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H Ishikura

Publications and source records attributed to H Ishikura.

At least 19 recordsLinked to original sources
PubMed2005

IFN-alpha enhances TNF-alpha-induced apoptosis through down-regulation of c-Myc protein expression in HL-60 cells.

We examined the effect of interferon-alpha (IFN-alpha) in combination with tumor necrosis factor-a (TNF-alpha) on growth, differentiation and apoptosis in HL-60 human myeloid leukemia cells. IFN-alpha inhibited cell growth and induced apoptosis, but not differentiation, in HL-60 cells. IFN-alpha enhanced TNF-alpha-induced apoptosis. We also investigated the expression of c-Myc and Bcl-2 oncoproteins, which are implicated in the survival or death of a cell. The levels of c-Myc protein expression were not changed by IFN-alpha alone at 24hrs of treatment, but were down-regulated at 72 hrs, accompanied by the appearance of apoptotic cells. While, IFN-alpha did not affect the level of Bcl-2 protein expression during this cultivation time. Interestingly, a combination treatment of IFN-alpha with TNF-alpha showed a greater decrease of c-Myc expression than TNF-a alone at 24hrs. Whereas, IFN-alpha did not significantly modulate Bcl-2 expression levels which were down-regulated by TNF-alpha. Therefore, the enhancement of TNF-alpha-induced apoptosis by IFN-a might be closely associated with the greater down-regulation of c-Myc protein, rather than Bcl-2. In contrast, with rapid down-regulation of c-Myc expression caused by TNF-alpha, IFN-alpha down-regulated c-Myc rather late (at 72 hrs), suggesting that both cytokines have a distinct pathway regulating c-Myc protein expression. However, the enhancement of apoptosis in the combination treatment would suggest the presence of a common signaling pathway for induction of apoptosis at down-stream of c-Myc.

Apoptosis↗
PubMed2003

Plasma stromal cell-derived factor-1 during granulocyte colony-stimulating factor-induced peripheral blood stem cell mobilization.

In this report, we examined plasma stromal cell-derived factor-1 levels in normal healthy donors for allogeneic peripheral blood stem cell transplantation (PBSCT) and in patients for autologous PBSCT using an enzyme-linked immunosorbent assay. The average level of plasma stromal cell-derived factor-1 was 2197 pg/ml before granulocyte colony-stimulating factor administration and 1899 pg/ml on day 4, demonstrating a significant decrease in the peripheral blood of healthy donors (P=0.0003). In patients for autologous PBSCT, a significant decrease of plasma stromal cell-derived factor-1 in the peripheral blood was also observed (P=0.0464). However, the physiologic gradient of stromal cell-derived factor-1 between peripheral blood and bone marrow was never inverted in normal healthy donors or in autologous PBSCT patients. Our results suggest that stromal cell-derived factor-1 may not be involved in the granulocyte colony-stimulating factor-induced release of CD34(+) cells to the peripheral blood. Further studies of a possible additive effect of granulocyte colony-stimulating factor and stromal cell-derived factor-1 are warranted.

Adult↗
PubMed2002

Age related expression of Werner's syndrome protein in selected tissues and coexpression of transcription factors.

AIMS: Werner's syndrome (WS) is an uncommon autosomal recessive disease resulting from mutational inactivation of human WRN helicase, Werner's syndrome protein (WRNp). Patients with WS progressively develop a variety of aging characteristics after puberty. The aim of this study was to determine the distribution of WRNp and the expression of the transcription factors regulating WRN gene expression in a variety of human organs in an attempt to understand the WS phenotype. METHODS: Tissue specimens were obtained from 16 controls aged from 27 gestational weeks to 70 years of age and a 56 year old female patient with WS. The distribution of WRNp and the expression of the transcription factors regulating WRN gene expression-SP1, AP2, and retinoblastoma protein (Rb)- were studied in the various human organs by immunohistochemical and immunoblot analyses. RESULTS: In the healthy controls after puberty, high expression of WRNp was detected in seminiferous epithelial cells and Leydig cells in the testis, glandular acini in the pancreas, and the zona fasciculata and zona reticularis in the adrenal cortex. In addition, the SP1 and AP2 transcription factors, which regulate WRNp gene expression, appeared in an age dependent manner in those regions where WRNp was expressed. In controls after puberty, SP1 was expressed in the testis and adrenal gland, whereas AP2 was expressed in the pancreas. CONCLUSIONS: These findings suggest that the age specific onset of WS may be related to age dependent expression of WRNp in specific organs.

