CXCL4 is a novel nickel-binding protein and augments nickel allergy.

BACKGROUND: Nickel (Ni) is the most frequent metal allergen and induces a TH1 -dependent type-IV allergy. Although Ni2+ is considered to bind to endogenous proteins, it currently remains unclear whether these Ni-binding proteins are involved in Ni allergy in vivo. We previously reported the adjuvant effects of lipopolysaccharide (LPS) in a Ni allergy mouse model. As LPS induces a number of inflammatory mediators, we hypothesized that Ni-binding protein(s) are also induced by LPS. OBJECTIVE: The objective of this study was to purify and identify Ni-binding protein(s) from serum taken from LPS-injected mice (referred as LPS serum) and examined the augmenting effects of these Ni-binding protein(s) on Ni allergy in an in vivo model. METHODS: BALB/cA mice were sensitized with an i.p. injection of NiCl2 and LPS. Ten days after sensitization, mice were challenged with NiCl2 by an i.d. injection into ear pinnae. Ni-binding protein(s) were purified by Ni-affinity column chromatography and gel filtration. RESULTS: Lipopolysaccharide serum, but not serum taken from saline-injected mice, augmented ear swelling induced by Ni-allergic inflammation. Ni-binding, but not non-binding fraction, purified from LPS serum augmented Ni-allergic inflammation. Mass spectrometry and Western blotting detected CXCL4 in the active fraction. A batch analysis with Ni-sepharose and a surface plasmon resonance analysis revealed direct binding between CXCL4 and Ni2+ . Recombinant CXCL4 augmented Ni-allergic inflammation and exerted adjuvant effects at the sensitization phase. CONCLUSIONS: These results indicate that CXCL4 is a novel Ni-binding protein that augments Ni allergy at the elicitation and sensitization phases. This is the first study to demonstrate that the Ni-binding protein augments Ni allergy in vivo.

Resin monomers act as adjuvants in Ni-induced allergic dermatitis in vivo.

Resin monomers (RMs) are inflammatory agents and are thought to cause allergic contact dermatitis (ACD). However, mouse models are lacking, possibly because of the weak antigenicities of RMs. We previously reported that inflammatory substances can promote the allergic dermatitis (AD) induced by intradermally injected nickel (Ni-AD) in mice. Here, we examined the effects of RMs on Ni-AD. To sensitize mice to Ni, a mixture containing non-toxic concentrations of NiCl2 and an RM [either methyl methacrylate (MMA) or 2-hydroxyethyl methacrylate (HEMA)] was injected intraperitoneally or into ear-pinnae intradermally. Ten days later, a mixture containing various concentrations of NiCl2 and/or an RM was intradermally injected into ear-pinnae, and ear-swelling was measured. In adoptive transfer experiments, spleen cells from sensitized mice were transferred intravenously into non-sensitized recipients, and 24 h later NiCl2 was challenged to ear-pinnae. Whether injected intraperitoneally or intradermally, RM plus NiCl2 mixtures were effective in sensitizing mice to Ni. AD-inducing Ni concentrations were greatly reduced in the presence of MMA or HEMA (at the sensitization step from 10 mM to 5 or 50 µM, respectively, and at the elicitation step from 10 µM to 10 or 100 nM, respectively). These effects of RMs were weaker in IL-1-knockout mice and in macrophage-depleted mice. Cell-transfer experiments in IL-1-knockout mice indicated that both the sensitization and elicitation steps depended on IL-1. Challenge with an RM alone did not induce allergic ear-swelling in mice given the same RM + NiCl2 10 days before the challenge. These results suggest that RMs act as adjuvants, not as antigens, to promote Ni-AD by reducing the AD-inducing concentration of Ni, and that IL-1 and macrophages are critically important for the adjuvant effects. We speculate that what were previously thought of as "RM-ACD" might include ACD caused by antigens other than RMs that have undergone promotion by the adjuvant effects of RMs.

