Extracellular and intracellular factors regulating the migration direction of a chemotactic cell in traveling-wave chemotaxis

This report presents a simple model that describes the motion of a single Dictyostelium discoideum cell exposed to a traveling wave of cyclic adenosine monophosphate (cAMP). The model incorporates two types of responses to stimulation by cAMP: the changes in the polarity and motility of the cell. The periodic change in motility is assumed to be induced by periodic cAMP stimulation on the basis of previous experimental studies. Consequently, the net migration of the cell occurs in a particular direction with respect to wave propagation, which explains the migration of D. discoideum cells in aggregation. The wave period and the difference between the two response times are important parameters that determine the direction of migration. The theoretical prediction compared with experiments presented in another study. The transition from the single-cell state of the population of D. discoideum cells to the aggregation state is understood to be a specific example of spontaneous breakage of symmetry in biology.

Protein S exacerbates alcoholic hepatitis by stimulating liver natural killer T cells

BACKGROUND

Alcohol consumption is a major cause of liver injury but the mechanisms are not completely understood. Protein S (PS) is an anticoagulant glycoprotein with multiple functions. The role of PS in liver injury is unknown.

OBJECTIVES

This study investigated the role of PS in acute alcoholic hepatitis.

METHODS

A mouse overexpressing human PS (hPS-TG) was generated in which acute hepatitis was induced by intraperitoneal injection of ethanol.

RESULTS

The levels of serum liver enzymes and liver tissue inflammatory cytokines and the degree of hepatic steatosis were significantly increased in hPS-TG mice treated with ethanol compared with ethanol-treated wild type (WT) mice. Cell expansion, activation and inhibition of apoptosis were significantly augmented in natural killer T (NKT) cells from hPS-TG mice compared with WT mice. Liver mononuclear cells from hPS-TG mice express higher levels of inflammatory cytokines than those from WT mice after stimulation with a specific stimulant of NKT cells in vitro. In a co-culture system of hepatocytes and NKT cells, the effects of PS on ethanol-mediated cell injury were suppressed by a CD1d neutralizing antibody. Alcoholic liver injury was significantly improved in mice pre-treated with PS siRNA and anti-protein S antibody compared with control mice. Patients with alcoholic hepatitis showed significantly increased plasma PS levels and enhanced liver expression of PS and CD1d compared with controls.

CONCLUSIONS

The results of this study suggest that PS exacerbates acute alcoholic hepatitis by inhibiting apoptosis of activated NKT cells.

Abstract P5-13-07: Genetic polymorphism of estrogen metabolizing enzyme CYP17A1 rs743572 impacts on serum testosterone level in Japanese premenopausal women

The incidence of breast cancer in Japanese women has doubled in all age groups over the past two decades. We recently demonstrated that this marked increase is mostly due to an increase in the estrogen receptor (ER)-positive subtype, and we created risk prediction models for ER-positive breast cancer in both pre- and post- menopausal women using genetic factors (single nucleotide polymorphism (SNP)), environmental risk factors, serum hormones and growth factors by logistic regression analysis. Serum level of testosterone, which is the precursor of estradiol in estradiol synthesis, was found to be a risk predictor in both pre- and post- menopausal women. On the other hand, it has been reported that some SNPs, including those of estrogen-related genes such as ESR1 and CYP17A1, are correlated with breast cancer risk by genome-wide association studies. To acquire some insights into this mechanism, we analyzed genetic factors (14 SNPs), serum hormones and growth factors (estradiol, testosterone, prolactin, insulin-like growth factor 1 (IGF1) and IGF binding protein 3 (IGFBP3)) in 913 women with breast cancer and 278 disease-free controls for correlation between them.

Serum testosterone and prolactin levels were significantly higher in ER-positive breast cancer patients than in disease-free controls in both pre- (p<0.0001, p<0.0001) and post- (p<0.0001, p = 0.007) menopausal women, and serum estradiol level was significantly higher in ER-positive breast cancer patients than in disease-free controls only in premenopausal women (p = 0.0005). There were significant differences in serum hormone levels among the women with each SNP genotype (homozygotes of major allele, heterozygotes and homozygotes of minor allele), including testosterone among rs743572 genotype (p = 0.014), estradiol among rs827421 genotype (p = 0.016), IGF-1 among rs6905370 genotype (p = 0.032), and prolactin among rs1042522 genotype (p = 0.035) in premenopausal women, as well as estradiol among rs3803662 genotype (p = 0.027) and IGFBP3 among rs6905370 genotype (p = 0.036) in postmenopausal women. In particular, serum testosterone level was significantly different among the rs743572, which is one of the enzymes that convert testosterone to estradiol, of genotypes (AA: 0.308 +/- 0.180 ng/ml, AG: 0.319 +/- 0.193 ng/ml and GG: 0.380 +/- 0.187 ng/ml, p = 0.014). On the other hand, the rs743572 heterozygotes of CYP17A1 have been reported to have increased breast cancer risk than homozygotes of both the major allele and minor allele in premenopausal women. Further studies are required to clarify this mechanism.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P5-13-07.

