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Featured researches published by Toshinari Muramatsu.


Journal of Obstetrics and Gynaecology Research | 2010

Granulosa cell tumor with activated mTOR-HIF-1α-VEGF pathway

Masaki Miyazawa; Masanori Yasuda; Mariko Fujita; Kenichi Hirabayashi; Takeshi Hirasawa; Hiroshi Kajiwara; Toshinari Muramatsu; Sayuri Miyazaki; Makiko Harasawa; Naruaki Matsui; Naoki Ogane; Masaru Murakami; Mikio Mikami; Toshihiko Yanase; R. Yoshiyuki Osamura

The DNA‐binding activity of hypoxia‐inducible factor‐1 α (HIF‐1α) has been analyzed for various gynecological tumors. Among the tumors that were studied, there was a finding of a high level of DNA‐binding HIF‐1α activity, although it was limited to one case of adult type granulosa cell tumor (GCT). In this case a 60‐year‐old female had marked immunohistochemical expression of HIF‐1α. The expressions of the mammalian target of rapamycin (mTOR) and phosphorylated‐mTOR (p‐mTOR) were also marked, and vascular endothelial growth factor (VEGF) was moderately expressed. To compare the expression profiles, 11 consecutive cases with adult type GCT were used. All cases showed marked expressions of HIF‐1α and mTOR, but p‐mTOR expression was moderately to markedly observed in four of the 12 cases. VEGF was expressed in all cases in varying degrees. Based on the evidence that downregulation of the mTOR pathway due to treatment with rapamycin (everolimus) would suppress tumor cell growth, an experimental study using the GCT cell line was designed to clarify whether HIF‐1α and VEGF expressions decline. As a result, the expressions of p‐mTOR, HIF‐1α and VEGF were suppressed, but those of mTOR were not. It was concluded that mTOR‐targeted therapy may represent a promising strategy for some GCT with an activated mTOR‐HIF‐1α‐VEGF pathway.


International Journal of Clinical Oncology | 2018

Japan Society of Gynecologic Oncology guidelines 2015 for the treatment of vulvar cancer and vaginal cancer

Toshiaki Saito; Tsutomu Tabata; Hitoshi Ikushima; Hiroyuki Yanai; Hironori Tashiro; Hitoshi Niikura; Takeo Minaguchi; Toshinari Muramatsu; Tsukasa Baba; Wataru Yamagami; Kazuya Ariyoshi; Kimio Ushijima; Mikio Mikami; Satoru Nagase; Masanori Kaneuchi; Nobuo Yaegashi; Yasuhiro Udagawa; Hidetaka Katabuchi

BackgroundVulvar cancer and vaginal cancer are relatively rare tumors, and there had been no established treatment principles or guidelines to treat these rare tumors in Japan. The first version of the Japan Society of Gynecologic Oncology (JSGO) guidelines for the treatment of vulvar cancer and vaginal cancer was published in 2015 in Japanese.ObjectiveThe JSGO committee decided to publish the English version of the JSGO guidelines worldwide, and hope it will be a useful guide to physicians in a similar situation as in Japan.MethodsThe guideline was created according to the basic principles in creating the guidelines of JSGO.ResultsThe guidelines consist of five chapters and five algorithms. Prior to the first chapter, basic items are described including staging classification and history, classification of histology, and definition of the methods of surgery, radiation, and chemotherapy to give the reader a better understanding of the contents of the guidelines for these rare tumors. The first chapter gives an overview of the guidelines, including the basic policy of the guidelines. The second chapter discusses vulvar cancer, the third chapter discusses vaginal cancer, and the fourth chapter discusses vulvar Paget’s disease and malignant melanoma. Each chapter includes clinical questions, recommendations, backgrounds, objectives, explanations, and references. The fifth chapter provides supplemental data for the drugs that are mentioned in the explanation of clinical questions.ConclusionOverall, the objective of these guidelines is to clearly delineate the standard of care for vulvar and vaginal cancer with the goal of ensuring a high standard of care for all women diagnosed with these rare diseases.


