Biomedical subjects

Hirotaka Nishi

Publications and source records attributed to Hirotaka Nishi.

17 recordsLinked to original sources

PubMed2026

Survey on the current status of novel cancer drug therapies for gynecological cancers in Japan: a nationwide survey by the Japan Society of Obstetrics and Gynecology (JSOG).

OBJECTIVE: To characterize real-world implementation of novel therapies in gynecological oncology in Japan and identify actionable gaps through a nationwide survey. METHODS: A cross-sectional questionnaire was distributed to Japan Society of Obstetrics and Gynecology-affiliated institutions. The items covered institution characteristics; use of poly (ADP-ribose) polymerase (PARP) inhibitors, immune checkpoint inhibitors (ICIs), kinase inhibitors, and antibody-based agents; local adverse event (AE) manuals; availability of expert panels and immune-related adverse event (irAE) teams; and perceptions of educational sufficiency. RESULTS: Valid responses were obtained from 245 institutions, spanning universities, cancer centers, and general hospitals. Most institutions reported the routine use of PARP inhibitors, ICIs, kinase inhibitors, and antibody drugs. However, only 40.4% of institutions had an in-hospital irAE management team, 57.1% had an AE/irAE manual, and 31.0% and 12.2% considered prior educational opportunities sufficient for physicians and nurses/other medical staff, respectively. High-volume institutions and academic centers were significantly more likely to have medical oncology support, expert-panel access, irAE teams, manuals, and higher self-rated evidence-based management capacity. The majority favored e-learning and society-led case conferences, and 76.3% supported the development of drug therapy subspecialties in gynecologic oncology. CONCLUSION: Innovative drug modalities are widely implemented across Japanese gynecological oncology services. However, critical gaps persist in multidisciplinary irAE management, standardized manuals, and practical education. Coordinated society-led programs to expand irAE teams, streamline companion diagnostics, disseminate ready-to-use algorithms, and provide credential-targeted training may enhance safety, equity, and evidence-concordant care nationwide.

Immune Checkpoint Inhibitors↗

PubMed2006

Spontaneous delivery is related to barometric pressure.

BACKGROUND: Many studies have shown that changes in the weather affect health. In the field of obstetrics and gynecology, several events have been empirically shown to be related to the weather. Labor pain is controlled by the autonomic nervous system and various hormones, and is expected to be influenced by the weather and environmental changes. Several studies have been conducted on the relationship between delivery and barometric pressure, which shows constant changes with changes in weather, but there is no generally accepted view on this. METHODS: We conducted a retrospective study in our patients who had a spontaneous cephalic delivery in this hospital between January 1997 and December 2003, in order to determine whether low barometric pressure induces labor pains, premature rupture of the membranes, and delivery, and whether changes in barometric pressure affect delivery. RESULTS: There was a significant increase in the number of deliveries and rupture of the membranes at low barometric pressure (P < 0.01), although there was no significant correlation between onset of labor and barometric pressure. This tendency was noted in both women with spontaneous rupture of the fetal membranes and those with premature rupture of the membranes (P < 0.01). On days with a larger change in barometric pressure, regardless of whether it was increasing or decreasing, the number of deliveries increased and the relationship was statistically significant (P < 0.01). CONCLUSIONS: A causal relationship was noted between the number of rupture of the fetal membranes, delivery and barometric pressure, suggesting that low barometric pressure induces rupture of the fetal membranes and delivery.

Adolescent↗

PubMed2006

Expression of stathmin in human uterus and decidualizing endometrial stromal cells.

