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Dive into the research topics where Hiroki Ochiai is active.

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Featured researches published by Hiroki Ochiai.


Inflammatory Bowel Diseases | 2008

Efficacy of infliximab for induction and maintenance of remission in intestinal Behçet's disease

Makoto Naganuma; Atsushi Sakuraba; Tadakazu Hisamatsu; Hiroki Ochiai; Hirotoshi Hasegawa; Haruhiko Ogata; Yasushi Iwao; Toshifumi Hibi

Background: Intestinal Behçet disease (BD) is characterized by intestinal inflammation with round and oval ulcers associated with gastrointestinal symptoms. Although several cases have been reported that infliximab is effective for induction of remission, the efficacy of infliximab for maintaining remission is unknown. Methods: Six cases with fulminant intestinal BD were treated with infliximab. All patients were steroid‐dependent and refractory to immunosuppressants; 3 patients were treated with 6‐mercaptopurine, 1 patient with azathioprine, 1 patient with cyclosporine A, and 1 patient with methotrexate. Results: Four patients achieved remission by infliximab and all of these patients maintained remission with scheduled treatments of infliximab, with the longest duration of remission being about 3 years. Another 2 patients with ileal ulceration required surgery; however, 1 patient has maintained remission by scheduled treatment of infliximab for 2 years after surgery. Conclusions: Infliximab appears to offer an option for fulminant intestinal BD to induce and maintain remission, although a randomized control trial is needed.


Ejso | 2010

Medium-term results of neoadjuvant systemic chemotherapy using irinotecan, 5-fluorouracil, and leucovorin in patients with locally advanced rectal cancer

Yoshiyuki Ishii; Hirotoshi Hasegawa; Takashi Endo; Koji Okabayashi; Hiroki Ochiai; Konosuke Moritani; Masahiko Watanabe; Yuko Kitagawa

AIMS The aim of this study was to evaluate the usefulness of neoadjuvant systemic chemotherapy using irinotecan, 5-FU, and leucovorin (LV) for the treatment of locally advanced rectal cancer, which was a powerful ploychemotherapy in those days in Japan. METHODS Between 2001 and 2004, 26 patients with T3 or T4 and N0-2 non-metastatic resectable rectal cancer were selectively enrolled in this study. Neoadjuvant chemotherapy consisted of two cycles of irinotecan (80 mg/m²), 5-FU (500 mg/m²), and LV (250 mg/m²) on days 1, 8, and 15 for 4 weeks. Surgical resection was performed in all the patients 2-4 weeks after the completion of chemotherapy. RESULTS Overall down-staging was observed in 15 patients. T level and N level down-staging were observed in 12 and 13 patients, respectively. A pathological complete response was observed in one patients. The median follow-up period was 75 months (range, 8-97 months). Recurrences occurred in 5 patients including pelvic relapses in 3 and distant metastases in 2. The 5-year relapse-free and overall survival rates were 74% and 84%, respectively. CONCLUSIONS Neoadjuvant systemic chemotherapy comprised of a combination of multi-drugs as irinotecan, 5-FU, and LV may be beneficial to the prognoses of patients with locally advanced rectal cancer.


Oncology | 2008

A New Formula for Predicting Liver Metastasis in Patients with Colorectal Cancer: Immunohistochemical Analysis of a Large Series of 439 Surgically Resected Cases

Hiroki Ochiai; Yukihiro Nakanishi; Yuri Fukasawa; Yasunori Sato; Kimio Yoshimura; Yoshihiro Moriya; Yae Kanai; Masahiko Watanabe; Hirotoshi Hasegawa; Yuko Kitagawa; Masaki Kitajima; Setsuo Hirohashi

Objective: The purpose of this study was to establish a new formula predicting liver metastasis in patients with colorectal cancer (CRC). Methods: Nine previously reported predictive markers for liver metastasis and/or prognosis (COX-2, dysadherin, E-cadherin, β-catenin, Ki-67, p53, laminin5γ2, matrilysin and MUC-1) were immunohistochemically investigated in 439 consecutive patients with CRC. We tried to determine the combination of molecules which best predicted liver metastasis. A formula for predicting liver metastasis was constructed using a training cohort comprising 150 cases, and applied to a validation cohort comprising 190 cases and another comprising 99 cases from an outside hospital. Results: A combination of dysadherin, E-cadherin and matrilysin was identified to be best for predicting liver metastasis (area under the curve value, 0.807). The predictive formula: 3× dysadherin score [0 for low expression (≤50% of tumor cells positive) or 1 for high expression (>50%)] + 4× E-cadherin score [0 for preserved (>80% of tumor cells positive) or 1 for reduced (≤80%)] + 2× matrilysin score [0 for low expression (≤30% of tumor cells positive) or 1 for high expression (>30%)] was able to discriminate patients with liver metastasis in the training cohort with a sensitivity of 85.7% and a specificity of 58.9%. The discriminative capacity of the formula was validated in the first cohort with a sensitivity of 87.0% and a specificity of 66.5%, and in the second cohort with a sensitivity of 80% and a specificity of 60.0%. Conclusions: We have established a formula for predicting liver metastasis in patients with CRC, and confirmed that it has a high sensitivity potentially useful for clinical application.