Journal of Obstetrics and Gynaecology Research | 2005

Case of uterine cervical carcinosarcoma

Tetsuji Iida; Masanori Yasuda; Hiroshi Kajiwara; Takeo Minematsu; R. Yoshiyuki Osamura; Johbu Itoh; Akifumi Inomo; Takeshi Hirasawa; Toshinari Muramatsu; Masaru Murakami

Carcinosarcoma (CS) is a rare neoplasm that is called a mixed epithelial and mesenchymal malignancy. CS of the uterine cervix is much less common than its counterparts in the uterine corpus. A 61‐year‐old, gravida 2, para 2 woman, who had undergone menopause 16 years prior to the presentation, was diagnosed with CS of the uterine cervix. A semiradical hysterectomy was carried out on the diagnosis of stage Ib1 cervical cancer. The patient underwent whole pelvic 45 Gy radiation as a postoperative additional treatment, but she died from multiple organ failure by metastasis 17 months after the operation. The tumor protruded from the cervix to the vagina and measured 4.5 × 3.0 cm. Histologically, the tumor was characterized as a squamous cell carcinoma and mesenchymal malignancy, represented by osteosarcomatous components. The stroma was largely composed of atypical spindle‐shaped cells, which were immunohistochemically demonstrated to be of epithelial origin. Uterine cervical CS is one of the aggressive malignancies, and squamous cell carcinomas are common epithelial counterparts of cervical CS as well as adenocarcinomas.


Genes to Cells | 2012

Glycan profiling of endometrial cancers using lectin microarray.

Yoshihiro Nishijima; Masashi Toyoda; Mayu Yamazaki-Inoue; Taro Sugiyama; Masaki Miyazawa; Toshinari Muramatsu; Kyoko Nakamura; Hisashi Narimatsu; Akihiro Umezawa; Mikio Mikami

Cell surface glycans change during the process of malignant transformation. To characterize and distinguish endometrial cancer and endometrium, we performed glycan profiling using an emerging modern technology, lectin microarray analysis. The three cell lines, two from endometrial cancers [well‐differentiated type (G1) and poorly differentiated type (G3)] and one from normal endometrium, were successfully categorized into three independent groups by 45 lectins. Furthermore, in cancer cells, a clear difference between G1 and G3 type was observed for the glycans recognized with six lectins, Ulex europaeus agglutinin I (UEA‐I), Sambucus sieboldiana agglutinin (SSA), Sambucus nigra agglutinin (SNA), Trichosanthes japonica agglutinin I (TJA‐I), Amaranthus caudatus agglutinin (ACA), and Bauhinia purpurea lectin (BPL). The lectin microarray analysis using G3 type tissues demonstrated that stage I and stage III or IV were distinguished depending on signal pattern of three lectins, Dolichos biflorus agglutinin (DBA), BPL, and ACA. In addition, the analysis of the glycans on the ovarian cancer cells showed that only anticancer drug‐sensitive cell lines had almost no activities to specific three lectins. Glycan profiling by the lectin microarray may be used to assess the characteristics of tumors and potentially to predict the success of chemotherapy treatment.


Modern Pathology | 2000

Immunohistochemical Study of Type-1 Blood Antigen Expressions in Thyroid Tumors: The Significance for Papillary Carcinomas

Shingo Kamoshida; Naoki Ogane; Masanori Yasuda; Toshinari Muramatsu; Takashi Bessho; Hiroshi Kajiwara; R. Yoshiyuki Osamura

Immunohistochemical expressions of type 1 blood group antigens were studied for 95 cases of thyroid tumors, including 29 follicular adenomas, 23 follicular carcinomas, and 43 papillary carcinomas, applying monoclonal antibodies against DU-PAN-2, CA19–9, Lewisa (Lea), and Lewisb (Leb). Normal thyroid tissue invariably failed to express all four antigens. In follicular adenomas, DU-PAN-2 and CA19–9 were focally expressed in 7% and 21% of cases, and in follicular carcinomas, CA19–9 expression was limited to one case (4%); all cases were negative for DU-PAN-2. No or little expression of Lea or Leb was observed in these follicular tumors. In contrast, DU-PAN-2, CA19–9, Lea, and Leb were expressed in 98%, 84%, 33%, and 49% of 43 papillary carcinomas, respectively. The positive stainings were observed mainly on the luminal surface of the tumor cells. The number of tumor cells that expressed DU-PAN-2 generally was greater than that of tumor cells that expressed CA19–9, Lea, or Leb. There was no significant difference in antigen expressions in female papillary carcinomas between subjects who were younger and older than 50 years old. The results suggest that DU-PAN-2 would be a useful immunohistochemical marker for distinguishing papillary carcinomas from follicular tumors. These immunohistochemical profiles imply the following: the activity of α2–3 sialyltransferase, a specific glycosyltransferase, would be more strongly enhanced in papillary carcinomas than in follicular tumors; the antigen expressions in papillary carcinomas may not be related to the alteration of the female sex hormone environment.


