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Dive into the research topics where Hitoshi Takayama is active.

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Featured researches published by Hitoshi Takayama.


Autonomous Robots | 2010

Pneumatic-driven jumping robot with anthropomorphic muscular skeleton structure

Koh Hosoda; Yuki Sakaguchi; Hitoshi Takayama; Takashi Takuma

Human muscular skeleton structure plays an important role for adaptive locomotion. Understanding of its mechanism is expected to be used for realizing adaptive locomotion of a humanoid robot as well. In this paper, a jumping robot driven by pneumatic artificial muscles is designed to duplicate human leg structure and function. It has three joints and nine muscles, three of them are biarticular muscles. For controlling such a redundant robot, we take biomechanical findings into account: biarticular muscles mainly contribute to joint coordination whereas monoarticular muscles contribute to provide power. Through experiments, we find (1) the biarticular muscles realize coordinated movement of joints when knee and/or hip is extended, (2) the extension of the ankle does not lead to coordinated movement, and (3) we can superpose extension of the knee with that of the hip without losing the joint coordination. The obtained knowledge can be used not only for robots, but may also contribute to understanding of adaptive human mechanism.


BJUI | 2011

Infiltration of tumour‐associated macrophages in prostate biopsy specimens is predictive of disease progression after hormonal therapy for prostate cancer

Norio Nonomura; Hitoshi Takayama; Masashi Nakayama; Yasutomo Nakai; Atsunari Kawashima; Masatoshi Mukai; Akira Nagahara; Katsuyuki Aozasa; Akira Tsujimura

Study Type – Prognostic (case series)


International Journal of Cancer | 2007

Sesquiterpene lactone parthenolide suppresses tumor growth in a xenograft model of renal cell carcinoma by inhibiting the activation of NF-κB

Daizo Oka; Kazuo Nishimura; Masahiro Shiba; Yasutomo Nakai; Yasuyuki Arai; Masashi Nakayama; Hitoshi Takayama; Hitoshi Inoue; Akihiko Okuyama; Norio Nonomura

The transcription factor nuclear factor‐κB (NF‐κB) has been shown to be constitutively activated in various human malignancies, including leukemia, lymphoma and a number of solid tumors. NF‐κB regulates the transcriptional of genes important for tumor invasion, metastasis and chemoresistance. The sesquiterpene lactone parthenolide, an inhibition of NF‐κB, has been used conventionally to treat migraines and inflammation. In this study, renal cancer cell lines OUR‐10 and ACHN were used for in vitro experiments to evaluate growth‐inhibitory effects of parthenolide. An OUR‐10 xenograft model in nude mice was also used to investigate the in vivo growth‐inhibitory effects of parthenolide. Apoptosis in response to treatment of OUR‐10 cells with parthenolide was confirmed. Localization of NF‐κB in response to parthenolide treatment was examined of by immunofluorostaining of OUR‐10 cells with antibody against NF‐κB p65 and by Western blot analysis of OUR‐10 cell and tumor nuclear and cytosol fraction. Parthenolide effectively inhibited proliferation of cultured OUR‐10 cells and triggered apoptosis in vitro. Subcutaneous injection or oral administration of parthenolide showed significant tumor growth inhibition in the xenograft model via decreased production of interleukin‐8 (IL‐8) or vascular endothelial growth factor (VEGF). Immunohistochemistry and Western blot analysis showed decreased nuclear localization of NF‐κB and phosphorylated NF‐κB protein and subsequently expression of MMP‐9, Bcl‐xL and Cox‐2 in response to parthenolide treatment. These results indicate that parthenolide is a useful in the treatment of renal cell carcinoma and acts via inhibition of NF‐κB.


The Journal of Urology | 2009

Increased Infiltration of Tumor Associated Macrophages is Associated With Poor Prognosis of Bladder Carcinoma In Situ After Intravesical Bacillus Calmette-Guerin Instillation

Hitoshi Takayama; Kazuo Nishimura; Akira Tsujimura; Yasutomo Nakai; Masashi Nakayama; Katsuyuki Aozasa; Akihiko Okuyama; Norio Nonomura

