Kazuhiro Takahashi

Yamagata University, Ямагата, Yamagata, Japan

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Publications (48)174.33 Total impact

  • Hizuru Yamatani, Kazuhiro Takahashi, Satoru Nagase
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    ABSTRACT: Sex hormones as estrogen, testosterone, dehydroepiandrosterone decline with age. Especially in women, bioavailable estrogen level rapidly decreases around the menopause. Estrogen acts against arteriosclerosis to vascular endothelial cells and vascular smooth muscle cells. The lack of estrogen with menopause accelerates arteriosclerosis that is the leading cause of cardiovascular diseases. The adipose distribution shifts from gluteo-femoral to abdominal depots after menopause, and it is well known that visceral obesity induce metabolic syndrome, which is also high risk state for cardiovascular disease. Estrogen replacement therapy may reduce the cardiovascular risk, and we should pay attention to the starting age of women who undergo hormone therapy.
    Nippon rinsho. Japanese journal of clinical medicine 04/2015; 73(4):565-70.
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    ABSTRACT: During the dissemination of ovarian cancer cells, the cells float in the peritoneal cavity without access to a vascular supply and so are exposed to hypoxic conditions, which may cause the ovarian cancer cells to acquire a more aggressive and malignant phenotype. In this study, we screened microRNAs (miRNAs) to identify those that displayed altered expression patterns under hypoxic conditions and then analyzed their functional roles in ovarian cancer progression. miRNA PCR arrays performed on cells from 2 ovarian cancer cell lines (CaOV3 and RMUG-S) revealed miR-199a-3p as one of the miRNAs that are downregulated under hypoxia. In silico analyses indicated that MET is one of the target genes for miR-199a-3p; subsequently, miR-199a-3p expression was found to be inversely correlated with c-Met expression in ovarian cancer. Transfection of precursor miR-199a-3p into ovarian cancer cells reduced c-Met expression and inhibited the phosphorylation of c-Met, extracellular signal-regulated kinase, and AKT; in addition, proliferation, adhesion, and invasiveness were inhibited. Moreover, overexpression of miR-199a-3p in cancer cells significantly suppressed peritoneal dissemination in a xenograft model. In summary, the hypoxia-related microRNA miR-199a-3p drastically inhibits ovarian cancer progression through the downregulation of c-Met expression. Therefore, miR-199a-3p is a potential target for treating ovarian cancer dissemination.
    Oncotarget 03/2015; · 6.63 Impact Factor
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    ABSTRACT: Mayer-Rokitansky-Küster-Hauser syndrome is a rare congenital anomaly characterized by congenital aplasia or hypoplasia of the uterus and vagina. We report a case of Mayer-Rokitansky-Küster-Hauser syndrome with multiple large pelvic masses diagnosed by three-dimensional computed tomography (CT) angiography. A 40-year-old woman with Mayer-Rokitansky-Küster-Hauser syndrome presented with an abdominal mass that had grown for 3 months. Magnetic resonance imaging (MRI) confirmed several solid masses, and normal bilateral ovaries were detected; three-dimensional CT revealed that these tumors were supplied from the right ovarian and uterine arteries, suggesting that they arose from the uterus. Accordingly, leiomyoma was suspected. Laparoscopic surgery was contraindicated, and the patient therefore underwent laparotomy. The masses were resected with the bilateral rudimentary uteri and fallopian tubes, and pathologic evaluation confirmed leiomyoma. Combined MRI and three-dimensional CT angiography can accurately evaluate the origin and anatomic properties of leiomyomas in patients with Mayer-Rokitansky-Küster-Hauser syndrome.
