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Akiko Horiuchi

Publications and source records attributed to Akiko Horiuchi.

At least 19 recordsLinked to original sources
PubMed2007

Hedgehog signal pathway is activated in ovarian carcinomas, correlating with cell proliferation: it's inhibition leads to growth suppression and apoptosis.

The hedgehog (Hh) signal pathway has recently been shown to be activated in human malignancies. However, little is known about its role in the development or patient prognosis of epithelial ovarian carcinoma. In the present study, we examined in vivo and in vitro the expression and functional role of Hh signal molecules in epithelial ovarian tumors and normal ovarian surface epithelial (OSE) cells. The expression of Shh, Dhh, Ptch, Smo and Gli1 proteins was not observed in normal OSE, but was increased stepwise in benign, borderline and malignant neoplasms. In addition, immunoreactivity for Shh, Dhh, Ptch, Smo and Gli1 was highly correlated with cell proliferation assessed by Ki-67. Blocking the Hh signal using either the Hh pathway inhibitor cyclopamine or Gli1 siRNA led to remarkably decreased cell proliferation in ovarian carcinoma cells. Treatment with cyclopamine induced not only G, arrest but also apoptosis along with the downregulation of cyclin A and cyclin D1, and the upregulation of p21 and p27. Among the Hh signal molecules, Dhh expression was correlated with poor prognosis of ovarian carcinoma patients. These findings suggest that the Hh signal pathway plays an important role in ovarian tumorigenesis as well as in the activation of cell proliferation in ovarian carcinomas. Thus, the Hh signal pathway is a possible molecular target of new treatment strategies for ovarian carcinoma.

Apoptosis↗
PubMed2006

Expression of semaphorins, vascular endothelial growth factor, and their common receptor neuropilins and alleic loss of semaphorin locus in epithelial ovarian neoplasms: increased ratio of vascular endothelial growth factor to semaphorin is a poor prognostic factor in ovarian carcinomas.

Semaphorins (SEMAs) compete with vascular endothelial growth factor (VEGF) for receptor neuropilin 1 (NP1) and 2 (NP2) and suppress angiogenesis. To clarify the involvement of SEMA and VEGF in the development and progression of ovarian carcinoma, we analyzed the immunohistochemical expression of SEMA, VEGF, NP1, and NP2 in 105 epithelial ovarian tumors. In addition, loss of heterozygosity at SEMA gene loci was examined. Strong expression of SEMA was found in 48% of benign, 33% of borderline tumors, and 13% of carcinomas (P < .05). Positivity for SEMA was significantly decreased in stage IV carcinomas and the expression of SEMA was significantly lower in peritoneal metastases than in primary lesions. Expression of SEMA showed a weak inverse correlation with microvessel density, but the correlation was not statistically significant. Loss of heterozygosity at SEMA3B or SEMA3F was demonstrated in none of the benign tumors, 8% of borderline tumors, and 29% of carcinomas. Expression of NP1 and NP2 was significantly higher in carcinomas than in benign tumors (P < .0001 and .0002, respectively). Patients with ovarian carcinoma with a high VEGF/SEMA ratio showed poorer survival than those with a low VEGF/SEMA ratio (P = .005). Decreased expression of SEMA and increased expression of NP1 and NP2 are characteristics of ovarian carcinomas, and loss of SEMA expression may play an important role in ovarian carcinoma progression. A high VEGF/SEMA ratio has adverse prognostic significance in patients with ovarian carcinoma.

Female↗
PubMed2006

Nuclear expression of S100A4 is associated with aggressive behavior of epithelial ovarian carcinoma: an important autocrine/paracrine factor in tumor progression.

