International Institute of Anticancer Research Acta Medica Okayama 0250-7005 44 6 2024 Senescent Fibroblasts Potentiate Peritoneal Metastasis of Diffuse-type Gastric Cancer Cells via IL-8–mediated Crosstalk 2497 2509 EN YUNCHENG LI Departments of Gastroenterological Surgery and Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences HIROSHI TAZAWA Departments of Gastroenterological Surgery and Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences YASUO NAGAI Departments of Gastroenterological Surgery and Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences SHUTO FUJITA Departments of Gastroenterological Surgery and Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences TOMOHIRO OKURA Departments of Gastroenterological Surgery and Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences RYOHEI SHOJI Departments of Gastroenterological Surgery and Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences MOTOHIKO YAMADA Departments of Gastroenterological Surgery and Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences SATORU KIKUCHI Departments of Gastroenterological Surgery and Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences SHINJI KURODA Departments of Gastroenterological Surgery and Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences TOSHIAKI OHARA Departments of Gastroenterological Surgery and Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences KAZUHIRO NOMA Departments of Gastroenterological Surgery and Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences MASAHIKO NISHIZAKI Departments of Gastroenterological Surgery and Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences SHUNSUKE KAGAWA Departments of Gastroenterological Surgery and Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences TOSHIYOSHI FUJIWARA Departments of Gastroenterological Surgery and Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Background/Aim: Diffuse-type gastric cancer (DGC) often forms peritoneal metastases, leading to poor prognosis. However, the underlying mechanism of DGC-mediated peritoneal metastasis is poorly understood. DGC is characterized by desmoplastic stroma, in which heterogeneous cancer-associated fibroblasts (CAFs), including myofibroblastic CAFs (myCAFs) and senescent CAFs (sCAFs), play a crucial role during tumor progression. This study investigated the CAF subtypes induced by GC cells and the role of sCAFs in peritoneal metastasis of DGC cells. Materials and Methods: Conditioned medium of human DGC cells (KATOIII, NUGC-4) and human intestinal-type GC (IGC) cells (MKN-7, N87) was used to induce CAFs. CAF subtypes were evaluated by analyzing the expression of α–smooth muscle actin (α-SMA), senescence-associated β-galactosidase (SA-β-gal), and p16 in human normal fibroblasts (GF, FEF-3). A cytokine array was used to explore the underlying mechanism of GC-induced CAF subtype development. The role of sCAFs in peritoneal metastasis of DGC cells was analyzed using a peritoneally metastatic DGC tumor model. The relationships between GC subtypes and CAF-related markers were evaluated using publicly available datasets. Results: IGC cells significantly induced α-SMA+ myCAFs by secreting transforming growth factor–β, whereas DGC cells induced SA-β-gal+/p16+ sCAFs by secreting interleukin (IL)-8. sCAFs further secreted IL-8 to promote DGC cell migration. In vivo experiments demonstrated that co-inoculation of sCAFs significantly enhanced peritoneal metastasis of NUGC-4 cells, which was attenuated by administration of the IL-8 receptor antagonist navarixin. p16 and IL-8 expression was significantly associated with poor prognosis of DGC patients. Conclusion: sCAFs promote peritoneal metastasis of DGC via IL-8–mediated crosstalk. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 1435-2443 407 2 2022 Surgical technique of suprapancreatic D2 lymphadenectomy focusing on the posterior hepatic plexus for advanced gastric cancer 871 877 EN Nobuhiko Kanaya Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Shinji Kuroda Department of Gastroenterological Surgery, Dentistry and Pharmaceutical Sciences, Okayama University Graduate School of Medicine Yoshihiko Kakiuchi Department of Gastroenterological Surgery, Dentistry and Pharmaceutical Sciences, Okayama University Graduate School of Medicine Sho Takeda Department of Gastroenterological Surgery, Dentistry and Pharmaceutical Sciences, Okayama University Graduate School of Medicine Satoru Kikuchi Department of Gastroenterological Surgery, Dentistry and Pharmaceutical Sciences, Okayama University Graduate School of Medicine Kazuhiro Noma Department of Gastroenterological Surgery, Dentistry and Pharmaceutical Sciences, Okayama University Graduate School of Medicine Ryuichi Yoshida Department of Gastroenterological Surgery, Dentistry and Pharmaceutical Sciences, Okayama University Graduate School of Medicine Yuzo Umeda Department of Gastroenterological Surgery, Dentistry and Pharmaceutical Sciences, Okayama University Graduate School of Medicine Fuminori Teraishi Department of Gastroenterological Surgery, Dentistry and Pharmaceutical Sciences, Okayama University Graduate School of Medicine Masahiko Nishizaki Department of Gastroenterological Surgery, Dentistry and Pharmaceutical Sciences, Okayama University Graduate School of Medicine Shunsuke Kagawa Department of Gastroenterological Surgery, Dentistry and Pharmaceutical Sciences, Okayama University Graduate School of Medicine Toshiyoshi Fujiwara Department of Gastroenterological Surgery, Dentistry and Pharmaceutical Sciences, Okayama University Graduate School of Medicine Purpose Although D2 lymphadenectomy is currently considered a standard procedure for advanced gastric cancer (GC) worldwide, there is room for discussion about the appropriate range of suprapancreatic D2 lymphadenectomy. Focusing on the posterior hepatic plexus (PHP), which is not well recognized, we developed a surgical technique of