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Dive into the research topics where Hiroto Hayashi is active.

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Featured researches published by Hiroto Hayashi.


Cancer Letters | 2000

Inhibitory effect of Coptidis Rhizoma and berberine on the proliferation of human esophageal cancer cell lines

Norio Iizuka; Koji Miyamoto; Kiwamu Okita; Akira Tangoku; Hiroto Hayashi; Shigehumi Yosino; Toshihiro Abe; Takayuki Morioka; Shoichi Hazama; Masaaki Oka

Our previous study demonstrated that the herbal medicine, Oren-to, had antitumor effects on esophageal cancer cells (ECCs) in vitro. The purpose of this study was to examine which of the seven constituents of Oren-to had antitumor effects on esophageal cancer cells. MTT assay showed that, of the seven constituents, only the aqueous extract of Coptidis Rhizoma had potent inhibitory effect on the proliferation of two types of ECC lines, YES-3 and YES-4. In addition, the proliferation of all six types of ECC lines (YES-1 to YES-6) was inhibited in a dose-dependent manner (P<0.001 for all), when co-cultured at each concentration of Coptidis Rhizoma for 72 h. The ID50 of Coptidis Rhizoma for YES-1 to YES-6 was 2.2 microg/ml, 3.0 microg/ml, 0.25 microg/ml, 2.8 microg/ml, 2.5 microg/ml, and 0.5 microg/ml, respectively, berberine, one of protoberberine components of Coptidis Rhizoma, showed potent antitumor effects on all six types of ECC lines as well as Coptidis Rhizoma. In addition, the ID50 of berberine showed a positive correlation with that of Coptidis Rhizoma in six types of ECC lines examined (r2 = 0.763, P = 0.023). Cell cycle analysis of Coptidis Rhizoma-treated cancer cells showed the accumulation of cells in the G0/G1 phase and relative decrease of the S phase. These results support the possibility that the use of Coptidis Rhizoma containing abundant berberine may be useful as one of alternative therapies for esophageal cancers.


Surgical Endoscopy and Other Interventional Techniques | 2004

Mediastinoscope-assisted transhiatal esophagectomy for esophageal cancer.

Akira Tangoku; Yoshino S; Toshihiro Abe; Hiroto Hayashi; T. Satou; Tomio Ueno; Oka M

Background: Transthoracic esophagectomy (TTE) is a radical strategy for treatment of esophageal cancer, and the morbidity and mortality are high. Transhiatal esophagectomy (THE) is advantageous because it avoids thoracotomy and has a shorter surgical time, but risk of intraoperative morbidity stresses the surgeon and lymph node sampling is not possible. Methods: Mediastinoscope-assited transhiatal esophagectomy (MATHE) was performed in 42 patients with esophageal cancer. Patients with superficial esophageal cancer and medical risk were included. Feasibility and efficacy of this procedure are discussed by examining short- and long-term morbidity, mortality, and survival. Results: With the mediastinoscope, esophagectomy was performed safely under direct vision. There was only a small amount of bleeding, and surgical time was short. Little morbidity and no deaths were recorded. Conclusion: MATHE is a safe and minimally invasive technique that allows direct visualization of mediastinal structures Lymph node sampling was feasible because of clear visualization of the mediastinum.


British Journal of Cancer | 1999

The nm23-H1 gene as a predictor of sensitivity to chemotherapeutic agents in oesophageal squamous cell carcinoma

Norio Iizuka; Kunitaka Hirose; Takafumi Noma; Hazama S; Akira Tangoku; Hiroto Hayashi; Toshihiro Abe; Koutaro Yamamoto; Masaaki Oka

