Characterization of the immune escape phenotype of human gastric cancers with and without high-frequency microsatellite instability

Gastric cancers with and without high-frequency microsatellite instability (MSI-H) represent distinctive pathways of carcinogenesis. The aim of this study was to clarify if human leukocyte antigen (HLA) class I antigen subunits and antigen processing machinery (APM) components are differentially downregulated in these two groups of tumours. Using reverse transcription PCR (RT-PCR), loss of heterozygosity (LOH) analysis, methylation-specific PCR (MSP), DNA sequencing, immunohistochemistry, and flow cytometry, we analysed expression and/or alteration of HLA class I antigen subunits and APM components, including low molecular weight polypeptide proteasome subunit (LMP)2, LMP7, LMP10, transporter associated with antigen processing (TAP)1, TAP2, tapasin, proteasome activator (PA) 28alpha, and PA28beta in two stage-matched panels of 30 MSI-H and 30 microsatellite stable (MSS) gastric cancers. Mutations at coding microsatellites (cMS) located within beta2-microglobulin (beta2m) and genes encoding APM components, including endoplasmic reticulum (ER) chaperone protein genes, such as calnexin, SEC63, SEC31, and P4HB (p55), were also analysed. HLA class Ia transcripts were totally downregulated in 18.3% of cancer cases. Locus-specific downexpression of HLA-A, -B, and -C was detected in 41.7%, 45.0%, and 31.7% of cases. Loss of HLA-A was significantly more frequent in MSI-H cancers. The LOH ratios of the HLA-A, -B, and -C loci microsatellite markers were relatively low: 5/32 (15.6%) for D6S306, 4/32 (12.5%) for D6S258, 4/33 (12.1%) for D6S273, and 4/30 (13.3%) for D6S1666. Methylation of HLA-A, -B, and -C was detected in 38.3%, 40.0%, and 28.3% of cases. A significant association between methylation and reduction in expression was observed in gastric cancer tissues. Mutations at cMS of beta2m and APM components were detected in 3.3-46.7% of MSI-H cancers but in none of MSS cancers. These data show that gastric cancers have various defects in HLA class I antigen subunits and APM components and that the MSI phenotype is associated with frequent HLA-A inactivation and frameshift mutations of the beta2m and APM genes.

Intake of purple sweet potato beverage affects on serum hepatic biomarker levels of healthy adult men with borderline hepatitis

OBJECTIVE

To examine the effect of purple sweet potato (PSP) beverage rich in acylated anthocyanins on serum hepatic biomarkers in healthy Japanese men.

DESIGN

A randomized, double-blind, placebo-controlled, parallel study.

SETTING

Kumamoto in Japan.

SUBJECTS

Healthy adult men (30-60 years) with borderline hepatitis who had one or more of serum gamma-glutamyl transferase (GGT), aspertate aminotransferase (AST) and alanine aminotransferase (ALT) levels over normal ranges, and who were negative for hepatitis virus were openly recruited by an advertisement. Of the 48 persons enrolled, 38 (mean age 43.0 years (30-54 years)) completed the study.

METHODS

The subjects were randomly assigned to the PSP group and the placebo group. During the 8-week intervention, the subjects in the PSP group consumed two bottles of the PSP beverage with acylated anthocyanins (200.3 mg anthocyanins per 125 ml per bottle) per day, and the subjects in the placebo group, two bottles of a placebo beverage (1.7 mg anthocyanins per 125 ml per bottle). All of the data measured were analyzed by two-way repeated measures analysis of variance (ANOVA) with groups and times. The data of the hepatic markers were analyzed using the Dunnett multiple comparison among the time points and t-test between groups at the same time point. Two-sided P<0.05 were defined as the level of significance.