Oncology Reports | 2014

Cetuximab-mediated ADCC activity is correlated with the cell surface expression level of EGFR but not with the KRAS/BRAF mutational status in colorectal cancer

Yuki Seo; Yoshiyuki Ishii; Hiroki Ochiai; Kazumasa Fukuda; Shingo Akimoto; Tetsu Hayashida; Koji Okabayashi; Masashi Tsuruta; Hirotoshi Hasegawa; Yuko Kitagawa

Cetuximab, an IgG1 monoclonal antibody against the epidermal growth factor receptor (EGFR), is widely used for the treatment of metastatic colorectal cancer (mCRC). One of the mechanisms of action is considered to be antibody-dependent cell-mediated cytotoxicity (ADCC) triggered by Fcγ-R on natural killer cells. However, whether ADCC is associated with EGFR expression and/or the mutational status of EGF downstream effectors (KRAS and BRAF) in colorectal cancer (CRC) remains unclear. The aim of the present study was to verify whether ADCC activities are associated with the cell surface expression levels of EGFR and/or the mutational status of KRAS and BRAF. Five human CRC cell lines with different cell surface expression levels of EGFR and different KRAS and BRAF mutational statuses were selected to evaluate ADCC activity using peripheral blood mononuclear cells (PBMCs) from healthy human donors. Furthermore, tumor cells from resected specimens of CRC patients were used to evaluate the cell surface expression level of EGFR using immunohistochemistry and the KRAS and BRAF mutational statuses using direct sequencing, while the ADCC activity was examined using PBMCs from the same CRC patients. A strong correlation was observed between the expression levels of EGFR and the ADCC activities in the cell lines (correlation coefficient: 0.949; P=0.003). Of the 13 resected specimens, a high ADCC activity level was significantly observed in tumor cells with high expression levels of cell surface EGFR, when compared with that in the tumor cells with low expression levels (P=0.027). In both CRC cell lines and tumor cells from CRC patients, the ADCC activities were significantly associated with the cell surface expression levels of EGFR [standard partial regression coefficients: 0.911 (P=0.017) and 0.660 (P=0.018), respectively], but not with the mutational status of KRAS and BRAF [standard partial regression coefficient: -0.101 (P=0.631) and 0.160 (P=0.510), respectively]. Cetuximab-mediated ADCC activity may be correlated with the cell surface expression level of EGFR, regardless of the mutational statuses of KRAS and BRAF, in CRC.


Surgical Laparoscopy Endoscopy & Percutaneous Techniques | 2009

Hand-assisted Versus Conventional Laparoscopic Restorative Proctocolectomy for Ulcerative Colitis

Masashi Tsuruta; Hirotoshi Hasegawa; Yoshiyuki Ishii; Takashi Endo; Hiroki Ochiai; Toshifumi Hibi; Yuko Kitagawa

Aim In a few comparative and randomized studies, hand-assisted laparoscopic restorative proctocolectomy (HALS-RP) maintained the advantages of a minimally invasive approach with some potential benefits. However, the role of HALS-RP has not been defined. The aim of this study was to evaluate the effectiveness of HALS-RP compared with a conventional laparoscopic restorative proctocolectomy (LAP-RP) in patients with ulcerative colitis. Methods A retrospective study was conducted using a prospectively maintained database to compare a consecutive series of 30 patients who underwent HALS-RP from June 2004 to September 2007 with 40 patients who underwent LAP-RP from October 1994 to June 2004 in our institution. Patient characteristics, perioperative parameters, and the surgical outcomes were assessed. Mann-Whitney U and Fisher exact tests were used for statistical analysis. Results Both groups were well matched with no differences in sex, body mass index, periods from diagnosis, American Society of Anesthesiologists score, performance status, preoperative blood chemistry or steroid, and cyclosporine usage. The median operative time was significantly shorter for HALS-RP [356 (range: 176 to 590) min] than for LAP-RP [505 (range: 360 to 785) min; P<0.001]. The median length of incision was significantly longer for HALS-RP [8 (range: 7.5 to 8) cm] than for LAP-RP [5.5 (range: 5 to 8) cm]. The estimated blood loss and the length of hospital stay were similar between the 2 groups. The incidence of postoperative complications including anastomotic leakage did not differ between the 2 groups (P=0.437). Conclusions HALS-RP significantly reduced the operative time compared with the conventional LAP-RP, while retaining the acceptable morbidity rates and recovery benefits associated with minimally invasive surgery. HALS-RP is likely to replace a conventional laparoscopic approach for this technically challenging procedure.