    Obstetrics and Gynecology 01/2015; 125(2). DOI:10.1097/AOG.0000000000000646 · 4.37 Impact Factor
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    ABSTRACT: The Wilms' tumor 1 gene WT1 encodes a zinc transcription factor involved in a variety of cancer-related processes. In this study, we sought to investigate the effects of WT1 splice variants on tumorigenic activity and survival in an in vivo ovarian cancer model. To this end, we established stable ovarian cancer cell lines transduced with lentiviral constructs containing each of the four WT1 splice variants (− 17AA/− KTS, + 17AA/− KTS, − 17AA/+ KTS, and + 17AA/+ KTS). In mice inoculated intraperitoneally with SKOV3ip1 cells expressing WT1 − 17AA/− KTS, disseminated tumor weights and production of ascites were significantly increased compared with those in mice inoculated with cells expressing the control vector. The overall survival in mice inoulated with WT1 − 17AA/− KTS-expressing cells was significantly shorter than that in mice inoculated with control cells (P = .0115). Immunoblot analysis revealed that WT1 − 17AA/− KTS significantly increased the expression of vascular endothelial growth factor (VEGF) compared with the control. Greater numbers of CD31-immunopositive vessels were observed in tumors from mice injected with cells expressing WT1 − 17AA/− KTS than in tumors from control mice. Finally, WT1 − 17AA/− KTS significantly increased tumor microvessel density compared with that in the control (P < .05). Treatment with anti-VEGF antibody (bevacizumab) inhibited tumor growth, dissemination, and ascites production in mice injected with cells expressing WT1 − 17AA/− KTS. The overexpression of WT1 − 17AA/− KTS induced a more aggressive phenotype in ovarian cancer cells through VEGF up-regulation in an in vivo ovarian cancer model. Our findings indicated that WT1 − 17AA/− KTS enhanced tumorigenic activity and could decreased patient survival through up-regulation of VEGF expression in ovarian cancers.
    Translational oncology 10/2014; 7(5):580–589. DOI:10.1016/j.tranon.2014.07.008 · 3.40 Impact Factor
  • Hiromi Ishida, Kazuhiro Takahashi, Hirohisa Kurachi
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    ABSTRACT: A pregnancy that is complicated by a uterine prolapse is rare and primarily occurs in multiparous women during their first or second trimester. In the present report, we describe a case of a 31-year-old nulliparous woman who experienced sudden uterine prolapse at 38 weeks' gestation without labor pains. The cervix was congested, the cervical mucosa was partially lacerated, and bleeding was noted; the protruding cervix could not be repositioned into her vagina. Although the cervical congestion worsened over time, she still did not experience any labor pains. She was delivered by emergency cesarean section. Following delivery, the prolapse promptly improved and did not recur before her 1-month postpartum examination. To our knowledge, this is the first case where uterine prolapse occurred in a nulliparous woman during late gestation.
    International Urogynecology Journal 07/2014; DOI:10.1007/s00192-014-2457-z · 2.16 Impact Factor
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    ABSTRACT: The objective of this study was to investigate the chemotherapeutic agents that produce the strongest synergistic effects when combined with trabectedin against ovarian clear cell carcinoma (CCC), which is regarded as an aggressive chemoresistant histological subtype.
    International Journal of Gynecological Cancer 06/2014; 24(5):829-37. DOI:10.1097/IGC.0000000000000143 · 1.95 Impact Factor
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    ABSTRACT: Aim: The aim of the present study was to evaluate the correlation between WT1 expression levels and clinical features, to investigate the prognostic value of WT1 expression and to use lentiviral constructs to examine whether overexpression of WT1 affects cell proliferation and invasion in ovarian cancer patients. Real-time quantitative PCR (qPCR) methods were employed to analyze WT1 expression levels in clinical samples from 63 patients with ovarian cancer. The correlation between the copy number of WT1 mRNA and clinical variables was analyzed. The median copy number of WT1 mRNA was 53.94 (range=2.135-32,257) in all subjects and WT1 expression levels were found significantly increased in patients with a higher stage cancer (p<0.05), lymphnode (p<0.001) and omentum metastasis (p<0.001), as well as ascites production (p<0.05), compared to patients lacking these clinical variables. No significant difference in WT1 expression levels were observed between patients with and without recurrence. The median disease-free survival time in patients with low WT1 expression levels was significantly longer (p=0.038) than that in patients with high WT1 expression. However, overall survival curves showed no statistically significant (p=0.457) differences between patients with high- and low-WT1 expression levels. An in vitro study revealed that WT1 over-expression enhanced cell proliferation and invasion in ovarian cancer cells transduced with lentiviral constructs. Using qPCR, we found that high levels of WT1 expression correlated with aggressive clinical features in ovarian cancer. High WT1 expression may impact on median disease-free survival in ovarian cancer.