PURPOSE Tumor associated macrophages can regulate the growth of various cancers positively or negatively. Intravesical bacillus Calmette-Guerin instillation is now gold standard treatment for bladder carcinoma in situ. We investigated the correlation between tumor associated macrophages infiltrating bladder carcinoma in situ and the response to intravesical bacillus Calmette-Guerin therapy. MATERIALS AND METHODS We examined paraffin embedded tissues from 41 patients with bladder carcinoma in situ who received intravesical bacillus Calmette-Guerin therapy. Tumor associated macrophages were immunohistochemically stained by anti-CD68 monoclonal antibody. RESULTS The median number of tumor associated macrophages infiltrating among cancer cells and the number in the lamina propria were 4 and 24, respectively. Recurrent carcinoma in situ was found in 4.8% of cases with a lower cancer cell tumor associated macrophage count but in 47.6% of those with a higher cancer cell tumor associated macrophage count (less than 4 vs 4 or greater). Recurrence was found in 31.8% of patients with a lower lamina propria tumor associated macrophage count but in 21.1% of those with a higher lamina propria tumor associated macrophage count (less than 25 vs 25 or greater). The median ratio of tumor associated macrophages among cancer cells vs in the lamina propria was 0.2. Recurrence-free survival was significantly better in patients with a lower cancer cell tumor associated macrophage count (p = 0.0002). Those with a lower cancer cell-to-lamina propria tumor associated macrophage ratio had a higher recurrence-free rate (p <0.0001). Multivariate analysis revealed that the cancer cell tumor associated macrophage count and the cancer cell-to-lamina propria tumor associated macrophage ratio can be prognostic factors for bladder carcinoma in situ. CONCLUSIONS The count of tumor associated macrophages infiltrating the cancer area is useful for predicting the response of bladder carcinoma in situ to intravesical bacillus Calmette-Guerin instillation before treatment initiation.


Clinical Cancer Research | 2011

Excision Repair Cross-Complementing Group 1 May Predict the Efficacy of Chemoradiation Therapy for Muscle-Invasive Bladder Cancer

Atsunari Kawashima; Masashi Nakayama; Yoichi Kakuta; Toyofumi Abe; Koji Hatano; Masatoshi Mukai; Akira Nagahara; Yasutomo Nakai; Daizo Oka; Hitoshi Takayama; Toshiaki Yoshioka; Yoshihiko Hoshida; Hiroaki Itatani; Kazuo Nishimura; Norio Nonomura

Purpose: Chemoradiation therapy (CRT) is now widely recognized as bladder-preserving therapy for muscle-invasive bladder cancer (MIBC). However, some patients who fail CRT may miss the chance to be cured by cystectomy. Therefore, it is important to select patients with MIBC who are expected to have a good response to CRT. Several reports indicate that the excision repair cross-complementing group 1 (ERCC1) gene is associated with resistance to cisplatin and radiation therapy. In this study, we examined the correlation between ERCC1 and CRT in vitro and in vivo in bladder cancer. Experimental Design: Bladder cancer cell lines T24, 5637, Cl8-2 (multidrug-resistant subline of T24), and CDDP10-3 (cisplatin-resistant subline of T24) were used for in vitro assays to measure ERCC1 expression level and growth inhibition with cisplatin or ionizing radiation (IR). We then examined by immunohistochemistry that whether ERCC1 nuclear staining correlates with the efficacy of CRT using cisplatin in 22 patients with MIBC. Results: Cl8-2 cells expressed ERCC1 mRNA 5.96-fold higher than did T24. Cl8-2 and CDDP10-3 were more resistant to cisplatin or IR than was T24. Resistance to IR, but not to cisplatin, was removed by suppressing ERCC1 using siRNA in both Cl8-2 and CDDP10-3 cells. In immunohistochemistry with ERCC1, 6 of 8 positive cases did not have complete response to CRT, whereas 12 of 14 negative cases had complete response. Sensitivity and specificity were 75% and 85.7%, respectively (P = 0.008). Conclusion: Although further study is needed, ERCC1 expression level may predict the efficacy of CRT for MIBC. Clin Cancer Res; 17(8); 2561–9. ©2010 AACR.


Laboratory Investigation | 2001

Fas Gene Mutations in Prostatic Intraepithelial Neoplasia and Concurrent Carcinoma: Analysis of Laser Capture Microdissected Specimens

Hitoshi Takayama; Tetsuya Takakuwa; Zhiming Dong; Norio Nonomura; Akihiko Okuyama; Shigekazu Nagata; Katsuyuki Aozasa