The cytosolic phosphoprotein stathmin is upregulated at the site of embryo implantation in the rodents. However, stathmin expression in the human uterus has not yet been investigated. The distribution of uterine and placental stathmin was analyzed by immunohistochemistry, while stathmin mRNA expression was detected in endometrial tissues by the reverse transcriptase-PCR. Cultured endometrial stromal cells were used to investigate whether stathmin plays a role in decidualization. Stathmin is expressed specifically in the glandular epithelium and the stromal cells of human endometrial tissue. It is also expressed by cytotrophoblasts and extravillous trophoblasts, but not by syncytiotrophoblasts or decidual tissues during the first trimester of pregnancy. When stromal cells isolated from normal endometrial tissues were cultured and stimulated to decidualize by progesterone (P4) plus estrogen or dibutyryl cyclic 3',5'-AMP, their total and phosphorylated stathmin levels decreased. Knocking down stathmin expression in the cultured stromal cells using small interfering RNA, before the cells were exposed to the decidualizing agents, significantly suppressed decidualization, as indicated by the decreased expression of IGF-binding protein-1 and prolactin. Stathmin is differently expressed in human endometrial and placental cells and may participate in the decidualization of endometrial stromal cells.

Blotting, Western↗

PubMed2004

Hypoxia-inducible factor-1 transactivates transforming growth factor-beta3 in trophoblast.

Hypoxia occurs during the development of placenta in the first trimester and is implicated in trophoblast differentiation. Intervillous blood flow increases after 10 wk of gestation and results in exposure of trophoblast cells to oxygen. Before this time, low oxygen appears to prevent trophoblast differentiation toward an invasive phenotype. The oxygen-regulated early events of trophoblast differentiation are mediated by TGF-beta3. TGF-beta3 plays a vital role in trophoblast differentiation, and its overexpression can be found in preeclamptic placenta. We sought to determine the mechanism of TGF-beta3 expression through hypoxia-inducible factor (HIF)-1. We show that HIF-1alpha and TGF-beta3 are overexpressed in preeclamptic placenta. Hypoxia not only transactivates the TGF-beta3 promoter activity but also enhances endogenous TGF-beta3 expression. Using the TGF-beta3 promoter deletion mutants, we show that the region between -90 and -60, which contains a putative HIF-1 consensus motif, is crucial for HIF-1-mediated transactivation. Electrophoretic mobility shift assays show that HIF-1 binds to the oligonucleotide containing the HIF-1 motif. Also, introduction of an antisense oligonucleotide for HIF-1 diminishes TGF-beta3 expression during hypoxia, indicating that the up-regulation of TGF-beta3 by hypoxia is mediated through HIF-1. Our results provide evidence that regulation of TGF-beta3 promoter activity by HIF-1 represents a mechanism for trophoblast differentiation during hypoxia.

Cell Line, Tumor↗

PubMed2004

Expression of a novel human gene, human wings apart-like (hWAPL), is associated with cervical carcinogenesis and tumor progression.

In Drosophila melanogaster, the wings apart-like (wapl) gene encodes a protein that regulates heterochromatin structure. Here, we characterize a novel human homologue of wapl (termed human WAPL; hWAPL). The hWAPL mRNA was predominantly expressed in uterine cervical cancer, with weak expression in all other normal and tumor tissues examined. hWAPL expression in benign epithelia was confined to the basal cell layers, whereas in dysplasias it increasingly appeared in more superficial cell layers and showed a significant correlation with severity of dysplasia. Diffuse hWAPL expression was found in all invasive squamous cell carcinomas examined. In addition, NIH3T3 cells overexpressing hWAPL developed into tumors on injection into nude mice. Furthermore, repression of hWAPL expression by RNA interference induced cell death in SiHa cells. These results demonstrate that hWAPL is associated with cell growth, and the hWAPL expression may play a significant role in cervical carcinogenesis and tumor progression.

Animals↗

PubMed2004

HIF-1-mediated activation of telomerase in cervical cancer cells.

