Helicobacter pylori-negative Differentiated Adenocarcinoma of the Stomach.

A 58-year-old Japanese man was diagnosed with differentiated adenocarcinoma of the stomach. Histological findings of the resected specimen revealed well- to moderately-differentiated tubular adenocarcinoma (tub1, tub2), 13 mm in diameter, which invaded into the submucosa (SM1, 300 µm) and lymphovascular lumen (ly1). Serum antibody against Helicobacter pylori (Hp) and the (13)C-urea breath test were negative, and there were no atrophic changes in the tumor-adjacent mucosa. The immunohistochemical analysis showed that gastric mucin (MUC5AC) was strongly positive and intestinal mucin (MUC2) was weakly and partially positive. According to these results, the final diagnosis of Hp-negative well-differentiated early gastric cancer was made.

Two distinct lymphocyte homing systems involved in the pathogenesis of chronic inflammatory gastrointestinal diseases.

Under normal and pathological conditions, lymphocyte migration into the gastrointestinal mucosa to form gut-associated lymphoid tissue is mediated by the L-selectin ligand peripheral lymph node addressin and the integrin α4ß7 ligand mucosal addressin cell adhesion molecule 1 (MAdCAM-1) expressed on high endothelial venules (HEVs) and HEV-like vessels. In this review, we discuss these two distinct lymphocyte homing systems involved in the pathogenesis of chronic inflammatory gastrointestinal diseases with reference to our and others' previously published works. We also describe a recently developed recombinant integrin α4ß7 heterodimeric IgG chimera that can be used as an immunohistochemical reagent to stain functional MAdCAM-1.

Hereditary angioedema in Japan: genetic analysis of 13 unrelated cases.

INTRODUCTION: The molecular bases and clinical features of hereditary angioedema (HAE) have not been systematically documented in Japan or in other Asian countries. Thus, the authors researched the genetic and clinical characteristics of Japanese patients with HAE. METHODS: The authors analyzed the CIINH gene for mutations in 13 unrelated Japanese patients with HAE by means of the polymerase chain reaction and nucleotide sequencing. In addition, the authors searched the literature from January 1969 to October 2010 on Japanese patients with HAE. RESULTS: Seven of the mutations found were novel, including 4 missense mutations (8728T>G, 8831C>A, 16661T>G and 16885C>A), 2 frameshift mutations (2281_2350del70, 14158delT) and 1 large deletion (at least 1 kb-length deletion including exon 4), whereas 6 mutations had previously been reported in European populations. CONCLUSIONS: The genetic and clinical characteristics in Japanese patients with HAE may be similar to those in Western patients although our sample size is small and the authors identified 7 novel mutations.

[A case of metachronous invasive ductal carcinoma concomitant with intraductal papillary-mucinous neoplasm (IPMN) of the pancreas, which could not be detected in contrast-enhanced CT scan performed 3 months ago].

A 61-year-old man had been followed up in another hospital under diagnosis of branch duct type IPMN for 4 years. Contrast-enhanced CT scan for regular check performed 3 months ago revealed no increase of IPMN and no pancreatic tumor. However, he complained of back pain after that, MRI was performed. It revealed a solid tumor in size of 25mm diameter at the head of pancreas. The tumor was apparent from IPMN in several imaging modalities. Pancreatoduodenectomy was performed under diagnosis of invasive ductal carcinoma concomitant with IPMN. Post-operative pathological findings revealed IPMN was adenoma with mild atypia, and solid tumor was diagnosed invasive ductal carcinoma with solitary minute liver metastasis.

Prominent expression of sialyl Lewis X-capped core 2-branched O-glycans on high endothelial venule-like vessels in gastric MALT lymphoma.

High endothelial venule (HEV)-like vessels have been observed in gastric B cell lymphoma of mucosa-associated lymphoid tissue type (MALT lymphoma), as well as in its preceding lesion, chronic Helicobacter pylori gastritis. Previously we reported that glycans on HEV-like vessels in the latter lesion served as L-selectin ligands, although their function is unclear. We have investigated sialyl Lewis X (sLeX)-related glycoepitopes and found that MECA-79(-) /HECA-452(+) /NCC-ST-439(+) HEV-like vessels preferentially mark gastric MALT lymphoma compared to chronic H. pylori gastritis. We then constructed CHO cell lines expressing potential MECA-79(-) /HECA-452(+) /NCC-ST-439(+) glycans, as well as other sLeX-type glycans, on CD34 and evaluated L-selectin binding to those cells, using L-selectin-IgM chimera binding and lymphocyte adhesion assays. L-selectin-IgM chimeras bound to CHO cells expressing 6-sulpho-sLeX attached to core 2-branched O-glycans with or without 6-sulpho-sLeX attached to extended core 1 O-glycans, but only marginally to other CHO cell lines. By contrast, CHO cells expressing 6-sulpho-sLeX attached to extended core 1 and/or core 2-branched O-glycans, as well as non-sulphated sLeX attached to core 2-branched O-glycans, showed substantial lymphocyte binding, while binding was negligible on lines expressing 6-sulpho- and non-sulphated sLeX attached to N-glycans and non-sulphated sLeX attached to extended core 1 O-glycans. These results indicate that MECA-79(-) /HECA-452(+) /NCC-ST-439(+) glycans, specifically, 6-sulpho- and non-sulphated sLeXs attached to core 2-branched O-glycans, expressed on HEV-like vessels in gastric MALT lymphoma function as L-selectin ligands and likely contribute to H. pylori-specific T cell recruitment in the progression of gastric MALT lymphoma.