Allergy-inducing nickel concentration is lowered by lipopolysaccharide at both the sensitization and elicitation steps in a murine model.

BACKGROUND: Nickel (Ni) is the major cause of contact allergy. We previously found that lipopolysaccharide (LPS, a cell-surface component of gram-negative bacteria) markedly promotes Ni allergy in a murine model. Establishing the minimum concentration or amount of Ni needed to induce allergic responses may help us to prevent or reduce such responses. OBJECTIVES: Using the above murine model, we examined the influence of LPS on the minimum allergy-inducing concentrations of Ni (Ni-MAICs) at the sensitization step and at the elicitation step. METHODS: BALB/c mice were sensitized by intraperitoneal injection of a mixture containing various concentrations of LPS and NiCl(2). Ten days later, their ear pinnas were challenged intradermally with a mixture containing various concentrations of LPS and NiCl(2), and ear swelling was measured. RESULTS: Without LPS, the Ni-MAICs at the sensitization and elicitation steps were around 1×10(-2) mol L(-1) and 1×10(-5) mol L(-1) , respectively. Sensitization with NiCl(2) + LPS did not alter the value at elicitation. Surprisingly, LPS markedly reduced these Ni-MAICs (to around 1×10(-6) molL(-1) at sensitization, with 25 µg mL(-1) LPS, and 1×10(-12) mol L(-1) at elicitation, with 0·5 µg mL(-1) LPS). The effect of LPS depended on its concentration and the timing of its injection. CONCLUSIONS: Our findings suggest that: (i) Ni-MAIC is higher at sensitization than at elicitation; (ii) once sensitization is established, Ni allergy can easily be induced by a low concentration of Ni; and (iii) a bacterial milieu or infection may greatly facilitate the establishment and elicitation of Ni allergy.

Histamine amplifies immune response of gingival fibroblasts.

Histamine is an important mediator in immune responses, but it is unclear whether periodontal tissues express histamine receptors and are able to respond to histamine. We hypothesized that histamine, inflammatory cytokines, and bacterial components released in inflamed periodontal tissues may be synergistically involved in periodontitis. The present study showed that human gingival fibroblasts mainly express histamine receptor H1R, and responded to histamine to produce interleukin (IL)-8. Stimulation of gingival fibroblasts with tumor necrosis factor-alpha, IL-1alpha, and lipopolysaccharide markedly induced IL-8 production, and the IL-8 production was synergistically augmented in the presence of or pre-treatment with histamine. Selective inhibitors of mitogen-activated protein kinases (MAPKs), nuclear factor (NF)-kappaB, and phospholipase C (PLC) significantly inhibited the synergistic effect. These results indicate that histamine induces IL-8 production from gingival fibroblasts through H1R, and synergistically augments the inflammatory stimuli by amplification of the MAPK and NF-kappaB through H1R-linked PLC. Abbreviations used: HDC, histidine decarboxylase; LPS, lipopolysaccharide; IL, interleukin; TNF, tumor necrosis factor; HR, histamine receptor; PLC, phospholipase C; MAPK, mitogen-activated protein kinase; NF, nuclear factor; ERK, extracellular signal-related kinase; JNK, c-Jun N-terminal kinase; R, receptor; TLR, Toll-like receptor; alpha-MEM, alpha-minimum essential medium; FCS, fetal calf serum; RT-PCR, reverse-transcriptase polymerase chain-reaction; ELISA, enzyme-linked immunosorbent assay; SD, standard deviation; LDH, lactate dehydrogenase.

Lipopolysaccharide promotes and augments metal allergies in mice, dependent on innate immunity and histidine decarboxylase.