Hypoxia-inducible factor 1 (HIF-1) is a key regulator of O(2) homeostasis, which regulates the expression of several genes linked to angiogenesis and energy metabolism. Tumor hypoxia has been shown to be associated with poor prognosis in a variety of tumors, and HIF-1 induced by hypoxia plays pivotal roles in tumor progression. The presence of putative HIF-1-binding sites on the promoter of human telomerase reverse transcriptase gene (hTERT) prompted us to examine the involvement of HIF-1 in the regulation of hTERT and telomerase in tumor hypoxia. The telomeric repeat amplification protocol (TRAP) assay revealed that hypoxia activated telomerase in cervical cancer ME180 cells, with peak induction at 24-48 h of hypoxia. Notably, hTERT mRNA expression was upregulated at 6-12 h of hypoxia, concordant with the elevation of HIF-1 protein levels at 6 h. hTERT protein levels were subsequently upregulated at 24 h and later. Luciferase assays using reporter plasmids containing hTERT core promoter revealed that hTERT transcription was significantly activated in hypoxia and by HIF-1 overexpression, and that the two putative binding sites within the core promoter are responsible for this activation. Chromatin immunoprecipitation assay identified the specific binding of HIF-1 to these sites (competing with c-Myc), which was enhanced in hypoxia. The present findings suggest that hypoxia activates telomerase via transcriptional activation of hTERT, and that HIF-1 plays a critical role as a transcription factor. They also suggest the existence of novel mechanisms of telomerase activation in cancers, and have implications for the molecular basis of hypoxia-induced tumor progression and HIF-1-based cancer gene therapy.

DNA-Binding Proteins↗

PubMed2004

Establishment of a HPV and p53-mutation-negative human cell line (CA) derived from a squamous carcinoma of the uterine cervix.

OBJECTIVE: Well-characterized human cancer cell lines are important research resources for studying cancer cell biology, as well as for developing new strategies against cancer cell growth and progression. We present a new cell line, CA, established from an invasive non-keratinizing squamous cell carcinoma of the uterine cervix in 36-year-old patient. METHODS: We measured the doubling time of CA cells. To investigate the tumorigenicity of CA, cells were inoculated subcutaneously into the back of nude mice. Several tumor markers were analyzed using culture media by EIA. PCR-based analyses were performed to examine the human papillomavirus (HPV) status and telomerase activity. CA was also screened for p53 mutation using the sequencing technique. RESULTS: The cells show rapid growth in culture with a doubling time of 14.3 h and high migration activity. Monolayer-cultured cells were polygonal, showing a pavement-like arrangement and a tendency to pile up without contact inhibition. Subcutaneous transplantation of the CA cells into nude mice formed solid tumors that were histologically diagnosed as squamous cell carcinoma, whereas no metastasis was observed. Cultured CA cells produced SCC, CEA, TPA, CA125 and SLX. Genetic and molecular analyses revealed high telomerase activity and the absence of HPV DNA. No p53 mutation was observed in this cell line. CONCLUSION: These properties suggest that CA is an aggressive cervical carcinoma cell line and may serve as a useful experimental model for studying HPV role in cervical carcinogenesis.

Adult↗

PubMed2004

Hypoxia-inducible factor 1 mediates upregulation of telomerase (hTERT).

Hypoxia occurs during the development of the placenta in the first trimester and correlates with both trophoblast differentiation and the induction of telomerase activity through hTERT expression. We sought to determine the mechanism of regulation of hTERT expression during hypoxia. We show that hypoxia-inducible factor 1alpha (HIF-1alpha) and hTERT expression in the human placenta decrease with gestational age and that these are overexpressed in preeclamptic placenta, a major complication of pregnancy. Hypoxia not only transactivates the hTERT promoter activity but also enhances endogenous hTERT expression. The hTERT promoter region between -165 and +51 contains two HIF-1 consensus motifs, and in vitro reporter assays show that these are essential for hTERT transactivation by HIF-1. Introduction of an antisense oligonucleotide for HIF-1 diminishes hTERT expression during hypoxia, indicating that upregulation of hTERT by hypoxia is directly mediated through HIF-1. Our results provide persuasive evidence that the regulation of hTERT promoter activity by HIF-1 represents a mechanism for trophoblast growth during hypoxia and suggests that this may be a generalized response to hypoxia in various human disorders including resistance to cancer therapeutics by upregulating telomerase.

Cell Division↗

PubMed2003

Matrix metalloproteinase-26 is expressed in human endometrium but not in endometrial carcinoma.

