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Featured researches published by Yohei Ozawa.


World Journal of Surgical Oncology | 2013

Significance of CD133 expression in esophageal squamous cell carcinoma

Hiroshi Okamoto; Fumiyoshi Fujishima; Yasuhiro Nakamura; Masashi Zuguchi; Yohei Ozawa; Yayoi Takahashi; Go Miyata; Takashi Kamei; Toru Nakano; Yusuke Taniyama; Jin Teshima; Mika Watanabe; Akira Sato; Noriaki Ohuchi; Hironobu Sasano

BackgroundCD133 was recently reported to be a cancer stem cell marker and a prognostic marker for several tumors. However, few studies have investigated CD133 expression in esophageal squamous cell carcinoma (ESCC). Therefore, we examined whether CD133 could serve as a prognostic marker of ESCC and investigated the correlation between CD133 expression and the clinicopathological findings of ESCC patients and several markers.MethodsWe studied 86 ESCC patients who underwent curative surgery without neoadjuvant treatment at Tohoku University Hospital (Sendai, Japan) between January 2000 and December 2005. We analyzed tissue specimens by immunohistochemical staining for CD133, p53, p16, p27, murine double minute 2 (MDM2), Ki-67, and epidermal growth factor receptor (EGFR).ResultsPathological tumor depth and tumor stage were significantly more advanced among CD133-negative patients than among CD133-positive patients. A log-rank test showed that CD133 immunoreactivity was significantly correlated with the overall survival of the patients (P = 0.049). However, multivariate analysis showed that it was not significantly correlated (P = 0.078). Moreover, CD133 was significantly positively correlated with p27 immunoreactivity (P = 0.0013) and tended to be positively correlated with p16 immunoreactivity (P = 0.057). In addition, p16 immunoreactivity was correlated with smoking history (P = 0.018), pathological lymph node status (P = 0.033), and lymphatic invasion (P = 0.018).ConclusionsThis study indicated that CD133 immunoreactivity is a good predictor of prognosis in ESCC patients. In addition, CD133 may play a role in the regulation of tumor cell cycle through p27 and p16 in ESCC. At present, it thus remains controversial whether CD133 expression is a valid prognostic marker for ESCC. To elucidate this relationship, further investigations are required.


The Journal of Steroid Biochemistry and Molecular Biology | 2014

Steroidogenic enzymes, their related transcription factors and nuclear receptors in human sebaceous glands under normal and pathological conditions

Abdullah Azmahani; Yasuhiro Nakamura; Saulo J.A. Felizola; Yohei Ozawa; Kazue Ise; Takayoshi Inoue; Keely May McNamara; Masao Doi; Hitoshi Okamura; Christos C. Zouboulis; Setsuya Aiba; Hironobu Sasano

The sebaceous gland is a major site of steroid synthesis in human skin, but details of the status of steroidogenic enzymes and their regulation in human sebaceous glands under normal and pathological conditions have rarely been reported. Therefore, in this study, we examined the status of steroidogenic enzymes, sex steroid receptors and transcription factors in human sebaceous glands under normal and pathological conditions to explore their possible roles in in situ steroid production in human skin. Immunohistochemical analysis was performed in a total of 59 human skin specimens, including 22 normal human sebaceous glands, 12 with sebaceous nevus, 12 with sebaceous gland hyperplasia, 3 with sebaceoma and 10 with sebaceous carcinoma. Immortalised human SZ95 sebocytes were treated with forskolin or vehicle for 3h, 6h, 12h or 24h, and the mRNA levels of steroidogenic enzymes were evaluated at each time point using quantitative RT-PCR (qPCR). The results of immunohistochemistry demonstrated the immunoreactivity of 3β-HSD1, CYP11A1, StAR, 17β-HSD5, CYP17A1, 5α-red1, PRB, AR and NGFI-B in normal human sebaceous gland, with lower levels of expression in pathological sebaceous glands. The results of the in vitro study also indicated that the expression levels of 3β-HSD1, CYP11A1, StAR, 5α-red1 and NGFI-B were elevated by forskolin. 3β-HSD1 and other steroidogenic enzymes were expressed in sebaceous glands resulting in in situ androgen and progesterone synthesis and their functions.