    Anticancer research 05/2014; 34(5):2331-40. · 1.87 Impact Factor
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    ABSTRACT: Intrauterine infection is still a common trigger of preterm delivery (PTD) and also a determinant risk factor for the subsequent development of neurodevelopmental abnormalities in neonates. In this study, we examined the expressional pattern of various inflammatory cytokines such as interleukin-1β (IL-1β), IL-6 and tumor necrosis factor-α (TNF-α) in placentae complicated with severe chorioamnionitis (CAM) and found that IL-6 is mainly expressed in macrophages in villous mesenchyme by immunohistochemical analysis with anti-CD-68 antibody. Using an experimental lipopolysaccharide (LPS)-induced preterm delivery model, the therapeutic potential of targeting this cytokine was investigated. Anti-IL-6 receptor antibody (MR16-1) was delivered 6 h before LPS treatment. Mice in the MR16-1 group had a significantly lower rate of preterm delivery (17%) than in the controls (53%,P=0.026). As a result, MR16-1 treatment significantly prolonged the gestational period (control; 18.4±1.7d, MR16-1; 19.8±1.5d, P =0.007) without any apparent adverse events on the mice and their pups. In primary human amniotic epithelial cells, pre-treatment with a humanized anti-human IL-6 receptor antibody, tocilizumab, significantly inhibited the production of prostaglandin E2 induced by IL-6. In conclusion, IL-6 was strongly expressed mainly in macrophages in villous mesenchyme in placentae complicated with CAM. Anti-IL-6R antibody significantly decreased the rate of preterm delivery in LPS-induced inflammatory model in mice, and inhibited PGE2 production from human primary amniotic epithelial cells. Targeting IL-6 signaling could be a promising option for the prevention of preterm delivery and needs to be further explored for future clinical application.
    Molecular Human Reproduction 08/2013; DOI:10.1093/molehr/gat057 · 3.48 Impact Factor
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    ABSTRACT: Objective:We investigated whether the estrogen released from non-sex cord-stromal ovarian tumors has biological effects on bone and endometrial tissue in postmenopausal women.Materials and Methods:A total of 132 patients with malignant (n = 112) or benign (n = 20) gynecological disease with normal postmenopausal ovaries were recruited as a control group (group C). The 75 patients with ovarian tumors were divided into 2 groups: group L (serum estradiol [E2] level of < 20 pg/ml; n = 42) and group H (serum E2 level of > 20 pg/ml; n = 33). The subjects' serum E2 levels, bone mineral density, urinary levels of the N-telopeptide of type I collagen, and serum levels of bone-specific alkaline phosphatase were measured before and after surgery. Histological examinations of the endometrium were carried out in the 75 patients with non-sex cord-stromal ovarian tumors.Results:High serum E2 levels were detected in 33 (44%) of 75 patients with ovarian tumors. The serum E2 levels of group H were significantly decreased after surgery. In the other subjects, there were no significant differences between the serum E2 levels observed before and after surgery. The mean preoperative N-telopeptide of type I collagen and bone-specific alkaline phosphatase levels of group H were significantly lower than those of group C. The bone mineral density values of groups L and H were significantly decreased after surgery. Five (6.7%) of 75 patients with non-sex cord-stromal ovarian tumors displayed abnormal endometrial histology, including 4 patients with grade 1 endometrioid cancer.Conclusions:The E2 released from ovarian tumors might have biological effects on bone metabolism and the incidence of abnormal endometrial histology.
