Yasuhito Tonomoto

Downregulation of KiSS‐1 expression is responsible for tumor invasion and worse prognosis in gastric carcinoma

KiSS‐1 is a promising candidate tumor‐suppressor gene and may play a key role in the metastatic cascade. The expression profile and the role of KiSS‐1 in cancer progression are largely unknown in most of the cancers, including gastric cancer. In this study, KiSS‐1 expression was evaluated by RNase protection assay and localization was done by in situ hybridization in 40 gastric cancers and their adjacent normal gastric mucosa. For comparison with clinicopathologic characteristics and patient prognosis, all patients were divided into 2 groups having high and low KiSS‐1 expression by using the median as the cutoff value of KiSS‐1 expression as determined by the RNase protection assay. Gastric cancers with low KiSS‐1 had frequent venous invasion, distant metastasis and tumor recurrence. Accordingly, patients with low KiSS‐1‐expressing tumors had a significantly worse overall and disease‐free survival. In multivariate analysis, KiSS‐1 became the strongest independent prognostic factor among the conventional prognosticators for gastric cancer patients. Collectively, these findings suggest that KiSS‐1 may play a crucial role in gastric cancer invasion and could be a useful target for therapeutic intervention.

Expression of Trefoil Factor Family Members Correlates with Patient Prognosis and Neoangiogenesis

Purpose: Trefoil factor family (TFF) peptides are thought to contribute to epithelial protection and restitution by virtue of their protease-resistant nature and their strong affinity for mucins. However, they are often overexpressed in tumors, where they seem to be negative prognostic factors, possibly contributing to tumor spread, although the precise mechanisms have not been defined. Experimental Design: Tissue sections from 111 patients with curatively resected advanced gastric carcinoma were immunohistochemically stained for TFF2, ITF (TFF3), and CD34. Microvessel density was expressed as number and area of microvessels. Results were correlated with clinicopathological characteristics and patient survival. Results: Forty-nine (44.1%) and 41 (36.9%) tumors were immunohistochemically positive for TFF3 and TFF2, respectively. Among the various clinicopathologic variables, overexpression of TFF3 had a significant correlation with patient age only. In addition, a significantly higher prevalence of positive TFF2 staining was detected in large, diffuse tumors and in tumors with lymph node metastasis. The number of microvessels had a significant correlation with both TFF3 and TFF2 staining, whereas the area of microvessels had a significant correlation only with TFF3 staining. Both TFF3 and TFF2 were independent predictors of a worse disease-free survival. TFF3 had a gender-specific negative survival advantage, with a 91.3% disease-free survival in female patients with TFF3-negative advanced gastric carcinoma. Conclusions: Induction of increased tumor vascularity might be one of the mechanisms by which TFFs confer metastatic phenotype and frequent disease recurrence in gastric carcinomas. Female patients with TFF3-negative advanced gastric carcinoma have comparable survival as that reported for patients with early gastric carcinoma.

Surgical treatment of superficial esophageal cancer

ObjectiveThe worldwide incidence of superficial esophageal cancer (SEC) is increasing. The aim of this study is to review the systematic surgical outcomes of esophagectomy for SEC.Data sourcesOnly manuscripts written in English and written between 1980 and 2003 were selected from MEDLINE. The keywords consisting of superficial esophageal cancer, early esophageal cancer, and early stage or superficial stage or stage I in esophageal cancer were searched.Study selectionThere were no exclusion criteria for published information relevant to the topics. The most representative articles were selected when there were several articles from the same institution. Case reports were excluded.Data extractionsThirty-two manuscripts were finally collected from MEDLINE and eight articles were also added from reference lists of the pertinent literatures. In evaluating the statistical analysis of the complications of the reported literature, collective method was used.Data synthesisThe collected information was organized.ConclusionsThe conclusions drawn from those articles showed that the overall prevalence of SEC accounted around 10% and increased to 25% in the 2000s. The overall incidence of lymph node metastasis of SEC was about 25% and its incidences in mucosal and submucosal cancer were 5 and 35%, respectively. The percentage of the cases of squamous cell carcinoma (SCC) vs adenocarcinoma (AC) widely varied depending on the geographic locations reported; most SCC cases were from the Asian countries and most AC cases were from the European countries. Clinical significance of multimodal treatment for SEC has dramatically developed in the recent era and could provide various potential therapeutic options for SEC. These concepts make it possible to individualize surgical management of SEC as part of various multimodal treatments. The operative approaches for SEC varied from minimally invasive thoracoscopic esophagectomy, limited transabdominal distal esophagectomy, conventional transthoracic esophagectomy, transhiatal esophagectomy without thoracotomy, en bloc esophagectomy, and to extended esophagectomy with a complete three-field lymph node dissection. A 5-year overall survival rate of SEC after esophagectomy was good (46 to 83%) to excellent (71 and 100%) for mucosal SEC, but far from satisfactory (33 and 78%) for submucosal SEC. Early diagnosis, development of multimodal treatment, standardization of the surgical procedure including routine lymph node dissection, and improved perioperative management of patients have led to a better survival for patients with SEC.

