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Featured researches published by Ryuichiro Nishimura.


Gynecologic Oncology | 2009

Clinicopathological characteristics of mucinous adenocarcinoma of the ovary

Muneaki Shimada; Junzo Kigawa; Yoshihiro Ohishi; Makoto Yasuda; Mitsuaki Suzuki; Masamichi Hiura; Ryuichiro Nishimura; Tsutomu Tabata; Toru Sugiyama; Tsunehisa Kaku

OBJECTIVE We conducted the present study to clarify the clinicopathological characteristics of mucinous adenocarcinoma. METHODS Two hundred twenty-five patients were diagnosed with mucinous adenocarcinoma at individual institutes and underwent primary treatment between 1998 and 2003. Of these patients, 189 patients who could undergo central pathological review were enrolled in this study. Of 189 patients undergoing central pathological review, 64 patients (33.9%) were diagnosed with mucinous invasive adenocarcinoma, 45 mucinous intraepithelial carcinoma, and 42 mucinous tumor of borderline malignancy. Twenty-five patients were diagnosed with other histological subtypes, including 8 endometrioid adenocarcinoma, 5 clear cell carcinoma, 3 serous adenocarcinoma, and 4 mixed type. There were 13 cases of metastatic mucinous adenocarcinoma, including 7 pseudomyxoma peritonei. Four hundred thirty-three patients with serous adenocarcinoma were used as controls. RESULTS Forty-five patients with mucinous invasive carcinoma were in FIGO I-II stages and 19 in III-IV stages. There was no difference in the outcome between mucinous invasive adenocarcinoma and serous adenocarcinoma in I-II stage patients and III-IV stage patients with optimal operation. In contrast, patients with mucinous invasive adenocarcinoma receiving suboptimal operation showed a significantly worse prognosis (survival rate: 27.8% vs. 61.5%). The response rate to chemotherapy for mucinous invasive adenocarcinoma was significantly lower than for serous adenocarcinoma (12.5% vs. 67.7%). CONCLUSIONS The diagnosis of mucinous invasive adenocarcinoma was difficult. Since patients with mucinous invasive adenocarcinoma had a lower response to chemotherapy, aggressive cytoreductive surgery was an effective treatment to improve the prognosis for advanced stage patients. A new chemotherapeutic regimen should be established for mucinous adenocarcinoma of the ovary.


American Journal of Pathology | 2010

Absence of High-Risk Human Papillomavirus (HPV) Detection in Endocervical Adenocarcinoma with Gastric Morphology and Phenotype

Yasuki Kusanagi; Atsumi Kojima; Yoshiki Mikami; Takako Kiyokawa; Tamotsu Sudo; Satoshi Yamaguchi; Ryuichiro Nishimura

A subset of endocervical-type mucinous adenocarcinomas (ACs) of the uterine cervix exhibit a gastric phenotype and morphology, as reported in cases of minimal deviation AC in which the presence of human papillomavirus (HPV) has been rarely detected. To investigate the HPV-independent pathway of carcinogenesis in cases of gastric-type AC, we investigated the common high-risk HPV (hr-HPV) status in 52 nonsquamous cell carcinomas, using a PCR-based typing method and immunohistochemistry of p16INK4a (a cyclin-dependent kinase inhibitor that is overexpressed in both cancerous and precancerous cervical tissue, making it an ideal biomarker for cervical cancer cases). Using novel morphological criteria, seven of 52 (13.5%) carcinomas were designated as gastric-type ACs, all of which were negative for both hr-HPV DNA and p16INK4a. Nongastric-type ACs were frequently positive for both hr-HPV DNA (90%, 28/31) and p16INK4a (94%, 29/31) with adenosquamous and neuroendocrine carcinomas demonstrating the presence of hr-HPV DNA in 86% (6/7) and 83% (5/6) of cases, respectively. In these two types of carcinoma, 86% (6/7) and 100% (6/6) were positive for p16INK4a, respectively. Our data suggests that gastric-type AC appears to represent an oncogenic hr-HPV-independent neoplasm and therefore is a potential pitfall of HPV DNA testing and vaccination.