    The Journal of Clinical Endocrinology and Metabolism 06/2013; 98(7). DOI:10.1210/jc.2013-1267 · 6.31 Impact Factor
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    ABSTRACT: OBJECTIVE: Visceral fat accumulation and metabolic syndrome incidence among women increase after menopause; therefore, fat metabolic changes and fat redistribution may occur according to menstrual status. The aim of our study was to clarify differences in subcutaneous and visceral adipose tissue metabolism between premenopausal and postmenopausal women, using metabolomics. METHODS: Thirty-nine (16 premenopausal and 23 postmenopausal) women were recruited through elective gynecologic surgery, and both subcutaneous and visceral adipose tissues were collected during surgical operation. Metabolite profiling of adipose tissue was performed by capillary electrophoresis with electrospray ionization time-of-flight mass spectrometry. RESULTS: Sedoheptulose 7-phosphate, a midproduct of the pentose phosphate pathway, was significantly higher (P < 0.05) in visceral adipose tissues of premenopausal women. Dihydroxyacetone phosphate and fructose-1,6-biphosphate, midproducts of glycolysis, were significantly higher (P < 0.05) in subcutaneous adipose tissues of postmenopausal women. The concentrations of fatty acid metabolites-heptanoate (C7:0; premenopausal vs postmenopausal, 4.07 [0.72] vs 2.64 [0.28] nmol/g), octanoate (C8:0; 3.52 [0.29] vs 5.20 [0.29] nmol/g), and pelargonate (C9:0; 8.03 [0.49] vs 10.66 [0.44] nmol/g)-in the visceral fat (but not in subcutaneous fat) of postmenopausal women were significantly higher (P < 0.05) than those in the visceral fat of premenopausal women. CONCLUSIONS: Fatty acid metabolites increase in visceral fat (but not in subcutaneous fat) after menopause. The change in fatty acid metabolism in visceral adipose tissues might be related to metabolic syndrome in postmenopausal women.
    Menopause (New York, N.Y.) 06/2013; DOI:10.1097/GME.0b013e318296431a · 2.81 Impact Factor
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    ABSTRACT: OBJECTIVE: The aim of this study is to clarify the association between estrogen and glucocorticoid levels in adipose tissues of premenopausal and postmenopausal women. METHODS: Forty (15 premenopausal and 25 postmenopausal) women aged 22 to 79 years were recruited through elective gynecological surgical operation, and both subcutaneous and visceral fat were collected during the surgical operation. Messenger RNA (mRNA) expressions of 11β hydroxysteroid dehydrogenase type 1 (HSD1), which catalyzes cortisone to cortisol, and 17β-HSD1 and 17β hydroxysteroid dehydrogenase type 2 (HSD2), which catalyze the interconversion of estrone (E1) and estradiol (E2), were measured by real-time reverse transcription polymerase chain reaction. The levels of E1, E2, cortisol, and cortisone in adipose tissues were measured by liquid chromatography tandem mass spectrometry. RESULTS: The visceral fat area was significantly increased (P < 0.01) in postmenopausal women compared with that in premenopausal women. The cortisol/cortisone ratio (P < 0.01) and the expression of 11β-HSD1 mRNA (P < 0.001) in visceral fat, but not in subcutaneous fat, in postmenopausal women were significantly higher than those in premenopausal women. There was a significant correlation (r = 0.69, P < 0.05) between the E1/E2 ratio of visceral fat and body mass index in postmenopausal women. A significant correlation (r = 0.54, P < 0.05) between the cortisol/cortisone ratio and the E1/E2 ratio of visceral fat was observed in postmenopausal women. CONCLUSIONS: The expression of 11β-HSD1 mRNA in visceral fat increases in postmenopausal women, and the E1/E2 ratio in visceral fat may be associated with local glucocorticoid levels after menopause.