Abstract P4-12-06: A mammographic density prediction model using environmental factors, endogenous hormones and growth factors in Japanese women

The incidence of breast cancer in Japanese women has doubled in all age groups over the past two decades, making it important to evaluate breast cancer risk factors in Japanese women. It is well known that mammographic density is positively associated with breast cancer risk in Western countries, and mammographic density is known to be affected by some environmental factors, serum hormones, and growth factors. We performed stepwise variable selection in a multiple regression model with fifteen independent variables as described below, based on the Akaike information criteria (AIC) to build a mammographic density prediction model using a dataset of 1191 women (913 women with breast cancer and 278 disease-free controls). The variables included were: environmental risk factors (body-mass index (BMI), age at menarche, pregnancy, age at first birth, breastfeeding, family history of breast cancer, age at menopause, use of hormone replacement therapy, alcohol intake and smoking), serum hormones and growth factors (estradiol, testosterone, prolactin, insulin-like growth factor 1 (IGF1) and IGF binding protein 3 (IGFBP3)) and mammographic density. The resulting prediction model is:

Mammographic density = + 0.000476 (IGF1) −0.0605 (testosterone) − 0.0508 (IGFBP3) − 0.00683 (age) − 0.0175 (BMI) + 0.00883 (age at menarche) − 0.0153 (breast feeding), (R2 = 0.336).

In this model, IGF1, testosterone, IGFBP3, age, BMI, age at menarche, and breastfeeding were considered to be important factors. IGF1 and age at menarche were positively associated with mammographic density, while on the other hand testosterone, IGFBP3, age, BMI, and breast feeding were negatively associated with mammographic density. Further studies are required to build a modified model incorporating serial measurements of serum hormones and growth factors to take into account time-dependent changes of serum hormones and growth factors, and to assess its accuracy.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P4-12-06.

P4-10-11: Genetic and Environmental Predictors, Endogenous Hormones and Growth Factors and Risk of Estrogen Receptor-Positive Breast Cancer in Japanese Women

The incidence of breast cancer in Japanese women has doubled in all age groups over the past two decades. We have recently demonstrated that this marked increase is mostly due to an increase in the estrogen receptor (ER)-positive subtype. It is necessary to establish risk factors capable of predicting the risk of ER-positive breast cancer which will enable the efficient selection of candidates for preventive chemotherapy. We analyzed genetic factors, including 14 single nucleotide polymorphisms (SNPs), environmental risk factors (body-mass index (BMI), age at menarche, pregnancy, age at first birth, breastfeeding, family history of breast cancer, age at menopause, use of hormone replacement therapy, alcohol intake and smoking), serum hormones and growth factors (estradiol, testosterone, prolactin, insulin-like growth factor 1 (IGF1) and IGF binding protein 3 (IGFBP3)) and mammographic density in 913 women with breast cancer and 278 disease-free controls. To identify important risk factors, risk prediction models for ER-positive breast cancer in both pre- and postmenopausal women were created by logistic regression analysis. In premenopausal women, 1 SNP (CYP19A1-rs10046), age, pregnancy, breastfeeding, alcohol intake, serum levels of prolactin, testosterone and IGFBP3 were considered to be risk predictors. In postmenopausal women, 1 SNP (TP53-rs1042522), age, BMI, age at menopause, serum levels of testosterone and IGF1 were identified as risk predictors. Risk factors may differ between women of different menopausal status, and inclusion of common genetic variants and serum hormone measurements as well as environmental factors might improve risk assessment models. Further validation studies will clarify appropriate risk groups for preventive chemotherapy.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P4-10-11.