Adolescent↗
PubMed2001

Activation of matrix metalloproteinase-2 is correlated with invasiveness in thymic epithelial tumors.

UNLABELLED: BACKGROUND AND OBJECTS: Matrix degradation, which is a critical event in the process of tumor invasion and metastasis, is considered to be caused by the action of proteolytic enzymes. METHODS: We examined the gelatinolytic activity of matrix metalloproteinase (MMP)-9, and the activity of active and inactive forms of MMP-2 in five thymi, five noninvasive thymomas, eight invasive thymomas, and five thymic carcinomas by quantitative gelatinolytic zymography. RESULTS: The gelatinolytic activity of active MMP-2 in five thymi was zero. The mean gelatinolytic activity of active MMP-2 was 0.020 +/- 0.015 in noninvasive thymoma, 0.084 +/- 0.098 in invasive thymoma and 0.246 +/- 0.194 in thymic carcinoma. The gelatinolytic activity of active MMP-2 correlated with the invasiveness of thymic epithelial tumors (Spearman rank correlation: r-value = 0.532). The gelatinolytic activity of active MMP-2 in three thymoma cases with microscopic capsular invasion was the same as that of noninvasive thymoma. When thymoma cases showing microscopic capsular invasion were classified into the "macroscopically noninvasive thymoma" group, the gelatinolytic activity of active MMP-2 correlated with the invasiveness of thymic epithelial tumors (Spearman rank correlation: r-value = 0.621). CONCLUSIONS: The gelatinolytic activity of active MMP-2 significantly correlated with the invasiveness in thymic epithelial tumors. J. Surg. Oncol. 2001;76:169-175.

Enzyme Activation↗
PubMed2001

Clear cell variant of malignant melanoma of the uterine cervix: a case report and review of the literature.

BACKGROUND: A rare variant of malignant melanoma of the uterine cervix mimicking clear cell carcinoma or clear cell sarcoma is described. CASE: A 33-year-old Japanese woman was admitted to the hospital complaining of genital discharge and lower back pain. The stage was FIGO IIB and radical hysterectomy and pelvic lymphadenectomy were done. Pathological examination, immunohistochemical studies of melanin granules, and molecular analysis of the EWS/ATF-1 fusion gene were also done. A diffuse proliferation of amelanotic clear cells was detected in the uterine cervix. Tumor cells were positive for HMB 45, Melan-A (MART-1), and S-100 protein and negative for epithelial markers. The EWS/ATF-1 fusion gene was not detected. CONCLUSION: This is apparently the first report of a case of clear cell melanoma of the uterine cervix. Despite its rarity, this variant of malignant melanoma should be considered when diagnosing clear cell neoplasms of the uterine cervix.

Adenocarcinoma, Clear Cell↗
PubMed2001

Autoimmune neutropenia with cyclic oscillation of neutrophil count after steroid administration.

A 16-year-old female patient was evaluated for pancytopenia. She had a white blood cell count of 1.6 x 10(9)/L with 0.02 neutrophils and a platelet count of 19 x 10(9)/L. In the bone marrow, mature granulocytes were markedly decreased in number, but no atypical cells were present. Antineutrophil antibody was demonstrated by flow cytometry, and the level of platelet-associated immunoglobulin G was increased. A diagnosis of autoimmune neutropenia and thrombocytopenia was made. Interestingly, neutrophil and platelet counts fluctuated cyclically after the initiation of prednisolone therapy. The neutrophil count fluctuated between 0.1 x 10(9)/L and 7 x 10(9)/L, and the platelet count fluctuated between 19 x 10(9)/L and 175 x 10(9)/L, in 4-week cycles. Following splenectomy, neutrophil and platelet counts normalized. We believe the immune mechanism of recurrent neutropenia in this patient differs from that in other patients with cyclic neutropenia reported with stem cell disorders.

Adolescent↗
PubMed2001

Clarification of the active gelatinolytic sites in human ovarian neoplasms using in situ zymography.