suprapancreatic D2 lymphadenectomy, which we have called PHP-D2, and its short-term and long-term efficacies were evaluated in comparison with non-PHP-D2. Methods GC patients who underwent distal gastrectomy with D2 lymphadenectomy between July 2006 and May 2013 were enrolled, from which patients who had peritoneal metastasis and/or were peritoneal cytology-positive during surgery were excluded. Their medical records were retrospectively reviewed. Results Ninety-two patients (non-PHP-D2: 48, PHP-D2: 44) were enrolled. Shorter operation time (330 min vs 275 min, p < 0.0001) and less blood loss (290 mL vs 125 mL, p < 0.0001) were observed in PHP-D2, and no pancreatic fistulas were observed in PHP-D2. More lymph nodes of #11p (1 vs 1.5, p = 0.0328) and #12a lymph nodes (0 vs 1, p = 0.0034) were retrieved in PHP-D2, with no significant differences in #8a and #9 lymph nodes. Lymphatic recurrence was significantly less in PHP-D2 (p = 0.0166), and univariate and multivariate analyses showed that non-PHP-D2 was a significant risk factor for lymphatic recurrence (p = 0.0158), although there were no significant differences between non-PHP-D2 and PHP-D2 in 5-year overall survival and 5-year relapse-free survival. Conclusion PHP-D2 was a safe and feasible procedure that had the potential to reduce lymphatic recurrence, and it can be a standard procedure of D2 lymphadenectomy for advanced GC. No potential conflict of interest relevant to this article was reported.

The American Society of Gene and Cell Therapy Acta Medica Okayama 15250016 29 10 2021 Local oncolytic adenovirotherapy produces an abscopal effect via tumor-derived extracellular vesicles 2920 2930 EN Yoshihiko Kakiuchi Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Shinji Kuroda Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Nobuhiko Kanaya Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Kento Kumon Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Tomoko Tsumura Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Masashi Hashimoto Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Chiaki Yagi Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Ryoma Sugimoto Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Yuki Hamada Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Satoru Kikuchi Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Masahiko Nishizaki Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Shunsuke Kagawa Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Hiroshi Tazawa Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Yasuo Urata Oncolys BioPharma, Inc Toshiyoshi Fujiwara Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Extracellular vesicles (EVs) play important roles in various intercellular communication processes. The abscopal effect is an interesting phenomenon in cancer treatment, in which immune activation is generally considered a main factor. We previously developed a telomerase-specific oncolytic adenovirus, Telomelysin (OBP-301), and occasionally observed therapeutic effects on distal tumors after local treatment in immunodeficient mice. In this study, we hypothesized that EVs may be involved in the abscopal effect of OBP-301. EVs isolated from the supernatant of HCT116 human colon carcinoma cells treated with OBP-301 were confirmed to contain OBP-301, and they showed cytotoxic activity (apoptosis and autophagy) similar to OBP-301. In bilateral subcutaneous HCT116 and CT26 tumor models, intratumoral administration of OBP-301 produced potent antitumor effects on tumors that were not directly treated with OBP-301, involving direct mediation by tumor-derived EVs containing OBP-301. This indicates that immune activation is not the main factor in this abscopal effect. Moreover, tumor-derived EVs exhibited high tumor tropism in orthotopic HCT116 rectal tumors, in which adenovirus E1A and adenovirus type 5 proteins were observed in metastatic liver tumors after localized rectal tumor treatment. In conclusion, local treatment with OBP-301 has the potential to produce abscopal effects via tumor-derived EVs. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 1743-9191 89 2021 Efficacy and safety of short-term (3 days) enoxaparin in preventing venous thromboembolism after gastric cancer surgery: A single-center, prospective cohort study 105946 EN Shinji Kuroda Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Satoru Kikuchi Okayama University Hospital Yoshihiko Kakiuchi Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Megumi Watanabe Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Kazuya Kuwada Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Tomoko Tsumura Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Masahiko Nishizaki Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Shunsuke Kagawa Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Shiro Hinotsu Department of Biostatistics and Data Management, Sapporo Medical University School of Medicine Toshiyoshi Fujiwara Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Background: Pharmacologic prophylaxis such as enoxaparin for venous thromboembolism (VTE) is rarely used in Japan, even following abdominal cancer surgery, for which it is recommended in relevant guidelines (at least 7 days of use) along with mechanical prophylaxis with intermittent pneumatic compression. Reasons for enoxaparin’s unpopularity include concerns over postoperative bleeding and its inconvenience in clinical practice. Here, we conducted a prospective clinical study of short-term (3 days) use of enoxaparin, which is considered to minimally impact postoperative management without increasing bleeding risk. Methods: Gastric cancer patients who underwent gastrectomy received enoxaparin for 3 days from postoperative day (POD) 1 to 4. The primary endpoint was the incidence of deep vein thrombosis (DVT), which was examined primarily via Doppler ultrasonography of the lower limbs between POD 8 and 14. The