Bone marrow-derived stromal cells are associated with gastric cancer progression.

BACKGROUND: The aim of this study was to clarify the role of bone marrow-derived stromal cells (BM-SCs) expressing CD271 in the development of gastric cancer. METHODS: The effect of human BM-SCs on the proliferation and motility of six gastric cancer cell lines, OCUM-2M, OCUM-2MD3, OCUM-12, KATO-III, NUGC-3, and MKN-74, was examined. CD271 expression levels in BM-SCs were analysed by flow cytometry. We also generated a gastric tumour model by orthotopic inoculation of OCUM-2MLN cells in mice that had received transplantation of bone marrow from the CAG-EGFP mice. The correlation between the clinicopathological features of 279 primary gastric carcinomas and CD271 expression in tumour stroma was examined by immunohistochemistry. RESULTS: Numerous BM-SCs infiltrated the gastric tumour microenvironment; CD271 expression was found in ∼25% of BM-SCs. Conditioned medium from BM-SCs significantly increased the proliferation of gastric cancer cell lines. Furthermore, conditioned medium from gastric cancer cells significantly increased the number of BM-SCs, whereas migration of OCUM-12 and NUGC-3 cells was significantly increased by conditioned medium from BM-SCs. CD271 expression in stromal cells was significantly associated with macroscopic type-4 cancers, diffuse-type tumours, and tumour invasion depth. The overall survival of patients (n=279) with CD271-positive stromal cells was significantly worse compared with that of patients with CD271-negative stromal cells. This is the first report of the significance of BM-SCs in gastric cancer progression. CONCLUSIONS: Bone marrow-derived stromal cells might have an important role in gastric cancer progression, and CD271-positive BM-SCs might be a useful prognostic factor for gastric cancer patients.

Assessment of secondary attack rate and effectiveness of antiviral prophylaxis among household contacts in an influenza A(H1N1)v outbreak in Kobe, Japan, May-June 2009.

This report describes the assessment of the secondary attack rate (SAR) and the effectiveness of post-exposure antiviral prophylaxis among household contacts in the first domestic outbreak of a novel influenza A(H1N1)v between mid-May and early June 2009 in Kobe city, Japan. Of the 293 subjects, 14 (4.8%) household contacts met the case definition and most secondary cases were probably infected around the time of symptom onset date of the respective index case. The SAR among household contacts who did not receive prophylaxis was 7.6%, similar to the rate of seasonal influenza, and the attack rate in siblings was significantly higher than that in parents. We conclude that it is important to establish routine infection control measures for households in order to prevent the spread of the virus among household contacts and, possibly, to the community. We could not conclude whether antiviral prophylaxis was effective or not. However, among close contacts with underlying disease who received prophylaxis, nobody developed a severe form of the disease.

Epidemiology of influenza A(H1N1)v virus infection in Japan, May-June 2009.

Between 9 May and 4 June 2009, a total of 401 laboratory-confirmed cases of influenza A(H1N1)v virus were reported in Japan, from 16 of the 47 Japanese prefectures. The two areas most affected were Osaka prefecture and Kobe city where outbreaks in high schools occurred leading to school closures. To date all cases have had symptoms consistent with seasonal influenza and no severe or fatal cases have been reported.

Influence of Helicobacter pylori eradication on reflux esophagitis in Japanese patients.

The relationship between Helicobacter pylori eradication and reflux esophagitis is controversial. We analyzed the development of reflux esophagitis and the change in the grade of pre-existing reflux esophagitis after eradication. Enrolled were 559 Japanese patients who received eradication therapy for H. pylori. The grade of reflux esophagitis by endoscopy before and after therapy was evaluated retrospectively. No esophagitis was present before eradication in 526 patients. H. pylori was and was not eradicated in 429 and 97, respectively. Reflux esophagitis developed in 40 of the eradication group and in three of the treatment failure group, with prevalence higher with successful eradication (P = 0.04). Successful eradication and hiatus hernia were significant risk factors for reflux esophagitis development. Twenty-seven of 33 patients with pre-existing reflux esophagitis had successful eradication and six treatment failure. The reflux esophagitis grade worsened in two (Los Angeles classification from A to B) and improved in 14 patients after eradication. With treatment failure, reflux esophagitis worsened in none and improved in three patients. There showed no significant change in the grade of pre-existing reflux esophagitis after H. pylori eradication but the sample size was too small to evaluate the difference. In conclusion, the eradication of H. pylori increases the prevalence of reflux esophagitis, and hiatus hernia was a significant risk factor for the development of reflux esophagitis.