BACKGROUND: Few adequate murine models exist for metal allergies, it being especially difficult to induce Ni allergy in mice. OBJECTIVE: We examined the effect of lipopolysaccharide (LPS) on allergies to Ni and other metals in mice. METHODS: Ten days after sensitization with a metal salt and LPS, the ears were challenged with the same metal salt. RESULTS: LPS+NiCl(2) (1 mM) was effective at sensitizing mice to Ni, LPS being effective at very low concentrations whether injected intradermally or intraperitoneally. The ear-swelling response to Ni was more severe and more rapid in C57BL/6 mice than in BALB/c mice. In mast-cell-deficient mice, TNF-alpha-deficient mice, and interestingly even in nude (T cell deficient) mice, NiCl(2)+LPS induced a Ni allergy similar in degree to that in the respective control mice, but it induced Ni allergy only weakly in TLR4-mutant mice, macrophage-depleted mice, and IL-1-deficient mice. The activity of the histamine-forming enzyme histidine decarboxylase (HDC) in the ears increased in parallel with ear swelling, and HDC-deficient mice were resistant to ear swelling. Challenge with NiCl(2)+LPS augmented ear swelling (vs. NiCl(2) alone). LPS induced effective sensitization to other metals (Cr, Co, Pd, or Ag). CONCLUSIONS: These results indicate that in mice, LPS is a very important inducer of metal allergies, and potently promotes them (dependent on both innate immunity and HDC induction in cells other than mast cells). We discussed the idea that the bacterial environment is important for the establishment of metal allergies and for their provocation, and that the current thinking (including the contribution of T cells) should be reappraised in future studies.

Alcohol, smoking, and dietary status and susceptibility to malignant lymphoma in Japan: results of a hospital-based case-control study at Aichi Cancer Center.

Recent increase in the incidence of malignant lymphoma (ML) suggests possible involvement of lifestyle or environmental factors in its genesis. However, evidence for an effect of lifestyle factors, especially diet, on ML risk among Japanese is lacking. To explore the possibility that lifestyle factors exert an influence, we have conducted a hospital-based case-control study with 333 histologically confirmed ML cases and 55904 non-cancer controls who first visited Aichi Cancer Center Hospital between 1988 and 1997. Multiple logistic regression analysis showed regular alcohol consumption to be associated with reduced risk of ML, whereas no risk change was observed for smoking. Some other factors including intake of vegetables (carrots and pumpkin), pork and fish showed partial associations, but their significance needs further clarification. From the previous study on genetic background for ML [Matsuo et al., Blood, 97, 3205 - 3209 (2001)], genetic variation combined with limited environmental factors should be targeted in future studies.

Association of family history and other risk factors with breast cancer risk among Japanese premenopausal and postmenopausal women.

OBJECTIVES: To determine the impact of family history (FH) on anthropometric and reproductive risk factors for breast cancer, a case-referent study was conducted using data from the Hospital-based Epidemiologic Research Program at Aichi Cancer Center (HERPACC), Japan. METHODS: In total, 1584 breast cancer cases were included and 15,331 women, confirmed as free of cancer, were recruited as the referents. Odds ratios and 95% confidence intervals were determined by logistic regression analysis. Separate analyses were performed for premenopausal and postmenopausal women. RESULTS: Height, weight, and current body mass index (BMI) were positively associated with postmenopausal breast cancer regardless of FH, while these anthropometric factors did not alter risk in premenopausal women. The impacts of height and weight on postmenopausal breast cancer were more pronounced among FH women. There was little association with reproductive risk factors for premenopausal or postmenopausal breast cancer in FH cases, in clear contrast to the non-FH cases. CONCLUSIONS: These findings suggest some differences in risk impact of common etiologic factors between familial breast cancer and sporadic cases that may give pointers to further analysis of host-specific factors. They imply that avoidance of obesity after menopause may reduce the risk of breast cancer, regardless of FH.

Dietary factors and lung cancer risk in Japanese: with special reference to fish consumption and adenocarcinomas.

