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Featured researches published by Yu Nakaji.


Annals of Surgery | 2017

Prognostic Significance of Postoperative Complications After Curative Resection for Patients With Esophageal Squamous Cell Carcinoma.

Hiroshi Saeki; Satoshi Tsutsumi; Hirotada Tajiri; Takafumi Yukaya; Ryosuke Tsutsumi; Sho Nishimura; Yu Nakaji; Kensuke Kudou; Shingo Akiyama; Yuta Kasagi; Ryota Nakanishi; Yuichiro Nakashima; Masahiko Sugiyama; Kippei Ohgaki; Hideto Sonoda; Eiji Oki; Yoshihiko Maehara

Objective: The objective of this study was to elucidate the impact of postoperative complications on long-term survival after curative resection for esophageal squamous cell carcinoma. Background: The relation between postoperative complications and long-term survival after curative surgery for esophageal squamous cell carcinoma is controversial; thus, this issue should be resolved with a large-scale, well-designed study. Methods: Clinicopathological features and survival of 580 consecutive patients who received curative resection for esophageal squamous cell carcinoma were investigated according to the development of postoperative pulmonary complications and anastomotic leakage. Results: The 5-year survival rates of patients with pStage 0, I, and II disease with postoperative complications (n = 116) were significantly poorer than those of patients without postoperative complications (n = 288) (overall 69.6% vs 46.9%, P < 0.0001; disease-specific; 76.7% vs 58.9%, P < 0.0022), whereas no differences were found in patients with pStage III and IV disease (n = 176). In the univariate and multivariate analyses for disease-specific survival, pT3, pT4, pN positivity, and development of postoperative complications were significant prognostic factors in all patients. Also, when the analysis was limited to the pStage 0, I, and II patients, development of postoperative complications, and pT3, pT4, and pN positivity, were found to be independent poor prognostic factors in multivariate analyses (hazard ratio: 1.56, 95% confidence interval, 1.01–2.41, P = 0.0476). Conclusions: The development of postoperative complications is an independent disease-specific poor prognostic factor after curative resection for patients with less-advanced esophageal squamous cell carcinoma.OBJECTIVE The objective of this study was to elucidate the impact of postoperative complications on long-term survival after curative resection for esophageal squamous cell carcinoma. BACKGROUND The relation between postoperative complications and long-term survival after curative surgery for esophageal squamous cell carcinoma is controversial; thus, this issue should be resolved with a large-scale, well-designed study. METHODS Clinicopathological features and survival of 580 consecutive patients who received curative resection for esophageal squamous cell carcinoma were investigated according to the development of postoperative pulmonary complications and anastomotic leakage. RESULTS The 5-year survival rates of patients with pStage 0, I, and II disease with postoperative complications (n = 116) were significantly poorer than those of patients without postoperative complications (n = 288) (overall 69.6% vs 46.9%, P < 0.0001; disease-specific; 76.7% vs 58.9%, P = 0.0022), whereas no differences were found in patients with pStage III and IV disease (n = 176). In the univariate and multivariate analyses for disease-specific survival, pT3, pT4, pN positivity, and development of postoperative complications were significant prognostic factors in all patients. Also, when the analysis was limited to the pStage 0, I, and II patients, development of postoperative complications, and pT3, pT4, and pN positivity, were found to be independent poor prognostic factors in multivariate analyses (hazard ratio: 1.56, 95% confidence interval, 1.01-2.41, P = 0.0476). CONCLUSIONS The development of postoperative complications is an independent disease-specific poor prognostic factor after curative resection for patients with less-advanced esophageal squamous cell carcinoma.