Fas (Apo-1/CD95) is a cell-surface receptor involved in cell death signaling through binding of Fas ligand. Mutations of the Fas gene might be involved in proliferative diseases of the prostate by prolongation of programmed cell death of prostatic epithelial cells. Using the laser capture microdissection method, Fas gene mutations were examined on genomic DNA extracted from lesions with high-grade prostatic intraepithelial neoplasia (HGPIN), a possible precursor of prostatic cancer (PCA), and from PCA. A total of 193 lesions, 111 with HGPIN, 55 with PCA, and 27 benign glands, were microdissected from 27 patients with PCA. Polymerase chain reaction-amplified products were directly sequenced. Loss of heterozygosity (LOH) was examined at four sites of known polymorphisms. Fas gene mutations were detected in HGPIN: 4 of 27 (14.8%) cases or 4 of 111 (3.6%) lesions. All were point mutations: three missense and one nonsense in the death domain. Benign proliferative glands adjoining HGPIN and/or PCA, and PCA never showed mutations. LOH was found in 31.3% of PCA and 25% of HGPIN lesions, but was never found in benign glands. Exclusive occurrence of Fas mutations in HGPIN might underlie the development of these lesions. Occasional findings of LOH in HGPIN and PCA suggested that genetic instability might occur during the early phase of prostatic carcinogenesis.


PLOS ONE | 2013

EMMPRIN Promotes Angiogenesis, Proliferation, Invasion and Resistance to Sunitinib in Renal Cell Carcinoma, and Its Level Predicts Patient Outcome

Mototaka Sato; Yasutomo Nakai; Wataru Nakata; Takahiro Yoshida; Koji Hatano; Atsunari Kawashima; Kazutoshi Fujita; Motohide Uemura; Hitoshi Takayama; Norio Nonomura

Purpose Extracellular matrix metalloproteinase inducer (EMMPRIN) has been reported to play crucial roles, including in angiogenesis, in several carcinomas. However, the correlation between EMMPRIN levels and angiogenesis expression profile has not been reported, and the role of EMMPRIN in renal cell carcinoma (RCC) is unclear. In the present study, we evaluated the association of EMMPRIN with angiogenesis, its value in prognosis, and its roles in RCC. Experimental Design EMMPRIN expression was examined in 50 RCC patients treated with radical nephrectomy. Angiogenesis, proliferation, and invasion activity were evaluated using EMMPRIN knockdown RCC cell lines. The size of EMMPRIN-overexpressing xenografts was measured and the degree of angiogenesis was quantified. EMMPRIN expression was evaluated in RCC patients who received sunitinib therapy and in sunitinib-resistant cells. Further, the relation between EMMPRIN expression and sensitivity to sunitinib was examined. Results EMMPRIN score was significantly associated with clinicopathological parameters in RCC patients, as well as being significantly correlated with microvessel area (MVA) in immature vessels and with prognosis. Down-regulation of EMMPRIN by siRNA led to decreased VEGF and bFGF expression, cell proliferation, and invasive potential. EMMPRIN over-expressing xenografts showed accelerated growth and MVA of immature vessels. EMMPRIN expression was significantly increased in patients who received sunitinib therapy as well as in sunitinib-resistant 786-O cells (786-suni). EMMPRIN-overexpressing RCC cells were resistant to sunitinib. Conclusion Our findings indicate that high expression of EMMPRIN in RCC plays important roles in tumor progression and sunitinib resistance. Therefore, EMMPRIN could be a novel target for the treatment of RCC.


Japanese Journal of Clinical Oncology | 2011

Clinical Outcome and Prognostic Factors of Sorafenib in Japanese Patients with Advanced Renal Cell Carcinoma in General Clinical Practice

Go Tanigawa; Atsunari Kawashima; Seiji Yamaguchi; Kazuo Nishimura; Miyoshi S; Jiro Kajikawa; Norio Meguro; Toshiaki Yosioka; Toshitsugu Oka; Tsuneo Hara; Hitoshi Takayama; Norio Nonomura

OBJECTIVE Effects of sorafenib in general clinical practice, especially those with patients of Asian ethnicity, have been rarely investigated. We assessed efficacy, safety and prognostic factors for progression-free survival in Japanese patients receiving sorafenib for advanced renal cell carcinoma. METHODS We performed a retrospective analysis of 159 Japanese patients with renal cell carcinoma. Progression-free survival was estimated by the Kaplan-Meier method. Objective response (per Response Evaluation Criteria in Solid Tumors) and safety were assessed. Cox proportional hazards model was used to identify independent prognostic factors for progression-free survival. RESULTS The median progression-free survival was 9.0 months (95% confidence interval, 7.5-10.6 months). In 142 patients with measurable lesions, the objective response rate was 21.8%, and disease control was achieved in 85 (59.9%) patients. Adverse events of any grade occurred in 152 patients (95.6%). Most common adverse events causing discontinuation or interruption of sorafenib were hand-foot skin reaction (22%), rash (10.7%) and liver dysfunction (10.7%). Dose reduction or therapy interruption due to adverse events was required in 128 patients (80.5%). Univariate and multivariate analysis revealed that favorable prognosis according to Memorial Sloan-Kettering Cancer Center prognostic factors and relative dose intensity during the first month of treatment of ≥50% were significant factors for predicting superior progression-free survival with sorafenib treatment. CONCLUSIONS Sorafenib was effective in Japanese patients with advanced renal cell carcinoma in general clinical practice and was tolerated although most patients required dose reduction or interruption of therapy. Future studies should establish new strategies for treatment without sacrificing both efficacy and patient quality of life.