    Menopause (New York, N.Y.) 11/2012; 20(4). DOI:10.1097/gme.0b013e318271a640 · 2.81 Impact Factor
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    ABSTRACT: We examined the effect of gefitinib (ZD1839), a selective epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor, on cytotoxicity to cisplatin, EGFR downstream signaling, apoptosis and the association between the inhibition of DNA repair by gefitinib and the expression of DNA-dependent protein kinase (DNA-PK) using three ovarian cancer cell lines. In the presence of gefitinib, cisplatin-induced growth inhibition and apoptosis were significantly enhanced in Caov-3 and RMG-1 cells, which express EGFR, and in A2780, which lacks EGFR but expresses HER-2. Gefitinib significantly inhibited the cisplatin-induced ERK and Akt activation in Caov-3 and RMG-1 cells but not in A2780 cells. In all three cell lines, there was delayed repair of DNA intrastrand cross-links damaged by cisplatin used in combination with gefitinib, compared with cisplatin alone. The reduction in DNA-PK levels persisted when cells were exposed to combinations of cisplatin and gefitinib in all cell lines. Moreover, the delayed repair was cancelled by anti-HER2 small-interfering RNA transfection in A2780 cells. These results suggest that combination therapy with cisplatin and gefitinib may increase the therapeutic efficacy of cisplatin by blocking EGFR downstream signaling and/or inhibiting DNA repair in ovarian cancer.
    Cancer biology & therapy 04/2012; 13(6):408-16. DOI:10.4161/cbt.19292 · 3.63 Impact Factor
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    ABSTRACT: Rho, a Ras-related small GTPase, and Rho-associated coiled coil-containing protein kinase (Rho kinase, ROCK1 and ROCK2) are key regulators of focal adhesion, actomyosin contraction, and thus cell motility. Rho/ROCK kinases also play roles in proliferation, differentiation, apoptosis and oncogenic transformation. In the present study, we have shown that Rho/ROCK pathway inhibition by fasudil, an orally administered inhibitor of Rho kinases, enhanced cisplatin-induced growth inhibition and apoptosis in human ovarian cancer cell lines. Fasudil inhibited hypoxia inducible factor (HIF)-1α protein expression. Knockdown of RhoA, ROCK1 or ROCK2 also attenuated the expression of HIF-1α. Furthermore, knockdown of HIF-1α using small interfering RNA enhanced cisplatin-induced growth inhibition and apoptosis as did inhibition of the Rho/ROCK pathway by fasudil, the Rho/ROCK inhibitor Y27632, or by Rho/ROCK knockdown. Therefore, the Rho/ROCK pathway may modulate HIF-1α signal transduction and blockade of Rho/ROCK enhances the efficacy of cisplatin by inhibiting HIF-1α in ovarian cancer cells. Our findings suggested that the Rho/ROCK pathway may be a new target for molecular targeting therapies against ovarian cancer.
    Cancer biology & therapy 01/2012; 13(1):25-33. DOI:10.4161/cbt.13.1.18440 · 3.63 Impact Factor
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    ABSTRACT: Estrogen (E2) has direct in vivo and in vitro effects, such as inducing neurite outgrowth, on neurons. We investigated the morphological changes and intracellular signaling pathway induced by E2 in neuroblastoma (SH-SY5Y) cells. The effect of medroxyprogesterone acetate (MPA) or progesterone (P4) on the E2-induced neurite outgrowth was also examined using SH-SY5Y cells. Neurite outgrowth was induced by E2 in association with the phosphorylation of Akt, and these effects of E2 were abolished by MPA but not by P4. Progesterone receptor antagonist RU486 blocked the inhibitory effects of MPA. Estrogen receptor antagonist ICI 182,780 and phosphatidylinositol 3-kinase inhibitor LY294002 inhibited the E2-induced neurite outgrowth. Because the Rho family of small GTPases has been shown to be involved in the regulation of neurite outgrowth, we examined the cross-talk among Rac1, Cdc42 and RhoA in the E2-induced neurite outgrowth. E2 immediately increased the Rac1 and Cdc42 activity and decreased the RhoA activity. E2-induced neurite outgrowth was attenuated in cells expressing dominant-negative mutants for Rac1 or Cdc42. These results suggest that regulation of Rho family GTPase activity by E2 is important for the neurite outgrowth in neuroblastoma cells, and that MPA may have an antagonistic effect against E2.