Oncotarget | 2016

Fibroblast growth factor receptor 2 expression, but not its genetic amplification, is associated with tumor growth and worse survival in esophagogastric junction adenocarcinoma

Ryuma Tokunaga; Yu Imamura; Kenichi Nakamura; Takatsugu Ishimoto; Shigeki Nakagawa; Keisuke Miyake; Yu Nakaji; Yasuo Tsuda; Masaaki Iwatsuki; Yoshifumi Baba; Yasuo Sakamoto; Yuji Miyamoto; Hiroshi Saeki; Naoya Yoshida; Eiji Oki; Masayuki Watanabe; Yoshinao Oda; Adam J. Bass; Yoshihiko Maehara; Hideo Baba

Background Fibroblast growth factor receptor 2 (FGFR2) genetic alterations lead to tumor cell proliferation in various types of cancer. We hypothesized that FGFR2 amplification is associated with FGFR2 expression, resulting in tumor growth and poorer outcome in esophagogastric junction (EGJ) adenocarcinoma. Patients and Methods A total of 176 consecutive chemo-naive patients with EGJ adenocarcinoma were enrolled from two academic institutions. FGFR2 amplification was examined by real-time PCR (N = 140) and FGFR2 expression with immunohistochemical staining (N = 176), and compared against clinicopathological factors and patient outcomes. The effects of FGFR2 inhibition or overexpression on cell proliferation, cell cycle, and apoptosis assays were investigated in EGJ adenocarcinoma cell lines. Downstream FGFR2, AKT and ERK were also examined. Results Based on the correlation between FGFR2 levels and FGFR2 overexpression in vitro, FGFR2 amplification was defined as copy number > 3.0. In clinical samples, FGFR2 amplification and FGFR2 IHC expression were 15% and 61%, respectively. Although these two statuses were significantly correlated (P < 0.05), only FGFR2 IHC expression was significantly associated with tumor depth (multivariate P < 0.001) and overall survival of patients (univariate P = 0.007). Supporting these findings, FGFR2 overexpression was associated with tumor cell proliferation, cell cycle progression, and anti-apoptosis. Selective inhibition of FGFR2 sufficiently suppressed tumor cell proliferation through de-phosphorylation of AKT and ERK. Conclusions FGFR2 amplification was significantly associated with FGFR2 expression. FGFR2 expression (but not FGFR2 amplification) was associated with tumor growth and patient outcomes. Our findings support FGFR2 as a novel therapeutic target for EGJ adenocarcinoma.


Annals of Surgery | 2017

Clinicopathological Features of Cervical Esophageal Cancer: Retrospective Analysis of 63 Consecutive Patients Who Underwent Surgical Resection

Hiroshi Saeki; Satoshi Tsutsumi; Takafumi Yukaya; Hirotada Tajiri; Ryosuke Tsutsumi; Sho Nishimura; Yu Nakaji; Kensuke Kudou; Shingo Akiyama; Yuta Kasagi; Yuichiro Nakashima; Masahiko Sugiyama; Hideto Sonoda; Kippei Ohgaki; Eiji Oki; Ryuji Yasumatsu; Torahiko Nakashima; Masaru Morita; Yoshihiko Maehara

Objective: The objectives of this retrospective study were to elucidate the clinicopathological features and recent surgical results of cervical esophageal cancer. Summary Background Data: Cervical esophageal cancer has been reported to have a dismal prognosis. Accurate knowledge of the clinical characteristics of cervical esophageal cancer is warranted to establish appropriate therapeutic strategies. Methods: The clinicopathological features and treatment results of 63 consecutive patients with cervical esophageal cancer (Ce group) who underwent surgical resection from 1980 to 2013 were analyzed and compared with 977 patients with thoracic or abdominal esophageal cancer (T/A group) who underwent surgical resection during that time. Results: Among the patients who received curative resection, the 5-year overall and disease-specific survival rates of the Ce patients were significantly better than those of the T/A patients (overall: 77.3% vs 46.5%, respectively, P = 0.0067; disease-specific: 81.9% vs 55.8%, respectively, P = 0.0135). Although total pharyngo-laryngo-esophagectomy procedures were less frequently performed in the recent period, the rate of curative surgical procedures was markedly higher in the recent period (2000–1013) than that in the early period (1980–1999) (44.4% vs 88.9%, P = 0.0001). The 5-year overall survival rate in the recent period (71.5%) was significantly better than that in the early period (40.7%, P = 0.0342). Conclusions: Curative resection for cervical esophageal cancer contributes to favorable outcomes compared with other esophageal cancers. Recent surgical results for cervical esophageal cancer have improved, and include an increased rate of curative resection and decreased rate of extensive surgery.