Helicobacter pylori eradication reduced the incidence of gastric cancer, especially of the intestinal type.

BACKGROUND: Although Helicobacter pylori infection is closely associated with gastric cancer development, follow-up studies after H. pylori eradication are still scarce. AIM: To clarify the cancer preventive effect of H. pylori eradication, with special attention to differences in effect according to histology. METHODS: Patients who underwent H. pylori eradication therapy and were followed-up endoscopically for at least 1 year were analysed. The incidence of gastric cancer and factors associated with cancer development were investigated. RESULTS: A total of 1807 patients were enrolled. Six of 1519 H. pylori eradicated and five of 288 persistent subjects developed gastric cancer. Four of the eradicated subjects developed the intestinal type and two the diffuse type, while four of the persistent subjects developed the intestinal type and one the diffuse type. Kaplan-Meier analysis indicated a significantly lower incidence in eradicated patients than in persistent patients. The incidence of intestinal type was significantly lower than in eradicated patients, while the diffuse type could not be evaluated because of the low incidence. CONCLUSIONS: Helicobacter pylori-eradicated patients had a reduced incidence of gastric cancer compared with H. pylori-persistent patients, particularly the intestinal type, suggesting that H. pylori is strongly associated with intestinal-type gastric cancer.

Increased myocardial Rab GTPase expression: a consequence and cause of cardiomyopathy.

The Ras-like Rab GTPases regulate vesicle transport in endocytosis and exocytosis. We found that cardiac Rabs1, 4, and 6 are upregulated in a dilated cardiomyopathy model overexpressing beta(2)-adrenergic receptors. To determine if increased Rab GTPase expression can contribute to cardiomyopathy, we transgenically overexpressed in mouse hearts prototypical Rab1a, the small G protein that regulates vesicle transport from endoplasmic reticulum to and through Golgi. In multiple independent mouse lines, Rab1a overexpression caused cardiac hypertrophy that progressed in a time- and transgene dose-dependent manner to heart failure. Isolated cardiac myocytes were hypertrophied and exhibited contractile depression with impaired calcium reuptake. Ultrastructural analysis revealed enlarged Golgi stacks and increased transitional vesicles in ventricular myocytes, with increased secretory atrial natriuretic peptide granules and degenerative myelin figures in atrial myocytes; immunogold studies localized Rab1a to these abnormal vesicular structures. A survey of hypertrophy signaling molecules revealed increased protein kinase C (PKC) alpha and delta, and confocal microscopy showed abnormal subcellular distribution of PKCalpha in Rab1a transgenics. These results indicate that increased expression of Rab1 GTPase in myocardium distorts subcellular localization of proteins and is sufficient to cause cardiac hypertrophy and failure.

Overexpression of EC-SOD suppresses endothelial-cell-mediated LDL oxidation.

Reactive oxygen species have been proposed to play important roles in atherosclerosis. To investigate the protective role of extracellular superoxide dismutase (EC-SOD), its inhibition of endothelial-cell-mediated LDL oxidation was examined. We constructed the recombinant adenovirus AxCAEC-SOD expressing human EC-SOD by CAG promoter. Infection of endothelial cells with AxCAEC-SOD resulted in EC-SOD protein secretion in a dose-dependent manner and a decrease of endothelial-cell-derived superoxide production. Moreover, it was proven to coexist with heparan sulfate by immunohistochemical staining. Endothelial-cell-mediated LDL oxidation enhanced by ferric-sodium EDTA was inhibited by 47% in TBARS formation by AxCAEC-SOD infection. In agarose gel electrophoresis, AxCAEC-SOD decreased the negative charge of oxidized LDL by 50% and suppressed fragmentation of apolipoprotein B. These results suggested that human EC-SOD localized in the extracellular space and reduced endothelial-cell-mediated LDL oxidation. In subendothelial space, EC-SOD bound on heparan sulfate might suppress LDL oxidation through reduction of superoxide anion.

