Tomohiko Miyatani

Sonic hedgehog relates to colorectal carcinogenesis

AimThe activation of Hedgehog signaling, which is critical to normal mammalian gastrointestinal development, is implicated in the development of various tumors, including colorectal cancer. In the pancreas, a precursor lesion overexpresses the Sonic hedgehog (Shh) when compared with normal tissue and cancer. The present study was designed to investigate Shh related protein expression in hyperplastic polyps and the adenoma-carcinoma sequence in the colon and rectum.MethodsSeventeen hyperplastic polyps, 24 adenomas of the colon, 69 adenocarcinomas (31 well-differentiated, 38 moderately-differentiated), and 30 normal colon samples were used in the study. We checked the expression of Shh, both patched (Ptch) and smoothened (Smo), by immunohistochemistry and compared the expression rate of each group.ResultsAlmost all adenomas, 22 of 23 (96%), expressed Shh. In other groups, 4 of 17 hyperplastic polyps (24%), 7 of 31 well-differentiated adenocarcinomas (23%), 13 of 38 moderately-differentiated adenocarcinomas (34%) and none of the 30 normal samples expressed Shh. The rate of expression in Ptch and Smo gradually increased in accordance with tumor progression.ConclusionThis result indicates that Shh-related carcinogenesis and Shh expression may be a trigger for the adenoma-carcinoma sequence. This study suggests a potential therapeutic target of hedgehog blockade in carcinogenesis.

Expression of histone deacetylase 1 and metastasis-associated protein 1 as prognostic factors in colon cancer

Histone deacetylase 1 (HDAC1) and metastasis-associated protein 1 (MTA1) form the nucleosome remodeling and histone deacetylation (NuRD) complex and may possibly play a central role in cancer development. However, limited data has been reported regarding the expression of both HDAC1 and MTA1. The aim of the present study was to clarify the clinical role of HDAC1 and MTA1 expression in colon cancer. Seventy-four patients with colon cancer, who underwent colectomy at our institution, were enrolled in this study. Expression of HDAC1 and MTA1 was examined immunohistochemically. The patients were divided into four groups: HDAC1-positive group (n=58), HDAC1-negative group (n=16), MTA1-positive group (n=38) and MTA1-negative group (n=36). Clinicopathological factors and survival rates were compared between the groups. Regarding the clinicopathological factors, the depth of tumor invasion and stage correlated significantly with HDAC1 expression (p<0.05). Age, depth of tumor invasion and vascular invasion tended to correlate with MTA1 expression. The 5-year survival rate in the HDAC1-positive group (55.1%) was significantly worse compared to the HDAC1-negative group (86.5%) (p<0.05), and the 5-year survival rate of the MTA1-positive group (50.5%) was significantly worse than that of the MTA1-negative group (73.1%) (p=0.05). In patients with stages II-IV and curability A, B, the survival rate in those with HDAC1-positive expression was significantly worse than those with HDAC1-negative expression (p<0.05), and the survival rate of the MTA1-positive group tended to be worse than that of the MTA1-negative group (p=0.07). Overall survival in both the HDAC1 and MTA1-positive groups was significantly worse than overall survival of the other groups (p<0.05). Disease-free survival in both the HDAC1- and MTA1-positive groups, among patients with stages II-IV and curability A, B, was also significantly worse than that of the other groups (p<0.05). HDAC1 and MTA1 expression levels were significantly related to poorer prognosis. Therefore, HDAC1 and MTA1 expression levels are potential prognostic indicators for colon cancer.