Oncology | 2017

Protein Expression of Programmed Death 1 Ligand 1 and HER2 in Gastric Carcinoma

Eiji Oki; Shinji Okano; Hiroshi Saeki; Yuichiro Umemoto; Koji Teraishi; Yu Nakaji; Koji Ando; Yoko Zaitsu; Nami Yamashita; Masahiko Sugiyama; Yuichiro Nakashima; Kippei Ohgaki; Yoshinao Oda; Yoshihiko Maehara

Objectives: Programmed death 1 (PD-1) is an immunoinhibitory receptor and has been identified as a new target for immunotherapy in cancer. Here we report the expression of PD-1 ligand 1 (PD-L1) in surgically resected gastric cancer. Materials and Methods: We examined formalin-fixed tumor samples from 144 gastric cancer patients with a primary diagnosis of gastric carcinoma. Immunohistochemistry was used to detect PD-L1. Human epidermal growth factor receptor 2 (HER2) expression and phosphatase and tensin homolog (PTEN) loss of heterozygosity were investigated in these patients. RNA interference was used to downregulate HER2 expression, and PD-L1 protein expression was assessed by flow cytometry using the gastric cancer cell line MKN45. Results: Overexpression of PD-L1 was significantly correlated with tumor invasion (p = 0.011) and associated with poor survival. The number of PD-L1-positive cases increased according to the HER2 score in clinical samples. siRNA-mediated downregulation of HER2 significantly decreased PD-L1 protein expression in MKN45 cells. Conclusions: PD-L1 expression was associated with poor survival of gastric cancer, and HER2 signaling affects the expression of PD-L1 in gastric cancer. In gastric cancer, PTEN and HER2 are potential candidate biomarkers for developing human antibodies that block PD-L1.


Surgical Case Reports | 2016

Development of fistula between esophagogastric anastomotic site and cartilage portion of trachea after subtotal esophagectomy for cervical esophageal cancer: a case report

Daisuke Taniguchi; Hiroshi Saeki; Yuichiro Nakashima; Ryosuke Tsutsumi; Sho Nishimura; Kensuke Kudou; Yu Nakaji; Hirotada Tajiri; Satoshi Tsutsumi; Takafumi Yukaya; Ryota Nakanishi; Masahiko Sugiyama; Hideto Sonoda; Kippei Ohgaki; Eiji Oki; Yoshihiko Maehara

A 65-year-old man with cT3N2M0 stage III cervical esophageal cancer underwent subtotal esophagectomy and gastric tube reconstruction through the retrosternal route after neoadjuvant chemoradiotherapy. The anastomosis was located adjacent to the left side of the trachea, and a circular stapler was used for anastomosis. Postoperative anastomotic leakage occurred, and an esophagotracheal fistula between the esophagogastric anastomotic site and cartilage portion of the trachea was observed on postoperative day 44. The patient underwent division of the fistula, direct suturing of the anastomotic leakage site, left pectoralis major muscle flap placement, and tracheotomy. He was discharged home on postoperative day 120 on an oral diet. All previous reports of tracheobronchial fistula describe the occurrence of the fistula at the membranous portion of the trachea. The formation of a fistula between the esophagogastric anastomotic site and cartilage portion of the trachea is considered a possible complication when a high esophagogastric anastomosis is created.


