tumors with the beta-catenin gene mutation, although 10 of 35 tumors revealed RER. We performed immunohistochemistry of beta-catenin in 17 cases for which tissue samples were available. We confirmed accumulation of beta-catenin protein in both the nucleus and cytoplasm in 3 tumors, including two in which amino acid alterations had occurred at codon 33 and 37. The other case had no mutation in exon 3. Our results suggested that mutations at serine/threonine residues involved in phosphorylation by GSK-3 beta affected the stability of beta-catenin. Accumulation of mutant beta-catenin could contribute to the development of a subset of endometrial carcinomas, particularly those of the early-onset type.

Amino Acid Substitution↗
PubMed1999

Mutational analysis of beta-catenin gene in Japanese ovarian carcinomas: frequent mutations in endometrioid carcinomas.

To investigate the contribution of the beta-catenin gene to the development of ovarian carcinomas, mutational analysis of exon 3 of the beta-catenin gene was conducted. We analyzed 61 primary ovarian carcinomas, consisting of 49 non-endometrioid-type and 12 endometrioid-type tumors, for genetic alteration of the beta-catenin gene. Five carcinomas showed beta-catenin mutations (S37C, T41I, T41A), including 4 (33%) of 12 endometrioid-type tumors and 1 (14%) of 7 mucinous-type tumors. All of these mutations altered at the serine/threonine residues that are potential sites of GSK3-beta phosphorylation. We detected no carcinomas with interstitial deletion involving exon 3 of beta-catenin. Furthermore, we immunohistochemically studied 27 of the 61 ovarian carcinomas. Both nuclear and cytoplasmic beta-catenin expressions were demonstrated in 4 of the 27 ovarian carcinomas for which tissue samples were available for examination. All 4 cases exhibited mutations in exon 3 of beta-catenin, including a mucinous carcinoma. Our results suggested that beta-catenin gene mutation at potential GSK3-beta phosphorylation sites results in accumulation of beta-catenin protein within the cells and its translocation to nuclei. Accumulated beta-catenin protein may be involved in the development of endometrioid-type ovarian carcinomas, and some mucinous-type ovarian carcinomas.

Adult↗
PubMed1999

Mutational analysis of STK11 gene in ovarian carcinomas.

Recently STK11, the causative gene of Peutz-Jeghers syndrome (PJS) was identified on chromosome 19p13.3. PJS is often accompanied by several malignancies, including breast tumor, adenoma malignum of the uterine cervix, and ovarian tumor. To investigate the involvement of STK11 gene in the development of ovarian carcinomas, we analyzed 30 ovarian carcinomas for loss of heterozygosity (LOH) and STK11 gene mutations. We found one missense mutation (codon 281, Pro to Leu) with heterozygous and somatic status. This mutation occurred at codon 281, which lies within the mutational hot spot (codon 279-281) of STK11 gene previously reported in PJS. We also detected LOH in 2 (11%) of 19 informative ovarian carcinomas. Our results suggest that mutations of the STK11 gene may play a limited role in the development of ovarian carcinomas.

AMP-Activated Protein Kinase Kinases↗
PubMed1999

Interleukin-6 (IL-6) does not change the expression of Bcl-2 protein in the prevention of cisplatin-induced apoptosis in ovarian cancer cell lines.

OBJECTIVE: To study whether interleukin-6 (IL-6) changes the expression of the anti-apoptic Bcl-2 protein in the prevention of cis-diaminedichloroplatinum (II) (CDDP)-induced apoptosis of human ovarian cancer cells. METHODS: Comparative studies were performed on 3 ovarian cancer cell lines after 48 hours of exposure to 0.5-50 ng/ml IL-6, 2 micrograms/ml anti-IL-6 monoclonal antibody (anti-IL-6 mAb), 10 microM CDDP, 10 microM CDDP + 0.5-50 ng/ml IL-6, and 10 microM CDDP + 2 micrograms/ml anti-IL-6 mAb. Apoptosis was measured morphologically and by a DNA fragmentation assay. Bcl-2 protein levels were measured by an ELISA. RESULTS: An increase in apoptosis was observed for each cell line after 48 hours of exposure to 10 microM CDDP. Although high doses of IL-6 decreased the percentage of apoptotic cells, this cytokine did not change the expression of the Bcl-2 protein. CONCLUSION: CDDP-induced apoptosis was negatively controlled by IL-6. However, the anti-apoptic Bcl-2 protein level was not changed by IL-6 in the process of apoptosis in the ovarian cancer cell lines.

Antibodies, Monoclonal↗
PubMed1999

A case of simultaneous presence of primary endometrial carcinoma and metastasis of a breast carcinoma to the ovary after 5 years of tamoxifen therapy.

We report a case of a 43-year-old woman with the simultaneous presence of a primary uterine endometrial cancer and metastasis of breast cancer to the ovary after 5 years of tamoxifen therapy. Tamoxifen therapy lengthens recurrence-free survival of the patient. However, the risk of endometrial cancer and the possibility of recurrence of breast cancer also must be considered.

Adult↗
PubMed1998

Effects of granisetron and its combination with dexamethasone on cisplatin-induced delayed emesis in the ferret.