RESULTS

Serum GGT, AST and ALT levels showed interactions (P<0.05) between the beverage groups and time; the others were not affected. The PSP beverage group showed lower hepatic marker levels than the placebo group during the ingestion period, particularly the GGT level (-14.1 IU/l, 95% Confidence intervel (CI) -25.4 to -2.7, P=0.017 at 2 weeks; -16.8 IU/l, 95% CI -36.2 to 2.5, P=0.081 at 4 weeks; -26.7 IU/l, 95% CI -47.6 to -5.7, P=0.014 at 6 weeks and -27.9 IU/l, 95% CI -49.9 to -5.9; P=0.014 at 8 weeks). No correlation between alcohol consumption and each hepatic biomarker level before and after the ingestion was observed.

CONCLUSION

The intake of the PSP beverage significantly decreased the serum levels of hepatic biomarkers, particularly the GGT level, in healthy men with borderline hepatitis.

K-ras mutation in the endometrium of tamoxifen-treated breast cancer patients, with a comparison of tamoxifen and toremifene

The putative presence of a mutation in codon 12 of the K-ras gene was investigated in the endometrium of tamoxifen (TAM) and toremifene (TOR)-treated breast cancer patients. DNA was extracted from fresh cytologic samples of the endometrium in 86 TAM and 21 TOR-treated breast cancer patients. Mutations were detected by enriched PCR and an enzyme-linked mini-sequence assay (ELMA). K-ras mutation was found in 35 TAM-treated endometrial samples, and in only one TOR-treated endometrium (P<0.003). In 24 premenopausal patients, K-ras mutation was found in seven (43.8%) of 16 patients with less than 47 months of TAM treatment, while none was found in eight patients with more than 48 months of TAM treatment (P<0.03). In 62 postmenopausal-amenorrheic patients, K-ras mutation was found in three (15.8%) of 19 patients with less than 23 months of TAM treatment, while it was found in 16 (61.5%) of 26 patients with 24–47 months of TAM treatment and nine (52.9%) of 17 patients with more than 48 months of TAM treatment (P=0.002). The presence of K-ras mutation is significantly influenced by the duration of TAM treatment and menstrual status of the patients. TOR may have a lower potential genotoxicity than TAM.

Renal clearance of glycolaldehyde- and methylglyoxal-modified proteins in mice is mediated by mesangial cells through a class A scavenger receptor (SR-A)

AIMS/HYPOTHESIS

Glomerular mesangial expansion is a characteristic feature of diabetic nephropathy, and the accumulation of AGE in the mesangial lesion has been implicated as one of its potential causes. However, the route for the AGE accumulation in mesangial lesions in diabetic patients is poorly established.

METHODS

Glycolaldehyde-modified BSA (GA-BSA) and methylglyoxal-modified BSA (MG-BSA) were prepared as model AGE proteins, and their in vivo plasma clearance was examined in mice, and renal uptake by in vitro studies with isolated renal mesangial cells.

RESULTS

Both (111)In-GA-BSA and (111)In-MG-BSA were rapidly cleared from the circulation mainly by both the liver and kidney. Immunohistochemical studies with an anti-GA-BSA antibody demonstrated that intravenously injected GA-BSA accumulated in mesangial cells, suggesting that such cells play an important role in the renal clearance of circulating AGE proteins. Binding experiments at 4 degrees C using mesangial cells isolated from mice showed that (125)I-GA-BSA and (125)I-MG-BSA exhibited specific and saturable binding. Upon incubation at 37 degrees C, (125)I-GA-BSA and (125)I-MG-BSA underwent endocytic degradation by these cells. The binding of the ligands to these cells was inhibited by several ligands for scavenger receptors. The endocytic degradation of GA-BSA by mesangial cells from class A scavenger receptor (SR-A) knock-out mice was reduced by 80% when compared with that of wild-type cells. The glomerular accumulation of GA-BSA after its intravenous administration was attenuated in SR-A knock-out mice, as evidenced by immunohistochemical observations.