Cancer Science | 2016

High expression of the Notch ligand Jagged-1 is associated with poor prognosis after surgery for colorectal cancer

Masakazu Sugiyama; Eiji Oki; Yu Nakaji; Satoshi Tsutsumi; Naomi Ono; Ryota Nakanishi; Masahiko Sugiyama; Yuichiro Nakashima; Hideto Sonoda; Kippei Ohgaki; Nami Yamashita; Hiroshi Saeki; Shinji Okano; Hiroyuki Kitao; Masaru Morita; Yoshinao Oda; Yoshihiko Maehara

The importance of Notch signaling in colorectal cancer (CRC) carcinogenesis and progression has previously been presented. Increased expression of Jagged‐1 (JAG1), a Notch ligand, in CRC has been revealed, but the detailed prognostic significance of JAG1 in CRC has not been determined. Protein expression of JAG1 was examined using immunohistochemistry in 158 CRC specimens. Expression of JAG1 and E‐cadherin and their associations with clinicopathologic characteristics, overall survival (OS) and relapse‐free survival (RFS) were evaluated. In vitro studies using compounds to regulate intracellular signaling and small interfering RNA to silence JAG1 were performed in a colon cancer cell line. JAG1 expression in cancerous tissues was weak, moderate or strong in 32%, 36% and 32% of specimens, respectively, and correlated with histologic type and T stage. In multivariate analysis, JAG1 expression, histologic type and lymphatic invasion independently correlated with OS and RFS. The combination of high JAG1 expression and low E‐cadherin expression had an additive effect toward poorer OS and RFS compared with the low JAG1/high E‐cadherin expression subtype. A significant correlation between JAG1 expression and KRAS status was detected in groups stratified as high E‐cadherin expression. In vitro studies suggested that RAS‐MEK‐MAP kinase and the Wnt pathways positively regulated JAG1 expression. Gene silencing with siJAG1 indicated that JAG1 promotes the transition from epithelial to mesenchymal characteristics and cell growth. High expression of JAG1 is regulated by various pathways and is associated with poor prognosis through promoting the epithelial to mesenchymal transition and cell proliferation or maintaining cell survival in CRC.


International Journal of Cancer | 2018

Clinical significance of programmed cell death-ligand 1 expression and the immune microenvironment at the invasive front of colorectal cancers with high microsatellite instability

Shotaro Korehisa; Eiji Oki; Makoto Iimori; Yu Nakaji; Mototsugu Shimokawa; Hiroshi Saeki; Shinji Okano; Yoshinao Oda; Yoshihiko Maehara

Immunotherapy is reportedly effective in colorectal cancers (CRCs) with high microsatellite instability (MSI‐H); however, the specific cell types that respond to immune checkpoint therapy are unclear. Herein, we aimed to examine the expression of programmed cell death‐ligand 1 (PD‐L1) and related proteins in MSI‐H and microsatellite‐stable (MSS) CRCs to investigate the immune microenvironment at the tumors invasive front. The MSI status was retrospectively assessed in 499 patients undergoing surgical resection of primary CRC; of these, 48 were classified as MSI‐H. Propensity score matching was performed, and tissues from 36 and 37 patients with MSI‐H and MSS CRCs, respectively, were immunohistochemically evaluated for PD‐L1, PD‐1, CD8 and CD68. PD‐L1 expression was evaluated separately for tumor cells (PD‐L1 [T]) and tumor‐infiltrating myeloid cells in the stroma (PD‐L1 [I]). PD‐L1 (T) was positive in only 5.4% and 36.1% of MSS and MSI‐H CRCs, while PD‐L1 (I) was positive in 27% and 72.2% of these CRCs, respectively. The PD‐L1 (T) and PD‐L1 (I) expression levels in MSI‐H CRCs significantly correlated with poor differentiation, lymphatic invasion and vascular invasion (p < 0.05), and with early‐stage adenocarcinoma and high budding grade (p < 0.05), respectively. Significantly more PD‐L1 (I), CD8‐positive cells and CD68‐positive macrophages were present at the invasive front than in the central tumor in MSI‐H CRCs (p < 0.005). PD‐L1 was expressed on both tumor cells and CD68/CD163‐positive (M2) macrophages at the invasive front of MSI‐H CRCs. In conclusion, PD‐L1‐positive tumor cells and M2‐type tumor‐associated macrophages may contribute to tumor invasion and immune escape at the invasive front.