BMC Cancer | 2015

c-Met in esophageal squamous cell carcinoma: an independent prognostic factor and potential therapeutic target

Yohei Ozawa; Yasuhiro Nakamura; Fumiyoshi Fujishima; Saulo J.A. Felizola; Kenichiro Takeda; Hiroshi Okamoto; Ken Ito; Hirotaka Ishida; Takuro Konno; Takashi Kamei; Go Miyata; Noriaki Ohuchi; Hironobu Sasano

Backgroundc-Met is widely known as a poor prognostic factor in various human malignancies. Previous studies have suggested the involvement of c-Met and/or its ligand, hepatocyte growth factor (HGF), in esophageal squamous cell carcinoma (ESCC), but the correlation between c-Met status and clinical outcome remains unclear. Furthermore, the identification of a novel molecular therapeutic target might potentially help improve the clinical outcome of ESCC patients.MethodsThe expression of c-Met and HGF was immunohistochemically assessed in 104 surgically obtained tissue specimens. The correlation between c-Met/HGF expression and patients’ clinicopathological features, including survival, was evaluated. We also investigated changes in cell functions and protein expression of c-Met and its downstream signaling pathway components under treatments with HGF and/or c-Met inhibitor in ESCC cell lines.ResultsElevated expression of c-Met was significantly correlated with tumor depth and pathological stage. Patients with high c-Met expression had significantly worse survival. In addition, multivariate analysis identified the high expression of c-Met as an independent prognostic factor. Treatment with c-Met inhibitor under HGF stimulation significantly inhibited the invasive capacity of an ESCC cell line with elevated c-Met mRNA expression. Moreover, c-Met and its downstream signaling inactivation was also detected after treatment with c-Met inhibitor.ConclusionsThe results of our study identified c-Met expression as an independent prognostic factor in ESCC patients and demonstrated that c-Met could be a potential molecular therapeutic target for the treatment of ESCC with elevated c-Met expression.


World Journal of Gastroenterology | 2015

Indocyanine green fluorescence and three-dimensional imaging of right gastroepiploic artery in gastric tube cancer

Toru Nakano; Tadashi Sakurai; Shota Maruyama; Yohei Ozawa; Takashi Kamei; Go Miyata; Noriaki Ohuchi

A 79-year-old male was admitted to our hospital for the treatment of cancer of the gastric tube. Gastrointestinal examination revealed a T1b Union for International Cancer Control (UICC) tumor at the pyloric region of the gastric tube. Laparotomy did not reveal infiltration into the serosa, peritoneal dissemination, regional lymph node swelling, or distant metastasis. We performed a distal gastrectomy preserving the right gastroepiploic artery by referencing the preoperative three-dimensional computed tomoangiography. We also evaluated the blood flow of the right gastroepiploic artery and in the proximal gastric tube by using indocyanine green fluorescence imaging intra-operatively and then followed with a gastrojejunal anastomosis with Roux-en-Y reconstruction. The definitive diagnosis was moderately differentiated adenocarcinoma of the gastric tube, pT1bN0M0, pStage IA (UICC). His postoperative course was uneventful. Three-dimensional computed tomographic imaging is effective for assessing the course of blood vessels and the relationship with the surrounding structures. Intraoperative evaluation of blood flow of the right gastroepiploic artery and of the gastric tube in the anastomotic portion is very valuable information and could contribute to a safe gastrointestinal reconstruction.


Tohoku Journal of Experimental Medicine | 2015

Decreased expression of ARID1A contributes to infiltrative growth of esophageal squamous cell carcinoma.

Yohei Ozawa; Yasuhiro Nakamura; Fumiyoshi Fujishima; Saulo J.A. Felizola; Kenichiro Takeda; Hiroshi Okamoto; Ken Ito; Hirotaka Ishida; Takuro Konno; Takashi Kamei; Noriaki Ohuchi; Hironobu Sasano

The clinical outcome for esophageal squamous cell carcinoma (ESCC) patients is often poor because of the invasive nature of this tumor type. AT-rich interactive domain 1A (ARID1A) functions as a tumor suppressor, and its gene mutation has been reported in various human malignancies. ARID1A is a non-catalytic subunit of the SWItch/Sucrose Non Fermentable (SWI/SNF) chromatin-remodeling complex that regulates gene transcription. Decreased expression of ARID1A protein has been reported to decrease the expression of E-cadherin, an adhesion protein. However, the correlation between ARID1A and E-cadherin expression status in ESCC remains largely unknown. To address this issue, we examined the expression of ARID1A and E-cadherin in tumor specimens excised from 83 ESCC patients using immunohistochemical analysis. The intensity of the ARID1A immunoreactivity was significantly lower in tumors with a growth pattern characterized by ill-defined borders than that in tumors with an expansive growth pattern having a well-demarcated border or tumors with an intermediate growth pattern. Thus, decreased ARID1A immunoreactivity correlated with infiltrative growth of ESCC. In contrast, E-cadherin status did not correlate with the infiltrative growth pattern of ESCC. Moreover, ARID1A expression status did not significantly correlate with any of other clinicopathological factors, E-cadherin expression levels, or the clinical outcome of the patients. On the other hand, the patients with tumors expressing low levels of E-cadherin exhibited significantly lower survival rates than those with high expression. In conclusion, reduced ARID1A expression in tumor tissues contributes to infiltrative growth of ESCC, irrespective of E-cadherin expression levels.