Although S100A4 expression has reportedly been associated with metastasis of various malignancies, little is known about its biological significance in ovarian carcinomas. In this study, we investigated expression and secretion of S100A4 and its extracellular function in ovarian carcinoma cells. We first used immunohistochemistry to examine the expression and localization of S100A4 in 113 epithelial ovarian neoplasms (24 benign, 20 borderline, and 69 malignant tumors) and analyzed its prognostic significance in patients with ovarian carcinoma. Then we investigated the expression, subcellular localization, and secretion of S100A4 in four ovarian carcinoma cell lines. Finally, we examined the effect of S100A4 treatment on the cell proliferation and invasiveness of ovarian carcinoma cells, along with activation of small GTPase, RhoA. Both cytoplasmic and nuclear expressions of S100A4 were significantly stronger in carcinomas than those in benign and borderline tumors. Ovarian carcinoma patients with strong nuclear S100A4 expression showed a significantly shorter survival than those without (P = 0.0045). This was not the case for cytoplasmic S100A4 expression. Ovarian carcinoma cell lines were shown to express S100A4, and secrete S100A4 into the culture media. Treatment with recombinant S100A4 resulted in the upregulation of S100A4 expression, translocation of S100A4 into the nucleus, and enhancement of invasiveness, which was associated with the upregulation of small GTPase, RhoA. These findings suggest that the nuclear expression of S100A4 is involved in the aggressive behavior of ovarian carcinoma and S100A4 is an autocrine/paracrine factor that plays an important role in the aggressiveness of ovarian carcinoma cells.

Active Transport, Cell Nucleus↗
PubMed2006

Peroxisome proliferator-activated receptor gamma ligands stimulate myeloid differentiation and lipogenensis in human leukemia NB4 cells.

Peroxisome proliferator-activated receptor gamma (PPARgamma) plays a central role in adipocyte and macrophage differentiation. Pioglitazone (Actos, AD4833), an antidiabetic drug, and 15-deoxy-Delta(12,14)-prostaglandin J2 (PGJ2) have recently been identified as synthetic and natural ligands for PPARgamma, respectively. In this study, we examined the effects of PPARgamma ligands on differentiation and lipogenesis in promyelocytic leukemia NB4 cells, in which PPARgamma protein was expressed and ligand-stimulated PPARgamma-specific transcription of adipocyte fatty-acid binding protein was confirmed. Treatment with PPARgamma ligand (AD4833 or PGJ2) alone markedly suppressed proliferation but did not induce differentiation. The combined treatment of the cells with PPARgamma ligand and all-trans retinoic acid (ATRA) synergistically induced myelocytic differentiation, as determined by nitroblue tetrazolium reducing ability and cell morphology. During these processes of differentiation, we observed marked accumulation of lipid droplets in the cytoplasm. The cellular triacylglycerol levels increased 2.7-fold after treatment with the inducers. Simultaneously, BODIPY-fatty acid was incorporated into the cytosol and concentrated in lipid droplets. The biosynthesis of triacylglycerol-containing BODIPY-fatty acids was increased twofold in differentiated cells. These findings clearly demonstrate that treatment with PPARgamma ligands not only induced differentiation but also stimulated lipogenesis in NB4 cells, indicating a close association between differentiation and lipogenesis in PPARgamma-stimulated human myeloid cells.

Adipocytes↗
PubMed2005

Intratumoral heterogeneous expression of p53 correlates with p53 mutation, Ki-67, and cyclin A expression in endometrioid-type endometrial adenocarcinomas.

To further elucidate the significance of p53 mutation in endometrial carcinoma, we investigated it in endometrioid-type endometrial carcinomas showing intratumoral heterogeneous p53 expression. In addition, we also examined the correlation of p53 mutation and cyclin A expression, because we previously reported a topological correlation between the expression of p53 and cyclin A. The p53 mutation in exons 5-8 in 54 cases of endometrial carcinoma showing immunohistochemical expression of p53 was examined using microdissected tissue DNAs. Of the 54 p53-positive endometrial carcinomas, 23 (43%) had p53 mutation with a tendency in histologically higher grade tumors. Ten of the 54 showed a heterogeneous p53 expression, and in 9 of the 10 cases, p53 mutation was present only in p53-positive sites, which were often found in histologically less differentiated areas with elevated Ki-67 in the same tumor. Cyclin A expression was topologically observed in p53-positive areas; however, it was noted in both tumors with (12/23, 52%) and without (18/31, 58%) p53 mutation. These results suggest that p53 mutation is a late event and plays an important role in the acquisition of malignant potentials in endometrioid-type endometrial adenocarcinomas. Unexpectedly, accumulation of the p53 protein itself may be important in cyclin A overexpression.