Cancer Medicine | 2017

High ubiquitin-specific protease 44 expression induces DNA aneuploidy and provides independent prognostic information in gastric cancer

Sho Nishimura; Eiji Oki; Koji Ando; Makoto Iimori; Yu Nakaji; Yuichiro Nakashima; Hiroshi Saeki; Yoshinao Oda; Yoshihiko Maehara

Chromosomal instability (CIN), characterized by aneuploidy, is a major molecular subtype of gastric cancer. The deubiquitinase USP44 is an important regulator of APC activation in the spindle checkpoint and leads to proper chromosome separation to prevent aneuploidy. Aberrant expression of USP44 leads CIN in cells; however, the correlation between USP44 and DNA aneuploidy in gastric cancer is largely unknown. We analyzed USP44 expression in 207 patients with gastric cancer by immunohistochemistry and found that the proportion of USP44 expression was higher in gastric cancer tumors (mean, 39.6%) than in gastric normal mucosa (mean, 14.6%) (P < 0.0001). DNA aneuploidy was observed in 124 gastric cancer cases and high USP44 expression in cancer strongly correlated with DNA aneuploidy (P = 0.0005). The overall survival was significantly poorer in the high USP44 expression group compared with the low USP44 group (P = 0.033). Notably, USP44 expression had no prognostic impact in the diploid subgroup; however, high USP44 expression was a strong poor prognostic factor for progression‐free survival (P = 0.018) and overall survival (P = 0.036) in the aneuploid subgroup. We also confirmed that stable overexpression of USP44 induced somatic copy‐number aberrations in hTERT‐RPE‐1 cells (50.6%) in comparison with controls (6.6%) (P < 0.0001). Collectively, our data show USP44 has clinical impact on the induction of DNA aneuploidy and poor prognosis in the CIN gastric cancer subtype.


Surgical Case Reports | 2018

Correction to: Recurrence with pagetoid spread arising 17 years after surgery for intramucosal rectal cancer: a case report

Taichi Matsubara; Yuta Kasagi; Kippei Ogaki; Yu Nakaji; Ryota Nakanishi; Yuichiro Nakashima; Masahiko Sugiyama; Hideto Sonoda; Hiroshi Saeki; Eiji Oki; Yoshihiko Maehara

After publication of the original article [1] the authors noted that the following errors had occurred:


Surgical Case Reports | 2017

Successful surgical intervention for rectal perforation due to polyarteritis nodosa: report of a case

Keiji Yoshiya; Yu Imamura; Yu Nakaji; Daisuke Taniguchi; Rinne Takeda; Koji Ando; Yuichiro Nakashima; Motohiro Shimizu; Kippei Ohgaki; Norihiro Furusyo; Takuya Matsumoto; Hiroshi Saeki; Yoshinao Oda; Eiji Oki; Yoshihiko Maehara

BackgroundPolyarteritis nodosa (PAN) is a primary systemic necrotizing vasculitis with diffuse organ involvements, resulting in a high mortality rate due to multiple organ failure. Although the small bowel is the frequently targeted organ of PAN-associated vasculitis, rectal involvement is very rare, and only one case of rectal bleeding has been previously reported. The mortality rate of PAN with gastrointestinal (GI) perforation is reportedly much higher than that of without severe GI involvement. We herein report the first case of rectal perforation due to PAN, successfully managed with an adequate surgical intervention.Case presentationA 66-year-old woman with PAN had abdominal pain and melena with guarding. Computed tomography scan showed abdominal free air and bubbles in the rectal hematoma. We diagnosed it acute peritonitis, and emergency surgery was performed. After removing rectal hematoma and necrotic tissue, a huge lack of rectal wall spreading to the pelvirectal space was observed. In order to totally remove the necrotic tissue, abdominoperineal resection was needed. Together with histopathological examinations which showed neutrophils and fibrinous necrosis, we finally diagnosed rectal perforation due to PAN. At 19-month follow-up after surgery, she was still healthy with a stable disease of PAN.ConclusionsWe herein reported the first case of successfully managed rectal perforation due to PAN. Early adequate surgical resection may be important for the case with rectal perforation.

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