Shingo Higaki

Endoscopic ultrasonography for diagnosis of submucosal invasion in early gastric cancer

Abstract: Endoscopic ultrasonography (EUS) is considered to be useful for deciding the treatment course for early gastric cancer. To determine reliable indications suggesting submucosal tumor invasion, we retrospectively analyzed EUS images of the hyperechoic third layer, which corresponds to the submucosa. The subjects enrolled in this study were 75 patients, with 78 gastric cancers (diagnosed as mucosal cancer without ulcerous changes on endoscopy and as histologically differentiated adenocarcinoma on biopsy), who were also examined by EUS. We retrospectively classi-fied EUS features of the third layer (submucosa) into five groups: (1) irregular narrowing, (2) budding sign, (3) multiple echo-free spots, (4) unclear, and (5) no changes. In endoscopically diagnosed gastric mucosal cancer, 16 of the 78 lesions were associated with histologic submucosal invasion. EUS features that were associated with a high incidence of histological submucosal tumor invasion were irregular narrowing (submucosal invasion, 60.0%) and the budding sign (85.7%), and 90.9% of lesions with either of these features had submucosal invasion of tumors when tumorous changes in the third layer exceeded 1 mm in depth. Endosonographic irregular narrowing and a budding sign of more than 1 mm in depth in the third layer are useful for the diagnosis of submucosal invasion in gastric cancers that are diagnosed as mucosal cancers without ulcerous change on endoscopy.

Increased expression of tumor necrosis factor-α messenger RNA in the intestinal mucosa of inflammatory bowel disease, particularly in patients with disease in the inactive phase

Background:Background: Tumor necrosis factor-α (TNF-α), may be involved in the pathogenesis of inflammatory bowel diseases (IBDs). The aim of this study was to evaluate the effect of TNF-α on the inflammatory activity of IBD. Methods: TNF-α mRNA expression in intestinal mucosal biopsy specimens from IBD patients [ulcerative colitis (UC), n= 54; and Crohns disease (CD), n= 11] was analyzed using a competitive polymerase chain reaction. The degree of macrophage infiltration was analyzed by immunohistochemistry, using an anti-human CD68 antibody. Results: TNF-α mRNA expression was increased in UC patients, corresponding to the inflammatory activity. However, in CD, TNF-α mRNA expression was not correlated with the endoscopic findings. Conclusions: We clarified that TNF-α mRNA expression was responsible for the inflammatory activity in UC. However, TNF-α mRNA expression was not correlated with the mucosal injury in CD.

TWIST1 hypermethylation is observed frequently in colorectal tumors and its overexpression is associated with unfavorable outcomes in patients with colorectal cancer

Although growing evidence demonstrates that TWIST1 is an interesting tumor biomarker, little is known about the clinical significance of TWIST1 expression and TWIST1 methylation in human primary colorectal cancer. In this study, we examined the association of TWIST1 expression and TWIST1 methylation with clinicopathologic features in human primary colorectal tumors. Primary colorectal cancer (CRC) specimens from 319 patients, corresponding normal colorectal nontumorous mucosa from 251 patients with cancer, and colorectal adenomas from 189 patients were used. Methylation and expression levels of TWIST1 were compared with clinicopathologic features. The TWIST1 methylation level was higher in colorectal adenoma and cancer than in normal colorectal mucosa. Elevated TWIST1 mRNA expression in normal colorectal mucosa in patients with CRC as well as in primary CRC specimens was associated with unfavorable outcomes. There was no correlation between TWIST1 methylation and TWIST1 expression. Our results suggest that TWIST1 methylation may be a useful biomarker for screening colorectal tumors. In addition, TWIST1 mRNA expression is a possible molecular marker for predicting the outcome in patients with CRC. Confirmatory studies using independent data sets are needed to confirm our findings.

Metaplastic polyp of the colon develops in response to inflammation.

Background: The metaplastic polyp of the colon is a non‐neoplastic lesion that is generally identified as white, flat and having a smooth surface. In general, this polyp is small, is less than 5 mm in diameter but is occasionally larger than 5 mm in diameter, and forms a swelling. The aims of the present study were to clarify the factors that determine the morphology of protruding metaplastic polyps. More specifically, we investigated whether the metaplastic polyp forms as a result of an abnormality in cell proliferation or inflammation of the region.

99mTc-HSA-D scintigraphy in the diagnosis of protein-losing gastroenteropathy due to secondary amyloidosis

Secondary amyloidosis frequently involves the gastrointestinal tract and may result in ulceration, hemorrhage, and protein-losing enteropathy. We report a patient with severe hypoalbuminemia in whom endoscopy revealed widespread ulceration of the small intestine. The protein-losing site was detected by99mTc-diethylene triamine pentaacetic acid human serum albumin (99mTc HSA-D) scintigraphy. This evidence suggests that the ulcers and mucosal lesions associated with amyloidosis contribute to abnormal protein loss from the gastrointestinal tract.