planned sample size was 70, which was calculated based on an estimated incidence rate of 9% and an upper limit of incidence rate of 20%, with alpha of 0.05 and beta of 0.2. Results: A total of 70 gastric cancer patients were enrolled, and ultimately, 68 patients received the protocol intervention and DVT evaluation. Sixty-seven patients completed 6 enoxaparin injections, but 1 patient did not complete the course due to abdominal bleeding after initiation. The incidence of DVT was 4.4% (3/68), and the 95% upper confidence interval was 12.2%, lower than the 20% threshold we set as the upper limit of DVT incidence. DVT was detected only in the peripheral veins of the lower extremities in all 3 affected patients. The incidence of bleeding-related complications, which were not severe, was 1.5% (1/68). Conclusions: Short-term (3 days) use of enoxaparin was shown to be effective and safe for VTE prophylaxis, comparable to regular use (at least 7 days), in postoperative management of gastric cancer surgery. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 0941-1291 51 2021 Accreditation as a qualified surgeon improves surgical outcomes in laparoscopic distal gastrectomy 1978 1984 EN Satoru Kikuchi Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Tetsuya Kagawa Department of Gastroenterological Surgery, Shikoku Cancer Center Shinji Kuroda Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Masahiko Nishizaki Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Nobuo Takata Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Kazuya Kuwada Department of Surgery, Okayama Red Cross Hospital Ryohei Shoji Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Yoshihiko Kakiuchi Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Toshiharu Mitsuhashi Center for Innovative Clinical Medicine, Okayama University Hospital Yuzo Umeda Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Kazuhiro Noma Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Shunsuke Kagawa Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Toshiyoshi Fujiwara Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Purpose: The Endoscopic Surgical Skill Quantification System for qualified surgeons (QSs) was introduced in Japan to improve surgical outcomes. This study reviewed the surgical outcomes after initial experience performing laparoscopic distal gastrectomy (LDG) and evaluated the improvement in surgical outcomes following accreditation as a QS. Methods: Eighty-seven consecutive patients who underwent LDG for gastric cancer by a single surgeon were enrolled in this study. The cumulative sum method was used to analyze the learning curve for LDG. The surgical outcomes were evaluated according to the two phases of the learning curve (learning period vs. mastery period) and accreditation (non-QS period vs. QS period). Results: The learning period for LDG was 48 cases. Accreditation was approved at the 67th case. The operation time and estimated blood loss were significantly reduced in the QS period compared to the non-QS period (230 vs. 270 min, p<0.001; 20.5 vs. 59.8 ml, p=0.024, respectively). Furthermore, the major complication rate was significantly lower in the QS period than in the non-QS period (0 vs. 10.6%, p=0.044). Conclusions: Experience performing approximately 50 cases is required to reach proficiency in LDG. After receiving accreditation as a QS, the surgical outcomes, including the complication rate, were improved. No potential conflict of interest relevant to this article was reported.

Springer Acta Medica Okayama 2198-7793 7 1 2021 Long-term survival without recurrence after surgery for gastric yolk sac tumor-like carcinoma: a case report 111 EN Hibiki Umeda Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences Satoru Kikuchi Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences Shinji Kuroda Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences Shuya Yano Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences Takehiro Tanaka Department of Pathology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Kazuhiro Noma Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences Masahiko Nishizaki Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences Shunsuke Kagawa Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences Yuzo Umeda Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences Toshiyoshi Fujiwara Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences Background Gastric yolk sac tumor (YST)-like carcinoma is extremely rare, and its prognosis is poor, because most patients have widespread metastases at the time of diagnosis. We report a case of gastric YST-like carcinoma with an adenocarcinoma component without metastases in which curative resection was performed. Case presentation A 77-year-old man complaining of melena and dizziness due to anemia was diagnosed with poorly differentiated adenocarcinoma in the gastric cardia, with a benign ulcer in the gastric body. He underwent total gastrectomy with D2 lymph node dissection for the tumor. Histological examination of the resected specimens revealed a mixture of reticular and glandular neoplastic components morphologically. In the reticular area, an endodermal sinus pattern and some Schiller-Duval bodies were confirmed. Gastric YST-like carcinoma with adenocarcinoma components, T2N0M0 Stage IB, was diagnosed. Immunohistochemical analysis showed that the YST was positive for carcinoembryonic antigen (CEA), alpha-fetoprotein (AFP) and p53. In contrast, the adenocarcinoma was positive for p53 and negative for CEA and AFP. The patient remained healthy as of 7 years postoperatively, with no recurrence. Conclusions Routine medical examinations or endoscopic examinations for accidental symptom may be helpful for early diagnosis and good prognosis for gastric YST-like carcinoma, although the prognosis is generally poor. No potential conflict of interest relevant to this article was reported.