Biology of Reproduction | 2000

Human Villous Macrophage-Conditioned Media Enhance Human Trophoblast Growth and Differentiation In Vitro

Salma Khan; Hidetaka Katabuchi; Masako Araki; Ryuichiro Nishimura; Hitoshi Okamura

Abstract In human chorionic villi, numerous macrophages, so-called Hofbauer cells, are located adjacent to trophoblasts. To determine the role of the macrophages in the proliferation and differentiation of trophoblasts, cytotrophoblast cells were cultured in serum-free culture-conditioned media of villous macrophages (VMCM), peritoneal macrophages (PMCM), and villous fibroblasts (VFCM). In VMCM, proliferation of cytotrophoblast cells was detected at 24 h by immunocytochemistry with Ki-67-antibody. A large number (P < 0.001) of multinucleated syncytia was formed in VMCM. In VMCM, cytotrophoblast cell fusion was completed by 96 h, which coincided with the peak of hCG secretion and initiation of human placental lactogen (hPL) release. Levels of hCG (P < 0.001) and hPL (P < 0.001) secretion from syncytial cells were significantly higher in VMCM than in PMCM or in VFCM. Concentrations of macrophage colony-stimulating factor (M-CSF) and vascular endothelial growth factor (VEGF) analyzed by ELISA were greater in VMCM than in PMCM or in VFCM, whereas monocyte chemoattractant protein-1 (MCP-1) concentration was high in PMCM. The expression patterns of M-CSF, VEGF, and MCP-1 in villous macrophages and peritoneal macrophages by reverse transcriptase-polymerase chain reaction were similar to their secretion patterns. Thus, villous macrophages have a greater ability to stimulate hCG and hPL secretion than do peritoneal macrophages. This study suggests that macrophages within the villous stroma may stimulate the growth and differentiation of trophoblasts through their secreted substances.


Scientific Reports | 2011

Potential role of LMP2 as tumor-suppressor defines new targets for uterine leiomyosarcoma therapy

Takuma Hayashi; Akiko Horiuchi; Kenji Sano; Nobuyoshi Hiraoka; Mari Kasai; Tomoyuki Ichimura; Tamotsu Sudo; Yoh-ichi Tagawa; Ryuichiro Nishimura; Osamu Ishiko; Yae Kanai; Nobuo Yaegashi; Hiroyuki Aburatani; Tanri Shiozawa; Ikuo Konishi

Although the majority of smooth muscle neoplasms found in the uterus are benign, uterine leiomyosarcoma (LMS) is extremely malignant, with high rates of recurrence and metastasis. We earlier reported that mice with a homozygous deficiency for LMP2, an interferon (IFN)-γ-inducible factor, spontaneously develop uterine LMS. The IFN-γ pathway is important for control of tumor growth and invasion and has been implicated in several cancers. In this study, experiments with human and mouse uterine tissues revealed a defective LMP2 expression in human uterine LMS that was traced to the IFN-γ pathway and the specific effect of JAK-1 somatic mutations on the LMP2 transcriptional activation. Furthermore, analysis of a human uterine LMS cell line clarified the biological significance of LMP2 in malignant myometrium transformation and cell cycle, thus implicating LMP2 as an anti-tumorigenic candidate. This role of LMP2 as a tumor suppressor may lead to new therapeutic targets in human uterine LMS.


Gynecologic Oncology | 2013

Histopathology predicts clinical outcome in advanced epithelial ovarian cancer patients treated with neoadjuvant chemotherapy and debulking surgery

Miho Muraji; Tamotsu Sudo; Shinichi Iwasaki; Sayaka Ueno; Senn Wakahashi; Satoshi Yamaguchi; Kiyoshi Fujiwara; Ryuichiro Nishimura

OBJECTIVE To analyze the factors prognostic of survival in patients with advanced epithelial ovarian cancer (EOC) treated with neoadjuvant chemotherapy (NAC) followed by interval debulking surgery. METHODS Outcomes were retrospectively in patients with advanced EOC or peritoneal cancer who received neoadjuvant paclitaxel and carboplatin chemotherapy every 3 weeks for three to four cycles, followed by interval debulking surgery and three additional cycles of the same regimens from January 2001 to November 2010. Therapeutic response was assessed histopathologically as grade 0 to 3, based on the degree of disappearance of cancer cells, displacement by necrotic and fibrotic tissue, and tumor-induced inflammation. Factors prognostic of progression-free survival (PFS) and overall survival (OS) were calculated. RESULTS The 124 enrolled patients had a median age of 62 years (range, 35-79 years). Viable cancer cells were observed in specimens resected from 72 patients (58%) at interval debulking surgery after NAC. Multivariate analysis using the Cox proportional hazard model showed that advanced (stage IV) disease (hazard ratio [HR]=1.94, p=0.003), residual cancer at the end of surgery ≥1cm (HR=3.78, p<0.001), and histological grade 0-1 (HR=1.65, p=0.03) were independent predictors of decreased OS. Grade 0-1 was also an independent predictor of increased risk of relapse within 6 months (odds ratio=8.42, p=0.003). CONCLUSIONS Residual disease of ≥1cm, advanced stage, and the presence of more viable disease in resected specimens are prognostic factors for survival in advanced EOC patients receiving NAC followed by interval debulking surgery.