Differential Expression of RUNX Genes in Human Esophageal Squamous Cell Carcinoma: Downregulation of RUNX3 Worsens Patient Prognosis

Background: The RUNX proteins are a family of transcriptional factors that have essential functions during embryogenesis and development, whereas deregulation in expression of RUNXs is often linked to tumor formation. To date, there has been no study describing the precise expression, prognostic impact and methylation status of RUNXs in esophageal squamous cell carcinoma. Methods: Resected specimens from 61 patients with esophageal SCC were used to identify the expression of RUNX1, RUNX2 and RUNX3 by real-time RT-PCR. Localization of mRNA was done by in situ hybridization, expression of Smad4 was evaluated by immunohistochemistry, and the methylation status of RUNX3 was analyzed by methylation-specific PCR. Results: RUNX3 had a significant impact on patient prognosis with worse survival in the RUNX3-negative group. In early tumors (T1/T2), the prevalence of lymph vessel invasion and the number of metastatic lymph nodes were significantly higher in RUNX3-negative tumors. Furthermore, RUNX3 became a strong prognostic factor only in Smad4-positive tumors. Also, the methylation status of the RUNX3 promoter had a significant correlation with the loss of RUNX3 expression. Conclusion: Downregulation of RUNX3 may play a role in disease progression of esophageal SCC, and hypermethylation of the promoter region might be one of the crucial pathways to silence RUNX3 gene.

FR-167653, a selective p38 MAPK inhibitor, exerts salutary effect on liver cirrhosis through downregulation of Runx2

Liver cirrhosis remains a difficult-to-treat disease with a substantial morbidity and mortality rate. There is an emerging body of data purporting a pivotal role of the activated p38 mitogen-activated protein kinase (MAPK) in the process of cirrhosis. Several anticirrhotic agents have been developed over the past few years, and most of them exert their effects by indirectly inhibiting the p38 pathway. Effect of a selective p38 inhibitor is yet to be reported. In this study, we evaluated the salutary effect of FR-167653 (FR), a selective p38 inhibitor, in a carbon tetrachloride (CCl4)-induced rat cirrhotic model. Twenty rats were assigned into four groups: Sham, olive oil only; Control, CCl4 in olive oil; FR50, FR 50 mg/kg/day and CCl4; and FR100, FR 100 mg/kg/day and CCl4. FR dose-dependently inhibited activation of p38 and had an ameliorating effect on cirrhosis formation. Significant dose-dependent reduction in α-smooth muscle actin immunostaining and hydroxyproline content of the liver was noticed in the FR-treated rats. Also densitometric analysis showed a significant reduction in azan-stained area in the FR-treated rats. These fibrotic changes were observed in the myofibroblasts including the hepatic stellate cells and portal fibroblasts. mRNA expression of runt-related protein 2 (Runx2), a profibrogenic transcription factor, was significantly low in FR-treated livers, indicating that Runx2 might be a key downstream regulator of the p38 pathway. A similar reduction in expression of Smad4 and tissue inhibitor of metalloproteinase-1 was noticed in the FR-treated rats. In conclusion, FR treatment exerted a significant beneficial effect in a CCl4-induced rat cirrhotic model. The ameliorating effect of FR could be partially attributable to an inhibition of the Smad4/p38/Runx2 axis in the cirrhotic liver.

Inherent potential for production of tumor necrosis factor-α by human intestinal macrophages

Background and aimsTumor necrosis factor (TNF) production by the macrophages in intestines appears to play a critical role in the pathogenesis of Crohns disease (CD). However, it is reported that resident intestinal macrophages (both colonic and small-bowel) do not produce TNF after lipopolysaccharide (LPS) stimulation. It has not yet been proven whether or not intestinal macrophages have an inherent potential to produce TNF. The purpose of this study is to answer this question.Materials and methodsColonic macrophages were isolated from lamina propria of human large intestine and stimulated with a variety of substances: LPS, a lipid A derivative (ONO-4007), killed Streptococcus bacterial body (OK-432), phorbol 12-myristate 13-acetate, and lectins (pokeweed mitogen and Sarcophaga lectin).ResultsColonic macrophages were phenotypically negative for CD14 and positive for CD68 and produced very little TNF in response to LPS, as reported previously. Of the substances tested, only Sarcophaga lectin, which is a defense protein of fleshflies (Sarcophaga peregrina), induced TNF production by the intestinal macrophages. In addition, when the colonic macrophages were cultured on immunoglobulin-A-coated dishes, their characteristic response to LPS was altered, and they produced TNF at a level 6.6 times higher than when on collagen-coated dishes.ConclusionColonic macrophages have an inherent ability to produce TNF. Activation of colonic macrophages by unknown substances may contribute to the induction of TNF production, which causes the intestinal inflammation of CD.

The use of minimally invasive surgery for lymph node recurrence after endoscopic mucosal resection of superficial esophageal cancer

A 73-year-old man was diagnosed with superficial esophageal cancer, and endoscopic mucosal resection was performed. Histologically, the lesion was found to be a squamous cell carcinoma invading the muscularis mucosae without vascular invasion. The patient was followed without being given adjuvant therapy, and lymph node recurrence along the lesser curvature of the stomach was found after 2.5 years. He underwent laparoscopic removal of the metastatic lymph node and cholecystectomy for cholecystolithiasis. He had two courses of adjuvant chemotherapy and showed no recurrence during 3 years of observation. Although the effectiveness of surgical resection for nodal recurrence of esophageal cancer remains controversial, this case highlights the possibility of salvage resection using minimally invasive surgery.