SummaryRecently, nm23-H1, an anti-metastasis gene, has been reported to correlate with sensitivity to chemotherapeutic agents including cisplatin in human breast and ovarian carcinoma cells. The aim of this study was to evaluate a role for nm23-H1 in responsiveness to cisplatin-based chemotherapy in patients with oesophageal squamous cell carcinoma (OSCC). The expression of nm23-H1 protein was examined immunohistochemically in 32 eligible patients with OSCC who underwent adjuvant chemotherapy with cisplatin, etoposide, and 5-fluorouracil after tumour resection. Fifteen (46.9%) of 32 patients were positive for nm23-H1 staining and 17 (53.1%) were negative. Both disease-free survival and overall survival rates of nm23-H1-negative patients were significantly shorter than in nm23-H1-positive patients (P < 0.01 for both). There was no significant difference in clinicopathologic characteristics between nm23-H1-positive and nm23-H1-negative groups. Multivariate analysis also showed that nm23-H1 expression was the most significant factor for overall survival of OSCC patients included in this study (P = 0.0007). To further study the role of nm23-H1, a human OSCC cell line (YES-2) was transfected with a plasmid containing a fragment of the nm23-H1 cDNA in an antisense orientation. Reduced expression of nm23-H1 protein in the antisense-transfected (AS) clones was found by Western blot analysis as compared to wild-type YES-2 and YES-2/Neo (clone transfected with the neomycin resistance gene alone). MTT (3-(4,5-dimethyl-2-thiazol)-2,5-diphenyl-2H tetrazolium bromide) assay showed that reduced expression of the nm23-H1 protein in AS clones was consistent with the degree of increased resistance to cisplatin but not etoposide or 5-fluorouracil. These data support the conclusion that reduced expression of nm23-H1 may be associated with resistance to cisplatin, suggesting the value of nm23-H1 expression as a prognostic marker for OSCC patients who are to undergo cisplatin-based chemotherapy.


Cancer Genetics and Cytogenetics | 2000

Cytogenetic Analysis of Esophageal Squamous Cell Carcinoma Cell Lines by Comparative Genomic Hybridization: Relationship of Cytogenetic Aberrations to In Vitro Cell Growth

Kohsuke Tada; Masaaki Oka; Hiroto Hayashi; Akira Tangoku; Atsunori Oga

Cancer is characterized by autonomous growth of cells, and it is widely accepted that cell proliferation is primarily influenced by individual cell genetics. To elucidate the mechanisms of cancer cell proliferation, we studied differences in genetic aberrations for different type of tumors with different proliferation characteristics. We employed comparative genomic hybridization (CGH) to detect genetic aberrations in six cell lines of esophageal squamous cell carcinoma (ESCC). Three cell lines (YES-1, -2, and -3) grow in culture without fetal calf serum (group A), while others require serum to be maintained in vitro (group B). Both groups showed very similar cytogenetic aberrations: over-representations of 11q13 (6/6), 8q23-qter (5/6), Xq25-qter (5/6), 3q26-qter (4/6), 5p (4/6), 7p15-pter (4/6), 8q21.3-q22 (4/6), 17p (4/6), and 20q13 (4/6), and under-representations of 18q21-qter (6/6), 4q28-q33 (4/6), and 9p21 (4/6). Six amplification loci were mapped to chromosomal regions of 6q23 (1 case), 7p12 (2 cases), 9p21 (1 case), 11p11.2-12 (3 cases), 11q13 (2 cases), and 17p12 (2 cases). However, some differences were detected. DNA copy number increases at 7p12-p13, 11q14-q22, and 11q22-qter and under-representations of 4p, 8p, and 11p14-pter. In contrast, gains at 12p and 20p, and losses at 3p and 5q were detected only in group-B cell lines. These observations suggest that cytogenetic differences between the two groups may be linked to differences in cell growth characteristics in vitro, and that the genes in these chromosomal regions may play important roles in cell proliferation.


Journal of The American College of Surgeons | 2001

Interleukin-6 production in lung tissue after transthoracic esophagectomy

Toshihiro Abe; Masaaki Oka; Akira Tangoku; Hiroto Hayashi; Kohtarou Yamamoto; Noboru Yahara; Katsuhiko Morita; Tomoyuki Tabata; Yasukazu Ohmoto

BACKGROUND The mechanisms of the reported high increase in interleukin-6 (IL-6) levels after esophagectomy are unclear. We investigated the influence of an intrathoracic procedure, esophagectomy, on IL-6 production in lung tissue. STUDY DESIGN Fourteen paired lung tissue samples were obtained from patients before and after they underwent transthoracic esophagectomy for esophageal cancer. IL-6 levels in the lung were measured with enzyme-linked immunosorbent assay, and IL-6 mRNA expression was determined with real-time quantitative reverse transcription-polymerase chain reaction. Immunohistochemical staining was used to localize IL-6, and circulating levels were also measured. RESULTS IL-6 protein and mRNA were significantly increased in lung tissue after this intrathoracic procedure (p < 0.05). Peak levels of plasma IL-6 after surgery were correlated with IL-6 levels in lung tissues obtained after the procedure (p < 0.05). Immunohistochemical staining revealed IL-6 production from alveolar and bronchial epithelial cells but not from alveolar macrophages. CONCLUSIONS Transthoracic esophagectomy causes an increase in IL-6 production from airway epithelial cells, secondary to increased expression of IL-6 mRNA. Local response of lung tissue may be one source of increased serum IL-6 after this procedure.