Relationship between matrix metalloproteinase-7 and pit pattern in early stage colorectal cancer

BACKGROUND The surface pit pattern of early stage colorectal cancer changes with tumor growth and invasion. It was postulated by us that the expression of matrix metalloproteinase-7 is related to tumor invasiveness and disturbance of the pit pattern. METHODS Sixty-eight colorectal epithelial tumors were examined, and the pit pattern was classified by stereoscopic microscopy. Immunostaining for matrix metalloproteinase-7 and its substrate laminin were performed. RESULTS The rate of matrix metalloproteinase-7 positive staining was significantly higher for mucosal (70.6%) and submucosal cancer (80.0%) than for adenoma (18.6%) (p<0.0083). The rate of matrix metalloproteinase-7 positive specimens was significantly higher for type IV and type V compared with type III pit patterns. Where the tumor surface was positive for matrix metalloproteinase-7, expression of laminin was negative in 40% of specimens with a type IV pit pattern and 100% of those with the type V pit pattern. CONCLUSIONS The results of this study indicate that expression of matrix metalloproteinase-7 is related to both the invasiveness of colorectal epithelial tumors and the disturbance of the pit pattern on the tumor surface.

Hypermethylation Status of APC Inversely Correlates With the Presence of Submucosal Invasion in Laterally Spreading Colorectal Tumors

Little is known about epigenetic alterations in laterally spreading colorectal tumors (LSTs). The goal of the present study was to elucidate the epigenetic background of LSTs and compare the methylation status of DNA CpG islands (CGIs) with clinicopathologic features. Methylation of MINT1, MINT2, MINT31, p16, O6‐methylguanine‐DNA methyltransferase (MGMT), adenomatous polyposis coli (APC), and human MutL homologue 1 (hMLH1) in 42 LSTs was assessed by methylation‐specific polymerase chain reaction (MSP) and compared with clinicopathologic parameters. The frequency of hypermethylation was 12.5% (4/32) for MINT1, 40.0% (16/40) for MINT2, 25.0% (10/40) for MINT31, 25.7% (9/35) for p16, 7.7% (3/39) for hMLH1, 26.5% (9/34) for MGMT, and 35.9% (14/39) for APC. APC methylation was inversely associated with submucosal invasion (P = 0.034), which was not found in any of 14 LST cases with APC methylation, whereas submucosal invasion was present in 8 of 25 (32.0%) cases without APC methylation. These data suggest that hypermethylation of APC could be a predictive marker for the absence of submucosal invasion of LSTs.

Highly sensitive stool DNA testing of Fusobacterium nucleatum as a marker for detection of colorectal tumours in a Japanese population.

Background Accumulating evidence shows an over-abundance of Fusobacterium nucleatum in colorectal tumour tissues. Although stool DNA testing of Fusobacterium nucleatum might be a potential marker for the detection of colorectal tumours, the difficulty in detecting Fusobacterium nucleatum in stool by conventional methods prevented further explorations. Therefore, we developed a droplet digital polymerase chain reaction (PCR) assay for detecting Fusobacterium nucleatum in stool and investigated its clinical utility in the management of colorectal tumours in a Japanese population. Methods Feces were collected from 60 healthy subjects (control group) and from 11 patients with colorectal non-advanced adenomas (non-advanced adenoma group), 19 patients with colorectal advanced adenoma/carcinoma in situ (advanced adenoma/carcinoma in situ (CIS) group) and 158 patients with colorectal cancer of stages I to IV (colorectal cancer group). Absolute copy numbers of Fusobacterium nucleatum were measured by droplet digital PCR. Results The median copy number of Fusobacterium nucleatum was 17.5 in the control group, 311 in the non-advanced adenoma group, 122 in the advanced adenoma/CIS group, and 317 in the colorectal cancer group. In comparison with that in the control group, the Fusobacterium nucleatum level was significantly higher in the non-advanced adenoma group, the advanced adenoma/CIS group and the colorectal cancer group. Conclusions This study illustrates the potential of stool DNA testing of Fusobacterium nucleatum by droplet digital PCR to detect individuals with colorectal tumours in a Japanese population.

Relationship between molecular markers and endoscopic findings in laterally spreading tumors

Background and Aim:  Characteristic clinicopathological features of laterally spreading tumors (LSTs) have been reported by endoscopists; however, only a few studies have been conducted on the biological features. These studies were not fully associated with the endoscopic findings of LSTs. The aim of this study was to estimate the biological features of each type of endoscopic finding of LST using two molecular markers, matrix metalloproteinase‐7 (MMP‐7) and β‐catenin.

Clinical significance of measuring blood coagulation factor XIIIA regularly and continuously in patients with Crohn's disease

Background:  The aim of the present paper was to determine the mechanism by which the level of coagulation factor XIIIA declines during the active phase of Crohn’s disease.