P3-03-01: Low Expression of microRNA-210 Is an Independent Good Prognostic Factor in Japanese Triple-Negative Breast Cancer Patients

Background: microRNAs (miRNAs) have emerged as a new class of non-coding genes involved in regulating cell proliferation, differentiation, and viability. Recent studies have identified miR-210 among a set of hypoxia-regulated miRNAs and demonstrated a direct regulatory role of hypoxia-inducible factor-1 alpha (HIF-1 a) in its transcription. High expression of miR-210 has been reported to be a poor prognostic factor in several types of cancers including breast.

Materials and Methods: TaqMan MicroRNA assays for miR-210 expression were performed in 219 breast cancers (58 triple-negative (TNBCs), and 161 ER-positive and HER2−negative). Correlations between miR-210 expression and clinicopathological factors were analyzed. The effects of several variables on survival were tested by Cox proportional hazards regression analysis.

Results: miR-210 expression in TNBCs was significantly higher than in ER-positive and HER2−negative breast cancers (p<0.001). Patients whose TNBCs had low miR-210 expression experienced significantly better disease-free and overall survival compared with high miR-210 expressors (p=0.02 and p=0.05, respectively). Notably, among 40 node-negative TNBCs, 5-year disease-free survival was approximately 60% in patients whose tumors had high or intermediate miR-210 expression (n=26), while no patients with low miR-210 expression (n=14) suffered recurrent disease. Cox univariate and multivariate analyses demonstrated that low expression of miR-210 was an independent good prognostic factor in TNBCs.

Patients achieving clearance of HCV with interferon therapy recover from decreased retinol-binding protein 4 levels

Retinol-binding protein 4 (RBP4) is a recently identified adipokine that is elevated in the blood in several insulin-resistant states. We investigated the association between plasma RBP4 and histological and biochemical characteristics of chronic hepatitis C (CHC), as well as changes in RBP4 levels following interferon therapy. Eighty-one patients with CHC infected with genotype 1 received treatment with peginterferon plus ribavirin. Histological data were available for 41 out of 81 patients before treatment, and the degree of fibrosis, inflammation and steatosis was assessed. Plasma levels of RBP4 were determined in serial samples (before, at the end of treatment, and at 6 months post-treatment). RBP4 levels were lower in CHC patients than in control subjects (34.6 +/- 12.3 microg/mL vs 46.2 +/- 10.5 microg/mL; P <or= 0.001). Higher RBP4 levels were linked to lower alanine aminotransferase (ALT) (P < 0.01), higher cholinesterase (P < 0.01), hyperlipidaemia (P < 0.01), hyperglycaemia (P < 0.05), and higher platelet (P < 0.01) count in CHC patients. Plasma RBP4 levels tended to decrease concomitantly with the grade of histological fibrosis, activity, and steatosis. RBP4 levels at baseline were not a predictor of the response to antiviral therapy in CHC patients. After peginterferon plus ribavirin therapy, only patients who had achieved clearance of hepatitis C virus had higher post-treatment RBP4 levels. This study suggests that an association between RBP4 levels and abnormal metabolic features, and that liver function may determine RBP4 levels in CHC patents. This is further supported by the observation that RBP4 levels increased significantly after treatment only in sustained virological response (SVR) patients and reached levels comparable to those of healthy subjects.

Comparison of hepatic oxidative DNA damage in patients with chronic hepatitis B and C

8-Hydroxydeoxyguanosine (8-OHdG) is a promutagenic DNA lesion produced by hydroxyl radicals and is recognized as a useful marker in estimating DNA damage induced by oxidative stress. The aim of this study was to clarify the clinical significance of hepatic 8-OHdG levels in patients with chronic viral hepatitis. Hepatic 8-OHdG accumulation was investigated in patients with chronic hepatitis C (CH-C) (n = 77) and chronic hepatitis B (CH-B) (n = 34) by immunohistochemical staining of liver biopsy samples. 8-OHdG positive hepatocytes were significantly higher in patients with CH-C compared to CH-B (median 55.0 vs 18.8 cells/10(5) mum(2), P < 0.0001). The number of positive hepatocytes significantly increased with the elevation of serum aminotransferase levels, especially in CH-C patients (8-OHdG vs alanine aminotransferase (ALT)/aspartate aminotrasferase (AST) were r = 0.738/0.720 in CH-C and 0.506/0.515 in CH-B). 8-OHdG reactivity was strongly correlated with body and hepatic iron storage markers in CH-C (vs serum ferritin, r = 0.615; vs hepatic total iron score, r = 0.520; vs hepatic hepcidin mRNA levels, r = 0.571), although it was related to serum HBV-DNA titers (r = 0.540) and age of patients (r = -0.559) in CH-B. These results indicate that hepatic oxidative DNA damage is common in chronic viral hepatitis, in particular chronic HCV-infected patients, suggesting a possible link between chronic hepatic inflammation and hepatocarcinogenesis. The strong positive correlation between hepatic DNA damage and iron overload suggests that iron content is one of the most likely mediators of hepatic oxidative stress and iron reduction may be beneficial to reduce the incidence of hepatic cancer in CH-C patients.