To investigate risk modification for lung cancer with diet in Japanese, we conducted a hospital-based case-control study and evaluated variation in influence with the histological type. We recruited 367 male and 240 female cases with adenocarcinomas, and 381 male and 57 female cases with squamous cell and small cell carcinomas. Controls comprised 2964 male and 1189 female cancer-free outpatients matched for sex and age with the cases. Odds ratios (ORs) and their 95% confidence intervals (CIs) for lung cancer were calculated with adjustment for potential confounding factors, using an unconditional logistic model. We found decreased ORs for adenocarcinomas in both males (OR = 0.51, 95% CI 0.31-0.84) and females (OR = 0.48, 95% CI 0.24-0.94) who consumed cooked/raw fish, but not dried/salted fish at the highest quartile frequency, compared with the lowest. Soybean curd consumption was associated with a decreased OR for female adenocarcinomas. Decreased ORs for squamous cell and small cell carcinomas were observed in males with frequent consumption of raw and green vegetables, fruit and milk, but consumption of carrot, pumpkin, egg and coffee was associated with increased ORs. This study suggests cooked/raw fish consumption lowers the risk of adenocarcinoma of the lung in Japanese.

[Epidemiology of breast cancer].

In Japan, the mortality rate from female breast cancer has increased in recent years. In 1998, the number of deaths from female breast cancer was 8,589, accounting for 7.7% of all female cancer deaths. The estimated number of new cases of female breast cancer in 1995 was 29,818, accounting for 15.3% of all sites, and its age-adjusted incidence rate was 39.8 per 100,000, ranking it top among the main sites of female cancer. As breast cancer is predicted to increase in the future, it is important for the primary prevention of breast cancer to avoid weight gain during adulthood, excess intake of fat, especially animal fat, and a high intake of alcohol. Physical activity and diets high in vegetables and fruits should be promoted.

Effectiveness of mass screening for breast cancer in Japan.

BACKGROUND: Breast cancer screening has been conducted in Japan mainly by physical examination, the standard method for breast cancer screening according to the Law of Health Services for the Elderly. The purpose of this study was to evaluate the effectiveness of mass screening for breast cancer in Japan. METHODS: We calculated the average coverage-rates for breast cancer screening per year from 1986 to 1995 for women aged 30-69 years for all of the 3255 municipalities in Japan, selecting "high coverage-rate" municipalities with average coverage-rates of 20%, 30%, 40% or more. Two municipalities were selected as "controls" for each high coverage-rate municipality, and were matched for population, National Health Insurance rate, and the age-adjusted death rate from cancer of the female breast in the period 1986-90. We compared the change in the age-adjusted death rate from 1986-90 to 1991-95 of the high coverage-rate municipalities and the comparable controls. RESULTS: The percent reduction in the age-adjusted death rate from cancer of the breast in the high coverage-rate municipalities was statistically significantly greater than those in the controls. CONCLUSIONS: The results suggest that mass screening for female breast cancer, mainly by physical examination, contributed to the reduction of mortality from breast cancer.

Subsite-specific risk factors for hypopharyngeal and esophageal cancer (Japan).

OBJECTIVES: To clarify subsite-specific risk factors for hypopharyngeal and esophageal cancers (HC and EC), we concluded a hospital-based case-referent study in Nagoya, Japan. METHODS: Subjects comprised 346 male cases with cancer of the hypopharynx (n = 62) or esophagus (upper [U-EC] 53, middle [M-EC] 159, lower [L-EC] 72), and 11,936 male referents free from cancer among first-visit outpatients aged 40-79 years in 1988-1997. Of histological confirmed cases, 93% comprised squamous cell carcinoma. Odds ratios (ORs) were estimated by a logistic regression model with adjustment for potential confounding factors. RESULTS: Cigarette smoking increased the OR for M-EC, and alcohol drinking elevated the ORs for all subsites. The trend of ORs for combined cases of M- and L-EC tended to increase with number of cigarettes (p = 0.056), and a decreasing trend of the ORs was found with years after quitting smoking (p = 0.006). The ORs for smoking with drinking were multiplicatively greater than those for smoking or drinking in combined cases of HC and EC. In contrast, daily raw vegetable consumption lowered the ORs for all subsites. CONCLUSIONS: This study suggests that the magnitude of risk with smoking is stronger for M-EC within the esophagus, and drinking increases the risk at any subsite.