Adult↗
PubMed2005

The effect of free and polyethylene glycol-liposome-entrapped albendazole on larval mobility and number in Toxocara canis infected mice.

As part of our exploratory drug research on the larva migrans that causes roundworm in dogs and cats, this study was carried out to clarify the effect of free and liposome-entrapped (LE) albendazole in Toxocara canis infected mice. In infected mice, evaluation of mobility and number of larva were examined in detail in the brain, skeletal muscle and liver. Larva mobility was evaluated by using the relative mobility (RM) value. Albendazole was LE as one of the drug delivery systems (DDSs). Polyethylene glycol (PEG) was added to the liposome in order to avoid evoking a response by the reticuloendothelial system (RES). By using the albendazole PEG-LE delivery system, it was possible to target the larvae in the mouse brain and liver resulting in a decrease in the number of larvae. In the skeletal muscle of the infected mice, the intraperitoneal dosages of PEG-LE albendazole did not cause a complete decrease in the number of larvae, even though free albendazole did cause the number to decrease. Therefore, it is necessary to take into consideration the migrating stage of the larvae before the initiation of any drug administration.

Albendazole↗
PubMed2005

Toxocara canis: search for a potential drug amongst beta-carboline alkaloids--in vitro and mouse studies.

The goal of this study was to search for new treatments for Toxocara canis using both in vitro and in vivo experiments. We specifically looked for a treatment for T. canis larva migrans, and examined beta-carboline alkaloids (17 compounds) with various structural modifications, both in in vitro and in vivo experiments. In the in vitro experiments, screening for nematocidal activity on the T. canis second stage larvae, cytotoxic activity, and immune activity in the host were undertaken. Compound 17 was selected, as it exhibited nematocidal activity for T. canis larvae and did not have any cytotoxic or immunosuppressive activity in the host. The effectiveness of compound 17 was then examined using T. canis larvae infected mice in in vivo experiments. To evaluate the anthelmintic effect, the relative mobility value for the larvae was examined in addition to the number of larvae in the brain, skeletal muscle, and liver. Compound 17 was also examined in both free and liposome-entrapped (LE) forms. Polyethylene glycol (PEG)-LE compound 17 showed an anthelmintic effect in which the number of larvae in the brain was decreased compared free albendazole. PEG-LE compound 17 also effectively suppressed the mobility of the larva in brain and skeletal muscle. The experimental procedure employed assisted in the discovery of this potential candidate and is a promising approach for finding alternative therapeutic regimens for T. canis larva migrans.

Alkaloids↗
PubMed2004

Expression of BRCA1 protein in benign, borderline, and malignant epithelial ovarian neoplasms and its relationship to methylation and allelic loss of the BRCA1 gene.

BRCA1 is a putative tumour suppressor gene responsible for a hereditary ovarian cancer syndrome. To clarify the possible involvement of BRCA1 in the development of sporadic ovarian neoplasms, this study analysed the immunohistochemical expression of BRCA1 protein in normal ovarian surface epithelium and 119 epithelial ovarian tumours (19 benign, 24 borderline, and 76 malignant tumours). Loss of heterozygosity (LOH) of BRCA1 was examined using three microsatellite markers to analyse the relationship between BRCA1 expression and alterations of the BRCA1 gene. Methylation of the BRCA1 promoter was also analysed by methylation-specific PCR. In ovarian carcinomas showing heterogeneous expression of BRCA1 protein in the same tumour, LOH and methylation status were analysed using microdissection techniques. Finally, the relationship of BRCA1 expression or its genetic alteration to clinicopathological parameters and patient survival was analysed. Ovarian surface epithelial cells expressed BRCA1 protein. Decreased expression of BRCA1 was found in 16% of benign tumours, 38% of borderline tumours, and 72% of carcinomas. LOH of BRCA1 was demonstrated in no benign tumours, 15% of borderline tumours, and 66% of carcinomas. Methylation of BRCA1 was not detected in benign or borderline tumours, but was present in 31% of carcinomas. Reduced expression of BRCA1 correlated with the presence of gene methylation. The frequency of BRCA1 methylation and LOH was higher in serous carcinomas than in other types. In one of the three serous carcinomas that showed heterogeneous expression of BRCA1, BRCA1-positive borderline-like tumour cells were LOH-positive and methylation-negative, whereas adjacent BRCA1-negative carcinoma cells were LOH-positive and methylation-positive. The prognosis of carcinoma patients did not correlate with BRCA1 expression or genetic status. These findings suggest that reduced expression of BRCA1 protein along with genetic and epigenetic changes of the BRCA1 gene play an important role in the development of sporadic ovarian carcinomas, particularly those of serous histology.