FEBS Letters | 2012

Potential role of LMP2 as an anti-oncogenic factor in human uterine leiomyosarcoma: Morphological significance of calponin h1

Takuma Hayashi; Akiko Horiuchi; Kenji Sano; Nobuyoshi Hiraoka; Mari Kasai; Tomoyuki Ichimura; Tamotsu Sudo; Ryuichiro Nishimura; Osamu Ishiko; Tanri Shiozawa; Yae Kanai; Nobuo Yaegashi; Hiroyuki Aburatani; Ikuo Konishi

Uterine leiomyosarcoma (LMS) is a highly metastatic smooth muscle neoplasm for which calponin h1 is suspected to have a biological role as a tumor‐suppressor. We earlier reported that LMP2‐null mice spontaneously develop uterine LMS through malignant transformation of the myometrium, thus implicating this protein as an anti‐tumorigenic candidate as well. In the present study, we show that LMP2 may negatively regulate LMS independently of its role in the proteasome. Moreover, several lines of evidence indicate that although calponin h1 does not directly influence tumorigenesis, it clearly affects LMP2‐induced cellular morphological changes. Modulation of LMP2 may lead to new therapeutic approaches in human uterine LMS.


Oncology Reports | 2012

Phase II study of neoadjuvant chemotherapy with irinotecan hydrochloride and nedaplatin followed by radical hysterectomy for bulky stage Ib2 to IIb, cervical squamous cell carcinoma: Japanese Gynecologic Oncology Group study (JGOG 1065).

Satoshi Yamaguchi; Ryuichiro Nishimura; Nobuo Yaegashi; Kazushige Kiguchi; Toru Sugiyama; Tsunekazu Kita; Kaneyuki Kubushiro; Katsuji Kokawa; Masamichi Hiura; Katsumi Mizutani; Kaichiro Yamamoto; Ken Takizawa

The efficacy and adverse events of neoadjuvant chemotherapy with irinotecan hydrochloride and nedaplatin were evaluated in patients with bulky stage Ib2 to IIb cervical squamous cell carcinoma. Eligibility included patients who received irinotecan (60 mg/m2) on days 1 and 8 and nedaplatin (80 mg/m2) on day 1 of a 21-day cycle. After 1-3 courses of chemotherapy, radical hysterectomy was performed. Sixty-eight patients were enrolled. Sixty-six were included in the full analysis set. Their median age was 47 years (range 22-71), the FIGO stage was Ib2 in 18 patients, IIa in 10, and IIb in 38. Radical hysterectomy was performed after NAC in 63 patients (95.5%). The number of administered courses of NAC was 1 in 13 patients, 2 in 43, and 3 in 10. The response rate, the primary endpoint of this study, was 75.8% (CR in 2 patients, PR in 48, SD in 12, PD in 0, and NE in 4). The mean number of treatment courses required for a response was 1.42 (1 course in 30 patients, 2 courses in 19, and 3 courses in 1). The incidences of grade 3 or 4 hematological toxicities were: neutropenia 72.2%, leukopenia 16.7%, anemia 13.6%, thrombocytopenia 7.6%, febrile neutropenia 1.5%, and elevations of alanine aminotransferase and aspartate aminotransferase 1.5%. Grade 3 or 4 non-hematologic toxicities were as follows: diarrhea 6.1%, nausea 3%, anorexia 1.5%, vomiting 1.5%, fever 1.5%, allergic reactions 1.5%, ileus 1.5% and vesicovaginal fistula 1.5%. Neoadjuvant chemotherapy with irinotecan and nedaplatin was an effective and well-tolerated treatment for patients with bulky stage Ib2 to IIb squamous cell carcinoma of the uterine cervix.