Divergent transcriptional responses to independent genetic causes of cardiac hypertrophy.

To define molecular mechanisms of cardiac hypertrophy, genes whose expression was perturbed by any of four different transgenic mouse hypertrophy models [protein kinase C-epsilon activation peptide (PsiepsilonRACK), calsequestrin (CSQ), calcineurin (CN), and Galpha(q)] were compared by DNA microarray analyses using the approximately 8,800 genes present on the Incyte mouse GEM1. The total numbers of regulated genes (tens to hundreds) correlated with phenotypic severity of the model (Galpha(q) > CN > CSQ > PsiepsilonRACK), but demonstrated that no single gene was consistently upregulated. Of the three models exhibiting pathological hypertrophy, only atrial natriuretic peptide was consistently upregulated, suggesting that transcriptional alterations are highly specific to individual genetic causes of hypertrophy. However, hierarchical-tree and K-means clustering analyses revealed that subsets of the upregulated genes did exhibit coordinate regulatory patterns that were unique or overlapping across the different hypertrophy models. One striking set consisted of apoptotic genes uniquely regulated in the apoptosis-prone Galpha(q) model. Thus, rather than identifying a single common hypertrophic cardiomyopathy gene program, these data suggest that extensive groups of genes may be useful for the prediction of specific underlying genetic determinants and condition-specific therapeutic approaches.

Homocysteine inhibits angiogenesis in vitro and in vivo.

Homocysteine has been reported to inhibit endothelial cell proliferation, which is closely related to angiogenesis. However, the relationship between homocysteine and angiogenesis is unknown. To clarify whether homocysteine would inhibit angiogenesis in vitro and in vivo, we examined the effect of homocysteine on tube formation by bovine aortic endothelial cells (BAECs) and by human microvessel endothelial cell-1 (HMEC-1) in vitro, and on angiogenesis in vivo using the chorioallantoic membrane (CAM) assay, as well as on BAEC proliferation and migration. Homocysteine, but not cysteine, inhibited BAEC proliferation, migration, and tube formation in a dose-dependent manner at concentrations from 0 to 10 mM. Homocysteine also inhibited tube formation by HMEC-1s. In these assay, 50% inhibition was induced by about 1 mM homocysteine. In the in vivo CAM assay, 0, 10, 100, 500, and 1000 microgram homocysteine induced an avascular zone by 0, 0, 16.7, 53.3 and 76.5%, respectively, also showing a dose-dependent effect. It was suggested that homocysteine inhibited angiogenesis by preventing proliferation and migration of endothelial cells.

Epsilon protein kinase C in pathological myocardial hypertrophy. Analysis by combined transgenic expression of translocation modifiers and Galphaq.

The epsilon isoform of protein kinase C (PKC) has a critical cardiotrophic function in normal postnatal developing heart as demonstrated by cardiac-specific transgenic expression of epsilonPKC-selective translocation inhibitor (epsilonV1) and activator (psiepsilonRACK) peptides (Mochly-Rosen, D., Wu, G., Hahn, H., Osinska, H., Liron, T., Lorenz, J. N., Robbins, J., and Dorn, G. W., II (2000) Circ. Res. 86, 1173-1179). To define the role of epsilonPKC signaling in pathological myocardial hypertrophy, epsilonV1 or psiepsilonRACK were co-expressed in mouse hearts with Galpha(q), a PKC-linked hypertrophy signal transducer. Compared with Galpha(q) overexpression alone, co-expression of psiepsilonRACK with Galpha(q) increased epsilonPKC particulate partitioning by 30 +/- 2%, whereas co-expression of epsilonV1 with Galpha(q) reduced particulate-associated epsilonPKC by 22 +/- 1%. Facilitation of epsilonPKC translocation by psiepsilonRACK in Galpha(q) mice improved cardiac contractile function measured as left ventricular fractional shortening (30 +/- 3% Galpha(q) versus 43 +/- 2% psiepsilonRACK/Galpha(q), p < 0.05). Conversely, inhibition of epsilonPKC by epsilonV1 modified the Galpha(q) nonfailing hypertrophy phenotype to that of a lethal dilated cardiomyopathy. These opposing effects of epsilonPKC translocation activation and inhibition in Galpha(q) hypertrophy indicate that epsilonPKC signaling is a compensatory event in myocardial hypertrophy, rather than a pathological event, and support the possible therapeutic efficacy of selective epsilonPKC translocation enhancement in cardiac insufficiency.