Tissues from 26 human ovarian common epithelial tumors were examined to determine where and how gelatinolytic activity was present, in relation to tumor-stromal interaction and histologic types. For this purpose, we used in situ zymography, a newly developed technique using gelatin-coated film. Gelatinolytic activity was evident in ovarian carcinomas and in borderline tumors. Benign tumors had no or only weak activity. Four tissue localization patterns of gelatinolysis were identified: pattern A, tumor cytoplasm; pattern B, tumor-stromal junction; pattern C, stroma; and pattern D, cystic fluid. Mucinous cystadenocarcinomas showed A and/or D patterns. One mucinous and one serous adenocarcinoma and one mucinous borderline tumor had a B pattern. Most serous and all clear cell adenocarcinomas showed strong gelatinolysis of C pattern, especially in the desmoplastic stroma, an area where the tumor cells were dispersed. Immunohistochemically in 12 adenocarcinomas and 3 borderline tumors, the tumor cytoplasm was positive for matrix metalloproteinases (MMP-2) (5 cases), MMP-7 (9 cases), and MMP-9 (6 cases). Stromal components were positive for MMP-2 in 5 cases and for MMP-9 in 3 cases, but they were not positive for MMP-7. MMP antigens were mostly distributed in an almost identical pattern consistent with that seen with in situ zymography. In situ zymography clarified the cellular localization of active gelatinolysis in human ovarian neoplasms, a finding which supports the view that interaction between tumor and stroma is critical for tumor growth. This newly developed method contributes to a better understanding of biologic features of ovarian malignancies.

Adenoma↗
PubMed2001

Anti-Thy-1 monoclonal antibody with specific reactivity with vascular endothelial cells in rat glomeruli.

Inoculation with anti-Thy-1 antibodies (Abs) in rats induces glomerulonephritis resembling human mesangiolytic and/or mesangioproliferative diseases. Some anti-Thy-1 monoclonal Abs (mAbs) react with both mesangial and glomerular endothelial cells, whereas others react solely with mesangial cells in rat kidney. These findings suggest that the rat Thy-1 molecule possesses at least 2 variant forms, including a mesangial and a vascular endothelial isoform. However, anti-Thy-1 mAbs with specific reactivity with glomerular endothelial cells have not been available. We describe here a unique anti-rat Thy-1 mAb, TM78-8. The epitope for TM78-8 is closely related, but not identical, to that for OX-7, a commercially available anti-rat Thy-1 mAb. Immunoblotting, immunohistochemistry and immunoelectron microscopy confirm that TM78-8 reacts exclusively with Thy-1 antigens on the surface of vascular endothelial cells in rat glomeruli. TM78-8 may be a suitable marker for rat glomerular endothelial cells as well as for the vascular endothelial isoform of the rat Thy-1 molecule. Intravenous injection of TM78-8 did not induce glomerulonephritis in rats, whereas OX-7 did, indicating that TM78-8 is not nephritogenic. This finding also corresponds with the current consensus that Thy-1 antigens expressed on mesangial cells play an essential role in the development of Thy-1 nephritis.

Animals↗
PubMed2001

Simultaneous squamous cell carcinomas of the uterine cervix and upper genital tract: loss of heterozygosity analysis demonstrates clonal neoplasms of cervical origin.

Five cases of cervical squamous cell carcinoma with synchronous superficial squamous cell carcinoma in the upper genital tract were genetically analyzed to demonstrate the possibility of a clonal neoplastic process. In these cases, the cervical lesions were squamous cell carcinoma in situ (cases 1, 2, and 3) and invasive squamous cell carcinoma (cases 4 and 5). Loss of heterozygosity (LOH) analyses with a panel of microsatellite markers revealed a monoclonal process in four of the five cases. Homogeneous LOH throughout the microdissected lesions was most frequently detected on 6p and 6q (3 cases), followed by 11p and 11q (2 cases), loci known to be commonly lost in typical cervical squamous cell carcinoma. In two cases, genetic progression in terms of additional LOH was found in the upper genital tract but not in the cervix. Most of these squamous cell carcinomas were monoclonal neoplasms originating from the cervical mucosa with subsequent superficial migration of the tumor clone to the upper genital mucosa, and in some cases, genetic progression.

Aged↗
PubMed2001

Anti-angiogenic treatment for peritoneal dissemination of pancreas adenocarcinoma: a study using TNP-470.