Acta Cytologica | 1997

Cytologic Study of Ascites and the Endometrium in Ovarian Carcinoma

Takeshi Hirasawa; Masanori Yasuda; Toshinari Muramatsu; Hitoshi Itoh; Takao Shinozuka; Tsunehisa Makino; Yutaka Tsutsumi; R. Yoshiyuki Osamura

OBJECTIVE To ascertain the usefulness of endometrial cytology with ovarian cancers when examining extension of the disease and to analyze significant factors associated with migration of ovarian cancer cells into the uterine cavity. STUDY DESIGN Cytologic results on ascites and the endometrium were analyzed in 87 patients with primary ovarian cancer in the absence of metastasis to the endometrium or cervicovagina. RESULTS Positive results for cytology were found in 62/87 of ascites cases (71.3%) and in 20/87 endometrium cases (23.0%). The 15 cases (15/62 or 24.2%) positive for ascitic and endometrial cytology, divided clinically into stage III (6 cases) and stage IV (9 cases), were classified histologically as serous, 7 cases; mucinous, 2 cases; clear cell, 4 cases; endometrioid, 1 case; and unclassified, 1 case. Half the clear cell carcinomas (4/8 or 50.0%) were positive in the ascites and endometrium. The ascitic volume at surgery exceeded 500 mL in 9/15 cases (60.0%). CONCLUSION Papillae with basement membrane material in the cores may be structurally associated with migration of ovarian cancer cells into the uterine cavity, especially in clear cell carcinomas. Cytologic positivity of the endometrium and ascites significantly correlated with ascitic volume.


Archives of Gynecology and Obstetrics | 2009

Immunohistochemical expression of somatostatin type 2A receptor in neuroendocrine carcinoma of uterine cervix

Hiroshi Kajiwara; Kenichi Hirabayashi; Masaki Miyazawa; Naoya Nakamura; Takeshi Hirasawa; Toshinari Muramatsu; Mikio Mikami; Masanori Yasuda; Robert Yoshiyuki Osamura

IntroductionSomatostatin and its analogues inhibit the growth of various kinds of endocrine and exocrine cells via the somatostatin receptor (SSTR). Expression of SSTR2A has been reported in many well-differentiated neuroendocrine tumors and small numbers of poorly differentiated neuroendocrine carcinomas. SSTR2A-positive neuroendocrine tumors may be treatable by SS analogues. Uterine cervical neuroendocrine carcinoma is generally associated with poor prognosis.Materials and methodsWe examined the expression of SSTR2A and other neuroendocrine markers [neural cell adhesion molecule (NCAM), chromogranin A, and synaptophysin] by immunohistochemical methods in seven neuroendocrine tumors of the uterine cervix: five small cell carcinomas and two large cell neuroendocrine carcinomas.ResultsSSTR2A was expressed in one small cell carcinoma and two neuroendocrine large cell carcinomas. The cell membrane of cells in these carcinomas showed strong immunohistochemical reactivity for SSTR2A. SSTR2A-positive cases are also frequently positive for the expression of chromogranin A. Treatment with SSTR2A may be effective for endocrine tumors. The results indicate the usefulness of SSTR2A analogs for the treatment of some uterine neuroendocrine carcinomas.


International Journal of Gynecological Cancer | 2013

Alterations of hypoxia-induced factor signaling pathway due to mammalian target of rapamycin (mTOR) suppression in ovarian clear cell adenocarcinoma: in vivo and in vitro explorations for clinical trial.