Okayama University Medical School Acta Medica Okayama 0386-300X 75 2 2021 Long-term Survival with a Rare Advanced Primary Gastrointestinal Malignant Melanoma Treated with Laparoscopic Surgery/Immune Checkpoint Inhibitor 231 238 EN Motochika Endo Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Shuya Yano Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Hiroaki Asano Department of Surgery, Mitoyo general Hospital Sho Takeda Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Yuki Hamada Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Yoshitaka Kondo Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Shinji Kuroda Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Kunitoshi Shigeyasu Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Satoru Kikuchi Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Takehiro Tanaka Department of Pathology, Okayama University Hospital Fuminori Teraishi Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Masahiko Nishizaki Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Shunsuke Kagawa Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Toshiyoshi Fujiwara Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Case Report 10.18926/AMO/61906 Targeted therapies for malignant melanoma have improved patients’ prognoses. A primary gastrointestinal malignant melanoma is very rare, with no standard treatment strategy. We treated a 78-year-old Japanese female with advanced primary gastrointestinal melanoma of the descending colon and gallbladder. We administered a multidisciplinary treatment: surgical resection of the descending colon and gallbladder tumors, resection of the metastatic lymph nodes behind the pancreas head, and immune checkpoint antibody-blockade therapy (nivolumab) for ~4 years. PET/CT demonstrated no recurrent lesion for > 3 years. Multidisciplinary therapies (e.g., surgery, chemotherapy, radiotherapy, target therapy, and immune checkpoint antibody-blockade therapy) can successfully treat primary gastrointestinal malignant melanoma. No potential conflict of interest relevant to this article was reported.

Public Library of Science Acta Medica Okayama 1932-6203 15 11 2020 Short-term and long-term comparisons of laparoscopy-assisted proximal gastrectomy with esophagogastrostomy by the double-flap technique and laparoscopy-assisted total gastrectomy for proximal gastric cancer e0242223 EN Tomoko Tsumura Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Shinji Kuroda Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Masahiko Nishizaki Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Satoru Kikuchi Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Yoshihiko Kakiuchi Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Nobuo Takata Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Atene Ito Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Megumi Watanabe Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Kazuya Kuwada Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Shunsuke Kagawa Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Toshiyoshi Fujiwara Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Background Although proximal gastrectomy (PG) is a recognized surgical procedure for early proximal gastric cancer, total gastrectomy (TG) is sometimes selected due to concern about severe gastroesophageal reflux. Esophagogastrostomy by the double-flap technique (DFT) is an anti-reflux reconstruction after PG, and its short-term effectiveness has been reported. However, little is known about the long-term effects on nutritional status and quality of life (QOL). Methods Gastric cancer patients who underwent laparoscopy-assisted PG (LAPG) with DFT or laparoscopy-assisted TG (LATG) between April 2011 and March 2014 were retrospectively analyzed. Body weight (BW), body mass index (BMI), and prognostic nutritional index (PNI) were reviewed to assess nutritional status, and the Postgastrectomy Syndrome Assessment Scale (PGSAS)-45 was used to assess QOL. Results A total of 36 patients (LATG: 17, LAPG: 19) were enrolled. Four of 17 LATG patients (24%) were diagnosed with Stage ≥II after surgery, and half received S-1 adjuvant chemotherapy. BW and PNI were better maintained in LAPG than in LATG patients until 1-year follow-up. Seven of 16 LATG patients (44%) were categorized as “underweight (BMI<18.5 kg/m2)” at 1-year follow-up, compared to three of 18 LAPG patients (17%; p = 0.0836). The PGSAS-45 showed no significant difference in all QOL categories except for decreased BW (p = 0.0132). Multivariate analysis showed that LATG was the only potential risk factor for severe BW loss (odds ratio: 3.03, p = 0.0722). Conclusions LAPG with DFT was superior to LATG in postoperative nutritional maintenance, and can be the first option for early proximal gastric cancer. No potential conflict of interest relevant to this article was reported.

Wiley Acta Medica Okayama 1758-5902 2021 14 2020 Intracorporeal semi‐hand‐sewn Billroth I reconstruction in total laparoscopic distal gastrectomy 640 643 EN Satoru Kikuchi Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Shinji Kuroda Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Masahiko Nishizaki Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Kazuya Kuwada Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Nobuo Takata Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Yoshihiko Kakiuchi Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Shuya Yano Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Kazuhiro Noma Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Shunsuke Kagawa Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Toshiyoshi Fujiwara Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Introduction Intracorporeal Billroth I (B‐I) reconstruction using an endoscopic linear stapler (ELS) is widely performed in total laparoscopic distal gastrectomy. However, conventional procedures require many ELSs for anastomosis. Here, we introduce the novel intracorporeal semi‐hand‐sewn (SHS) B‐I reconstruction. Materials and surgical technique After the transection of stomach and duodenum using ELS following adequate lymph node dissection, small entry holes were made on the anterior wall in the greater curvature of the stomach and the duodenal stump. The posterior walls of both the remnant stomach and the duodenum were attached with the ELS and fired to create the posterior wall of the B‐I anastomosis. All the transection line of the duodenum and one‐third of the transection line of the stomach were dissected; finally the anterior wall suturing at the anastomotic site was performed by the laparoscopic hand‐sewn technique. Discussion SHS procedure was performed for 17 gastric cancer patients. There were no intraoperative complications or conversions to open surgery. One intra‐abdominal abscess was observed although there was no anastomotic leakage. The median reconstruction time was 48 minutes (32‐63). The SHS procedure was safe, feasible, and economical, although it requires sufficient laparoscopic suturing and ligation skill. No potential conflict of interest relevant to this article was reported.

