Nobuhisa Matsuhashi

Laparoscopic Technique and Initial Experience with Knotless, Unidirectional Barbed Suture Closure for Staple-Conserving, Delta-Shaped Gastroduodenostomy after Distal Gastrectomy

a a c h Since laparoscopy-assisted distal gastrectomy was first reported by Kitano and colleagues in 1994, laparoscopic gastrectomy (LG) for early gastric cancer (EGC) has been increasing rapidly and gaining popularity worldwide because it is associated with earlier patient recovery compared with open surgery. Improvements in instruments and aparoscopic technique have allowed for widespread accepance of LG, not only for various types of gastric resection ut also for totally laparoscopic procedures. In general, LG can be divided into laparoscopy-assisted and totally laparoscopic techniques. With laparoscopyassisted gastrectomy, although lymph node dissection is performed laparoscopically, transection of the stomach and the anastomosis are performed thorough an epigastric minilaparotomy. Performing the anastomosis in the narrow and restricted space is frequently difficult, especially for obese patients with thick abdominal walls or for patients with a small remnant stomach. Avoiding minilaparotomy also improves cosmesis, and performing all of the processes laparoscopically, including reconstruction of the digestive tract intracorporeally using laparoscopic linear stapling devices, offers the prospect of further improvements in quality of life. Recent results of retrospective studies have demonstrated the feasibility, safety, and efficiency of totally laparoscopic gastrectomy (TLG) when performed by high-volume laparoscopic surgeons, even with a relatively prolonged operating time. However, TLG as the disadvantages of technical difficulties in intracor-

Phase II/III study of second-line chemotherapy comparing irinotecan-alone with S-1 plus irinotecan in advanced gastric cancer refractory to first-line treatment with S-1 (JACCRO GC-05)

BACKGROUND In Japan, S-1 plus cisplatin has been used as first-line therapy for advanced gastric cancer (AGC). Patients with no response to first-line treatment with S-1 often receive a taxane-alone or irinotecan-alone as second-line treatment. However, second-line treatment with S-1 plus irinotecan is widely used in patients with AGC resistant to first-line S-1-based chemotherapy. The goal of this trial was to determine whether the consecutive use of S-1 plus irinotecan improves survival when compared with irinotecan-alone as second-line treatment for AGC. PATIENTS AND METHODS Patients who had disease progression during first-line S-1-based chemotherapy were randomly assigned to receive S-1 plus irinotecan or irinotecan-alone. The S-1 plus irinotecan group received oral S-1 (40-60 mg/m(2)) on days 1-14 and intravenous irinotecan (150 mg/m(2)) on day 1 of a 21-day cycle. The irinotecan-alone group received the same dose of irinotecan intravenously on day 1 of a 14-day cycle. The primary end point was overall survival (OS). RESULTS From February 2008 to May 2011, a total of 304 patients were enrolled. The median OS was 8.8 months in the S-1 plus irinotecan group and 9.5 months in the irinotecan-alone group. This difference was not significant (hazard ratio for death, 0.99; 95% confidence interval 0.78-1.25; P = 0.92). Grade 3 or higher toxicities were more common in the S-1 plus irinotecan group than in the irinotecan-alone group. CONCLUSION The consecutive use of S-1 plus irinotecan is not recommended as second-line treatment in patients who are refractory to S-1-based first-line chemotherapy. ClinicalTrials.gov ID: NCT00639327.

Positive feedback of DDX6/c-Myc/PTB1 regulated by miR-124 contributes to maintenance of the Warburg effect in colon cancer cells