BACKGROUND: The human matrix metalloproteinase (MMP)-26, also called matrilysin-2 or endometase, has been isolated as a matrilysin (MMP-7) homolog. Matrix metalloproteinase-26 was expressed in tissue samples from the placenta and endometrial tumors and its expression may be related to the development of endometrial carcinomas. METHODS: Total RNAs were isolated from 5 endometrial carcinoma cell lines, 36 normal endometrial tissue samples, 4 hyperplasia tissue samples, and from 24 endometrial carcinoma tissue samples. Reverse transcription-polymerase chain reation (RT-PCR) was performed to detect MMP-26 mRNA expression. To identify MMP-26 mRNA localization and protein expression, we performed in situ RT-PCR and immunohistochemistry, respectively. RESULTS: Reverse transcription-polymerase chain reaction analysis revealed that MMP-26 mRNA was expressed in 24 of 36 normal human endometrial tissue samples. However, MMP-26 mRNA expression was not detected in endometrial carcinoma cell lines nor in endometrial carcinoma tissue samples except for one case. Western blot analysis showed similar results. In situ RT-PCR analysis revealed that MMP-26 expression was localized in the epithelial glandular cells but faint expression was observed in the stromal cells. Subsequently, we separated endometrial tissues into epithelial glandular and stromal cells. Using RT-PCR, the purified epithelial glandular cells exhibited MMP-26 mRNA expression but the purified stromal cells did not. Immunohistochemical analyses revealed that MMP-26 protein expression is also limited to endometrial epithelial glandular cells but not to cancer cells. Therefore, MMP-26 expression is limited to normal epithelial glandular cells. CONCLUSIONS: We found a significant difference in MMP-26 expression in normal and malignant endometrial tissue samples, although its function is still unknown. These data suggest that MMP-26 may be a candidate for a new tumor marker for endometrial carcinomas.

Blotting, Western↗

PubMed2003

Establishment of a new human cell line (EN) with TP53 mutation derived from endometrial carcinoma.

We present a new cell line, EN, established from an invasive endometrioid adenocarcinoma of the uterine corpus in 50-year-old patient. The cells show rapid growth in culture with a doubling time of 24.4 hours and high migration activity. Monolayer-cultured cells were polygonal in shape and showed a tendency to pile up without contact inhibition. Subcutaneous transplantation of the EN cells into nude mice formed solid tumors that were histologically diagnosed as adenocarcinoma, whereas no metastasis was observed. Cultured EN cells produced tissue polypeptide antigen. Genetic and molecular analyses revealed high telomerase activity and estrogen receptor beta but not alpha expression. Using the polymerase chain reaction-single strand conformation polymorphism technique, we have screened EN cells for TP53 mutation in exons 5-8. A mobility shift was observed in this cell line in exon 8. A nucleotide insertion (CGT-->CAGT) was detected at codon 273, which resulted in a creation of a stop codon at codon 308. This cell line thus appears to represent the development of a more malignant clone with divergent receptor function and growth behavior, and provides us with an interesting new tool for the study of tumorigenesis in the human endometrium.

Animals↗

PubMed2003

Analysis of the epidermal growth factor receptor promoter: the effect of nuclear factor-kappaB.

The epidermal growth factor receptor gene is highly regulated and responsive to extracellular stimuli that control cell growth. We have identified five putative nuclear factor-kappaB (NF-kappaB) binding sites within the epidermal growth factor receptor (EGFR) promoter region by sequence analysis. We have analyzed the potential role of NF-kappaB family members in the regulation of the EGFR transcription. Electrophoretic mobility shift analysis demonstrated that the p50 and p49, subunit proteins of the NF-kappaB, bound to the EGFR promoter at four out of five of these sites. However, it was found that NF-kappaB could not transactivate the EGFR by cotransfection experiments with each NF-kappaB subunit, using p50, p65 and c-Rel and an EGFR promoter luciferase reporter. Treatment of cells with tumor necrosis factor (TNF)-alpha, which could degrade the I-kappaB and then result in translocation of NF-kappaB to nucleus, did not enhance EGFR promoter reporter gene transcription. Also, TNF-alpha did not induce EGFR expression at the protein level. These results indicate that even though purified NF-kappaB can bind to the putative sites, there is no evidence that NF-kappaB transactivates the EGFR promoter region.