Changes in the heparin affinity of extracellular-superoxide dismutase in patients with coronary artery atherosclerosis.

Extracellular-superoxide dismutase [EC 1.15.1.1] (EC-SOD) is a secretory glycoprotein with high affinity for heparin. This enzyme locates in blood vessel walls at a high enough level to suppress oxidative stress under normal conditions. EC-SOD is the major SOD isozyme in plasma, anchored to heparan sulfate proteoglycans in the glycocalyx of endothelial cell surfaces. Plasma EC-SOD is heterogeneous in heparin affinity and can be divided into five fractions, I to V, by heparin-HPLC. It has been suggested that EC-SOD form V is the primary form synthesized in the body and that EC-SOD forms with reduced heparin affinity are the result of proteolytic truncation of the C-terminal end of EC-SOD form V which is responsible for the binding with heparin. Recently, we reported that only plasma EC-SOD form V, with the highest heparin affinity, was increased by intravenous injection of heparin. The heparin affinity of plasma EC-SOD in patients with coronary atherosclerosis (CA+ patients) was compared in this study. The increase of plasma EC-SOD form V after heparin injection in CA+ patients was significantly less than that in subjects without evidence of stenosis in their major coronary arteries (CA- subjects). On the other hand, in CA+ patients, EC-SOD forms I to III, with low heparin affinity, were significantly increased compared to those in CA- subjects. EC-SOD in plasma apparently forms an equilibrium between the plasma phase and endothelial cell surface, and EC-SOD on the endothelial cell surface contributes to protecting the vessel wall against oxidative stress. These findings suggest that the quantitative and qualitative changes of EC-SOD, i.e., the decrease of bound EC-SOD on the endothelial cell surface, might suppress the defense systems against oxidative stress, which causes in part the development of coronary artery atherosclerosis.

Spectroscopic analysis of the cytoagglutinating activity of abrin-b isolated from Abrus precatorius seeds against leukemic cells.

The cytoagglutinating activity of abrin-b, a toxic lectin isolated from Abrus precatorius seeds, against cultured cell strains derived from acute lymphoblast leukemia (ALL) was investigated by visible (VIS) spectroscopy. Upon addition of abrin-b, the turbidity at 600 nm of cell suspension decreased and this change could be recorded as the cytoagglutination curve. From this curve, the cytoagglutination velocity (CV) and cytoagglutination intensity (CI) of each cell strain was measured. Each cell strain showed the respective CV and CI values and the cell strains derived from the T cell line were strongly agglutinated by abrin-b compared with those derived from the B cell line. Further, it has become apparent that the cytoagglutinating activity increased with an increase in the order of the differentiation of cell strains.

The comparative diagnostic value of dobutamine stress echocardiography and thallium stress tomography for detecting restenosis after coronary angioplasty.

The noninvasive detection of restenosis is clinically important for the subsequent management of patients in whom percutaneous transluminal coronary angioplasty (PTCA) has been performed. The aim of this study was to compare the diagnostic value of dobutamine stress echocardiography (DSE) and stress 201Tl single-photon emission computed tomography (SPECT) for detecting restenosis after PTCA. Fifty-three consecutive patients referred for the evaluation of possible restenosis or whom had been scheduled for follow-up study underwent DSE a mean of 5 months after angiographically successful PTCA. Dobutamine was infused incrementally under two-dimensional echocardiographic imaging. The left ventricle was divided into 16 segments and grouped into three coronary vascular territories. Rest, low-dose, and peak-dose images were digitized and displayed in a quad-screen format. Positive findings for restenosis were defined as new or worsened wall motion abnormality at a previously dilated vascular territory. All but one patient underwent SPECT. Positive findings for restenosis were defined as the presence of redistribution. All patients underwent quantitative coronary angiography after two tests. Restenosis was angiographically demonstrated in 23 (43%) of 53 patients and 25 (42) of 59 vessels. The sensitivity of DSE and SPECT for detecting restenosis was 78% and 74%, specificity was 93% and 93%, and accuracy was 87% and 85%, respectively. In a total of 59 vascular regions, DSE was 76% sensitive and 94% specific for detecting individual restenosis. It is concluded that DSE is comparable in diagnostic accuracy to SPECT for detecting restenosis in patients after PTCA.