International Journal of Clinical Oncology | 2012

Two cases of bowel perforation associated with sunitinib treatment for renal cell carcinoma

Yoshinori Hoshino; Hirotoshi Hasegawa; Yoshiyuki Ishii; Takashi Endo; Hiroki Ochiai; Koji Okabayashi; Gou Kaneko; Shuji Mikami; Makio Mukai; Mototsugu Oya; Yuko Kitagawa

Sunitinib, a multitargeted tyrosine kinase inhibitor, is widely used in the treatment of carcinoma. Adverse events associated with this treatment, including fatigue, diarrhea, and hematotoxicity, have been reported in clinical trials. Bowel perforation is a surgical emergency that requires immediate treatment depending on the location and progression of the tumor. We report 2 cases of bowel perforation during sunitinib treatment. The patients presented with diffuse peritonitis, and emergency exploratory laparotomy was performed. We speculate that the underlying mechanisms were decrease in capillary density of the normal mucosa in case 1 and tumor shrinkage because of sunitinib treatment in case 2. To the best of our knowledge, this is the first study to report the pathological findings implicating bowel perforation due to sunitinib treatment. Further investigations are needed to clarify the risk factors for intestinal perforations associated with sunitinib treatment.


American Journal of Pathology | 2013

Src Plays a Key Role in ADAM28 Expression in v-src–Transformed Epithelial Cells and Human Carcinoma Cells

Hitoshi Abe; Satsuki Mochizuki; Kentaro Ohara; Mari Ueno; Hiroki Ochiai; Yuko Kitagawa; Okio Hino; Hiroshi Sato; Yasunori Okada

ADAM28, a disintegrin and metalloproteinase 28, is overexpressed by carcinoma cells with direct correlations with carcinoma cell proliferation and progression in human lung and breast carcinomas. However, the molecular mechanisms of ADAM28 gene expression in carcinoma cells remain elusive. Herein, we investigated the expression of ADAM28 in Madin-Darby canine kidney epithelial cells transformed by oncogenes, including v-src, LMP1, ErbB2, Ha-Ras, and c-Fos, and found that v-src transformants selectively induce ADAM28. Implantation of the v-src transformants showed a progressively growing tumor, which was significantly suppressed by local injections of anti-ADAM28 antibody. ADAM28 expression in v-src transformants was partially inhibited by treatment with inhibitors to Src kinase, mitogen-activated protein kinase kinase (MEK), phosphatidylinositol 3-kinase (PI3K), or mammalian target of rapamycin, and abrogated by v-Src kinase inhibitor, radicicol, or a mixture of MEK and PI3K inhibitors. Human carcinoma cell lines of the lung, breast, ovary, kidney, and colon showed ADAM28 expression, which was correlated with phosphorylation of c-Src and suppressed by the inhibitors in a similar way to v-src transformants. IHC of the human tumor tissues demonstrated co-expression of ADAM28 and phosphorylated Src in neoplastic cells of the breast, lung, and colon carcinomas and some adenomas of the colon, but not in nonneoplastic colon mucosa. Our data provide, to the best of our knowledge, the first evidence that Src is an inducer of ADAM28 gene expression through the MEK/extracellular signal-regulated kinase and PI3K/mammalian target of rapamycin pathways.