3T3 Cells↗

PubMed2002

Rupture of pregnant noncommunicating rudimentary uterine horn with fetal salvage: a case report.

A rare case of noncommunicating rudimentary uterine horn pregnancy is described. The pregnancy proceeded to twenty-six gestational weeks when the rudimentary uterine horn ruptured as the patient had signs and symptoms of massive hemoperitoneum. An emergency exploratory laparotomy revealed incomplete rupture of the gravid rudimentary horn. A viable female infant with a birth weight of 633 g was delivered. The rudimentary horn had no direct communication to the uterine cavity of the unicornate right uterus. Immunohistochemical examination showed that the excised uterine horn was filled with placental tissue without an intervening layer of decidua basalis.

Adult↗

PubMed2002

Early Growth Response-1 gene mediates up-regulation of epidermal growth factor receptor expression during hypoxia.

Hypoxia occurs during development of cancers and is correlated with cancer progression. Hypoxia also induces epidermal growth factor receptor (EGFR) expression. The EGFR plays a vital role in cell growth, and its overexpression can lead to transformation. We sought to determine the regulator(s) of EGFR expression during hypoxia. We demonstrate that early growth response factor 1 (Egr-1), which is induced by hypoxia, can activate the basal transcriptional activity of the EGFR promoter. Egr-1 not only transactivates the EGFR promoter activity but also enhances endogenous EGFR expression. Using a series of EGFR promoter deletion mutants, we show that the region between -484 and -389, which contains a putative Egr-1 consensus motif, is crucial for EGFR transactivation by Egr-1. Electrophoretic mobility shift assays show that Egr-1 binds to the oligonucleotide containing this Egr-1 motif. Also, introduction of an antisense oligonucleotide for Egr-1 diminishes EGFR expression during hypoxia, indicating that the up-regulation of EGFR by hypoxia is mediated through Egr-1. Our results provide evidence that regulation of EGFR promoter activity by Egr-1 represents a mechanism for epidermal cell growth during hypoxia.

Cell Hypoxia↗

PubMed2002

Establishment and characterization of a new human cell line (EJ) derived from endometrial carcinoma.

We present a new cell line, EJ established from an invasive endometrioid adenocarcinoma of the uterine corpus in a 56-year-old patient. The cells show rapid growth in culture with a doubling time of 16 h and high migration activity. Monolayer-cultured cells were polygonal in shape showing a tendency to pile up without contact inhibition. Subcutaneous transplantation of the EJ cells into nude mice formed solid tumors that were histologically diagnosed as adenocarcinoma, whereas no metastasis was observed. Cultured EJ cells produced tissue polypeptide antigen (IPA). Genetic and molecular analyses revealed high telomerase activity but not estrogen receptor alpha expression. Using the DNA sequencing technique, we have screened EJ cells for p53 mutation in exon 5 to 8 but no mutation of p53 was observed. This cell line appears to represent the development of a more malignant clone with divergent receptor function and growth behavior, and provides us with an interesting new tool for the study of tumorigenesis in the human endometrium.

Adenocarcinoma↗

PubMed2002

A quantitative analysis of geographic color variation in two Geotrupes dung beetles.