Adverse effects of ivermectin on the dung beetles, Caccobius jessoensis Harold, and rare species, Copris ochus Motschulsky and Copris acutidens Motschulsky (Coleoptera: Scarabaeidae), in Japan

Effects of the antiparasitic drug, ivermectin, on the dung beetles, Caccobius jessoensis Harold, 1867 and the rare species, Copris ochus Motschulsky, 1860 and Copris acutidens Motschulsky, 1860 were studied in laboratory and field experiments in Hokkaido, Japan. Ivermectin was detected in dung from 1 to 21 or 28 days following treatment, with a peak on the first day after treatment in two pour-on administrations (500 microg kg(-1)), although there were considerable differences between the two peaks. In C. jessoensis, brood balls constructed by the female were not reduced in the dung of treated cattle except for seven days after treatment in experiment 2. Also, there was no significant difference in the mean weight of brood balls between dung from treated and control cattle. However, the emergence rates were significantly reduced in dung 1-3 days after treatment. In the field study, brood balls constructed by C. jessoensis were more abundant in dung from treated cattle in experiment 1, but adult emergence was significantly reduced at one and seven days after treatments. Adult mortality of C. ochus Motschulsky at 90 days after the beginning of rearing was 11.1% in dung from control cattle with 22 brood balls constructed, whereas it was 84% in dung from treated cattle with no brood balls and/or ovipositioning. Also, in C. acutidens Motschulsky, adult mortality at 90 days after the beginning of rearing was 3.6% in dung from control cattle with 13 brood balls constructed, whereas it was 94.1% in dung from treated cattle with no brood balls or ovipositioning. The environmental risk in the use of ivermectin during breeding period of dung beetles in pasture is discussed.

Effects of bezafibrate in patients with chronic hepatitis C virus infection: combination with interferon and ribavirin

An association of hepatitis C virus (HCV) with low-density lipoproteins (LDL) in serum of patients with chronic hepatitis C (CHC) has been suggested. We conducted a prospective study in CHC patients complicated with hyperlipidaemia, to examine whether bezafibrate, which is commonly used for treatment of hyperlipidaemia, reduces serum HCV-RNA titre and improves liver dysfunction. Fifteen patients received daily oral bezafibrate treatment (400 mg/day) for 8 weeks, and its effects on serum lipids, transaminases, HCV-RNA titres, and HCV-RNA titres bound to LDL were evaluated. Fifteen untreated patients with CHC and hyperlipidaemia were used as controls. The mean serum alanine aminotransferase levels and HCV-RNA titres significantly decreased at the end of bezafibrate therapy in the treated group (105 +/- 34 to 80 +/- 32 IU/L, P = 0.02 and 2.23 +/- 2.71 to 1.78 +/- 2.38 x 10(7) copies/mL, P < 0.01 respectively), but no changes were observed in the control group. Serum HCV-RNA titres bound to LDL, as quantified by immunoprecipitation using anti-LDL antibody, also decreased in all 15 treated patients [5.55 +/- 6.59 to 1.07 +/- 1.58 x 10(6) copies/ml, P < 0.01 (mean reduction rate was -78.5 +/- 17.0%)]. Sucrose density-gradient ultracentrifugation study revealed that HCV-RNA-decreased density fractions after the bezafibrate were identical to LDL-density fractions (1.015-1.062 g/mL). Eight CHC patients were treated with bezafibrate, interferon, and ribavirin triple therapy for 32 weeks, and four patients achieved sustained virological response to therapy. This pilot study provides further evidence of an association between HCV and LDL in serum and suggests the potential usefulness of bezafibrate as an anti-HCV reagent for the treatment of CHC patients.