We established peritoneal dissemination-prone subcultures (PCI-43p3) using nude mice by a repetitive in vivo selection of intraperitoneally inoculated PCI-43, a pancreas adenocarcinoma cell line. The subcultures showed upregulated expression of matrix metalloproteinase (MMP)-9, but not MMP-2 in culture supernatants. They also produced increased amounts of vascular endothelial growth factor (VEGF), which was not associated with alterations in isoforms of VEGF mRNA. PCI-43p3 cells attached to cultured mesothelial cell monolayers more readily than did the parent PCI-43 cells. The angiogenesis inhibiting agent, TNP-470, at 30 mg / kg was administered to the model mice, resulting in a prominent suppression of the establishment of peritoneal nodules. The suppression was dependent on the duration of TNP-470 treatment. TNP-470 treatment significantly suppressed proliferation of tumor cells in disseminated nodules, assessed in terms of immunostaining for proliferating cell nuclear antigen (PCNA). TNP-470 did not affect the in vitro attachment between PCI-43p3 and mesothelial cells. The combined data show that anti-angiogenic treatment profoundly suppresses the in vivo process of peritoneal dissemination.

Adenocarcinoma↗
PubMed2001

Vaccination effect of interleukin-6-producing pancreatic cancer cells in nude mice: a model of tumor prevention and treatment in immune-compromised patients.

In an effort to explore properties important in hematogenous metastasis of pancreatic adenocarcinoma, we previously demonstrated that tumor-derived interleukin (IL)-6 is a crucial factor that conveys resistance to liver metastasis. Here we extend the study to examine a possible vaccination effect of tumor-derived IL-6 in T-cell-deficient nude mice, as a model for predicting the effect in immune-compromised patients. We used a pair of IL-6-nonproducing and highly producing pancreatic adenocarcinoma cell lines, PCI-43 and PCI-43h, respectively. The reaction intensity of anti-PCI IgG antibodies in host nude mice was maximal 28 days after inoculation of PCI-43h cells, and remained high thereafter. A fraction of the pancreatic carcinoma cell lines, namely, PCI-6, -10, and -43, expressed surface antigenic determinant(s) reactive with the IgG; but the others, PCI-19, -24, -55, -64, -66, -68, -72, and -79, did not. Inoculation of PCI-43h but not PCI-43 suppressed growth of simultaneously inoculated PCI-43, but not PCI-24 xenografts. In addition, administration of PCI-43h, but not PCI-43 suppressed the growth of PCI-43 that was xenografted 4 weeks later, thus revealing a vaccination effect of IL-6-producing PCI-43h, but not IL-6-nonproducing PCI-43. These data, obtained from T-cell-deficient nude mice, suggest an in vivo role for IL-6 in inducing IgG-mediated, pancreatic carcinoma-specific vaccination against a thymus-independent antigen.

Animals↗
PubMed2001

Suppression of mediastinal metastasis by uracil-tegafur or cis-diamminedichloroplatinum(II) using a lymphogenous metastatic model in a human lung cancer cell line.

PURPOSE AND EXPERIMENTAL DESIGN: The extent of lymphatic metastasis is the most important factor in the prognosis for non-small cell lung cancer (NSCLC). Therefore, suppression of lymphatic metastasis provides an improvement in survival time in lung cancer patients. We established a new patient-like model for lung cancer metastasis by orthotopic implantation in severe combined immunodeficiency (SCID) mice and demonstrated the lymphogenous spread histologically using human NSCLC cell lines. The cardinal features of this model are a simple procedure and a similarity to the metastatic form of human lung cancer. The purpose of this study is to assess the inhibitory action of uracil-tegafur (UFT) and cis-diamminedichloroplatinum(II) (CDDP) on lymphatic metastasis and life span prolongation in our lymphogenous metastatic model system using SCID mice. RESULTS: The inhibition ratios of mediastinal lymph node metastasis were 86.2, 94, and 92.1% for 12 mg/kg body UFT, 17 mg/kg body UFT, and 10 mg/kg body CDDP, respectively. The administration of anticancer drugs prolonged the life span by 4.6 days (17 mg/kg body UFT) and 8 days (10 mg/kg body CDDP) in MST. CONCLUSION: We demonstrated that UFT alone and CDDP alone suppressed mediastinal metastasis and prolonged the life span in our lymphogenous metastatic model. Regardless of the administration route and characteristics of anticancer drugs, cytostatic or cytotoxic, our model is capable of evaluating the inhibitory effect of drugs on lymphatic metastasis. This model should make an important contribution to our understanding of the mechanism and selection of drugs for antilymphatic metastasis in lung cancer.