Takeshi Hirasawa; Masaki Miyazawa; Masanori Yasuda; Masako Shida; Masae Ikeda; Hiroshi Kajiwara; Naruaki Matsui; Mariko Fujita; Toshinari Muramatsu; Mikio Mikami

Objectives Before setting into the clinical trial using a combination of mammalian target of rapamycin (mTOR) inhibitors (rapamycin and everolimus) and other anticancer drugs, this study was conducted to confirm the efficacy of the new therapeutic strategy for ovarian clear cell adenocarcinoma (CCA), which targeted mTOR–hypoxia-induced factor (HIF) signal transduction system. Materials and Methods Using the cultured cells of CCA and animal models, alteration of mTOR-HIF cofactors and cell proliferation under the mTOR inhibitor–treated condition were analyzed. Results Mammalian target of rapamycin–HIF cofactors were inhibited dependent on concentration by mTOR inhibitor, resulting in suppression of the cultured CCA proliferation. However, von Hippel-Lindau was up-regulated at the messenger RNA level. In the nude mice with subcutaneously implanted CCA cells, apoptosis and necrosis were detected especially around the center of the tumors in the mTOR inhibitor–treated group more conspicuously than in the nontreated group. In the assessment of combination therapy with other antitumor agents, a combined treatment with mTOR inhibitor and chemotherapeutic agents caused a significant decrease in tumor size compared to the chemotherapeutic agents–only group. Conclusions Treatment by mTOR inhibitor is expected to down-regulate the cell proliferation of the CCA as a new therapeutic strategy.


Acta Histochemica Et Cytochemica | 2011

Analysis of mTOR Inhibition-Involved Pathway in Ovarian Clear Cell Adenocarcinoma

Makiko Harasawa; Masanori Yasuda; Takeshi Hirasawa; Masaki Miyazawa; Masako Shida; Toshinari Muramatsu; Kensho Douguchi; Naruaki Matsui; Susumu Takekoshi; Hiroshi Kajiwara; R. Yoshiyuki Osamura; Mikio Mikami

This study was designed to clarify the mechanism of the mammalian target of rapamycin (mTOR)-hypoxia inducible factor-1 (HIF-1) pathway using the cultured cell strain derived from human ovarian clear cell adenocarcinoma (CCA). Everolimus (a derivative of rapamycin)-treated cells and non-treated cells did not show any difference in mTOR expression. But, phosphorylated-mTOR (p-mTOR) expression significantly decreased in the treated cells, and mTOR-related factors such as phosphorylated-4E-BP1 (p-4E-BP1), HIF-1α, and vascular endothelial growth factor (VEGF) in the downstream region of mTOR revealed a marked decrease in expression. The analysis of influences of the drug on the HIF-1α degradation system showed an increase in von-Hippel Lindau (VHL) expression in the treated cells. Increase of cleaved caspase-3, one of key factors involved in apoptosis, was also shown in the treated cells. In the next step, using nude mice implanted with RMG-1 cells, a decrease in tumor size was demonstrated in 4 of the 7 mice which were orally administered with everolimus. As a result, it was suggested that everolimus administration would be helpful as an anti-tumor therapy for CCA not only via down-regulation of p-mTOR but also degradation of HIF-1α by VHL and induction of apoptosis by cleaved caspase-3.


Acta Histochemica Et Cytochemica | 2008

Alterations in Mucin Expression in Ovarian Mucinous Tumors: Immunohistochemical Analysis of MUC2, MUC5AC, MUC6, and CD10 Expression

Kenichi Hirabayashi; Masanori Yasuda; Hiroshi Kajiwara; Johbu Itoh; Masaki Miyazawa; Takeshi Hirasawa; Toshinari Muramatsu; Masaru Murakami; Mikio Mikami; Robert Yoshiyuki Osamura

The aim of this study was to evaluate the immunohistochemical expression of MUC2, MUC5AC, MUC6, and CD10 in ovarian mucinous adenoma (MA), mucinous borderline tumor (MB), and mucinous adenocarcinoma (MC), and to analyze the relationship between prognosis and these expressions. The expression of MUC2, MUC5AC, MUC6, and CD10 was evaluated by immunohistochemical analysis in 29 cases of MA, 29 cases of MB, and 26 cases of MC and scored based on the percentage of positive cells. Moreover, the ovarian mucinous tumors were classified into 4 phenotypes based on the staining patterns: intestinal, gastrointestinal, gastric, and unclassified patterns. The gastrointestinal pattern and the expression of MUC2 and CD10 increased from MA to MC. Conversely, the gastric pattern and MUC5AC expression decreased from MA to MC. Low MUC2 expression in MC was correlated with a better long-term survival rate. MUC2 expression in MC may be a useful predictor of the clinical outcome. The expression patterns of MUC2, MUC5AC, MUC6, and CD10 indicated that intestinal metaplasia may arise from the gastric-like epithelium in MA and that a close association exists between carcinogenesis and intestinal metaplasia in major ovarian mucinous tumors.

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