Human Pathology | 2015

Androgen receptor, androgen-producing enzymes and their transcription factors in extramammary Paget disease

Abdullah Azmahani; Yasuhiro Nakamura; Yohei Ozawa; Keely May McNamara; Taku Fujimura; Takahiro Haga; Akira Hashimoto; Setsuya Aiba; Hironobu Sasano

Extramammary Paget disease (EMPD) has been known to frequently express androgen receptor (AR). Therefore, androgens could play roles in the biological behavior of Paget cells. 5α-Reductase (5α-red) types 1 and 2 and 17β-hydroxysteroid dehydrogenase type 5 (17β-HSD5) are pivotal in situ regulators of androgen production in androgen-responsive tissues including androgen-dependent neoplasms. Therefore, in this study, we immunolocalized AR, androgen-producing enzymes, and their transcription factors to assess the state of in situ androgen production and actions and its correlation of invasiveness in EMPD. We studied 51 cases of EMPD with known clinicopathological status. AR, 5α-red1, 17β-HSD5, and β-catenin immunoreactivity was evaluated by using the modified H-score method while cyclin D1, p53, forkhead box protein P1, and a proliferation marker, Ki-67, were quantified using labeling index. The mean scores of AR, 5α-red1, and 17β-HSD5 in invasive EMPD were all significantly higher than noninvasive EMPD (P < .0001). Ki-67 labeling index as well as the cyclin D1 score was also significantly higher in invasive than noninvasive lesions of EMPD. These results demonstrated that androgen receptor and androgen-producing enzymes were both associated with cell cycle regulation and subsequently the invasiveness of EMPD lesions and could also indicate those above as potential markers of invasive potentials in EMPD.


Diseases of The Esophagus | 2018

Residual carcinoma cells after chemoradiotherapy for esophageal squamous cell carcinoma patients: striving toward appropriate judgment of biopsy

Fumiyoshi Fujishima; Yusuke Taniyama; Y Nakamura; Hiroshi Okamoto; Yohei Ozawa; Ken Ito; Hirotaka Ishida; T Konno-Kumagai; A Kasajima; Shinji Taniuchi; Mika Watanabe; Takashi Kamei; Hironobu Sasano

In esophageal squamous cell carcinoma (ESCC) patients who are treated with chemoradiotherapy (CRT), identification of the presence or absence of residual or recurrent carcinoma is usually pivotal in their clinical management. In addition, the extent of carcinoma invasion into the esophageal wall could determine the clinical outcome of these patients following CRT. Therefore, in this study, we evaluated the response to CRT both macroscopically and histologically in a consecutive series of 42 ESCC patients receiving neoadjuvant chemoradiotherapy following curative esophageal resection at Tohoku University Hospital between August 2011 and December 2012. The histological grading of tumor regression was as follows: grade 3, markedly effective (no viable residual tumor cells); grade 2, moderately effective (residual tumor cells in less than one-third of the tumor); grade 1, slightly effective (1b, residual tumor cells in one-third to two-thirds of the tumor; 1a, residual tumor cells in more than two-thirds of the tumor); and grade 0, ineffective. In this study, we selected grade 2 and 1b cases because they might show a complete response with definitive CRT. We evaluated the presence of any residual in situ lesions and tumor depth in detail. The grading of tumor regression in primary sites was as follows: grade 3 (7 cases), grade 2 (16 cases), grade 1b (13 cases), and grade 1a (6 cases). The concordance rate between macroscopic and histopathological evaluation on the depth of the tumor was 40% (17/42). Among 29 cases (grade 2 and grade 1b), intraepithelial lesions were not detected in 17 cases, and tumor nests were not detected in the lamina propria mucosae in 9 cases. The results of this study highlight the difficulties of detecting residual carcinoma cells using conventional endoscopic biopsy in patients who have received CRT. Therefore, when residual cancer is clinically suspected in patients who have received CRT, the biopsy specimen should be obtained from the deep layer of the esophagus whenever possible. Additionally, close follow-up is required using positron emission tomography/computed tomography, endoscopy, and other radiological evaluations.