Immunohistochemical detection of early-stage carcinogenesis of oral leukoplakia by increased DNA-instability and various malignancy markers

The degree of DNA instability as determined by immunohistochemical staining with anti-single-stranded DNA antibody after acid hydrolysis (the DNA instability test) was used as a marker of malignancy. The test was applied to tissues of oral leukoplakia assessed histopathologically as hyperplasia (38 cases), mild (12 cases), moderate (11 cases) and severe (8 cases) dysplasia, and invasive squamous cell carcinoma (SCC, 20 cases). Tissues were subjected to immunohistochemical staining for proliferating cell nuclear antigen (PCNA), p53, DNA-fragmentation factor 45 (DFF45), analysis of various AgNORs parameters, and triple immunostaining for vascular endothelial growth factor (VEGF), CD34, and PCNA. The DNA instability test was positive in 20 (100%) SCC cases, 8 (100%) severe dysplasia cases, 8 (72.7%) moderate dysplasia cases, 6 (50.0%) mild dysplasia cases, and 9 (23.7%) hyperplasia cases, indicating malignancy. The proportion of lesions positive for PCNA, p53, DFF45, and values of AgNORs parameters steadily increased from hyperplasia to mild, moderate and severe dysplasia, and SCC, especially in those showing positive DNA instability test, indicative of malignancy. Based on these results, 44.9% of leukoplakia were malignant tissues, namely carcinoma in situ. The proportion of PCNA-positive vascular endothelial cells in the vicinity of VEGF-positive epithelial lesion was significantly higher than that of negative DNA instability lesions, as revealed by immunohistochemical triple staining for VEGF, CD34, and PCNA. Our results suggest that increased DNA instability, enhanced proliferative activity, p53 mutation, and induction of DFF45 and VEGF may allow cancer cell proliferation, enhance their survival by escaping apoptosis, and provide abundant nutrients during early-stage carcinogenesis of oral leukoplakia.

Detection of cardiomyocyte apoptosis in forensic autopsy cases

The purpose of the present study was to determine reliable parameters for the detection of apoptotic cells for use as a diagnostic marker during the early stage of acute myocardial infarction (AMI) in forensic autopsy cases. Myocardial tissues taken from forensic autopsy cases were examined by immunohistochemical and molecular-biological methods using the terminal deoxynucleotidyl transferase-mediated dUTP biotin nick end-labelling (TUNEL) and the DNA laddering methods. In cases of AMI with a time period between 2 h from onset to death and 20 h post-mortem time, the nuclei of cardiomyocytes were stained positive with the TUNEL method and DNA fragmentation of myocardial cells was detected by agarose gel electrophoresis. Similar findings were obtained in cases of carbon monoxide (CO) intoxication. However, no apoptotic cells were found in other cases such as methamphetamine (MAP) intoxication, tetrodotoxin intoxication, alcohol intoxication, asphyxia, head injury, heart injury or myocarditis. These findings suggested that it would be possible to apply TUNEL-positive cells as a diagnostic marker during the early stages of AMI.

Route of feeding influences the production and expression of tumor necrosis factor alpha in burned rats

The effect of nutritional route on tumor necrosis factor alpha (TNF-alpha) production in burned rats was examined. Scald burns covering about 30% of the whole body surface area were inflicted on 43 male Wistar rats weighing about 200g. The animals were divided into three groups: CHOW (n = 10), total parenteral nutrition (TPN) (n = 22), and total enteral nutrition (TEN) (n = 11), continuously given a chow diet, TPN solution, or an enteral diet, respectively, for 7 days after the burn injury. The rate of detection of TNF-alpha in plasma on day 7 was significantly higher in the TPN group than in the CHOW or TEN groups. The messenger RNA (mRNA) expression of TNF-alpha was significantly increased in the spleen, lungs, liver, and ileum of the rats receiving TPN compared with the CHOW and TEN rats. On the other hand, the expression of TNF-alpha mRNA was markedly decreased in the thymus of the TPN group compared with the CHOW group. The mortality rate in the TPN group (63.6%) was higher than that in the CHOW (0.0%) or TEN (27.3%) groups on day 7 after burn injury. These data suggest that TPN increases the expression of TNF-alpha mRNA in organ tissues and systemic TNF-alpha production, and reduces the survival rate of rats after thermal injury, but TEN does not.

Y-chromosomal STR haplotype in the Japanese population

Allele and haplotype frequencies of seven Y-chromosome STR loci from samples of 108 unrelated Japanese males living in Aichi Prefecture.