CONCLUSIONS/INTERPRETATION

These results raise the possibility that circulating AGE-modified proteins are subjected to renal clearance by mesangial cells, mainly via SR-A. This pathway may contribute to the pathogenesis of AGE-induced diabetic nephropathy.

Near-field optical microscope observation of dye-containing nano-domains

A novel method for forming dye-containing nano-domains in thin films using a polymer alloy system has been developed. The polymer alloy system (PS-b-PMMA), which consists of polystyrene (PS) and polymethyl methacrylate (PMMA), forms microphase separation in thin films. The film was treated using a previously reported technique under vacuum conditions, and an organic dye was selectively dispersed into the PS. Selective association of the dye (diarylethene; cis-1, 2-dicyano-1, 2-bis (2,4,5-trimethyl-3-thienyl) ethene) with the PS nano-domains was then observed, with both transmission electron microscopy and scanning near-field optical microscopy with an absorption spectrum.

Application of monoclonal antibody libraries for the measurement of glycation adducts

Immunological approaches have been used to demonstrate the presence of advanced glycation end-products (AGEs) in several human and experimental animal tissues. We previously prepared polyclonal and monoclonal anti-AGE antibodies by immunizing AGE-modified proteins such as BSA and RNase. Although these antibodies contributed to demonstrate the presence of AGE-modified protein in vivo, the epitope structure of these antibodies had not been identified. We subsequently prepared several antibodies against AGE structures such as pentosidine, pyrraline, 3-deoxyglucosone imidazolone and N∊-(carboxyethyl)lysine by immunizing single AGE structures. These structure-specific antibodies have greatly helped broaden our understanding of AGE structures in aging and age-enhanced disease process. Monoclonal anti-AGE antibody is also used for the identification of major AGE structures in some pathological tissues, such as human atherosclerosis lesions. Based on the strategy, we successfully identified a novel AGE structure named glycolaldehyde-pyridine, which is the major antigenic AGE derived from glycolaldehyde. Therefore a monoclonal antibody library for AGE structures has served an important role in the elucidation of the biological significance of AGE.

Mechanisms involved in the stimulatory effect of advanced glycation end products on growth of rat aortic smooth muscle cells

Hyperglycemia is an important cause of accelerated atherosclerosis in diabetic patients. We examined the effect of hyperglycemia and advanced glycation end products (AGE) on proliferation of rat aortic smooth muscle cells (SMC) in culture; in vivo, this event is believed to contribute importantly to atherogenesis in diabetes mellitus. Glucose itself dose-dependently inhibited thymidine uptake by SMC, but AGE increased thymidine uptake, suggesting that SMC proliferation is accelerated by AGE. To examine possible mechanisms for this effect, we studied nuclear factor-kappa B (NF-kappaB) activation and the tyrosine phosphorylation pathway; AGE stimulated NF-kappaB activity, but phosphorylation of the platelet-derived growth factor (PDGF) receptor was unchanged. In Chinese hamster ovary (CHO) cells overexpressing galectin-3, an AGE receptor related to atherosclerosis, AGE increased thymidine uptake. This suggests SMC proliferation is enhanced by AGE via galectin-3. As pathways involving AGE-galectin-3 interaction thus may be involved in macroangiopathy, AGE appears to be important to the role of SMC in accelerated atherosclerosis associated with diabetes mellitus.