Biochemical and Biophysical Research Communications | 2010

SERPINE2 is a possible candidate promotor for lymph node metastasis in testicular cancer

Akira Nagahara; Masashi Nakayama; Daizo Oka; Mutsumi Tsuchiya; Atsunari Kawashima; Masatoshi Mukai; Yasutomo Nakai; Hitoshi Takayama; Kazuo Nishimura; Yoshimasa Jo; Atsushi Nagai; Akihiko Okuyama; Norio Nonomura

Testicular germ cell tumors (TGCTs) commonly metastasize to the lymph node or lung. However, it remains unclear which genes are associated with TGCT metastasis. The aim of this study was to identify gene(s) that promoted human TGCT metastasis. We intraperitoneally administered conditioned medium (CM) from JKT-1, a cell-line from a human testicular seminoma, or JKT-HM, a JKT-1 cell sub-line with high metastatic potential, into mice with JKT-1 xenografts. Administration of CM from JKT-HM significantly promoted lymph node metastasis. A cDNA microarray analysis showed that JKT-HM cells highly expressed the Serpine peptidase inhibitor, clade E, member 2 (SERPINE2), which encodes a secreted protein. Administration of CM from SERPINE2-silenced JKT-HM cells inhibited lymph node metastasis in the xenograft model, compared with administration of CM from JKT-HM cells. There was no significant difference in xenograft volume. Moreover, administration of CM from SERPINE2-over-expressing JKT-1 was likely to promote lymph node metastasis in the xenograft model. There was no difference in the in vitro proliferation or migration of JKT-1 cells cultured with CM from JKT-HM cells, compared to that with CM from JKT-1. There was no promotion of proliferation or lymphangiogenesis in the xenografts, as measured by Ki-67 and LYVE-1 immunohistochemistry, respectively. Although we could not clarify how SERPINE2 promoted lymph node metastasis, it may be a promoter in the development of lymph node metastasis in the human seminoma cells in a mouse xenograft model.


American Journal of Pathology | 2002

Frequent Fas gene mutations in testicular germ cell tumors.

Hitoshi Takayama; Tetsuya Takakuwa; Yuichi Tsujimoto; Yoichi Tani; Norio Nonomura; Akihiko Okuyama; Shigekazu Nagata; Katsuyuki Aozasa

The Fas (Apo-1/CD95)/Fas ligand (L) system is involved in cell death signaling, and has been suggested to be important for the regulation of germ cell apoptosis in the testis. Mutations of the Fas gene may result in accumulation of germ cells and thus might contribute to testicular carcinogenesis. The open reading frame of Fas cDNA was examined in 24 cases of testicular germ cell tumors (TGCTs), comprised of 19 pure histological type (15 seminomas, 3 embryonal carcinomas, 1 immature teratoma) and 5 mixed-type tumors. Mutations of the Fas gene were found in nine (37.5%) of these cases. Each lesion with a homogeneous histological picture was selectively microdissected using a laser capture microdissection method: samples consisted of 18 lesions from seminomas, 7 embryonal carcinomas, 4 immature teratomas, 2 choriocarcinomas, and 1 from a yolk sac tumor. Microdissected genomic DNA was examined to determine which mutations were derived from which kind of histological lesion. Eleven mutations were detected in 10 TGCT lesions from nine cases, but none were found in benign lesions. All were point mutations, and eight missense mutations occurred in exon 9 encoding the core protein of the death domain essential for apoptotic signal transduction. Three were silent mutations. Mutations were found in the seminoma (27.8%) and embryonal carcinoma lesions (62.5%), but none were found in the one yolk sac tumor, two choriocarcinomas, or four immature teratoma lesions. Each seminoma and embryonal carcinoma lesion found in the same case had a different type of Fas mutation from the others. Mouse T-cell lymphoma cells transfected with missense mutated genes were resistant to apoptosis induced by anti-Fas antibody, indicating these to be loss-of-function mutations. These findings suggested a role of Fas gene mutations in the pathogenesis of TGCTs.

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