    Molecular and Cellular Neuroscience 08/2011; 48(3):217-24. DOI:10.1016/j.mcn.2011.08.002 · 3.73 Impact Factor
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    ABSTRACT: The objective of this study was to evaluate the antitumor efficacy of trabectedin in clear cell carcinoma (CCC) of the ovary, which is regarded as an aggressive, chemoresistant, histologic subtype. Using 6 human ovarian cancer cell lines (3 CCC and 3 serous adenocarcinomas), the antitumor effects of trabectedin were examined in vitro, and we compared its activity according to histology. We next examined the antitumor activity of trabectedin in both cisplatin-resistant and paclitaxel-resistant CCC cells in vitro. Then, the in vivo effects of trabectedin were evaluated using mice inoculated with CCC cell lines. Using 2 pairs of trabectedin-sensitive parental and trabectedin-resistant CCC sublines, we investigated the role of mTOR in the mechanism of acquired resistance to trabectedin. Finally, we determined the effect of mTOR inhibition by everolimus on the antitumor efficacy of trabectedin in vitro and in vivo. Trabectedin showed significant antitumor activity toward chemosensitive and chemoresistant CCC cells in vitro. Mouse xenografts of CCC cells revealed that trabectedin significantly inhibits tumor growth. Greater activation of mTOR was observed in trabectedin-resistant CCC cells than in their respective parental cells. The continuous inhibition of mTOR significantly enhanced the therapeutic efficacy of trabectedin and prevented CCC cells from acquiring resistance to trabectedin. Trabectedin is a promising agent for CCC as a first-line chemotherapy and as a second-line treatment of recurrent CCC that had previously been treated with cisplatin or paclitaxel. Moreover, trabectedin combined with everolimus may be more efficacious for the management of CCC.
    Clinical Cancer Research 06/2011; 17(13):4462-73. DOI:10.1158/1078-0432.CCR-10-2987 · 8.19 Impact Factor
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    ABSTRACT: We aimed to clarify which steroid receptor is involved in the inhibitory effect of medroxyprogesterone acetate (MPA) on estrogen-induced endothelial nitric oxide synthase (eNOS) phosphorylation in human umbilical vein endothelial cells (HUVEC). The progesterone/glucocorticoid receptor (GR) antagonist RU-486 and introduction of GR siRNA caused attenuation of the inhibitory effect of MPA on the estrogen-induced eNOS phosphorylation and eNOS activity in HUVEC.
    Fertility and sterility 11/2010; 95(3):1168-70. DOI:10.1016/j.fertnstert.2010.09.041 · 4.30 Impact Factor
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    ABSTRACT: We investigated the effects of dienogest (DNG), which has a profile similar to that of natural progesterone (P4), on the favorable effects of estrogen in endothelial function. (1) Human umbilical vein endothelial cells were treated with medroxyprogesterone acetate (MPA), DNG, or P4 with or without estradiol (E2), and then we examined nitric oxide (NO) production, phosphorylation of Akt, ERK, and endothelial NO synthase. (2) Twenty women with surgical menopause were randomly allocated to four groups: control (no treatment), E2 alone, E2 + MPA, and E2 + DNG. The treatment groups were treated with transdermal E2 (0.72 mg) for 2 days or E2 + MPA (2.5 mg/d) or E2 + DNG (2 mg/d) for a week starting 1 week after the operation; the control group did not use hormone. We examined the changes in the flow-mediated dilatation (FMD) of the brachial artery using ultrasonography. (1) Although MPA attenuated E2-induced NO production and phosphorylation of Akt, extracellular signal-regulated kinase, and endothelial NO synthase, neither DNG nor P4 inhibited E2 effects. (2) A significant decrease in FMD was observed 1 week after the operation in all groups. E2 significantly ameliorated endothelial impairment (FMD, 3.4% +/- 0.9% to 7.6% +/- 1.3%) in the E2-alone group (P < 0.05), but E2 + MPA could not ameliorate endothelial impairment (3.3% +/- 1.1% to 3.5% +/- 1.0%). However, FMD in the E2 + DNG group significantly increased (2.9% +/- 0.5% to 8.7% +/- 1.0%; P < 0.05). These results suggest that DNG did not inhibit the restoration of vasodilatation by E2. DNG may have an advantage compared with MPA on the endothelial function in postmenopausal women receiving hormone therapy.