Platelet-derived endothelial cell growth factor/thymidine phosphorylase inhibitor augments radiotherapeutic efficacy in experimental colorectal cancer

PURPOSES A lot of radiosensitizers have been developed. However, there are few to be available in the clinical setting. Thymidine phosphorylase inhibitor (TPI) regulates the phosphorolysis of thymidine to thymine and 2-deoxy-d-ribose-1-phosphate which is essential for tumor angiogenesis. The aim of this study is to evaluate whether TPI augments the radiotherapy for colorectal cancer in vitro and in vivo studies. MATERIALS AND METHODS The cytotoxicity of TPI with irradiation on HT29 and HCT116 cells was examined using MTT- and colony formation assay. At 10days post-inoculation, HT29 bearing orthotopic model mice (n=28) were divided into four groups and orally treated with TPI- (50mg/kg/day for 2weeks), radiation (RT, 2Gy×4: Total 8Gy), their combination or the vehicle. The mechanisms underlying the efficacy were assessed genomically and immunohistochemically. RESULTS Compared to each single treatment, the combination of TPI and RT synergistically inhibited the cell viability in a time- and dose-dependent manner. In the HT-29 bearing mice, the combination of TPI and RT reduced the tumor growth compared with RT alone. Notably, the mRNA levels of VEGF, TGF-β and, Rad51 and the protein expressions of VEGF and CD34 were significantly lower in the combination than the others. Furthermore, the combination markedly increased the TUNEL-positive cells, suggesting that TPI augments the cancer cell death through inhibition of angiogenesis and DNA repair system in the radiotherapy. CONCLUSIONS Our study first demonstrated that the combination of TPI and irradiation was effective in colon cancer. TPI would provide a promising therapeutic strategy as a radiosensitizer.

Squamous Cell Carcinoma of the Descending Colon: Report of a Case and Literature Review

It is very rare that squamous cell carcinoma (SCC) arises from colorectal epithelium. An 89-year-old man was treated in 2001 with chief complaints of anorexia, abdominal pain, and low grade fever. The histological diagnosis as SCC was determined by biopsy during a colonoscopy. We diagnosed primary SCC of the colon because except in the colon no malignant lesions were found by systemic CT. Surgical complete resection was performed. However, he died three months after surgical resection because of hepatic metastasis and cachexia. The prognosis of this disease seems to be worse than that of adenocarcinoma.

Benefits of simultaneous laparoscopic resection of primary colorectal cancer and liver metastases

Recently, consensus on the optimal strategy for resectable synchronous colorectal liver metastases (LM) seems to have shifted toward simultaneous resection. However, there are still relatively few reports about simultaneous laparoscopic resection. The aim of this study is to evaluate the outcomes of patients who underwent simultaneous laparoscopic resection.

Short-term results of laparoscopic surgery after preoperative chemoradiation for clinically staged T3 and T4 rectal cancer

The feasibility of laparoscopic surgery for clinically staged T3 and T4 rectal cancer has not been clearly defined specifically in cases following preoperative chemoradiation therapy (CRT). Our aim was to investigate the feasibility of laparoscopic surgery after preoperative CRT for clinically staged T3 and T4 rectal cancer.

Preoperative radiotherapy combined with S-1 for advanced lower rectal cancer: phase I trial.

BACKGROUND/AIMS S-1 based chemoradiation is the recommended treatment for rectal cancer; however, the optimal scheduling and dosing are not yet established. A Phase I study was conducted to determine the maximum tolerated dose (MTD) of S-1 with radiotherapy (RT). Endpoints were the toxicity profile of this regimen and to determine the recommended dose (RD). METHODOLOGY Conformal RT was given using 4 fields at daily fractions of 2Gy on 5 days per week to a total dose of 40Gy. Concurrently S-1 was given twice daily throughout RT. Eligible patients had a newly diagnosed clinical stage T3-4 N0-2 M0 rectal adenocarcinoma located within 12cm of the anal verge suitable for curative resection. Surgery was performed 6 weeks from completion of preoperative chemoradiotherapy. The dose escalating from S-1 80mg/m2/day (Level 1) to 100mg/m2/day (Level 2). RESULTS Nine patients were valid for safety. In all patients, S-1 was administered. There was no dose-limiting toxicity (DLT) in patients treated at dose Level 1. Six patients were enrolled in the dose-escalation phase. At dose Level 2, two patients developed DLT and this was considered the MTD. Objective response according to RECIST were observed in 5 of 9 patients who had measurable disease (56%). CONCLUSIONS The RD of S-1 with concurrent RT was determined to be 80mg/m2/day. Preoperative RT combined with S-1 was feasible and well tolerated.