The human DEAD/H-box RNA helicase gene DDX6 is a target of the t(11;14)(q23;q32) chromosomal translocation observed in human B-cell lymphoma, and the overexpression of its protein has been shown to cause malignant transformation. DDX6 has a variety of functions such as translation initiation, pre-mRNA splicing, ribosome assembly, and more. However, details of the regulatory mechanism of DDX6 and functions of DDX6 in cancer cells are largely unknown. On the other hand, the Warburg effect is a well-known feature of cancer cells. Pyruvate kinase in muscle (PKM), which is a rate-limiting glycolytic enzyme, has 2 isoforms, PKM1 and PKM2. It has been frequently reported that PKM2 is a tumor-specific isoform and promotes the Warburg effect. However, the functions of the PKM1 gene have been hardly mentioned. Here, we showed that DDX6 was overexpressed in colorectal cancer specimens and regulated by microRNA (miR)-124 in colon cancer cells. Also, a DDX6/c-Myc/PTB1 positive feedback circuit regulated by miR-124 was shown to be established and to contribute to maintenance of the Warburg effect. Moreover, we showed that knockdown of DDX6 induced mainly apoptosis through an imbalance of PKM gene expression, especially causing down-regulation of PKM1 in colon cancer cells. These results suggest that miR-124 is a fine tuner of the Warburg effect and that DDX6 is one of the key molecules in Warburg effect-related miR-124 targeting various genes.

Laparoscopic technique and safety experience with barbed suture closure for pelvic cavity after abdominoperineal resection.

BackgroundBetween April 2005 and December 2012, we performed laparoscopic colorectal resection with regional lymph node dissection on 273 cases of colorectal cancer patients. However, Laparoscopic rectal cancer surgery requires a high degree of skill. Any surgeon who is going to embark on these difficult resections should have at a minimum laparoscopic suturing skills in order to be able to close the peritoneal defect.MethodsIn laparoscopic surgery for rectal cancer, the intracorporeal suture technique required to close the pelvic cavity is very difficult. Barbed sutures have recently been proposed to facilitate laparoscopic suturing. Two patients with rectal cancer who underwent laparoscopic abdominoperineal resection (APR) with intracorporeal closure of the pelvic cavity from September to October 2012 were enrolled in this study.ResultsWe present our initial experience of two consecutive cases of intracorporeal closure of the pelvic cavity by totally laparoscopic APR. After clinical follow-up, the two patients have no complaints and have shown no signs of recurrence.ConclusionsWe hypothesized that barbed sutures could potentially improve the efficiency of intracorporeal closure of the pelvic cavity after laparoscopic APR. Further, we expect that use of the V-Loc™ will reduce intra-operative stress on the endoscopic surgeon.

MiR-133b inhibits growth of human gastric cancer cells by silencing pyruvate kinase muscle-splicer polypyrimidine tract-binding protein 1.

The metabolism in tumor cells shifts from oxidative phosphorylation to glycolysis even in an aerobic environment. This phenomenon is known as the Warburg effect. This effect is regulated mainly by polypyrimidine tract‐binding protein 1 (PTBP1), which is a splicer of the mRNA for the rate‐limiting enzymes of glycolysis, pyruvate kinase muscle 1 and 2 (PKM1 and PKM2). In the present study, we demonstrated that miR‐133b reduced PTBP1 expression at translational level and that the expression levels of miR‐133b were significantly downregulated in gastric cancer clinical samples and human cell lines, whereas the protein expression level of PTBP1 was upregulated in 80% of the 20 clinical samples of gastric cancer examined. Ectopic expression of miR‐133b and knockdown of PTBP1 in gastric cancer cells inhibited cell proliferation through the induction of autophagy by the switching of PKM isoform expression from PKM2‐dominant to PKM1‐dominant. The growth inhibition was partially canceled by an autophagy inhibitor 3‐MA or a reactive oxygen species scavenger N‐acetylcysteine. These findings indicated that miR‐133b acted as a tumor‐suppressor through negative regulation of the Warburg effect in gastric cancer cells.