Adult↗
PubMed2004

Expression of the mitogen-inducible gene-2 (mig-2) is elevated in human uterine leiomyomas but not in leiomyosarcomas.

To investigate the role of a recently cloned cell proliferation-related gene, mig-2 (mitogen-inducible gene-2), in the growth of uterine leiomyomas, this gene's expression at mRNA and protein levels was examined in normal myometrium, leiomyomas, and leiomyosarcomas of the uterus. Northern blotting, Western blotting, and immunohistochemical staining demonstrated that mig-2 expression was increased in leiomyomas compared with normal myometrium, especially during the secretory phase of the menstrual cycle. In contrast, the mig-2 expression was greatly decreased in leiomyosarcomas. Direct sequencing of the whole coding region of mig-2 cDNA and Southern blotting revealed that mig-2 alterations, such as mutations, rearrangement, and amplification, were not present in either leiomyomas or leiomyosarcomas. These findings suggest that mig-2 expression is transcriptionally elevated in leiomyomas and could be involved in its hormone-mediated growth of leiomyomas of the uterus.

Basic Helix-Loop-Helix Proteins↗
PubMed2004

Elevated expression of E-cadherin and alpha-, beta-, and gamma-catenins in metastatic lesions compared with primary epithelial ovarian carcinomas.

E-cadherin and catenins play key roles in cell adhesion and motility. Little is known about the changes in expression of these molecules in the progression of ovarian carcinomas. In the present study, the immunohistochemical expression of E-cadherin and alpha-, beta-, and gamma-catenins was examined in 77 cases of ovarian carcinoma. In addition, the expression of these molecules was evaluated in 26 matched pairs of primary and metastatic lesions of advanced ovarian carcinomas. Of the 77 primary lesions, positive staining for E-cadherin and alpha-, beta-, and gamma-catenin was observed in 75 (97%), 63 (82%), 71 (92%) and 57 (74%) cases, respectively. Positivity for E-cadherin and alpha-, beta-, and gamma-catenin was significantly decreased in stage III and IV tumors compared with stage I and II tumors, suggesting that expression of the cadherin-catenin complex is reduced with the advancing stages of a tumor. Interestingly, expression of E-cadherin and alpha-, beta-, and gamma-catenin in the lesions of peritoneal dissemination was significantly increased compared with the primary lesions. These findings suggest that expression of the cadherin-catenin complex changes markedly and that reexpression may occur during the peritoneal dissemination of ovarian carcinoma cells.

Adenocarcinoma↗
PubMed2004

Ovarian non-small cell neuroendocrine carcinoma with paraneoplastic parathyroid hormone-related hypercalcemia.

Ovarian tumors associated with hypercalcemia due to ectopic secretion of parathyroid hormone (PTH) are extremely rare. A 33-year-old woman presented with a pelvic mass and profound hypercalcemia accompanied by an elevated serum level of PTH. Laparotomy demonstrated a left ovarian tumor that on histological examination was a neuroendocrine carcinoma of non-small cell type admixed with a component of endometrioid adenocarcinoma. After left salpingo-oophorectomy, the serum calcium and PTH levels normalized. The cells of the neuroendocrine carcinoma were positive for neuron-specific enolase, synaptophysin, chromogranin A, and PTH. Hypercalcemia and elevated serum PTH levels recurred during tumor relapse, and the patient died of disease 6 months postoperatively. This is the eleventh case of neuroendocrine carcinoma of non-small cell type associated with surface epithelial neoplasm of the ovary, and the first such tumor to be associated with hypercalcemia.