    Menopause (New York, N.Y.) 04/2010; 17(3):615-21. DOI:10.1097/gme.0b013e3181d273c7 · 2.81 Impact Factor
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    ABSTRACT: We examined the molecular mechanisms of the antiestrogenic effects of clomiphene citrate (CC) in the endometrium using two types of cell lines, Ishikawa and EM-E6/E7/hTERT cells. CC or ICI182780 inhibited 17beta-estradiol (E2)-induced endometrial cell proliferation and transcriptional activation of the estrogen response element (ERE) gene. We directly visualized the ligand-estrogen receptor (ER)alpha interaction using green fluorescent protein (GFP)-tagged ER alpha in a single living cell. Whereas E2 changed the nuclear localization of GFP-ER alpha to a punctate distribution within 5 min, CC or ICI182780 changed the slower and less mobilization of GFP-ER alpha compared with E2. Pretreatment with CC or ICI182780 partly prevented the E2-induced nuclear redistribution of GFP-ER alpha. Fluorescence recovery after photobleaching revealed that GFP-ER alpha mobility treated with E2 was more rapid than that treated by CC or ICI182780. As coactivator recruitment to the ER is essential for ER-dependent transcription, we examined the interaction between ER alpha and steroid receptor coactivator-1 (SRC-1). The complex formation between ER alpha and SRC-1 was significantly increased by E2 but was prevented in the presence of CC or ICI182780 by coimmunoprecipitation. Moreover, the E2-induced colocalization of GFP-ER alpha and SRC-1 was prevented in the presence of CC or ICI182780 according to an immunofluorescence assay. We also observed that the reduction of SRC-1 using small interfering RNA for SRC-1 resulted in the inhibition of E2-induced cell proliferation and transcriptional activation of the ERE gene. Collectively, these results suggest that CC may inhibit E2-induced endometrial epithelial cell proliferation and ERE transactivation by inhibiting the recruitment of SRC-1 to ER alpha.
    Endocrinology 11/2009; 151(1):394-405. DOI:10.1210/en.2009-0721 · 4.64 Impact Factor
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    ABSTRACT: Estrogen has both rapid and longer term direct effects on cardiovascular tissues mediated by the two estrogen receptors, ESR1 and ESR2. Previous work identified that estrogen regulates the expression of inducible nitric oxide synthase (NOS2A) in vascular smooth muscle cells (VSMC). ESR2 knockout mice have vascular dysfunction due to dysregulation of NOS2A expression and these mice are hypertensive (Zhu et al. Science 2002 295 505-508). Here, we report studies to examine the differential regulation of NOS2A gene expression by ESR1 and 2. Immunoblotting and RT-PCR studies revealed that different VSMC lines expressed different levels of ESR1 and ESR2 protein and mRNA. VSMC from different vascular beds were studied, including aortic VSMC expressing ESR1 and radial (Rad) VSMC expressing ESR2. E(2) inhibited NO production and NOS2A protein expression in aortic VSMC. Human NOS2A promoter-reporter studies revealed suppression of NOS2A reporter activity by E(2) in aortic VSMC, and stimulation of NOS2A reporter activity by E(2) in Rad arterial VSMC. In heterologous expression studies of COS-7 cells lacking endogenous ER, E(2) treatment of COS-7 cells did not alter NOS2A reporter activity in the presence of ESR1, while reporter activity increased 2.3-fold in the presence of ESR2. Similar experiments in COS-7 cells using the selective estrogen receptor modulator raloxifene showed that raloxifene caused a reduction in NOS2A reporter activity with ESR1 coexpression and an increase with ESR2 coexpression. Rat VSMC expressing ESR2 but not ESR1 also showed increased NOS2A reporter activity with E(2) treatment, an effect lost when ESR1 was introduced into the cells. Taken together, these data support that hNOS2A transcription is regulated positively by ESR2 and negatively by ESR1 in VSMC, supporting differential actions of these two estrogen receptors on a physiologically relevant gene in VSMC.