Comparison of lifestyle and risk factors among Japanese with and without gastric cancer family history.

To find specific risk factors of gastric cancer (GC) independent of GC family history (GCFH), 2 studies were conducted using the database of the Hospital-based Epidemiological Research Program at Aichi Cancer Center: (i) a comparison of lifestyles between non-cancer cases with positive and negative GCFH status and (ii) a case-reference investigation of subjects with and without GCFH, treated separately. The first showed no significant variation of GCFH status with regard to smoking, drinking and most food habits. Multivariate analyses in the case-referent studies revealed odds ratios (ORs) for GC associated with habitual smoking of 2.78 (95% CI 1.22-6.28) for those with and 2.74 (95% CI 1.76-4.26) for those without GCFH. In individuals with GCFH, an independently lowered OR (0.52, 95% CI 0.27-0.99) was evident for frequent consumption of raw vegetables, whereas the opposite was noted for pickled vegetables (2. 39, 95% CI 1.28-4.45). No statistically significant interaction was found between GCFH and selected lifestyle items. In conclusion, our results suggest a limited influence of GCFH on risk factors for GC.

Prognostic significance of elevated cyclooxygenase 2 expression in primary, resected lung adenocarcinomas.

Recently, we demonstrated that elevated expression of cyclooxygenase 2 (COX-2) is frequently seen in a specific type of lung cancer, i.e., adenocarcinoma, and is possibly associated with its invasion and metastasis. Here, the prognostic significance of elevated COX-2 expression was evaluated in a cohort of 130 adenocarcinoma patients who had consecutively undergone potentially curative resections. Immunohistological examination showed the presence of tumor cells with markedly increased COX-2 immunoreactivity in 93 of 130 (72%) cases. No relationship was found between the increase in COX-2 expression and clinical outcomes when the entire cohort was considered (P = 0.099). Reasoning that the influence of the increase in COX-2 expression may have been obscured by the clinical and molecular pathogenetic complexities in cases with an advanced disease, we also separately analyzed the prognostic significance of increased COX-2 expression after stratification according to the disease stage. A significant relationship between elevated COX-2 expression and shortened patient survival was observed only in a cohort of patients with stage I disease (P = 0.034). These findings suggest that an increase in COX-2 expression may be clinically significant for the prognosis of patients undergoing surgical resection of early-stage adenocarcinomas and, thus, warrant further conclusive studies involving a larger cohort.

Comparative case-referent study of risk factors among hormone-related female cancers in Japan.

To assess the impact of reproductive and anthropometric factors as a risk indicator for female cancers in hormone-related organs, i.e., the breast, endometrium and ovary, we conducted a comparative case-referent study using data from the Hospital-based Epidemiologic Research Program at Aichi Cancer Center (HERPACC), Japan. The case group consisted of 1,465, 133 and 99 women who had first been diagnosed as having breast, endometrial and ovarian cancer, respectively. The referents were 25,488 female first-visit outpatients who had not previously been diagnosed with any type of cancer. The odds ratios (ORs) and their 95% confidence intervals (95%CI) were estimated using an unconditional logistic regression model. An inverse association with experience of delivery and a positive association with body mass index (BMI) and with change of BMI after 20 years of age, were observed consistently for all three cancer sites. We observed similar risk and protective factors for breast and endometrial cancer, but the effect of reproduction and overweight condition (BMI> or =25) were more prominent in endometrial cancer. Although the present study failed to find site-specific risk factors for ovarian cancer, the results provided evidence that being overweight and/or weight gain in adult life is a common risk factor for all three cancer sites. The results obtained from this study suggested that avoidance of weight gain may reduce the risk of female hormone-related cancers.

Effect of life styles on the risk of subsite-specific gastric cancer in those with and without family history.