We conducted a quantitative analysis of geographic color variation in two species of dung beetles: Geotrupes auratus and G. laevistriatus. The reflectance of the dorsal surfaces was measured from 300 to 700 nm using a spectrophotometer. The reflectance curves for both beetles were bimodal; there were two distinct peaks, namely, the a peak, between 400 and 700 nm, and the beta peak at around 300 nm. A stepwise discriminant analysis indicated that geographic color variation in Geotrupes beetles was primarily characterized by a shift of the a peak. Using beetles from three locations, we compared the wavelength (nm) of the a peak (lambdamax(alpha)) and its reflectance intensity (R(a)) to investigate sex and population differences. Intraspecific geographic variation in coloration was effectively detected by discriminant analysis of spectral reflectance curves. Our results showed that G. auratus and G. laevistriatus had similar coloration within each sampling location. Our study also revealed hidden sex differences in R(a); R(a) of males were significantly higher than those of females in both species. Since the dorsal surface of the beetles shows remarkable color variation, and coloration can be assessed objectively using reflectance spectra, Geotrupes beetles may be good model organisms to investigate geographic color variation.

Animals↗

PubMedDate not supplied

Induction of apoptosis in human choriocarcinoma cell lines by treatment with 3,4-dihydro-6-[4-(3,4-dimethoxybenzoyl)-1-piperazinyl]-2(1H)-quinolinone (vesnarinone).

Induction of apoptosis is an attractive strategy in cancer therapy but it clinical practice is not yet sufficient in choriocarcinoma. The quinolinone derivative, vesnarinone, is a novel inotropic agent used for treating congestive heart failure and may also have a potential anticancer activity. It induces apoptosis and differentiation in some tumor cell lines. We examined the antitumor effect of vesnarinone in eight cell lines established from human choriocarcinoma and hydatidiform mole using MTT assay and also analyzed the nuclear fragmentation of tumor cells by DNA electrophoresis assay. Vesnarinone inhibited the proliferation of choriocarcinoma cell lines in a dose-dependent manner and induced DNA fragmentation in cells. However, the BM cell line prepared by subcultivation from hydatidiform mole showed no growth suppression or DNA fragmentation in response to vesnarinone. On the other hand, PCR-SSCP analysis and direct DNA sequencing have shown that a human choriocarcinoma cell line, SCH, has a mutant p53 gene at codon 249. When SCH cells were treated with vesnarinone cellular proliferation was significantly inhibited. Vesnarinone suppressed the proliferation of all choriocarcinoma cell lines and induced apoptosis, regardless of the existence of p53 mutation. In addition, it has been found by RT-PCR that expression of c-Myc mRNA is upregulated by treating choriocarcinoma cells with vesnarinone. The finding suggests that vesnarinone might induce expression of c-Myc gene in choriocarcinoma cells, the product of which may be associated with the inhibition of cell growth and induce apoptosis. These results suggest that vesnarinone is a useful reagent for the treatment of choriocarcinoma.

Antineoplastic Agents↗

PubMedDate not supplied

A novel phenoxazine derivative suppresses proliferation of human endometrial adenocarcinoma cell lines, inducing G2M accumulation and apoptosis.

We examined the effects of a novel phenoxazine, 2-amino-4,4alpha-dihydro-4alpha,7-dimethyl-3H-phenoxazine-3-one (Phx), which was produced by the reaction of 2-amino-5-methyl-phenol with bovine hemoglobin on the proliferation of human endometrial adenocarcinoma cell lines, EN and KLE cells, and on induction of apoptosis and G2M arrest in these cells. Phx inhibited proliferation of these cell lines in a dose- and time-dependent manner, i.e., the inhibition rate of proliferation of EN and KLE cells was 43% and 40%, respectively, in the presence of 50 micro M Phx, and 75% and nearly 100%, in the presence of 100 micro M Phx, after 2 days. When these endometrial adenocarcinoma cells were incubated with a medium containing 100 micro M Phx for 24 h, accumulation of EN and KLE cells in the S and G2M phase and that of apoptotic cells were demonstrated by flow cytometry. Apoptosis of these cells caused by Phx was unlikely to be associated with p53, Bax, and Bcl-2, because the levels of these proteins were not altered regardless of the presence or absence of Phx. The present results suggest that Phx demonstrates antitumor activity against human endometrial adenocarcinoma cell lines EN and KLE cells, by inducing both cell cycle accumulation at S and G2M and apoptosis associated with p53, Bcl-2 and Bax insensitive pathways.

Adenocarcinoma↗