Gynecologic Oncology | 2008

Germ cell specific protein VASA is over-expressed in epithelial ovarian cancer and disrupts DNA damage-induced G2 checkpoint

Hisashi Hashimoto; Tamotsu Sudo; Yoshiki Mikami; Mieko Otani; Masaoki Takano; Hiroshi Tsuda; Hiroaki Itamochi; Hidetaka Katabuchi; Masaharu Ito; Ryuichiro Nishimura

OBJECTIVE Cancer cells have characteristics, such as high telomerase activity and high levels of migration activity and proliferation, which are very similar to those of germ cell lineages. In this study, we examined the expression of VASA, a germ cell lineage specific marker and evaluated its clinical significance in epithelial ovarian cancer (EOC). METHODS We investigated VASA expression in 75 EOC tissues by immunohistochemistry, correlating results with clinicopathological factors. To clarify the effects of VASA on cellular phenotypes, we compared the protein expression profiles between SKOV-3 cells stably expressing VASA (SKOV-3-VASA) and vector-control cell lines by coupling 2D fingerprinting and identification of proteins by mass spectrometry. RESULTS VASA expression in tumor cells was found in 21 of 75 cases and was positively correlated with high age and serous histology. Significant down-regulation of 14-3-3sigma was observed in SKOV-3-VASA versus control cells. Over-expression of VASA abrogates the G2 checkpoint, induced by DNA damage, by down-regulating the expression of 14-3-3sigma. CONCLUSIONS These results suggest that VASA may either play a direct role in the progression of EOC or serve as a valuable marker of tumorigenesis.


International Journal of Gynecological Cancer | 2012

Type II versus type III fertility-sparing abdominal radical trachelectomy for early-stage cervical cancer: a comparison of feasibility of surgical outcomes.

Miho Muraji; Tamotsu Sudo; Eriko Nakagawa; Sayaka Ueno; Senn Wakahashi; Seiji Kanayama; Takashi Yamada; Satoshi Yamaguchi; Kiyoshi Fujiwara; Ryuichiro Nishimura

Objective The purpose of this study was to compare surgical outcomes using modified (type II) and traditional (type III) abdominal radical trachelectomy (ART) for fertility-sparing surgery in early cervical cancer. Methods A prospectively maintained database of ART procedures was analyzed. Data were collected regarding age, stage, histology, operative outcome, surgical complication, and fertility outcome. Results We performed 23 fertility-sparing ARTs for patients with International Federation of Gynecology and Obstetrics stages IA to IB1 tumors of less than 2 cm between 2006 and 2010. Type III ART was attempted in 8 patients and modified ART in 15 patients. The median operating time was greater in the type III group compared with that in the type II group (305 vs 247 minutes; P < 0.02). The median surgical blood loss was greater in the type III ART group (580 mL; range, 250–988 mL) compared with that in the modified type II group (366 mL; range, 200–850 mL; P < 0.05). The median time to recovery of bladder dysfunction was less in the type II group (9 days; range, 3–10 days) than that in the type III group (13 days; range, 10–23 days; P < 0.01). There were no recurrences at the time of this report. Conclusions Type II ART provides surgical and pathological outcomes with better recovery of bladder function similar to those in type III ART. For patients with early cervical cancer who wish to preserve reproductive function, type II ART is a feasible and safe operation.


International Journal of Gynecological Cancer | 2013

L1 gene methylation in high-risk human papillomaviruses for the prognosis of cervical intraepithelial neoplasia.

Noriko Oka; Masahiro Kajita; Ryuichiro Nishimura; Chiho Ohbayashi; Tamotsu Sudo

Objective The purpose of this study was to investigate the clinical significance of DNA methylation of the human papillomavirus (HPV) genome as a prognostic biomarker for cervical intraepithelial neoplasia (CIN). Methods and Materials Clinical samples (paraffin-embedded tissues obtained by conization/hysterectomy or initial punch biopsy) were collected from patients at the Gynecologic Oncology of the Hyogo Cancer Center with informed consent. We evaluated the methylation status of the L1 gene of the HPV genome by bisulfite sequencing, calculating the methylation ratio (L1MR) as (number of methylated CpGs in the analyzed region of the L1 gene) / (number of all CpGs in the analyzed region of the L1 gene) × 100. The methylation analysis and in situ hybridization were performed with serial tissue-section slices. Results DNA methylation was observed in the L1 gene, but not in the long control region of HPV-16, -18, or the other high-risk HPV types including HPV-31, -52, and -58. L1MR was associated with the CIN grade; the median L1MR was 2.3%, 11.2%, 35.2%, and 50.0% for CIN1, CIN2, CIN3, and squamous cell carcinoma, respectively. L1MRs also seemed to indicate physical status (integrated or episomal form) of the HPV genome in the host cell. L1MR of the progression group was significantly higher than that of the regression group. Conclusions L1MR was associated with the CIN grade and indicated the HPV genome status in the host cell: high L1MR indicated HPV genome integration linked to progression from early-stage CINs, whereas low L1MR indicated an episomal HPV genome location in host cells. L1MR may be a prognostic indicator of CIN.

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Tamotsu Sudo

University of Texas MD Anderson Cancer Center

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Toru Sugiyama

Iwate Medical University

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