British Journal of Cancer | 2000

Downregulation of intracellular nm23-H1 prevents cisplatin-induced DNA damage in oesophageal cancer cells: possible association with Na(+), K(+)-ATPase.

N lizuka; Koji Miyamoto; Akira Tangoku; Hiroto Hayashi; Hazama S; Yoshino S; Kiyoshi Yoshimura; Kunitaka Hirose; H Yoshida; Masaaki Oka

Previously, we showed that expression of nm23-H1 is associated inversely with sensitivity to cisplatin in human oesophageal squamous cell carcinoma (OSCC). The present study was undertaken to investigate the association of nm23-H1 expression with cisplatin-induced DNA damage in OSCC using antisense nm23-H1 transfectants. YES-2/AS-12, an antisense nm23-H1-transfected OSCC cell line, showed significantly reduced expression of intracellular nm23-H1 protein compared with that in parental YES-2 cells and YES-2/Neo transfectants. Surface expression of nm23-H1 protein was not observed in any of the three cell lines. PCR analysis for DNA damage demonstrated that YES-2/AS-12 cells were more resistant to nuclear and mitochondrial DNA damage by cisplatin than were YES-2/Neo cells. In addition, mitochondrial membrane potentials and DNA fragmentation assays confirmed that YES-2/AS-12 was more resistant than YES-2/Neo to apoptosis induced by cisplatin. In contrast, YES-2/AS-12 was more sensitive to ouabain, a selective inhibitor of Na+, K+-ATPase, than YES-2 and YES-2/Neo. Pre-treatment with ouabain resulted in no differences in cisplatin sensitivity between the three cell lines examined. Intracellular platinum level in YES-2/AS-12 was significantly lower than that in YES-2 and YES-2/Neo following incubation with cisplatin, whereas ouabain pre-treatment resulted in no differences in intracellular platinum accumulations between the three cell lines. Our data support the conclusion that reduced expression of intracellular nm23-H1 in OSCC cells is associated with cisplatin resistance via the prevention of both nuclear and mitochondrial DNA damage and suggest that it may be related to Na+, K+-ATPase activity, which is responsible for intracellular cisplatin accumulation.


Cancer Letters | 1999

The association between nm23-H1 expression and survival in patients with esophageal squamous cell carcinoma.

Norio Iizuka; Akira Tangoku; Hiroto Hayashi; Shigehumi Yosino; Toshihiro Abe; Takayuki Morioka; Masaaki Oka

The nm23 gene is a potential metastasis suppressor gene originally identified using a murine melanoma cell line. The expression of nm23-H1 protein was examined immunohistochemically in 50 eligible patients with esophageal squamous cell carcinoma (ESCC). The expression was not correlated with other prognostic factors including lymph node metastases; however, overall survival rates of nm23-H1-negative patients were significantly shorter than those of nm23-H1-positive patients (P < 0.05). Furthermore, reduced expression of nm23-H1 was associated with shorter overall survival in patients with involved lymph nodes (P < 0.01), but not in patients without involved lymph nodes. These data support the conclusion that reduced expression of nm23-H1 may be associated with poor prognosis of ESCC patients, suggesting the value of nm23-H1 expression as a prognostic marker for ESCC patients, especially ESCC patients with involved lymph nodes.