International Journal of Cancer | 2016

Randomized phase II trial of TEGAFIRI (tegafur/uracil, oral leucovorin, irinotecan) compared with FOLFIRI (folinic acid, 5-fluorouracil, irinotecan) in patients with unresectable/recurrent colorectal cancer

Kohei Shigeta; Hirotoshi Hasegawa; Koji Okabayashi; Masashi Tsuruta; Yoshiyuki Ishii; Takashi Endo; Hiroki Ochiai; Takayuki Kondo; Yuko Kitagawa

Irinotecan‐based chemotherapy with bevacizumab is one of the first‐line standard therapies for metastatic colorectal cancer (mCRC). TEGAFIRI (UFT/LV + irinotecan) is an irinotecan‐based chemotherapy regimen. Currently, few clinical data regarding TEGAFIRI are available. This study evaluated the efficacy and safety of TEGAFIRI in Japanese patients with mCRC. This is a multicenter, randomized, phase II study. The major inclusion criteria were previously untreated patients with mCRC (age: 20–75 years, Eastern Cooperative Oncology Group performance status: 0–1). Eligible patients were randomly assigned (1:1) to receive either FOLFIRI ± bevacizumab or TEGAFIRI ± bevacizumab. The primary endpoint was progression‐free survival (PFS). The secondary endpoints were response rate, overall survival, dose intensity and toxicity. From November 2007 to October 2011, 36 and 35 patients assigned to the FOLFIRI and TEGAFIRI groups were included in the primary analysis. No significant difference in PFS was observed between the groups {median PFS: TEGAFIRI 9.9 months [95% confidence interval (CI), 6.5–14.7], FOLFIRI 10.6 months [95% CI, 7.7–16.5]; Hazard ratio, 0.98, 95% CI, 0.57–1.66, p = 0.930}. The response rates in the FOLFIRI and TEGAFIRI groups were 56% and 66%, respectively. Relative dose intensity was similar between the groups. The most common Grade 3/4 adverse event was diarrhea (26%) in TEGAFIRI group and neutropenia (39%) in the FOLFIRI group. The results of the present study indicate that TEGAFIRI ± bevacizumab is an effective and tolerable first‐line treatment regimen for mCRC.


Case Reports in Gastroenterology | 2010

Prolapse of Intussusception through the Anus as a Result of Sigmoid Colon Cancer

Hiroki Ochiai; Takashi Ohishi; Shikou Seki; Koji Osumi; Hidejirou Urakami; Atsushi Shimada; Akira Matsui; Yoh Isobe; Yuya Murata; Takashi Endo; Yoshiyuki Ishii; Hirotoshi Hasegawa; Sumio Matsumoto; Yuko Kitagawa

Adult intussusception is rare and most often associated with cancer. We report a case of intussuscepted sigmoid colon into the rectum protruding from the anus of a 47-year-old woman. The cause of the intussusception was sigmoid colon cancer. We removed the intussuscepted part of the sigmoid colon as well as the rectum and regional lymph nodes. The patient recovered uneventfully and there has been no evidence of recurrence of the cancer.


FEBS Journal | 2016

ADAM28 is expressed by epithelial cells in human normal tissues and protects from C1q‐induced cell death

Yuka Miyamae; Satsuki Mochizuki; Masayuki Shimoda; Kentaro Ohara; Hitoshi Abe; Shuji Yamashita; Saiko Kazuno; Takashi Ohtsuka; Hiroki Ochiai; Yuko Kitagawa; Yasunori Okada

ADAM28 (disintegrin and metalloproteinase 28), which was originally reported to be lymphocyte‐specific, is over‐expressed by carcinoma cells and plays a key role in cell proliferation and progression in human lung and breast carcinomas. We studied ADAM28 expression in human normal tissues and examined its biological function. By using antibodies specific to ADAM28, ADAM28 was immunolocalized mainly to epithelial cells in several tissues, including epididymis, bronchus and stomach, whereas lymphocytes in lymph nodes and spleen were negligibly immunostained. RT‐PCR, immunoblotting and ELISA analyses confirmed the expression in these tissues, and low or negligible expression by lymphocytes was found in the lymph node and spleen. C1q was identified as a candidate ADAM28‐binding protein from a human lung cDNA library by yeast two‐hybrid system, and specific binding was demonstrated by binding assays, immunoprecipitation and surface plasmon resonance. C1q treatment of normal bronchial epithelial BEAS‐2B and NHBE cells, both of which showed low‐level expression of ADAM28, caused apoptosis through activation of p38 and caspase‐3, and cell death with autophagy through accumulation of LC3‐II and autophagosomes, respectively. C1q‐induced cell death was attenuated by treatment of the cells with antibodies against the C1q receptor gC1qR/p33 or cC1qR/calreticulin. Treatment of C1q with recombinant ADAM28 prior to addition to culture media reduced C1q‐induced cell death, and knockdown of ADAM28 using siRNAs increased cell death. These data demonstrate that ADAM28 is expressed by epithelial cells of several normal organs, and suggest that ADAM28 plays a role in cell survival by suppression of C1q‐induced cytotoxicity in bronchial epithelial cells.

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