Nobuhiro Kurita

Gastric cancer is one of the most common types of cancer. Cancer stem cells (CSCs) have been reported to play important roles in multiple cancer types. This study investigated the correlation between cluster of differentiation 133 (CD133), histone deacetylase 1 (HDAC1) and thrombospondin-1 (THBS1) expression in advanced gastric cancer. The study included 65 patients with gastric cancer with recurrence after surgery. Expression of CD133, HDAC1 and THBS1 was examined by immunohistochemistry. Prognostic factors were investigated by multivariate analysis using Cox's proportional hazard model. Clinicopathological variables, including survival, of patients positive for CD133 expression (n=6, 23%), were compared with those without CD133 expression (n=20, 77%). Positive HDAC1 expression and THBS1 expression were observed in 34 (52%) and 17 (26%) patients, respectively. Using univariate analysis, positive expression of CD133 and negative expression of THBS1 predicted significantly worse prognosis. Multivariate analysis revealed CD133-positive and THBS1-negative expression were independent prognostic indicators. CD133 expression and THBS1 expression were prognostic factors, and a negative relationship between HDAC and THBS1 was observed in advanced gastric cancer. These biomarkers may help determine postoperative treatment in patients with gastric cancer.

Bariatric surgery not only elicits weight loss but also rapidly resolves diabetes. However, the mechanisms remain unclear. The present study investigates how diabetes and liver steatosis are improved after duodenal-jejunal bypass (DJB) compared with a glucagon-like peptide-1 (GLP-1) analog and correlations between bile acids and GLP-1 secretion. We initially determined the effects of bile acids on GLP-1 in vitro and then assigned 12 male 16-week-old Otsuka Long-Evans Tokushima Fatty rats to groups that underwent DJB, a sham operation, or were treated with the GLP-1 receptor agonist, liraglutide (n = 4 each). Blood glucose, insulin, GLP-1, serum bile acids, liver steatosis, and the number of GLP-1 positive cells (L cells) in the small intestine and colon were investigated in the three groups at eight weeks postoperatively. Levels of GLP-1mRNA were upregulated and GLP-1 secretion increased in cells incubated with bile acids in vitro. Weight gain was suppressed more in the DJB than in the sham group in vivo. Diabetes was more improved and GLP-1 levels were significantly higher in the DJB than in the sham group. Serum bile acids were significantly increased, the number of L cells in the ileum was upregulated compared with the sham group, and liver steatosis was significantly improved in the DJB compared with the other two groups. Duodenal-jejunal bypass might improve diabetes and liver steatosis by enhancing GLP-1 secretion through increasing serum bile acids and the proliferation of L cells in the ileum, compared with liraglutide.

Backround: Most solid cancers including colon cancer are believed to be initiated from and maintained by cancer stem cells (CSCs), that are responsible for treatment resistance, resulting in tumor relapse. The aim of this study was to clarify the possible role of the Sonic Hedgehog (Shh) signaling pathway in the regulation of cancer stem cells. The HCT-116 cell line was cultured with fetal bovine serum in RPMI-1640 medium and its sphere was grown in serum-free non-adherent culture. Gene expressions were analyzed by quantitative real-time polymerase chain reaction (qRT-PCR) from cells treated with and without cyclopamine. HCT-116 sphere-derived cells grown in serum-free, non-adherent culture, showed significantly increased expression of stem cell markers, Shh downstream genes and epithelial-mesenchymal transition (EMT) markers compared to parental cells grown in conventional culture. The expression of stemness markers, Shh downstream genes and EMT markers were higher in cancer spheres than the parental cell line and down-regulated by cyclopamine treatment in a dose-dependent manner. Overall, these findings show that cyclopamine treatment could down-regulate the expression of stemness markers, shh downstream genes and EMT markers on HCT-116 spheres.