Cell Press Acta Medica Okayama 2372-7705 18 2020 Boosting Replication and Penetration of Oncolytic Adenovirus by Paclitaxel Eradicate Peritoneal Metastasis of Gastric Cancer 262 271 EN Wataru Ishikawa Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Satoru Kikuchi Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Toshihiro Ogawa Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Motoyasu Tabuchi Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Hiroshi Tazawa Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Shinji Kuroda Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Kazuhiro Noma Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Masahiko Nishizaki Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Shunsuke Kagawa Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Yasuo Urata Oncolys BioPharma, Inc. Toshiyoshi Fujiwara Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Peritoneal metastasis is the most frequent form of distant metastasis and recurrence in gastric cancer, and the prognosis is extremely poor due to the resistance of systemic chemotherapy. Here, we demonstrate that intraperitoneal (i.p.) administration of a green fluorescence protein (GFP)-expressing attenuated adenovirus with oncolytic potency (OBP-401) synergistically suppressed the peritoneal metastasis of gastric cancer in combination with paclitaxel (PTX). OBP-401 synergistically suppressed the viability of human gastric cancer cells in combination with PTX. PTX enhanced the antitumor effect of OBP-401 due to enhanced viral replication in cancer cells. The combination therapy increased induction of mitotic catastrophe, resulting in accelerated autophagy and apoptosis. Peritoneally disseminated nodules were selectively visualized as GFP-positive spots by i.p. administration of OBP-401 in an orthotopic human gastric cancer peritoneal dissemination model. PTX enhanced the deep penetration of OBP-401 into the disseminated nodules. Moreover, a non-invasive in vivo imaging system demonstrated that the combination therapy of i.p. OBP-401 administration with PTX significantly inhibited growth of peritoneal metastatic tumors and the amount of malignant ascites. i.p. virotherapy with PTX may be a promising treatment strategy for the peritoneal metastasis of gastric cancer. No potential conflict of interest relevant to this article was reported.

Cell Press Acta Medica Okayama 15250016 28 3 2020 Immune Modulation by Telomerase-Specific Oncolytic Adenovirus Synergistically Enhances Antitumor Efficacy with Anti-PD1 Antibody 794 804 EN Nobuhiko Kanaya Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Shinji Kuroda Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Yoshihiko Kakiuchi Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Kento Kumon Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Tomoko Tsumura Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Masashi Hashimoto Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Toshiaki Morihiro Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Tetsushi Kubota Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Katsuyuki Aoyama Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Satoru Kikuchi Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Masahiko Nishizaki Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Shunsuke Kagawa Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Hiroshi Tazawa Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Hiroyuki Mizuguchi Laboratory of Biochemistry and Molecular Biology, Graduate School of Pharmaceutical Sciences, Osaka University Yasuo Urata Oncolys BioPharma Toshiyoshi Fujiwara Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences The clinical benefit of monotherapy involving immune checkpoint inhibitors (ICIs) such as anti-programmed death-1 antibody (PD-1 Ab) is limited to small populations. We previously developed a telomerase-specific oncolytic adenovirus, Telomelysin (OBP-301), the safety of which was confirmed in a phase I clinical study. Here, we examined the potential of OBP-502, an OBP-301 variant, as an agent for inducing immunogenic cell death (ICD) and synergistically enhancing the efficacy of OBP-502 with PD-1 Ab using CT26 murine colon cancer and PAN02 murine pancreatic cancer cell lines. OBP-502 induced the release of ICD molecules such as adenosine triphosphate (ATP) and high-mobility group box protein 1 (HMGB1) from CT26 and PAN02 cells, leading to recruitment of CD8-positive lymphocytes and inhibition of Foxp3-positive lymphocyte infiltration into tumors. Combination therapy involving OBP-502 intratumoral administration and PD-1 Ab systemic administration significantly suppressed the growth of not only OBP-502-treated tumors but also tumors not treated with OBP-502 (so-called abscopal effect) in CT26 and PAN02 bilateral subcutaneous tumor models, in which active recruitment of CD8-positve lymphocytes was observed even in tumors not treated with OBP-502. This combined efficacy was similar to that observed in a CT26 rectal orthotopic tumor model involving liver metastases. In conclusion, telomerase-specific oncolytic adenoviruses are promising candidates for combined therapies with ICIs. No potential conflict of interest relevant to this article was reported.