Colonic sarcoidosis presenting multiple submucosal tumor-like lesions.

Here, we describe a case of colonic sarcoidosis that developed over a 7-year period of observation of intrathoracic sarcoidosis. The patient was asymptomatic, but colonoscopy showed multiple elevated lesions mimicking submucosal tumors in several areas of the colon. The specimens obtained by biopsy showed noncaseating granuloma, suggesting sarcoidosis. The observations in the present case indicate that colonic involvement should be considered in patients with sarcoidosis. Furthermore, the macroscopic appearance of multiple submucosal tumor-like lesions in colonic sarcoidosis is extremely rare.

GlcNAc6ST-1-mediated decoration of MAdCAM-1 protein with L-selectin ligand carbohydrates directs disease activity of ulcerative colitis.

BACKGROUND: A diffuse lymphocyte infiltrate is 1 of the characteristic features of ulcerative colitis (UC). Such lymphocyte recruitment requires lymphocyte rolling mediated by L-selectin ligand carbohydrates (6-sulfo sialyl Lewis X-capped O-glycans) and/or mucosal addressin cell adhesion molecule 1 (MAdCAM-1) expressed on high endothelial venule (HEV)-like vessels. The present study was undertaken to elucidate the role of MAdCAM-1 posttranslationally modified ("decorated") with L-selectin ligand carbohydrates in UC pathogenesis and consequent clinical outcomes. METHODS: Biopsy specimens composed of active and remission phases of UC as well as normal colonic mucosa were immunostained for CD34, MAdCAM-1, and MECA-79, and the immunostained sections were quantitatively analyzed. Reverse-transcriptase polymerase chain reaction (RT-PCR) was carried out to evaluate transcripts of MAdCAM-1 and N-acetylglucosamine-6-O-sulfotransferases (GlcNAc6STs). CHO and Lec2 cells transfected with CD34 and MAdCAM-1 together with enzymes involved in L-selectin ligand carbohydrate biosynthesis were analyzed by immunofluorescence, FACS, and Western blotting to characterize the biochemical properties of GlcNAc6STs. RESULTS: The number of MAdCAM-1(+) vessels was increased in UC, with no significant difference between active and remission phases. An increased ratio of MECA-79(+) to MAdCAM-1(+) vessels with preferential GlcNAc6ST-1 transcripts was observed in the active phase of UC compared to the remission phase. MAdCAM-1 protein was colocalized with L-selectin ligand carbohydrates at the luminal surface of HEV-like vessels in situ. GlcNAc6ST-1 preferentially utilizes MAdCAM-1 as a scaffold protein for GlcNAc-6-O-sulfation in L-selectin ligand carbohydrate biosynthesis. CONCLUSIONS: UC disease activity is not regulated by expression of MAdCAM-1 protein itself, but rather by GlcNAc6ST-1-mediated decoration of MAdCAM-1 protein with L-selectin ligand carbohydrates.

Preferential induction of peripheral lymph node addressin on high endothelial venule-like vessels in the active phase of ulcerative colitis.

OBJECTIVES: In the colonic mucosa with ulcerative colitis (UC), it has been suggested that L-selectin-peripheral lymph node addressin (PNAd) interaction plays a role in lymphocyte recruitment, which requires PNAd induction on high endothelial venule (HEV)-like vessels. The present study was undertaken to elucidate how these HEV-like vessels participate in the pathogenesis of UC and also to determine whether the presence of such vessels is correlated with clinical outcomes. METHODS: Biopsy specimens composed of active (N = 32) and remission (N = 12) phases of UC were subjected to immunohistochemistry for CD34, MECA-79, and HECA-452, and the immunostained sections were quantitatively analyzed. An in vitro binding assay with L-selectin*IgM chimeric protein was carried out to determine whether PNAd on HEV-like vessels formed in UC functions as an L-selectin ligand. RT-PCR was carried out to determine which enzyme is upregulated for PNAd biosynthesis on HEV-like vessels induced in the active phase of UC. Triple immunostaining for MECA-79 together with CD3 and CD20/CD79alpha, CD4 and CD8, or CXCR3 and ST2L was carried out to determine which lymphocyte population closely associates with these vessels. RESULTS: PNAd-expressing HEV-like vessels were preferentially induced in the active phase of UC with increased transcription of the gene encoding N-acetylglucosamine-6-O-sulfotransferase (GlcNAc6ST)-1, which directs expression of the MECA-79 epitope. Moreover, T cells, particularly CD4(+) T cells, were more closely associated with these HEV-like vessels than B cells. CONCLUSIONS: T-cell recruitment via PNAd-expressing HEV-like vessels induced by expression of GlcNAc6ST-1 may play a role in UC pathogenesis.

t(8;21;14)(q22;q22;q24) is a novel variant of t(8;21) with chimeric transcripts of AML1-ETO in acute myelogenous leukemia.

We report a male patient with acute myelogenous leukemia (AML; French-American-British M2) associated with AML1-ETO. Cytogenetic studies showed a complex karyotype including a novel translocation (8;21;14)(q22;q22;q24) in all analyzed cells. This three-way translocation was confirmed with spectral karyotyping. Reverse transcription-polymerase chain reaction analysis for AML1-ETO chimeric transcripts showed the presence of the fusion product with the expected size. Translocation (8;21;14)(q22;q22;q24) is a novel variant of t(8;21)(q22;q22), possibly having a common molecular pathogenetic mechanism.