Cancer Science | 2017

Phase II clinical trial of peptide cocktail therapy for patients with advanced pancreatic cancer: VENUS-PC study

Nobuaki Suzuki; Shoichi Hazama; Haruo Iguchi; Kazuhiro Uesugi; Hiroaki Tanaka; Kosei Hirakawa; Atsushi Aruga; Takashi Hatori; Hidenobu Ishizaki; Yuzo Umeda; Toshiyoshi Fujiwara; Tetsuya Ikemoto; Mitsuo Shimada; Kazuhiko Yoshimatsu; Ryoichi Shimizu; Hiroto Hayashi; Koichiro Sakata; Hiroko Takenouchi; Hiroto Matsui; Yoshitaro Shindo; Michihisa Iida; Yasunobu Koki; Hideki Arima; Hiroyuki Furukawa; Tomio Ueno; Shigefumi Yoshino; Yusuke Nakamura; Masaaki Oka; Hiroaki Nagano

We previously conducted a phase I clinical trial combining the HLA‐A*2402‐restricted KIF20A‐derived peptide vaccine with gemcitabine for advanced pancreatic cancer (PC) and confirmed its safety and immunogenicity in cancer patients. In this study, we conducted a multicenter, single‐armed, phase II trial using two antiangiogenic cancer vaccines targeting VEGFR1 and VEGFR2 in addition to the KIF20A peptide. We attempted to evaluate the clinical benefit of the cancer vaccination in combination with gemcitabine. Chemotherapy naïve PC patients were enrolled to evaluate primarily the 1‐year survival rate, and secondarily overall survival (OS), progression free survival (PFS), response rate (RR), disease control rate (DCR) and the peptide‐specific immune responses. All enrolled patients received therapy without the HLA‐A information, and the HLA genotypes were used for classification of the patients. Between June 2012 and May 2013, a total of 68 patients were enrolled. No severe systemic adverse effects of Grade 3 or higher related to these three peptides were observed. The 1‐year survival rates between the HLA‐A*2402‐matched and ‐unmatched groups were not significantly different. In the HLA‐A*2402 matched group, patients showing peptide‐specific CTL induction for KIF20A or VEGFR1 showed a better prognosis compared to those without such induction (P = 0.023, P = 0.009, respectively). In the HLA‐A*2402‐matched group, the patients who showed a strong injection site reaction had a better survival rate (P = 0.017) compared to those with a weak or no injection site reaction. This phase II study demonstrated that this therapeutic peptide cocktail might be effective in patients who demonstrate peptide‐specific immune reactions although predictive biomarkers are needed for patient selection in its further clinical application.


Surgical Endoscopy and Other Interventional Techniques | 1999

Esophageal perforation and mediastinal abscess following placement of a covered self-expanding metallic stent and radiation therapy in a cancer patient.

Toshihiro Abe; Akira Tangoku; Hiroto Hayashi; Shigeru Takeda; Yoshino S; Oka M

Patients with advanced esophageal cancer may require intubation with a stent to relieve debilitating dysphagia. However, if these patients also undergo radiation therapy, they may incur esophageal injury, thus increasing the risk of perforation after placement of the stent. Herein we report the case of a 71-year-old man who received such combination therapy and died of severe sepsis 65 days after the stent was inserted. An autopsy revealed that the stent had perforated into the mediastinal pleura and that an abscess had developed around the perforation. We conclude that caution should be taken before combining radiation therapy with the use of a stent.


Surgery Today | 1996

Surgical stress and transient postoperative psychiatric disturbances in aged patients studied using the Yamaguchi University Mental Disorder Scale

Hiroto Hayashi; Yoshitaka Maeda; Hiroshi Morichika; Toshimune Miyama; Takashi Suzuki

Psychiatric disturbances often occur in aged patients after surgery, but there is no easy or precise method of predicting their occurrence. We devised an easy mental test, the Yamaguchi University Mental Disorder Scale (YDS), based on the surgical perspective. Using both this new method and the Hasegawa mental disorder scale (HDS), we examined 106 patients who had undergone general anesthesia. HDS only was used in 70 cases, while 36 cases were examined by the newly devised YDS and were then compared with the findings obtained by HDS. On the HDS examination, factors affecting postoperative psychiatric disturbances were, in order of frequency: entering the ICU, amount of bleeding, and duration of surgery. Aged patients who experienced severe surgical stress had a higher risk of developing transient postoperative psychiatric disturbances. On the YDS examination, the relationship between surgical stress and transient postoperative psychiatric disturbances was clearly indicated, as was the case with HDS. Postoperative delirium was seen in a significant proportion of patients with low preoperative scores on YDS (P<0.05), while no significant difference was observed between the mean preoperative scores on HDS and postoperative delirium. In the preoperative evaluation using YDS, postoperative delirium was found to be predictable, and YDS is thus considered to be a more valuable tool in managing aged patients.

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Oka M

Yamaguchi University

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Tomio Ueno

Kawasaki Medical School

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