The Journal of Steroid Biochemistry and Molecular Biology | 2016

Reply to comments to "Letter to the Editor: comment on Azmahani et al. steroidogenic enzymes, their related transcription factors and nuclear receptors in human sebaceous glands under normal and pathological conditions".

Abdullah Azmahani; Yasuhiro Nakamura; Saulo J.A. Felizola; Yohei Ozawa; Kazue Ise; Takayoshi Inoue; Keely May McNamara; Masao Doi; Hitoshi Okamura; Christos C. Zouboulis; Setsuya Aiba; Hironobu Sasano

Department of Pathology, Tohoku University Graduate School of Medicine, Sendai, Japan b Faculty of Medicine and Health Sciences, University Sultan Zainal Abidin, Kuala Terengganu, Terengganu, Malaysia Division of Advanced Surgical Science and Technology, Tohoku University Graduate School of Medicine, Sendai, Japan Biological Science Laboratories, Kao Corporation, Haga, Tochigi, Japan Department of Systems Biology, School of Pharmaceutical Sciences, Kyoto University, Kyoto 606, Japan Departments of Dermatology, Venereology, Allergology and Immunology, Dessau Medical Center, Dessau, Germany Department of Dermatology, Tohoku University Graduate School of Medicine, Sendai, Japan


Esophagus | 2015

Adenocarcinoma in the squamous‑lined esophagus without Barrett's mucosa, probably arising from esophageal gland duct

Fumiyoshi Fujishima; Yasuhiro Nakamura; Atsuko Kasajima; Yohei Ozawa; Ken Ito; Shinji Taniuchi; Mika Watanabe; Sho Asonuma; Kaiyo Takubo; Hironobu Sasano

Abstract Endoscopic mucosal resection (EMR) was performed for submucosal tumor (SMT)-like lesion of esophagogastric junction in an 81-year-old male. Histopathological findings revealed the presence of adenocarcinoma with high-grade cytological atypia. No foci of Barrett’s esophagus and/or heterotopic gastric mucosa were detected in the specimen. Intraepithelial squamous cell carcinoma was also not detected in the adjacent stratified squamous layer. The contour of the tumor was similar to normal esophageal gland ducts but tumor did have immunohistochemical staining patterns similar to esophageal cardiac glands. Esophageal adenocarcinoma arising in the background without the foci of Barrett’s esophagus is extremely rare and we reported the case with review of the literature in this study.


Human Pathology | 2018

Myosin 5a regulates tumor migration and epithelial-mesenchymal transition in esophageal squamous cell carcinoma: utility as a prognostic factor

Naomi Sato; Fumiyoshi Fujishima; Yasuhiro Nakamura; Yayoi Aoyama; Yoshiaki Onodera; Yohei Ozawa; Ken Ito; Hirotaka Ishida; Takashi Kamei; Mika Watanabe; Hironobu Sasano

Esophageal squamous cell carcinoma (ESCC) is highly malignant. Recently, the expression of myosin 5a, a member of the myosin superfamily, was reported to be associated with increased invasiveness and metastasis in many tumor types. Moreover, myosin 5a is upregulated by Snail and activated by Akt2, both of which are epithelial-mesenchymal transition (EMT) markers. In this study, we confirmed the expression of myosin 5a in ESCC surgical specimens and cell lines, revealing its correlation with tumor invasion, migration, patient prognosis, and expression of EMT-related proteins. The expression of myosin 5a, vimentin, and E-cadherin was immunohistochemically evaluated in 118 patients with ESCC who underwent esophagectomy without chemotherapy or irradiation therapy prior to surgery. We also investigated ESCC cell migration under myosin 5a silencing by siRNA induction. The high expression of myosin 5a was correlated with tumor depth, lymph node metastasis, pathological stage, high vimentin expression, and low E-cadherin expression. Patients with high expression of myosin 5a, including those with pT1 cancer, exhibited significantly worse survival. Moreover, the expression level of vimentin mRNA and the number of migrated ESCC cells decreased significantly following myosin 5a silencing. Our findings demonstrate that high expression of myosin 5a may be an independent prognostic factor in patients with ESCC, even in early invasive carcinoma, and indicate myosin 5a has a role in both cell migration and EMT.

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