To evaluate a combined effect of gastric cancer family history (GCFH) and selected living habits on the subsite-specific of gastric cancer, a hospital-based case-referent study was conducted in Tokai area of Japan. The study subjects were 850 newly diagnosed gastric cancer (GC) patients and 28,619 cancer-free first-visit outpatients. Odds ratios (ORs) of all subsites of GC in subjects with both GCFH and habitual smoking were significantly higher (OR = 4.22) compared with those with merely GCFH (OR = 1.81) or habitual smoking (OR = 2.83). When positive GCFH subjects frequently consumed raw vegetable, the risk of GC decreased in cardia (OR = 0.68), antrum (OR = 0.43) and all subsites (OR = 0.74). Our findings provided evidence that GCFH and habitual smoking increased the risk of GC with family history, while frequent intake of raw vegetable decreased the risk and it was modified by other environmental factors.

Effect of body size on breast-cancer risk among Japanese women.

With the use of data from the hospital-based epidemiologic research program at Aichi Cancer Center (HERPACC), the effect of body size on the risk of breast cancer was evaluated among Japanese women, who are generally leaner than white women. In total, 1,359 breast-cancer cases were included, and 24,207 women, confirmed as free of cancer, were recruited as a reference group. Odds ratios (OR) and 95% confidence intervals (95% CI) were determined by multiple-logistic regression analysis. Separate analyses were performed for pre- and post-menopausal women. Furthermore, stratification by decade of age was done to evaluate the effect of body size on the development of breast cancer. The results obtained from the present study were as follows. (1) Current body-mass index (BMI) was positively associated with postmenopausal breast cancer (OR 2.08, 95% CI 1.49-2.92 for highest quintile vs. lowest), although higher BMI did not affect the risk in pre-menopausal women. (2) Estimates of risk were below unity for BMI at around age 20 in post-menopausal women. (3) After stratifying BMI at around age 20, gaining BMI in later life was positively associated with increased risk, regardless of BMI in early life. These findings suggest that avoidance of marked weight gain during adult life, especially after natural menopause and/or after age 60, may reduce the risk of breast cancer.

Epidemiology and Prevention of Breast Cancer in the 21st Century.

The incidence and mortality of breast cancer are high in Western industrialized and relatively low Japan and other Asian countries. In Japan the incidence and mortality of breast cancer have gradually been increasing. Marrying later, having fewer children, a larger intake of fat, dairy products and meats and a larger body mass index in menopausal women may be related to the increased incidence of breast cancer in Japan. A review of risk factors identified from recent epidemio-logical studies in Japan indicates that obesity after 50 years of age is an important risk factor for post-menopausal breast cancer. Future estimations of cancer mortality and incidence predict that breast cancer will further increase to become a leading cancer in Japan in the 21st century.

p53 mutations in non-small-cell lung cancers occurring in individuals without a past history of active smoking.

Accumulating evidence suggests that the p53 gene is a good target for molecular epidemiological studies. We previously reported an association between the presence of p53 mutations and lifetime cigarette consumption. Although over 675 p53 mutations have been reported in lung cancers in the literature thus far, very little is known about the nature of such changes in lung cancers in the absence of a smoking background. In the present study, we therefore analysed 69 non-small-cell lung cancer specimens from individuals without any history of active smoking and identified p53 mutations in 26% of the cases. Statistical analysis of the present cohort of non-smokers also showed absence of significant relationship between p53 mutations and age, sex, histological type or disease stage. Comparison of mutational spectra between the present results in non-smokers and previously reported mutations in smokers clearly demonstrated G:C to T:A transversions to be significantly less frequent in non-smokers than in smokers (OR 5.35, 95% CI 1.77-16.12). Interestingly, G:C to C:G and G:C to A:T mutations were also observed in tumours of non-smokers at similar frequencies to G:C to T:A mutations, suggesting that these mutations can occur relatively frequently in the absence of active smoking. This study is, to our knowledge, the largest so far analysing a well-defined cohort of non-smokers in a single laboratory.