Animals↗
PubMed2000

Role of c-jun expression increased by heat shock- and ceramide-activated caspase-3 in HL-60 cell apoptosis. Possible involvement of ceramide in heat shock-induced apoptosis.

Ceramide has emerged as a lipid mediator in apoptosis induced by a variety of stresses. As we previously showed that the activation of AP-1, a nuclear transcription factor was indispensable to ceramide-induced apoptosis in human leukemia HL-60 cells (Sawai, H., Okazaki, T., Yamamoto, H., Okano, H., Takeda, Y., Tashima, M., Sawada, H., Okuma, M., Ishikura, H., Umehara, H., and Domae, N. (1995) J. Biol. Chem. 270, 27326-27331), the role and mechanism of heat shock (HS)-increased c-jun expression in apoptosis was here investigated. HS increased morphological changes compatible with apoptosis in human leukemia HL-60 cells, and induced ceramide generation and sphingomyelin hydrolysis with an increase of neutral magnesium-dependent sphingomyelinase activity. When HS failed to induce apoptosis in HS-resistant HL-60 cells, ceramide generation was not detected, suggesting that ceramide was involved in downstream signals required for HS-induced apoptosis. Both HS and N-acetylsphingosine (C(2)-ceramide) increased the expression of c-jun/c-fos mRNAs with the peak 2 h after treatment. When we examined whether the inhibition of c-jun expression by its antisense oligodeoxynucleotides (AS) blocked HS- or C(2)-ceramide-induced apoptosis, AS of c-jun gene inhibited apoptotic morphological changes and DNA fragmentation whereas did not sense oligodeoxynucleotides. Moreover, a synthetic tetrapeptide, acetyl-Asp-Met-Gln-Asp-aldehyde (DMQD-CHO), which inhibited the formation of active form of caspase-3 more efficiently than those of caspase-4, -6, -7, and -8, blocked both caspase-3 like activity, c-jun expression and apoptosis induced by HS or C(2)-ceramide, although DMQD-CHO did not affect HS-induced ceramide generation. These results suggested that the ceramide was generated through sphingomyelin hydrolysis by HS-activated neutral, magnesium-dependent sphingomyelinase and that subsequent c-jun expression through activation of caspase-3 played a role in HS-induced HL-60 cell apoptosis.

Apoptosis↗
PubMed2000

Expression of matrix metalloproteinases and related tissue inhibitors in the cyst fluids of ovarian mucinous neoplasms.

OBJECTIVES AND METHODS: The growth of an ovarian cystic neoplasm often involves its invasion into and destruction of the extracellular matrix. We examined neoplastic cysts of ovarian mucinous tumors for the presence of matrix metalloproteinases (MMPs) and tissue inhibitors of MMPs (TIMPs) using zymography (in situ zymography, gelatin zymography, and casein zymography) and enzyme-linked immunosorbent assay. RESULTS: Matriolytic activity was detected within the cystic contents and cytoplasm of the lining epithelial cells of the cyst by in situ zymography. This intracystic matriolytic activity was thought to originate mainly in the epithelial cells. The activated form of MMP-9 was seen in all carcinoma and borderline fluids and in 7 of 15 adenomas. The concentration of MMP-9 was higher in carcinoma fluids than in borderline and adenoma fluids (P < 0.05). TIMP-1, which specifically binds to MMP-9, was also higher in carcinoma and borderline fluids than in adenoma fluids (P < 0.05). MMP-2 activity was nearly ubiquitously present in all cyst fluids, irrespective of the fluid's histologic category. The amount of MMP-2 was highest in the carcinoma category, although not to a statistically significant degree. TIMP-2, a specific inhibitor for MMP-2, was significantly lower in the borderline category than in the adenoma category. The molar ratios of TIMP-1/MMP-9 (not significant) and TIMP-2/MMP-2 (P < 0.05) were higher in the adenoma category. Expressions of trypsin, MMP-7, and MMP-9 were generally higher in carcinoma and borderline fluids than in adenoma fluids. CONCLUSIONS: These observations indicate the importance of ovarian cystic fluids for analyzing tumor-associated matriolytic activities. The findings suggest that these matriolytic enzymes, together with the presence of their inhibitors, play an important role in the growth of ovarian mucinous tumors.

Adenocarcinoma, Mucinous↗