Scavenger receptors for oxidized and glycated proteins

Our present knowledge on chemically modified proteins and their receptor systems is originated from a proposal by Goldstein and Brown in 1979 for the receptor for acetylated LDL which is involved in foam cell formation, one of critical steps in atherogenesis. Subsequent extensive studies using oxidized LDL (OxLDL) as a representative ligand disclosed at least 11 different scavenger receptors which are collectively categorized as "scavenger receptor family". Advanced glycation endproducts (AGE) and their receptor systems have been studied independently until recent findings that AGE-proteins are also recognized as active ligands by scavenger receptors including class A scavenger receptor (SR-A), class B scavenger receptors such as CD36 and SR-BI, type D scavenger receptor (LOX-1) and FEEL-1/FEEL-2. Three messages can be summarized from these experiments; (i) endocytic uptake of OxLDL and AGE-proteins by macrophages or macrophage-derived cells is mainly mediated by SR-A and CD36, which is an important step for foam cell formation in the early stage of atherosclerosis, (ii) selective uptake of cholesteryl esters of high density lipoprotein (HDL) mediated by SR-BI is inhibited by AGE-proteins, suggesting a potential pathological role of AGE in a HDL-mediated reverse cholesterol transport system, (iii) a novel scavenger receptor is involved in hepatic clearance of plasma OxLDL and AGE-proteins.

Recent trends and prospects in world population growth

"This article assesses the causes of the stagnation in the declining trend in world population growth rates over the past decade. Three major factors have been identified as contributing to the stagnation: age structure, fertility trends in India and China, and the fact that although the number of developing countries with sustained declines in fertility levels rose sharply in the late 1960s and 1970s, it dropped off dramatically in the 1980s. Prospects for the growth rate in the 1990s favour a decline, owing to changes in the age structure and indications that China and India have resumed their fertility declines. However, there remain some populous developing countries that continue to have high levels of fertility. Fertility trends in those countries will have a certain influence on the world's growth rate."

Assessing the effects of mortality reduction on population ageing

"This article presents a new method for decomposing age distribution changes into changes in the number of births and changes in age-specific rates of mortality and migration. The method is developed on the basis of the equation for the age-specific growth rate proposed by Horiuchi and Preston (1988). Using this method, it is shown that the increase in the proportion of women in Japan during 1970-1980 is mainly due to the reduction of mortality, particularly at old ages. The results lend support to the proposed idea that the pattern of age structure changes in developed countries is now shifting from fertility-dominated to mortality-dominated ageing." This is a revised version of a paper originally presented at the 1989 Annual Meeting of the Population Association of America.

Advanced glycation end products impair the scavenger function of rat hepatic sinusoidal endothelial cells

AIMS/HYPOTHESIS

We have previously reported that advanced glycation end products are eliminated from the circulation mainly by scavenger receptor-mediated uptake in hepatic sinusoidal endothelial cells. Our experiments showed that the degradation of AGE-modified protein after endocytosis in hepatic sinusoidal endothelial cells occurs slowly compared with that of other scavenger receptor ligands. The aim of this study was to investigate further the mechanism whereby AGE-modified protein affects the important scavenger function of hepatic sinusoidal endothelial cells.

METHODS

Primary cultures of hepatic sinusoidal endothelial cells were pre-incubated with unlabelled ligand, unbound ligand was washed off, and the endocytic capacity was measured by addition of radiolabelled ligand, and immune electron microscopy.

RESULTS

Pre-incubation with unlabelled AGE-modified bovine serum albumin reduced subsequent endocytosis of radiolabelled scavenger receptor ligands AGE-modified bovine serum albumin, formaldehyde-treated serum albumin, oxidized low density lipoprotein and acetylated low density lipoprotein by 50, 56, 32 and 20%, respectively. Non-scavenger receptor-mediated endocytosis was not affected by pre-exposure to AGE-modified protein. Pre-incubation with a number of non-AGE-ligands did not affect subsequent endocytosis via any of the major endocytosis receptors in hepatic sinusoidal endothelial cells. Incubation in fresh medium for 6 h after pre-exposure to AGE-modified protein almost completely restored normal scavenger receptor-mediated endocytic activity. Quantitative immune electron microscopy showed that the amount of a newly described scavenger receptor for AGE-modified protein is reduced after pre-incubation with AGE-modified protein. Subcellular fractionation showed that pre-incubation with AGE-modified protein delays intracellular transport of scavenger receptor ligands.

CONCLUSION/INTERPRETATION

Endocytosis of AGE-modified protein leads to loss of scavenger receptors and delayed intracellular transport in hepatic sinusoidal endothelial cells.