The Effect of Polysaccharide K with S-1 Based Chemotherapy in Advanced Gastric Cancer

BACKGROUND/AIMS Polysaccharide K (PSK) is widely used in Japan as a biological response modifier for cancer patients. We investigated the effects of PSK with S-1 based chemotherapy for advanced gastric cancer patients in immune response. METHODOLOGY Nine advanced gastric cancer patients who underwent chemotherapy at the University of Tokushima were included in this study. In all patients, 3g PSK was received orally and S-1 based chemotherapy for 2 weeks alternately for 8 weeks. Serial changes in immunological parameters (Foxp3, Natural killer (NK), CD4/CD8) were monitored. RESULTS The levels of Foxp3 at 8 weeks was significantly decreased compared with 2 weeks (4.26% vs. 3.11%). In NK activity at 8 weeks was significantly increased compared with 2 weeks (27% vs. 47%). CONCLUSIONS These results of this study suggested that chemotherapy with PSK improved the immune response in advanced gastric cancer patients. Especially Foxp3 was concerned in this mechanism.

Laparoscopic Removal of a Foreign Body in the Pelvic Cavity through One Port Using a Flexible Cholangioscope

Background: More than two trocar ports 12 mm in diameter were usually used to remove a foreign body from the peritoneal cavity using laparoscopic surgery. We designed a method of laparoscopic removal through a single port 5 mm in diameter and a flexible cholangioscope. Patients and Methods: The patient had a ventriculoperitoneal shunt (V-P shunt) catheter implanted for hydrocephalus of unknown cause in his 40s. Endoscopic marsupialization of the third ventricle was performed because of functional failure of the V-P shunt catheter 7 years after the implantation. A falling off of the V-P shunt catheter into the pelvic space was detected, and laparoscopic removal of the V-P shunt catheter was performed. A laparoscope was inserted through a trocar port 5 mm in diameter to confirm the location of the V-P shunt catheter following replacement of the flexible cholangioscope to grasp the catheter. The catheter was held using a snare catheter through the cholangioscope. The V-P shunt catheter was removed by pulling through the trocar port with the flexible cholangioscope. Conclusion: Laparoscopic removal is a good technique for removal of a foreign body in the peritoneal cavity. It enables one-port laparoscopic removal using a flexible cholangioscope.

Protein kinase Cι is a new prognostic factor in gastric cancer

PurposesProtein kinase Cι (PKCι) is an important oncogenic K-ras effector, and its expression is correlated with tumor angiogenesis. The role of PKCι in gastric cancer remains unclear. The aim of this study was to clarify the role of PKCι in gastric cancer.MethodsTwenty-eight patients with gastric cancer who underwent gastrectomy were enrolled in this study. The expression of PKCι mRNA was determined, as were the clinicopathological factors. The patients were divided into PKCι high and low expression groups. The 5-year survival rate, ERK mRNA level and VEGF mRNA level were compared between the two groups. The prognostic factors were investigated by a multivariate analysis.ResultsHigh expression of PKCι was observed to be associated with a lack of differentiation, tumor invasion ≥muscularis propria≤, stage III and IV disease and peritoneal dissemination. The 5-year survival rate in the PKCι high group was lower than that in the PKCι low group. The multivariate analysis revealed that a high expression level of PKCι was an independent prognostic factor. The expression levels of ERK and VEGF in the PKCι high group were higher than those in the PKCι low group.ConclusionOur results indicate that PKCι is correlated with tumor progression and angiogenesis. PKCι may be a new prognostic factor for gastric cancer.