Nature Publishing Group Acta Medica Okayama 2045-2322 9 2019 Visualization of epithelial-mesenchymal transition in an inflammatory microenvironment-colorectal cancer network 16378 EN Takeshi Ieda Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Hiroshi Tazawa Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Hiroki Okabayashi Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Shuya Yano Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Kunitoshi Shigeyasu Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Shinji Kuroda Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Toshiaki Ohara Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Kazuhiro Noma Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Hiroyuki Kishimoto Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Masahiko Nishizaki Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Shunsuke Kagawa Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Yasuhiro Shirakawa Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Takashi Saitou Department of Molecular Medicine for Pathogenesis, Ehime University Graduate School of Medicine Takeshi Imamura Department of Molecular Medicine for Pathogenesis, Ehime University Graduate School of Medicine Toshiyoshi Fujiwara Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Epithelial-mesenchymal transition (EMT) is a biological process by which epithelial cells acquire mesenchymal characteristics. In malignant tumors, EMT is crucial for acquisition of a mesenchymal phenotype with invasive and metastatic properties, leading to tumor progression. An inflammatory microenvironment is thought to be responsible for the development and progression of colorectal cancer (CRC); however, the precise role of inflammatory microenvironments in EMT-related CRC progression remains unclear. Here, we show the spatiotemporal visualization of CRC cells undergoing EMT using a fluorescence-guided EMT imaging system in which the mesenchymal vimentin promoter drives red fluorescent protein (RFP) expression. An inflammatory microenvironment including TNF-alpha, IL-1 beta, and cytokine-secreting inflammatory macrophages induced RFP expression in association with the EMT phenotype in CRC cells. In vivo experiments further demonstrated the distribution of RFP-positive CRC cells in rectal and metastatic tumors. Our data suggest that the EMT imaging system described here is a powerful tool for monitoring EMT in inflammatory microenvironment-CRC networks. No potential conflict of interest relevant to this article was reported.

Nature Publishing Group Acta Medica Okayama 2045-2322 9 2019 PD-L1 expression combined with microsatellite instability/CD8+tumor infiltrating lymphocytes as a useful prognostic biomarker in gastric cancer 4633 EN Toshiaki Morihiro Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Shinji Kuroda Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Nobuhiko Kanaya Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Yoshihiko Kakiuchi Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Tetsushi Kubota Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Katsuyuki Aoyama Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Takehiro Tanaka Department of Pathology, Okayama University Satoru Kikuch Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Takeshi Nagasaka Department of Clinical Oncology, Kawasaki Medical School Masahiko Nishizaki Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Shunsuke Kagawa Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Hiroshi Tazawa Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Toshiyoshi Fujiwara Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences While the importance of programmed death-ligand 1 (PD-L1), mutation burden caused by microsatellite instability (MSI), and CD8+ tumor infiltrating lymphocytes (TILs) has become evident, the significance of PD-L1 expression on prognosis still remains controversial. We evaluated the usefulness of combined markers of PD-L1 and MSI or CD8+ TILs as a prognostic biomarker in gastric cancer. A total of 283 patients with gastric cancer were reviewed retrospectively. PD-L1 expression on >5% tumor cells was defined as PD-L1-positive. PD-L1-positive rate was 15.5% (44/283). PD-L1 positivity was significantly correlated with invasive and advanced cancer and also significantly correlated with MSI, whereas no significance was observed with CD8+ TILs. Kaplan-Meier analysis showed that PD-L1 positivity significantly correlated with a poor prognosis (p = 0.0025). Multivariate analysis revealed that PD-L1 positivity was an independent poor prognostic factor (hazard ratio [HR]: 1.97, p = 0.0106) along with diffuse histological type and lymph node metastases. Combinations of PD-L1 and MSI (HR: 2.18) or CD8+ TILs (HR: 2.57) were stronger predictive factors for prognosis than PD-L1 alone. In conclusion, combined markers of PD-L1 and MSI or CD8+ TILs may be more useful prognostic biomarkers in gastric cancer, and better clarify the immune status of gastric cancer No potential conflict of interest relevant to this article was reported.

Okayama University Medical School Acta Medica Okayama 0386-300X 70 5 2016 A Phase II Clinical Trial of the Efficacy and Safety of Short-term (3 days) Enoxaparin for the Prevention of Venous Thromboembolism after Gastric Cancer Surgery 401 404 EN Shinji Kuroda Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Satoru Kikuchi Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Masahiko Nishizaki Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Shunsuke Kagawa Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Shiro Hinotsu Center for Innovative Clinical Medicine, Okayama University Hospital Toshiyoshi Fujiwara Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Clinical Study Protocols 10.18926/AMO/54601 Although intermittent pneumatic compression (IPC) has become common as perioperative prophylaxis for venous thromboembolism (VTE) consisting of pulmonary thromboembolism (PE) and deep vein thrombosis (DVT), the prophylactic effect against VTE, especially lethal PE, is not yet satisfactory. Therefore, pharmacologic prophylaxis, such as with enoxaparin, is desirable. While the efficacy and safety of enoxaparin have been proven in several clinical trials, concern about bleeding with longterm (at least 7 days) use have potentially decreased its widespread adoption. We have launched a phase II study to evaluate the efficacy and safety of short-term (3 days) enoxaparin, in which a total of 70 gastric cancer patients undergoing gastrectomy will be recruited, and the primary endpoint is the incidence of DVT. This study could contribute to making pharmacologic prophylaxis for VTE more common. No potential conflict of interest relevant to this article was reported.