Polytetrafluoroethylene patch sling for type 2 or type 3 stress urinary incontinence

BACKGROUND

Surgical success rates and complications of anti-incontinence surgery were evaluated according to the type of stress incontinence and the type of surgery.

METHODS

From 1989 to 1998, we treated 137 women for stress urinary incontinence with anti-incontinence surgery. Of the 137 patients, 110 had type 2 stress urinary incontinence and 27 had type 3 stress urinary incontinence. Of 110 patients with type 2 stress urinary incontinence, 57 underwent pubovaginal sling procedure and 53 were treated with the Gittes procedure. All of the patients with type 3 stress urinary incontinence underwent the pubovaginal sling procedure.

RESULTS

Cure rates with the pubovaginal sling procedure were 82% in type 2 incontinence and 70% in type 3 incontinence. Cure rates with the Gittes procedure were 56%. The occurrence of de novo urge symptom and pelvic pain was low and bore no relation to either operative method or type of stress incontinence.

CONCLUSIONS

The pubovaginal sling procedure using the polytetrafluoroethylene patch was effective for type 2 or 3 stress urinary incontinence.

CD36, a member of class B scavenger receptor family, is a receptor for advanced glycation end products

Interaction of advanced glycation end products (AGE) with AGE-receptors induces several cellular phenomena relating potentially to diabetic complications. Five AGE-receptors identified so far are RAGE (receptor for AGE), 80 K-H, OST-48, galectin-3, and SR-A (macrophage scavenger receptor type I and II). Since SR-A belongs to the class A scavenger receptor family and the scavenger receptor collectively represents a family of multiligand lipoprotein receptors, it is possible that CD36 belonging to the class B scavenger receptor family (SR-B) can recognize AGE-proteins as a ligand. This was tested in the present study at the cellular level using CHO (Chinese hamster ovary) cells overexpressing human CD36 (CHO-CD36 cells). 125I-AGE-BSA (bovine serum albumin) was endocytosed in a dose-dependent fashion and underwent lysosomal degradation by CHO-CD36 but not wild-type CHO cells. Endocytic uptake of 125I-AGE-BSA by these cells was inhibited 50% by oxidized LDL (Ox-LDL) and 60% by FA6-152, an anti-CD36 antibody inhibiting cellular binding of Ox-LDL. Our results indicate that CD36 expressed by these cells mediates endocytic uptake and subsequent intracellular degradation of AGE-proteins. Because CD36 is one of the major Ox-LDL receptors and is upregulated in macrophage- and smooth muscle cell-derived foam cells in human atherosclerotic lesions, the present results suggest that, like Ox-LDL, AGE-proteins generated in situ are recognized by CD36, which might contribute to the pathogenesis of diabetic macrovascular complications.

Frequent alterations of the beta-catenin and TCF-4 genes, but not of the APC gene, in colon cancers with high-frequency microsatellite instability

High-frequency microsatellite instability (MSI-H) due to defective DNA mismatch repair (MMR) is a characteristic of the majority of tumors from kindreds with hereditary nonpolyposis colorectal cancer (HNPCC) and a subset of sporadic cancers. To better understand the molecular characteristics of colon cancers with MSI-H, we analyzed these cancers for alterations of genes, such as APC, beta-catenin, and TCF-4 genes, involved in the Wnt signaling pathway. Following the National Cancer Institute (NCI) criteria, 385 unselected colon cancers were classified as follows: 50 (13%) MSI-H tumors, 36 (9%) low-frequency MSI (MSI-L) tumors, and 299 (78%) microsatellite stable (MSS) tumors. The frequency of APC mutations was significantly lower in MSI-H tumors (9 out of 50) than in MSI-L (12 out of 20) and MSS (66 out of 100) tumors (P = 0.0005 and P < 0.0001, respectively). In contrast, the frequency of exon 3 mutations in the beta-catenin gene was higher in MSI-H tumors (10 out of 50) than in MSI-L tumors (0 out of 30; P = 0.0110) and MSS tumors (3 out of 100; P = 0.0010). Frameshift mutations in a (A)9 tract of the TCF-4 gene were detected in 44% (22 out of 50) of MSI-H tumors, but not in any of the 20 MSI-L tumors or 40 MSS tumors. In total, 78% of MSI-H tumors and 84% of the remaining tumors had at least one alteration in APC, beta-catenin, or the TCF-4 genes. Although further analysis is needed to functionally characterize the consequences of each of these alterations on beta-catenin/TCF target gene expression, our results suggest that the activation of the Wnt signaling pathway plays a pivotal role in colon tumorigenesis, irrespective of MSI status.