    Journal of Endocrinology 09/2008; 199(2):267-73. DOI:10.1677/JOE-07-0292 · 3.59 Impact Factor
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    ABSTRACT: Hypoxic response of endothelial cells (EC) is an important component of tumor angiogenesis. Especially, hypoxia-inducible factor-1 (HIF-1)-dependent EC-specific mechanism is an essential component of tumor angiogenesis. Recently, the Rho/Rho-associated kinase (ROCK) signaling has been shown to play a key role in HIF-1alpha induction in renal cell carcinoma and trophoblast. The present study was designed to investigate whether low oxygen conditions might modulate HIF-1alpha expression through the Rho/ROCK signaling in human umbilical vascular ECs (HUVEC). Pull-down assay showed that hypoxia stimulated RhoA activity. Under hypoxic conditions, HUVECs transfected with small interfering RNA of RhoA and ROCK2 exhibited decreased levels of HIF-1alpha protein compared with nontargeted small interfering RNA transfectants, whereas HIF-1alpha mRNA levels were not altered. One of ROCK inhibitors, fasudil, inhibited hypoxia-induced HIF-1alpha expression without altering HIF-1alpha mRNA expression. Furthermore, proteasome inhibitor prevented the effect of fasudil on HIF-1alpha expression, and polyubiquitination was enhanced by fasudil. These results suggested that hypoxia-induced HIF-1alpha expression is through preventing HIF-1alpha degradation by activating the Rho/ROCK signaling in ECs. Furthermore, hypoxia induced both vascular endothelial growth factor (VEGF) and VEGF receptor-2 expression through the Rho/ROCK/HIF-1alpha signaling in HUVECs. Thus, augmented VEGF/VEGF receptor-2 autocrine mechanism stimulated HUVEC migration under hypoxic conditions. In summary, the Rho/ROCK/HIF-1alpha signaling is an essential mechanism for hypoxia-driven, VEGF-mediated autocrine loop in ECs. Therefore, fasudil might have the antimigratory effect against ECs in tumor angiogenesis.
    Molecular Cancer Therapeutics 07/2008; 7(6):1551-61. DOI:10.1158/1535-7163.MCT-07-0428 · 6.11 Impact Factor

Publication Stats

1k Citations
174.33 Total Impact Points


  • 2003–2015
    • Yamagata University
      • Department of Obstetrics and Gynecology
      Ямагата, Yamagata, Japan
  • 2013
    • Keio University
      • Institute for Advanced Biosciences
      Edo, Tōkyō, Japan
  • 2003–2013
    • Osaka City University
      • Department of Obstetrics and Gynecology
      Ōsaka, Ōsaka, Japan
  • 2010
    • Dokkyo Medical University
      • Department of Obstetrics and Gynecology
      Tochigi, Tochigi-ken, Japan
  • 2002
    • Osaka University
      • Division of Obstetrics and Gynecology
      Suika, Ōsaka, Japan