Okayama University Medical School Acta Medica Okayama 0386-300X 70 3 2016 Recurrence after Endoscopic Curative Resection of Mucosal Gastric Cancer Associated with an Adjacent Neoplastic Precursor Lesion 213 216 EN Satoru Kikuchi Departments of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Shunsuke Kagawa Departments of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Toshiaki Ohara Departments of Pathology and Experimental Medicine, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Tetsushi Kubota Departments of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Kazuya Kuwada Departments of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Tetsuya Kagawa Departments of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Shinji Kuroda Departments of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Yasuhiro Shirakawa Departments of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Masahiko Nishizaki Departments of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Toshiyoshi Fujiwara Departments of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Case Report 10.18926/AMO/54421 A 69-year-old man underwent endoscopic submucosal dissection (ESD) for early gastric cancer (EGC) at the lesser curvature in the angle of stomach. Histological examination revealed tub1, pM, ly0, v0, pLM(-), pVM(-), and the resection was considered curative. The scar after ESD was followed by esophagogastroduodenoscopy (EGD) and biopsy. Twenty months later, EGD showed an ulcerative lesion in the vicinity of the ESD scar, and histological examination of the biopsy specimen showed adenocarcinoma. A distal gastrectomy with lymph node dissection was then performed. Postoperative pathology showed tub1, pM, pN0, ly0, v0, and Stage 1A. Skip lesions were seen in the specimen resected by ESD, and the histological review confirmed so-called “dysplasia-like atypia” (DLA) between the lesions. It has been reported recently that in DLA, the dysplasia-like change involves only the bases of the pits, without upper pit or surface epithelium involvement, and it is said that the rate of DLA is higher in gastric cancer patients. We speculated that a precancerous lesion close to the resected cancer developed into a local recurrence. No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 1525-0016 2014 Biological Ablation of Sentinel Lymph Node Metastasis in Submucosally Invaded Early Gastrointestinal Cancer EN Satoru Kikuchi Hiroyuki Kishimoto Hiroshi Tazawa Yuuri Hashimoto Shinji Kuroda Masahiko Nishizaki Takeshi Nagasaka Yasuhiro Shirakawa Shunsuke Kagawa Yasuo Urata Robert M Hoffman Toshiyoshi Fujiwara Currently, early gastrointestinal cancers are treated endoscopically, as long as there are no lymph node metastases. However, once a gastrointestinal cancer invades the submucosal layer, the lymph node metastatic rate rises to higher than 10%. Therefore, surgery is still the gold standard to remove regional lymph nodes containing possible metastases. Here, to avoid prophylactic surgery, we propose a less-invasive biological ablation of lymph node metastasis in submucosally invaded gastrointestinal cancer patients. We have established an orthotopic early rectal cancer xenograft model with spontaneous lymph node metastasis by implantation of green fluorescent protein (GFP)-labeled human colon cancer cells into the submucosal layer of the murine rectum. A solution containing telomerase-specific oncolytic adenovirus was injected into the peritumoral submucosal space, followed by excision of the primary rectal tumors mimicking the endoscopic submucosal dissection (ESD) technique. Seven days after treatment, GFP signals had completely disappeared indicating that sentinel lymph node metastasis was selectively eradicated. Moreover, biologically treated mice were confirmed to be relapse-free even 4 weeks after treatment. These results indicate that virus-mediated biological ablation selectively targets lymph node metastasis and provides a potential alternative to surgery for submucosal invasive gastrointestinal cancer patients. No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2014 Fluorescence virus-guided capturing system of human colorectal circulating tumour cells for non-invasive companion diagnostics EN Kunitoshi Shigeyasu Hiroshi Tazawa Yuuri Hashimoto Yoshiko Mori Masahiko Nishizaki Hiroyuki Kishimoto Takeshi Nagasaka Shinji Kuroda Yasuo Urata Ajay Goel Shunsuke Kagawa Toshiyoshi Fujiwara Background Molecular-based companion diagnostic tests are being used with increasing frequency to predict their clinical response to various drugs, particularly for molecularly targeted drugs. However, invasive procedures are typically required to obtain tissues for this analysis. Circulating tumour cells (CTCs) are novel biomarkers that can be used for the prediction of disease progression and are also important surrogate sources of cancer cells. Because current CTC detection strategies mainly depend on epithelial cell-surface markers, the presence of heterogeneous populations of CTCs with epithelial and/or mesenchymal characteristics may pose obstacles to the detection of CTCs. Methods We