Calcium↗
PubMed2003

Electrochemotherapy for digital chondrosarcoma.

Electrochemotherapy (ECT) delivers nonpermeable anticancer drugs to cell interiors by temporally increasing the permeability of the cytoplasmic membrane under locally applied pulsating electrical stimuli. This treatment results in consistent and enhanced pharmacological effects of drugs on the targeted tissue. ECT has been used for surface skin cancer but never for musculoskeletal tumors. This report describes a clinical trial of ECT for digital chondrosarcoma. A 74-year-old woman with a digital chondrosarcoma was administered electric stimulation with two surface electrodes 10 min after intratumoral multiple injection of bleomycin sulfate and 15 s after intraarterial perfusion of bleomycin sulfate. Biopsy performed after ECT showed 90% tumor necrosis. Marginal resection of the tumor was followed by autologous bone grafting to fill the bone defect. Although the follow-up period was short (3 years), the patient remained disease-free after ECT and was satisfied that amputation of the affected finger could be avoided. This preliminary result suggests that ECT is a viable modality for limb-preserving treatment of patients with sarcoma of the extremities.

Aged↗
PubMed2003

Hypoxia attenuates the expression of E-cadherin via up-regulation of SNAIL in ovarian carcinoma cells.

Since ovarian carcinoma cells detach from the primary lesion and metastasize via peritoneal dissemination, we hypothesized that these cells are exposed to hypoxia, which may affect cell attachment and invasiveness. To address this hypothesis, we first examined in vivo the immunohistochemical expression of hypoxia-inducible factor-1alpha (HIF-1alpha) and its topological correlation with E-cadherin expression in ovarian carcinomas. We then examined in vitro the effect of hypoxia on the mRNA and protein expressions of E-cadherin using two ovarian cancer cell lines, SKOV3 and OVCAR3, and normal ovarian surface epithelial (OSE) cells. In addition, hypoxia-induced change in the expression of SNAIL, a transcriptional factor repressing E-cadherin expression, was also analyzed. Finally, we examined the facilitation of invasiveness of ovarian cancer cells under hypoxia using Matrigel invasion assay. Immunohistochemically, nuclear localization of HIF-1alpha was observed in 32 of the 76 (42%) carcinomas studied, and showed a topological correlation with loss of E-cadherin expression. Northern blotting, real-time PCR and Western blotting demonstrated that E-cadherin expression was remarkably decreased under hypoxia in both SKOV3 and OVCAR3 cells, but not in normal OSE cells. mRNA expression of SNAIL was increased under hypoxia in both ovarian cancer cell lines. Invasion assay revealed that hypoxia increases the invasiveness of ovarian cancer cells. Accordingly, the present study demonstrated that hypoxia induces down-regulation of E-cadherin in ovarian carcinoma cells, via up-regulation of the transcriptional repressor SNAIL. These findings suggest that hypoxia plays an important role in the change in intercellular attachment, which may be involved in the initiation of tumor progression of ovarian cancer cells.

Cadherins↗
PubMed2003

Toward understanding the natural history of ovarian carcinoma development: a clinicopathological approach.

OBJECTIVE: The natural history of the development of ovarian carcinoma is not known. It also remains undetermined whether ovarian carcinomas develop from benign and/or borderline malignant tumors or arise de novo from the ovarian surface epithelium. METHODS: To address these issues clinicopathologically, we reviewed the clinical charts of 543 patients with epithelial ovarian carcinoma and 252 patients with borderline tumors who underwent laparotomy at seven hospitals and collected patients whose clinical and transvaginal ultrasonography (USG) findings for adnexal regions 12 months or fewer prior to the surgery were available. Histological slides of the resected specimens were reexamined concerning the diagnosis and histological grade, as well as the presence or absence of benign- or borderline-like lesions adjacent to the carcinoma. RESULTS: Forty-nine patients had had gynecological examination with transvaginal USG 12 months or fewer prior to laparotomy. Among them, 35 had carcinomas (11 serous, 6 mucinous, 8 clear cell, 10 endometrioid) and 14 had borderline tumors (8 serous, 6 mucinous). Of the 35 patients with carcinoma, 19 (54%) had been followed up for benign-appearing cysts or endometriotic cysts. In these cases, serial USG examinations revealed an increase in size and/or appearance of the solid part of the cyst. In the remaining 16 (46%), however, there had been no apparent abnormalities in USG, and such cases occurred most frequently for serous carcinomas. CONCLUSIONS: Our findings suggest that approximately half of ovarian carcinomas develop secondarily from preexisting, benign-appearing cysts or endometriotic cysts, whereas the remaining half seem to develop suddenly from a normal-appearing ovary. This appears to be consistent with two possible pathways of ovarian carcinoma development; adenoma-carcinoma sequence and de novo carcinogenesis.