Advanced glycation end products in Descemet's membrane and their effect on corneal endothelial cell

PURPOSE

[corrected] The purpose of this study was to evaluate the effect of advanced glycation end products (AGEs) in Descemet's membrane on the attachment and spreading of the corneal endothelial cells.

METHODS

An anti-AGEs monoclonal antibody (6D12), which recognizes a N(epsilon)-carboxymethyl lysine (CML)-protein adduct as an epitope, was used for immunohistochemistry and enzyme-linked immunosorbent assay (ELISA). Fresh bovine Descemet's membrane was incubated for 4 weeks in the buffered solution with 500 mM of glucose-6-phosphate (G-6-P). In the incubated Descemet's membrane, the immunohistochemical localization of CML was examined. Type I collagen-, type IV collagen-, fibronectin-, or laminin-coated 96-well plates were glycated by G-6-P. The amount of CML was determined by ELISA using 6D12. Cultured bovine corneal endothelial cells were seeded onto glycated or non-glycated extracellular matrix (ECM) in 96-well plates and allowed to attach for 3 hours. The number and the surface area of the attached cells were examined.

RESULTS

Immunoreactivity to CML was detected in Descemet's membrane incubated in the buffered solution containing G-6-P. Glycation of fibronectin and laminin decreased the number and the surface area of the attached corneal endothelial cells. Aminoguanidine in the incubation mixture inhibited CML formation of ECM components and increased the number and the surface area of the attached corneal endothelial cells in a dose-dependent manner.

CONCLUSIONS

AGE formation on fibronectin and laminin attenuated the attachment and spreading of the corneal endothelial cells. AGEs' formation in Descemet's membrane may be responsible for the corneal endothelial cell loss with aging and corneal endothelial abnormalities in diabetic patients

Need for sling surgery in patients with large cystoceles and masked stress urinary incontinence

BACKGROUND

We studied the need for sling surgery in patients who suffered from large cystoceles and masked stress urinary incontinence.

METHODS

Twenty patients who had large cystoceles but neither evidence nor history of stress incontinence were enrolled in this study. The cystocele was reduced using a reducing device. Masked urinary incontinence was identified by a 60 m pad weighing test and a stress test. The cystocele was reduced using a pessary ring in 14 patients, or a vaginal pack formed of two rolls of ordinary 28 x 28 cm gauze in six patients. Ten of 20 patients were diagnosed with masked stress urinary incontinence and were treated with anterior colporrhaphy and a suburethral sling procedure. The other 10 patients were continent after use of a cystocele reducing device and were treated with anterior colporrhaphy alone. Average follow-up periods of the patients with or without masked stress urinary incontinence were 51.2 months (range, 24.0-72.0 months) or 57.6 months (range, 27.0-70.0 months), respectively.

RESULTS

One of the 10 patients diagnosed with masked stress incontinence had mild stress urinary incontinence postoperatively. None of the 10 continent patients had stress incontinence after anterior colporrhaphy alone.

CONCLUSIONS

Reducing devices of protruding cystocele were clinically useful in the detection of masked stress incontinence. Sling surgery was effective to prevent emerging stress urinary incontinence for patients who suffered from cystocele and masked stress incontinence.