Recent studies have demonstrated the efficacy of irradiation from light emitting diodes (LED) for wound healing, anti-inflammation and anticancer therapies. However, little is known about the effects of visible light in colon cancer cells. The purpose of this study was to evaluate the biological response (including gene expression changes) of human colon cancer cells to different wavelengths of LED irradiation. Human colon cancer cells (HT29 or HCT116) were seeded onto laboratory dishes that were then put on LED irradiation equipment with a 465 nm-, 525 nm-, or 635 nm-LED. Irradiation at 15 or 30 mW was performed 10 min/day, each day for 5 days. The cell counting kit8 was then used to measure cell viability. Apoptosis and expression of several mRNAs (caspase, MAPK and autophagy pathway) in HT29 cultures irradiated with 465 nm LED were evaluated via AnnexinV/PI and RT-PCR, respectively. Viability of HT29 and HCT116 cells was lower in 465 nm-LED irradiated cultures than in control cultures, but viability of HT29 cells did not differ between control cultures and 525 nm-LED or 635 nm-LED irradiated cultures. Moreover, the expression of FAS, caspase-3, capase-8, and JUK were significantly higher in 465 nm-LED irradiated cultures than in control cultures, and expression of ERK1/2 and LC3 was lower in blue-irradiated cells. LED irradiation at 465 nm inhibited the proliferation of HT29 cells and of HCT116 cells. Notably, LED irradiation at 465 nm promoted apoptosis inHT29 cultures via the extrinsic apoptosis pathway and the MAPK pathway.

Cancer stem cells (CSC) was reported to play an important role in various kinds of cancer. CD133 is one of the cancer stem cell markers in solid cancers. However, the correlation between CD133 expression and the clinicopathological factors in colorectal cancer (CRC) remains unclear. Forty patients with CRC who underwent operations were enrolled. Expression of CD133 was investigated by immunohistochemistry (IHC). The staining was observed in the cytoplasm of cancer cells and the patients who have the staining were defined as CD133-positive cases. The patients were divided into two groups: the CD133-positive group (n = 22) and negative group (n = 18). Clinicopathological factors were compared between the two groups. The prognostic factors were investigated by multivariate analysis. In the CD133-positive group, the incidence of lymph node and liver metastasis, lymphatic and venous invasion, as well as the progression of stage of cancer were higher than that in the CD133-negative group. The 5-year survival rate and the disease-free survival rate in the CD133-positive group were lower than that in the CD133-negative group. The multivariate analysis revealed that CD133 expression tended to be an independent prognostic factor. CD133 expression is correlated with poor prognosis in CRC.

Over expression of Stathmin1 (STMN1), activation-induced cytidine deaminase (AID) and protein kinase C iota (PKCi) proteins participate in the regulation of carcinogenesis. In the present study, we investigated the expression of STMN1 in patients with gastric adenocarcinoma and also determined the correlation of STMN1 with AID and PKCi proteins. This study was conducted in the Tokushima University Hospital between September 2009 and September 2010 on a total of 59 patients with gastric adenocarcinoma. Stathmin1, AID and PKCi protein expressions were evaluated by immuno-histochemistry in gastric adenocarcinoma. A strong expression of STMN1 was significantly associated with gender- and poorly differentiated gastric adenocarcinoma (p<0.05). A high mRNA level of STMN1 was found in the tumor tissue of gastric adenocarcinoma compared to non-tumor tissue (p<0.05). In addition, STMN1 expression was significantly correlated with AID and PKCi protein expressions in gastric adenocarcinoma (p<0.05). High mRNA level of the Stathmin1 gene was significantly expressed in gastric tumor tissue than non-tumor and strong expression of STMN1 protein is correlated with poorly-differentiated gastric adenocarcinoma.

Laparoscopic surgery reduces the risk of postoperative adhesion compared with open surgery. The aim of this study was to assess the advantage of laparoscopic surgery in terms of postoperative adhesion. Eleven patients participated in this study (laparoscopic surgery: 6 patients, open surgery: 5 patients). Body temperature, heart rate, the duration until the first postoperative flatus and the beginning of diet were investigated on postoperative day 0, 1, 3, and 5, respectively. Serum level of WBC and CRP, PAI-1 and IFN-gamma level in the drainage tube were also measured at the same time. There is no significant difference between the two groups in body temperature. The laparoscopic group revealed significantly lower WBC on POD 0 and CRP on POD 1 compared with the open group. PAI-1 was significantly lower on POD 3 and 5 in the laparoscopic group. IFN-gamma in the laparoscopic group tended to be suppressed compared with the open group. Laparoscopic surgery may decrease the risk of postoperative abdominal adhesion compared with open surgery by suppressing early postoperative inflammation.