Adult↗
PubMed2003

Up-regulation of small GTPases, RhoA and RhoC, is associated with tumor progression in ovarian carcinoma.

To clarify the role of small GTPases Rho in the biologic behavior of ovarian carcinoma, we first examined the mRNA expression of RhoA, RhoB, and RhoC in benign, borderline, and malignant ovarian tumors using RT-PCR and real-time RT-PCR. The expression and localization of RhoA protein were also analyzed by Western blotting and immunohistochemistry. Finally, we examined whether up-regulation of Rho enhances the invasiveness of ovarian cancer cells in vitro. Analysis of mRNA levels of the Rho family genes revealed that levels of both RhoA and RhoC were significantly higher in carcinomas than in benign tumors (RhoA, p = 0.0035; RhoC, p = 0.0006). According to histologic subtype, both RhoA and RhoC mRNA levels in serous carcinomas were significantly higher than those in other histologic types. With regard to the International Federation of Gynecological and Obstetrics stage classification, both of RhoA and RhoC mRNA levels were significantly higher in tumors of Stages III+IV than in those of Stages I+II (RhoA, p = 0.0200; RhoC, p = 0.0057). In addition, analysis of matched pairs of primary and disseminated lesions demonstrated that expression of both RhoA and RhoC mRNA was significantly higher in metastatic than in primary tumors. Examination of the protein level showed that expression of RhoA was also increased in advanced ovarian carcinomas, especially those of serous histology. Accordingly, we hypothesized that up-regulation of Rho GTPases plays an important role in the progression of ovarian carcinoma. Matrigel invasion assay using the ovarian cancer cell line, SKOV3, showed that up-regulation and activation after treatment with lysophosphatidic acid was associated with enhanced invasion of the cancer cells. This increase in invasiveness was suppressed by the addition of C3, a specific inhibitor of Rho. These findings suggest that up-regulation of Rho GTPases is important in the tumor progression of ovarian carcinoma and that Rho family proteins could be a molecular target in cancer therapy.

Base Sequence↗
PubMedDate not supplied

Down-regulation of estrogen receptor by the methylation of the estrogen receptor gene in endometrial carcinoma.

BACKGROUND: Human uterine endometrial carcinomas are composed of estrogen receptor (ER)-positve and ER-negative subgroups, though the mechanisms that down-regulate the ER expression are not understood. The present study was undertaken to examine the involvement of methylation of the ER gene on the ER status. MATERIALS AND METHODS: DNA was extracted from 25 cases of endometrial carcinoma. Polymerase chain reaction (PCR), using the extracted DNA and methylation-sensitive restriction enzymes (Hpa II, Hha I), was performed to detect the methylation of a CpG island in the ER (alpha) gene. The results were compared with the ER expression by immunostaining. RESULTS: In the 25 endometrial carcinomas, methylation at the Hpa II site, or at both the Hpa II and Hha I sites, was found in 6 cases, while methylation was not found in the remaining 19 cases. Immunohistochemically, 5 of the 6 methylation-positive cases were negative for ER, whereas 14 of the 19 methylation-negative cases were ER-positive (p=0.02). CONCLUSION: Methylation of the CpG island of the ER gene is inversely correlated with ER expression in a subset of endometrial carcinomas.

Carcinoma↗