Adenocarcinoma in bladder diverticulum, metastatic from gastric cancer

BackgroundMetastasis to the urinary bladder from gastric cancer is rare. Metastasis to a diverticulum of the bladder from gastric cancer is extremely rare. We report a case of isolated bladder metastasis from gastric cancer and invasion localized to the muscularis propria of the primary site (stomach).Case presentationA 90-year-old female presented with nausea and vomiting that was diagnosed as gastric cancer, the patient also had intermittent hematuria. Pelvic computed tomography identified an abnormally thickened area in the bladder wall that was diagnosed as a diverticulum of the bladder. A biopsy of the bladder wall revealed well differentiated tubular adenocarcinoma metastatic from gastric carcinoma.ConclusionAlmost all cases of bladder metastasis from gastric cancer had peritoneal dissemination. This particular presentation of bladder metastasis from gastric cancer, to the best of our knowledge, has not been previously reported.

A case of delayed rectal stenosis from severe pelvic fracture with massive bleeding successfully treated by bilateral internal iliac TAE: report on a patient survival.

An 89-year-old man with massive bleeding and severe pelvic fracture caused by traffic accident was brought to a nearby emergency room. On the time of arrival, his pelvic painworsened and gradually reached unstable conscious level. The Glasgow coma scale was E3V4M5. After initial evaluation and resuscitation, and 100 min after the injury, the patient was hospitalized at our trauma center, which can be reached within 15 min by a doctor helicopter. By the time of admission, approximately 2 l of acetated Ringer’s solution had been infused. Blood pressure and pulse rate were 80/42 mmHg 130/min, respectively. He underwent chest and pelvic radiography and sonography in the emergency room. We suspected that pelvic radiography revealed severe pelvic fracture. Blood tests revealedmany abnormalities, with a red blood cell count of 111×10/mm, Hb 3.4 g/dl, Ht 10.9 %, a white blood cell count of 11100/mm and a Creactive protein level of 0.05 mg/dl, pH 7.15, pCO2 42.30 mmHg, pO2 307.0 mmHg, lactate 88 mg/dl, and APACH II score 30. Pelvic radiography identified unstable pelvic fracture. Initial management with intravenous fluids and MAP FFP relieved bleeding shock, therefore, we performed an examination with internal iliac transcatheter arterial embolization (TAE). Pelvic arteriography, initiated 2 h after admission as blood transfusion continued, showed massive contrast extravasation from the bilateral iliac artery. Embolization was carried out with gelatin sponge pledgets and micro-size stainless steel coils. In addition, external fixation was carried out. He gradually recovered after the procedure. However, 14 days after transcatheter angiographic embolization, the abdominal pain increased gradually with abdominal distension and rectal stenosis. He could not discharge stool, which is an obstruction of the bowel called ileus. Delayed rectal stenosis resulted due to ischemic rectum because we conducted bilateral internal iliac artery TAE. Delayed rectal stenosis following pelvic fracture with trauma is extremely rare. It occurred after bilateral internal iliac artery embolization. He had been performed to low anterior resection for rectal cancer 20 years ago. Therefore, we hypothesized that he lacked superior rectal artery and vein and a few collateral flows. We performed the operation under general anesthesia and successfully carried out stoma by transverse colon. The patient recovered and was discharged on the 99th postoperative day. External fixation can reduce the bleeding from the fractured site and can control further bleeding caused by N. Matsuhashi (*) . T. Mizoguchi . N. Mitsuishi . K. Yoshimura . T. Ogiso . M. Tawada . S. Kuwabara . Y. Ikegame . M. Kato . K. Shirai . I. Toyoda . S. Ogura Department of Emergency and Disaster Medicine, Gifu University, 1-1 Yanagido, Gifu City, 501-1194, Japan e-mail: nobuhisa517@hotmail.com Tel.: +81-582-306448 Fax: +81-582-306451

Combination therapy with zoledronic acid and cetuximab effectively suppresses growth of colorectal cancer cells regardless of KRAS status