Glycoxidation-modified macrophages and lipid peroxidation products are associated with the progression of human diabetic nephropathy

The aim of this study is to investigate the role of glomerular macrophages activated by glycoxidation and lipid peroxidation products in the progression of glomerular lesions in diabetic nephropathy. Renal biopsy samples from 43 patients with diabetes (age, 54 +/- 14 years) and 10 control cases were immunohistochemically examined for the expression of carboxymethyllysine (CML), a representative glycoxidative product; oxidized phosphatidylcholine (Ox-PC), a representative lipid peroxidation product; leukocyte common antigen (LCA); CD68; and macrophage scavenger receptor (MSR) class A. The severity of the diffuse lesions in each glomerulus was histologically graded from 0 to IV. When grade II and III lesions had Kimmelstiel-Wilson (KW) nodules, they were placed in a new category called grade III with KW nodules. The number of cells positive for CML, Ox-PC, LCA, CD68, and MSR was compared in different grades. The number of macrophages per glomerulus increased with the glomerular lesion grade and was highest in grade III with KW nodules. Conversely, the number of lymphocytes did not parallel the grade of glomerular lesions. Almost 50% of macrophages contained CML, and more than 40% of those were observed in exudative lesions, tuft adhesions, and at the periphery of KW nodules. Ox-PC accumulated in 50% of CML-positive macrophages, which coexpress MSR. Macrophages positive for CML and Ox-PC increased with the grade. Glomerular macrophages may be activated by glycoxidative and lipid peroxidation products through MSR and may have a role in the development of human diabetic glomerulosclerosis.

Twelve hours exposure to inhomogeneous high magnetic field after logarithmic growth phase is sufficient for drastic suppression of Escherichia coli death

When Escherichia coli B was aerobically grown at 43 degrees C in a medium whose concentration was one-fourth that of the Luria-Bertani (LB) medium supplemented with 1.5 g/l of glutamic acid, drastic cell death was observed after the end of the logarithmic growth phase. However, when the same experiment was conducted under inhomogeneous 5.2-6.1 T magnetic field, cell death was extremely suppressed and the ratio of viable cell number under high magnetic field to that under geomagnetic field reached as much as 100,000. When the magnetic field exposure was restricted to 12 h after the logarithmic growth phase, a similar high degree of suppressive effect on the death was observed. The findings that the amount of sigma S protein encoded by the rpoS gene under the high magnetic field was larger than that under the geomagnetic field, and that the magnetic field effect disappeared when the rpoS gene-deficient strain was cultivated under the high magnetic field, suggest the interaction of magnetic field with a stationary phase specific gene.

Morphological evidence for lipid peroxidation and protein glycoxidation in spinal cords from sporadic amyotrophic lateral sclerosis patients

For determining whether both the spinal cord motor neurons and glial cells are exposed to increased oxidative stress in amyotrophic lateral sclerosis (ALS), we performed an immunohistochemical investigation of end products of lipid peroxidation and protein glycoxidation in spinal cords from seven sporadic ALS patients and seven age-matched control individuals. In the ALS spinal cords, immunoreactivities for adducts of 4-hydroxy-2-nonenal-histidine and crotonaldehyde-lysine as markers of lipid peroxidation, N(epsilon)-(carboxymethyl)lysine as a marker of lipid peroxidation or protein glycoxidation, and pentosidine as a marker of protein glycoxidation were localized in the gray matter neuropil and almost all of the motor neurons, reactive astrocytes and microglia/macrophages, whereas none of the immunoreactivities for N(epsilon)-(carboxyethyl)lysine or argpyrimidine as markers of protein glycoxidation or enzymatic glycolysis, or pyrraline or imidazolone as markers of nonoxidative protein glycation were detectable. The control spinal cords displayed no significant immunoreactivities for any of these examined products. Our results indicate that in sporadic ALS, both lipid peroxidation and protein glycoxidation are enhanced in the spinal cord motor neurons and glial cells, and suggest that the formation of certain products in these abnormal reactions is implicated in motor neuron degeneration.