1. Granisetron and its combination with dexamethasone for the treatment of delayed emesis following cisplatin (CDDP) administration were investigated using ferrets. 2. CDDP-induced emesis was significantly inhibited in both the granisetron group and the combined granisetron and dexamethasone group during the acute and delayed phase in terms of total emesis, latency to first emesis and duration of emesis. 3. Food and water consumption in the combined group of ferrets was significantly increased as compared with the CDDP control group. 4. 5-Hydroxytryptamine (5-HT) level was increased in the ileum and the 5-hydroxyindole acetic acid (5-HIAA) level was increased in the area postrema of ferrets after 3 days of CDDP administration. It is suggested that the antiemetic activity of granisetron and/or dexamethasone is not related to 5-HT levels in delayed emesis. 5. Both granisetron and its combination with dexamethasone are effective in CDDP-induced emesis, but combination treatment is more effective than granisetron alone for the duration of emesis in the delayed phase.

Animals↗
PubMed1998

A case of a malignant mixed tumor in the vagina.

Malignant mixed tumors in the vagina are extremely rare. We experienced a case of a malignant mixed tumor (synovioid variant). Surgical treatment was performed, followed by 3 courses of chemotherapy. Up to the present time, 4 years after the first treatment, no signs of recurrence have been observed.

Biopsy↗
PubMed1998

[Mobilization of peripheral blood stem cells in advanced ovarian cancer].

High-dose chemotherapy with hematopoietic support has been expected to improve the survival of advanced ovarian cancer patients in recent years. An essential component of such treatment has been the ability to collect and reinfuse a large number of peripheral blood stem cells (PBSCs) following high dose therapy. This study was designed to determine which clinical and hematological factors would be better indicators to collect the proper volume of PBSCs. Thirteen patients received a total of 24 courses of induction chemotherapy and 69 of apheresis. We usually mobilized stem cells using CEP chemotherapy (cisplatin 50-70 mg/m2, epirubicin 50 mg/m2 and cyclophosphamide 1.5 g/m2) with G-CSF and CEE regimen (cyclophosphamide 2.0 g/m2, epirubicin 50 mg/m2, and etoposide 50 mg/m2) as a salvage for mobilization. We obtained an average 5 x 10(6)/kg of CD34+ cells for 3 days as one course. The number of CD34+ cells collected significantly depended on the platelets and reticulocytes on the first day of apheresis, but not a nadir of WBCs. It is concluded that apheresis should be started on recovery of WBCs to 5,000-10,000/microliters, of immature granulocytes to > or = 10% and of reticulocytes to > or = 20%. This study confirmed the feasibility of collecting enough PBSCs to use standard chemotherapy of ovarian cancer patients.

Adult↗
PubMed1997

[A randomized cross-over comparative study of granisetron alone and combination of granisetron, methylprednisolone and droperidol as antiemetic prophilaxis in CDDP-based chemotherapy for gynecologic cancer].

A cross-over clinical trial was carried out to compare the efficacy and safety of granisetron alone (40 micrograms/kg) as a "single" group, with that of granisetron, methylprednisolone (250 mg/ body) and droperidol (0.5 ml/body) as a "cocktail" group for control of emesis and vomiting induced by CDDP-based chemotherapy in 68 courses of 34 patients with gynecologic malignancies. At the first course, "single" or "cocktail" drugs were administered at day 1, 2, and 3 of chemotherapy, and at the second course, "cocktail" or "single" drugs in as cross-over fashion. We examined the degree of nausea and frequency of vomiting during the first 7 days of chemotherapy. As for the severity of nausea, the "single" group showed prominent nausea immediately after CDDP and the most severe level at the 3rd or 4th day. The "cocktail" group showed mild symptoms from the next day and it lasted for several days. Vomiting started 12 hours later in the "single" group and the most frequent peak was the 2nd day, whereas the "cocktail" group showed less than one vomiting at the 2nd or 3rd day throughout the treatment. Clinical response (extremely good, good) in the current series of 68 courses of chemotherapy was also evaluated to be 45% and 35% in the "single" group, respectively, against 75% and 20% in the "cocktail" group, respectively. There was no clinical toxicity or side effects in either treatment group. We conclude that the cocktail treatment is very useful for not only acute, but also late emesis in CDDP-based chemotherapy in gynecologic malignancies.

Adolescent↗
PubMed1996

Definition of a commonly deleted region in ovarian cancers to a 300-kb segment of chromosome 6q27.

Allelic deletions of chromosome 6q that occur frequently in ovarian cancers imply the presence of a putative tumor suppressor gene in this chromosomal vicinity. We analyzed DNA from 32 patients with ovarian carcinomas for loss of heterozygosity at loci on the distal portion of chromosome 6q and constructed a detailed deletion map. The map indicated a commonly deleted region between loci D6S149 (defined by CI6-24) and A2, which are estimated to be 300 kb apart on the basis of our cosmid contig map. By means of exon trapping, we found that the human AF-6 gene, which is disrupted in acute myeloid leukemia cells that carry a (6;11)(q27;q23) translocation, is located within the commonly deleted region. Subsequent screening of the AF-6 gene in ovarian carcinomas revealed no mutations. However, our mapping results, which narrowed the region containing the putative tumor suppressor gene to a 300-kb segment of 6q27, will facilitate further efforts to identify a gene associated with ovarian cancer.