Targeted molecular therapy is an effective anticancer strategy. Anti‐EGFR monoclonal antibodies such as cetuximab (CTX) have been approved for the treatment of various malignancies, including colorectal cancer (CRC) with wild‐type KRAS. However, their efficacy in patients with KRAS mutations has not been established. Therefore, we investigated whether CTX treatment was effective as a single agent or in combination with zoledronic acid (ZOL) in human CRC cell lines with different KRAS status. CRC cell lines SW48 (wild‐type KRAS) and LS174T (mutant KRAS) were treated with ZOL, CTX and a combination of both drugs. Cytotoxicity was measured using the MTT assay. Changes in the levels of intracellular signaling proteins were evaluated using western blot analysis. Finally, we evaluated the efficacy of the combination treatment in an in vivo xenograft model. We observed that ZOL apparently inhibited growth in both cell lines, whereas CTX showed little effect. ZOL also increased the levels of unprenylated RAS. Combined ZOL and CTX treatment was synergistic in both cell lines and was associated with inhibition of the RAS‐MAPK and AKT‐mTOR signaling pathways. Furthermore, the combination treatment was more effective in suppressing the growth of xenografts derived from both SW48 and LS174T cells; this effect was associated with increased apoptosis. These results demonstrate that ZOL inhibits the growth of colon cancer cells regardless of KRAS status, and combination therapy using ZOL and CTX enhances this growth suppression. These findings suggest a novel strategy for the treatment of CRC independent of KRAS mutational status.

Phase II trial of neoadjuvant chemotherapy with docetaxel, nedaplatin, and S1 for advanced esophageal squamous cell carcinoma

Although standard chemotherapy for esophageal cancer patients is fluorouracil and cisplatin, the prognosis is still unsatisfactory. A new therapeutic regimen combining docetaxel, cisplatin, and 5‐fluorouracil was recently developed to improve both local and distant tumor control. We developed a new regimen of docetaxel, nedaplatin, and S1 (DGS) and previously reported the recommended dose in a phase I dose‐escalation study. We then undertook a phase II study of DGS for advanced esophageal squamous cell carcinoma. Patients with clinical stage IB/II/III disease were eligible. Patients received two courses of chemotherapy: docetaxel 35 mg/m2 with nedaplatin 40 mg/m2 on day 8, 80 mg/m2 S1 on days 1–14, and 2 weeks off. After completion of chemotherapy, patients underwent esophagectomy. The primary endpoint was the completion rate of protocol treatment (completion of two courses of preoperative chemotherapy and R0 surgery [no residual tumor]). We enrolled 32 patients. The completion rate of protocol treatment was 96.9%. During chemotherapy, the most common grade 3 or 4 toxicity was neutropenia (25.0%). No treatment‐related deaths were observed, and the incidence of operative morbidity was tolerable. The overall response rate after chemotherapy was 83.3%. This DGS regimen was well tolerated and highly active. This trial is registered with the University Hospital Medical Information Network (UMIN ID: 000014626).

Novel therapy for locally advanced triple-negative breast cancer

To evaluate a novel therapy for triple-negative breast cancer (TNBC), the biological responses to vitamin K3 (VK3) should be considered with the understanding of the features of breast cancer. In human breast cancer cell lines, the effects of VK3 on cell growth inhibition and the cellular signaling pathway were determined by MTT assay and western blotting. In the in vivo study, a subcutaneous tumor model of breast cancer was created, VK3 was injected into the subcutaneous tumors, and tumor size was measured. The IC50 of VK3 for breast cancer cells was calculated to be 11.3–25.1 μM. VK3 induced phosphorylation of whole tyrosine and epidermal growth factor receptor. VK3 mediated phosphorylation of extracellular signal-regulated kinase (ERK) and c-Jun NH2-terminal kinase (JNK) for 30 min. ERK but not JNK phosphorylation was maintained for at least 6 h. In contrast, another antioxidant agent, catalase, showed no effect on either ERK phosphorylation or growth inhibition. On built-up tumors under the skin of mice, local treatment with VK3 was effective in a time- and dose-dependent manner, and the experiments for total tumor volume also showed a dose-dependent effect of VK3. The expression of phosphorylated ERK was clearly detected at 10.9 times the control in tumor tissue, whereas ethanol itself showed no effect. In conclusion, ERK plays a critical role in VK3-induced growth inhibition, and it will be the focus of next steps in the development of molecular therapy for TNBC.