Sodium butyrate induces growth arrest and senescence-like phenotypes in gynecologic cancer cells

We demonstrated here the growth-suppressing effects of sodium butyrate (NaB) on human endometrial and ovarian cancer cells. The arrest of cells at the G1 checkpoint accounted for this effect. NaB-mediated p21 might arrest endometrial and ovarian cancer cells at the G0/G1 phase by eliciting pRb unphosphorylation. To demonstrate the role of pRb regulation by p21, we measured the sensitivity to NaB of cervical cancer cells in which pRb had been inactivated by HPV E7. The cervical cancer cells displayed a sensitivity in NaB-mediated G2/M arrest in addition to their sensitivity in G0/G1 arrest. Arrest at G0/G1 and G2/M accompanied induction of senescence-like phenotypes (SLPs). Most importantly, the effect of NaB on senescence induction was not coupled with the predominance of hypophosphorylated pRb forms in the cervical cancer cells. This suggested that NaB had the potential to elicit SLPs through p21-mediated withdrawal from cell cycle progression. The consequences of p21 induction were manifold. The effects of NaB on gynecologic cancer cell growth indicated its potential use in cancer treatment. NaB was effective even in the cancer cells with mutant p53 and/or Rb genes by eliciting cell senescence.

Granulocyte/macrophage colony-stimulating factor plays an essential role in oxidized low density lipoprotein-induced macrophage proliferation

We and other groups have recently demonstrated that oxidized low density lipoprotein (Ox-LDL) induces proliferation of macrophages in vitro. Since previous immunohistochemical studies demonstrated that macrophages and macrophage derived foam cells proliferated in situ in atherosclerotic lesions, it seems reasonable to expect that the Ox-LDL-induced macrophage proliferation might be linked to the development of atherosclerotic lesions. Thus, clarification of the molecular cascades of Ox-LDL-induced macrophage proliferation is expected to enhance our knowledge of the pathogenesis of atherosclerosis. Recently, we demonstrated that the activation of PKC leads to release into the culture medium of granulocyte/macrophage colony-stimulating factor (GM-CSF) which plays an important role in Ox-LDL-induced macrophage proliferation. In this review article, we mainly show the role of GM-CSF in the Ox-LDL-induced macrophage proliferation. Moreover, based on our recent findings, we summarize the Ox-LDL-induced signaling pathway for macrophage proliferation.

Association of matrilysin mRNA expression with K-ras mutations and progression in pancreatic ductal adenocarcinomas

The matrix metalloproteinase matrilysin has been implicated in the progression of gastrointestinal and other cancers. The aim of this study was to examine matrilysin mRNA expression and determine whether it is correlated with K-ras mutations and/or progression of pancreatic carcinoma. Using the semiquantitative reverse transcriptase-polymerase chain reaction (RT-PCR), we analyzed 11 pancreatic cancer cell lines and 70 pancreatic adenocarcinoma tissues for matrilysin mRNA expression. The results were correlated with clinicopathological characteristics and K-ras mutations. Significant amounts of matrilysin mRNA were detected in six of the eight cell lines with K-ras mutations but not in the three cell lines with wild-type K-ras. Matrilysin mRNA was detected in 57 (81.4% ) of the 70 tumor tissues and in all of the eight liver metastases, but not in any of the adjacent non-tumorous tissues. Matrilysin expression was significantly correlated with the size of tumor, tumor spreading, lymph node metastasis, advanced pathologic tumor-node- metastasis stage and K-ras mutations. The relative amounts of matrilysin mRNA in tumor tissues increased with increase in tumor stage and were highest in liver metastatic tumor tissues. Our results suggest that matrilysin, the expression of which is correlated with K-ras mutations, plays a key role in tumor growth and progression of pancreatic carcinoma.