Multiple metastatic calcifications detected by bone scintigraphy and demonstrated by CT.

Metastatic calcifications according to histopathologic and scintigraphic findings have been well-defined. The authors report a postoperative case of hyperparathyroidism with multiple metastatic calcifications in the lung, kidney, stomach, heart, and vessels that were primarily detected by bone scintigraphy and demonstrated by CT. Tc-99m MDP bone scintigraphy showed a markedly increased accumulation of radioactivity diffusely throughout the lung, left ventricular wall, both kidneys, and the gastric cardia and body. In the lung, plain films showed almost normal lung. CT, however, demonstrated patchy, slightly increased densities in the lung bilaterally. Cardiac CT indicated a considerably increased density of the ventricular myocardium and remarkable calcification in or near the atrioventricular septum or annulus fibrosus. Upper abdominal CT demonstrated increased densities diffusely throughout the gastric mucosa and renal cortex. Only vascular calcifications were depicted by plain films. Using both bone scintigraphy and CT provides accurate information about each lesion and each tissue, allowing precise diagnosis of even a questionable lesion in the early stage of metastatic calcification. Early diagnosis and early therapy offer the best chance for cure or palliative therapy.

Genetic regulation of the development of glomerular sclerotic lesions in the BUF/Mna rat.

BUF/Mna strain rats spontaneously develop renal glomerular sclerotic lesions (RSL) at a nearly 100% incidence, diagnosed by hyperalbuminuria (greater than 500 mg/dl) and glomerular lesions morphologically resembling one type of human focal glomerular sclerosis (FGS). Genetic segregation of RSL development was studied by crossing the BUF/Mna strain with two other rat strains, WKY/NCrj and ACI/NMs, which were free of RSL. Two autosomal recessive genes in the BUF/Mna rats were found to determine the susceptibility to RSL in both combinations of crosses.

New thymocyte growth factor from thymic epithelial cell line.

Three polypeptide fractions were separated from the culture supernatant of a thymic epithelial cell line, TAD3, by high-pressure liquid chromatography (HPLC) equipped with gel-filtration column (GFC). One (estimated molecular weight: 10 kD) of the polypeptide fractions possessed the capacity to induce thymocyte proliferation. The sensitive cells for the growth factor in the fraction seem to be immature thymocytes which exist in the outer-cortical or the subcapsular area of thymic lobule. Furthermore, the mechanism to proliferate the thymocytes appears to differ from that of other cytokines. Thus, the fraction might possibly contain a previously unidentified thymocyte growth factor.

Protection by thymosin fraction 5 from streptozotocin-induced diabetes in mice.

Protection by thymosin fraction 5 (TF5) from subdiabetogenic-dose streptozotocin (STZ)-induced type I diabetes in CD-1 mice was investigated. Mice which received multiple subdiabetogenic-dose (35 mg/kg) injections of STZ became hyperglycemia within two weeks. Hyperglycemia was also induced in those treated with low dose of TF5 (0.01 mg/day) in addition to STZ, though it was somewhat mild. In contrast, animals given STZ plus high dose of TF5 (0.1 mg/day) remained normoglycemic throughout the whole observation period (within 4 weeks). In the pancreatic islets from these animals, histologically, the well-granulated beta cells were observed and the infiltration of lymphoid cells was absent or mild. These results suggest that the administration of TF5 prevents the induction of insulitis and hyperglycemia in the subdiabetogenic-dose STZ-treated mice.