The aim of this study is to investigate the mechanisms of improvement in insulin resistance after duodenal-jejunal bypass (DIB), especially regarding the correlation between bile acids and glucagon-like peptide-1 (GLP-1). SD rats were divided into two groups: DIB or Sham group. Blood glucose, insulin, GLP-1, bile acids, and the number of L cells in the small intestine were investigated three weeks after the operations. Next, to assess the effect of the bile acids on GLP-1 secretion in ileum, bile diversion model (=inhibition of rapid bile exposure to the ileum; BD group) were performed and postoperative glycemic parameters were measured. DJB improved insulin resistance and increased GLP-1 compared with sham. Higher bile acids in DJB were found than that in sham. The number of L cells in the common limb of DJB was increased compared with that in the distal segment of sham. In BD group, insulin resistance had not improved. GLP-1, bile acids, and the number of L cells revealed no significant changes compared with sham. DJB has a potential to improve insulin resistance, which may be related to enhanced GLP-1 secretion through the increase of bile acids in the common limb of the small intestine.

Gastric adenocarcinoma is one of the most common malignant tumors and the leading cause of malignancy-related death worldwide. Studies have reported overexpression of activation-induced cytidine deaminase (AID) and protein kinase c iota (PKCi) proteins showing involvement in the regulation of carcinogenesis. In the present study, we investigated the expression of AID and PKCi in patients with gastric adenocarcinoma and determined the correlation between these proteins. This study was conducted between September 2009 and September 2010 on a total of 59 patients with gastric adenocarcinoma at the Tokushima University Hospital. AID, PKCi and mutated p53 protein expressions were evaluated by immunohistochemistry in gastric adenocarcinoma. High AID and PKCi expression was significantly (p<0.05) associated with poorly-differentiated gastric adenocarcinoma. In addition, PKCi expression was significantly correlated with clinicopathological findings such as a lymph node metastasis, and venous and lymphatic invasion (p<0.05). Furthermore, AID expression was significantly correlated with PKCi and mutated p53 protein expression in gastric adenocarcinoma (p<0.05). High AID and PKCi expressions were significantly correlated with poorly-differentiated gastric adenocarcinoma.

563 Background: Recent pharmacogenetic studies have revealed a significant association between uridine diphosphate-glucuronosyltransferase 1A1 (UGT1A1) polymorphisms *28 and *6 and toxicities such as severe diarrhea and neutropenia under treatment with irinotecan. Moreover, the latter of these two polymorphisms is specifically detected in East Asian populations. We performed a prospective study to determine the optimal dose of this drug depending on which polymorphism is present in order to maximize the effectiveness of therapy while avoiding side effects. Methods: 59 patients from 11 institutions were enrolled in this study. Patients were assigned to one of the following three groups: wild type (*1/*1), heterozygous (*28/*1, *6/*1), or homozygous (*28/*28, *6/*6*, *28/*6*). The double heterozygous state (*28/*6) was included within the homozygous group. Second-line FOLFIRI was administered, with the dose of irinotecan at 150 mg/m2, in the wild type and heterozygous groups and at 100 mg/m2 in the homozygous group. The incidences of severe toxicities according to UGT1A1 gene type, response rate, and progression-free survival were investigated. Results: 26 (44.1%) were assigned to the wild type group, 28 (47.4%) to the heterozygous group, and 5 (8.5%) to the homozygous group. Grade 3 or higher severe toxicities were observed in 8 patients (30.8%) in the wild type group, 5 (17.9%) in the heterozygous group, and 1 (20.0%) in the homozygous group. No significant difference was observed among the three groups. The most frequently observed severe toxicities were neutropenia, nausea, vomiting, and diarrhea. The overall response rate (complete response + partial response) was 2 patients (7.7%) in the wild type group, 2 (7.1%) in the heterozygous group, and none (0.0%) in the homozygous group. Conclusions: In terms of tolerability and safety, the present results suggest that irinotecan should be administered at a dose of 150mg/m2 in heterozygous patients and 100 mg/m2 in homozygous patients receiving second-line FOLFIRI.