developed a new approach to capture live CTCs among millions of peripheral blood leukocytes using a green fluorescent protein (GFP)-expressing attenuated adenovirus, in which the telomerase promoter regulates viral replication (OBP-401, TelomeScan). Results Our biological capturing system can image epithelial and mesenchymal tumour cells with telomerase activities as GFP-positive cells. After sorting, direct sequencing or mutation-specific PCR can precisely detect different mutations in KRAS, BRAF and KIT genes in epithelial, mesenchymal or epithelial–mesenchymal transition-induced CTCs, and in clinical blood samples from patients with colorectal cancer. Conclusions This fluorescence virus-guided viable CTC capturing method provides a non-invasive alternative to tissue biopsy or surgical resection of primary tumours for companion diagnostics. No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 1078-0432 19 23 2013 A Genetically Engineered Oncolytic Adenovirus Decoys and Lethally Traps Quiescent Cancer Stem-like Cells in S/G(2)/M Phases 6495 6505 EN Shuya Yano Hiroshi Tazawa Yuuri Hashimoto Yasuhiro Shirakawa Shinji Kuroda Masahiko Nishizaki Hiroyuki Kishimoto Futoshi Uno Takeshi Nagasaka Yasuo Urata Shunsuke Kagawa Robert M. Hoffman Toshiyoshi Fujiwara Purpose: Because chemoradiotherapy selectively targets proliferating cancer cells, quiescent cancer stem-like cells are resistant. Mobilization of the cell cycle in quiescent leukemia stem cells sensitizes them to cell death signals. However, it is unclear that mobilization of the cell cycle can eliminate quiescent cancer stem-like cells in solid cancers. Thus, we explored the use of a genetically-engineered telomerase-specific oncolytic adenovirus, OBP-301, to mobilize the cell cycle and kill quiescent cancer stem-like cells. Experimental Design: We established CD133(+) cancer stem-like cells from human gastric cancer MKN45 and MKN7 cells. We investigated the efficacy of OBP-301 against quiescent cancer stem-like cells. We visualized the treatment dynamics of OBP-301 killing of quiescent cancer stem-like cells in dormant tumor spheres and xenografts using a fluorescent ubiquitination cell-cycle indicator (FUCCI). Results: CD133(+) gastric cancer cells had stemness properties. OBP-301 efficiently killed CD133(+) cancer stem-like cells resistant to chemoradiotherapy. OBP-301 induced cell-cycle mobilization from G(0)-G(1) to S/G(2)/M phases and subsequent cell death in quiescent CD133(+) cancer stem-like cells by mobilizing cell-cycle-related proteins. FUCCI enabled visualization of quiescent CD133(+) cancer stem-like cells and proliferating CD133(-) non-cancer stem-like cells. Three-dimensional visualization of the cell-cycle behavior in tumor spheres showed that CD133(+) cancer stem-like cells maintained stemness by remaining in G(0)-G(1) phase. We showed that OBP-301 mobilized quiescent cancer stem-like cells in tumor spheres and xenografts into S/G(2)/M phases where they lost viability and cancer stem-like cell properties and became chemosensitive. Conclusion: Oncolytic adenoviralinfection is an effective mechanism of cancer cell killing in solid cancer and can be a new therapeutic paradigm to eliminate quiescent cancer stem-like cells. No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 0340-7004 61 11 2012 Mechanism of resistance to trastuzumab and molecular sensitization via ADCC activation by exogenous expression of HER2-extracellular domain in human cancer cells 1905 1916 EN Ryosuke Yoshida Hiroshi Tazawa Yuuri Hashimoto Shuya Yano Teppei Onishi Tsuyoshi Sasaki Yasuhiro Shirakawa Hiroyuki Kishimoto Futoshi Uno Masahiko Nishizaki Shunsuke Kagawa Toshiyoshi Fujiwara Trastuzumab, a humanized antibody targeting HER2, exhibits remarkable therapeutic efficacy against HER2-positive breast and gastric cancers; however, acquired resistance presents a formidable obstacle to long-term tumor responses in the majority of patients. Here, we show the mechanism of resistance to trastuzumab in HER2-positive human cancer cells and explore the molecular sensitization by exogenous expression of HER2-extracellular domain (ECD) in HER2-negative or trastuzumab-resistant human cancer cells. We found that long-term exposure to trastuzumab induced resistance in HER2-positive cancer cells; HER2 expression was downregulated, and antibody-dependent cellular cytotoxicity (ADCC) activity was impaired. We next examined the hypothesis that trastuzumab-resistant cells could be re-sensitized by the transfer of non-functional HER2-ECD. Exogenous HER2-ECD expression induced by the stable transfection of a plasmid vector or infection with a replication-deficient adenovirus vector had no apparent effect on the signaling pathway, but strongly enhanced ADCC activity in low HER2-expressing or trastuzumab-resistant human cancer cells. Our data indicate that restoration of HER2-ECD expression sensitizes HER2-negative or HER2-downregulated human cancer cells to trastuzumab-mediated ADCC, an outcome that has important implications for the treatment of human cancers. No potential conflict of interest relevant to this article was reported.