Blotting, Southern↗
PubMed1996

Involvement of peptide antigens in the cytotoxicity between 70-kDa heat shock cognate protein-like molecule and CD3+, CD4-, CD8-, TCR-alpha beta- killer T cells.

We previously reported that the 70-kDa heat shock cognate protein-like molecule (hsc70) is expressed on the cell surface along with the neoplastic transformation of rat fibroblast and that this molecule is recognized by CD3+, CD4-, CD8-, NKR-P1-, and TCR-alphabeta- T (DNT) killer cells in an MHC class I-unrestricted fashion. We investigated the mechanism of interaction between hsc70 and DNT cells. H-ras oncogene-transformed rat fibrosarcoma W31 cells expressed hsc70 on the cell surface in almost the same density when the cells were growing in a conventional 5% FCS (5% W31) as when the cell growth was inhibited in the cultivation with 1% FCS (1% W31). However, DNT cells lysed only 5% W31, but not 1% W31. Since these observations suggest that certain peptide Ags of the fast growing W31 cells may play a role in the interaction between hsc70 and DNT cells, we pulsed 1% W31 cells with trifluoroacetic acid (TFA)-extracted fast growing W31 tumor Ags of less than 3000 Da in molecular size. We also pulsed 1% W31 with TFA-extracted Ags from moderate growing W14 tumors and whole fetus tissues. Our data indicated that DNT cells were clearly cytotoxic to 1% W31 pulsed only with TFA-extracted Ags from W31 tumors. Anti-rat hsc70 mAb completely blocked this cytotoxicity. In addition, pronase K treatment of Ags clearly inhibited the cytotoxicity by DNT cells. Taken together, these data suggest that the complex of peptide Ag and hsc70 is involved in the cytotoxic mechanism between hsc70 and DNT cells.

Animals↗
PubMed1996

Mutational analysis of mismatch repair genes, hMLH1 and hMSH2, in sporadic endometrial carcinomas with microsatellite instability.

Microsatellite instability, monitored by replication error (RER), has been observed in both sporadic and hereditary types of endometrial carcinoma. In the hereditary tumors, this instability is considered to be caused by a germline defect in the DNA mismatch-repair system. We previously reported that nearly one-quarter of sporadic endometrial carcinomas examined revealed an RER-positive phenotype at multiple microsatellite loci. To investigate the role of genetic alterations of DNA mismatch-repair genes in sporadic endometrial carcinomas, we screened 18 RER(+) endometrial carcinomas for mutations of hMLH1 and hMSH2. Although we found no germline mutations, we detected two somatic mutations of hMLH1 in a single endometrial cancer; these two mutations had occurred on different alleles, suggesting that two separate mutational events had affected both copies of hMLH1 in this particular tumor. These data implied that mutations of hMLH1 or hMSH2 play limited roles in the development of sporadic endometrial carcinomas, and that the tumors with genetic instability might have alterations of other mismatch-repair genes, such as hPMS1 and hPMS2, or of unknown genes related to the mismatch-repair system.

Adaptor Proteins, Signal Transducing↗
PubMed1996

Interaction between cell-surface-expressed 70-kilodalton heat shock protein-like antigen and CD3(+)4(-)8(-) killer T cells.

The 70-kilodalton heat shock proteins may be expressed on the cell surface by an unknown mechanism and may interact with CD3+4-8- T cell receptor-alpha beta-killer (DNT) cells. In this interaction, certain cellular nascent or mutant peptides may be important (the complexes of 70-kilodalton heat shock protein and cellular peptides directly interact with DNT cells). The results imply that the interaction between 70 kilodalton heat shock proteins and DNT cells may also work in graft rejection. By using antibodies that react with the cell surface-expressed 70-kilodalton heat shock proteins, one may overcome graft rejection.

Animals↗
PubMed1995

Microsatellite instability in endometrial carcinomas: frequent replication errors in tumors of early onset and/or of poorly differentiated type.

Endometrial and ovarian carcinomas are common among women belonging to hereditary nonpolyposis colorectal carcinoma (HNPCC) families; tumors developing in them are characterized by genetic instability due to an inherited dysfunction of the DNA-mismatch-repair system. To clarify the role of similar genetic factors in sporadic forms of gynecological tumors, we examined 77 endometrial and 68 ovarian carcinomas for replication error (RER) at five microsatellite loci. RER-positive phenotypes at two or more microsatellite loci were observed in 18 of the endometrial carcinomas, but in only two of the ovarian carcinomas. Among the patients with endometrial carcinomas, the frequency of RER tended to be higher in those under age 50 than in those over age 60. Furthermore, RER was significantly more frequent in poorly differentiated than in well-differentiated tumors (P = 0.008, Fisher's exact test). These data suggest that genetic factors characterized by RER are likely to play an important role in some endometrial carcinomas, particularly those of early onset and/or of the poorly differentiated type.

Age of Onset↗