Cigarette Smoking Habits Research Articles

Epithelial Mucin Stores Are Increased in the Large Airways of Smokers With Airflow Obstruction

Habitual cigarette smoking is associated with chronic mucus hypersecretion, but the relationship between mucus abnormalities and airflow obstruction in smokers is uncertain. We collected bronchial biopsy samples and epithelial brushings from 24 smokers with and without airflow obstruction and 19 nonsmoking healthy control subjects. Epithelial mucin stores, mucin immunostains, and goblet cell morphology were quantified in bronchial biopsy samples using stereology, and mucin gene expression was quantified in epithelial brushings using real-time reverse transcriptase-polymerase chain reaction. Goblet cell size and number were higher than normal in smokers (both p < 0.05), leading to a 2.2-fold increase in the volume of stored mucin in the epithelium per surface area of basal lamina (1.94 +/- 0.31 microm(3)/microm(2) vs 4.32 +/- 0.55 microm(3)/microm(2) in control subjects vs smokers, p = 0.001). The increase in stored mucin occurred because of an increase in MUC5AC (p = 0.018) and despite a decrease in MUC5B (p < 0.0001). Stored mucin was significantly higher in the subgroup of smokers with airflow obstruction (p = 0.029) and correlated with FEV(1)/FVC even when controlling for diffusing capacity as a measure of emphysema (p = 0.034). Epithelial mucin stores are increased in habitual smokers because of goblet cell hypertrophy and hyperplasia, and the pattern of mucin gene expression is abnormal. The highest epithelial mucin stores are found in smokers with airflow obstruction, suggesting a mechanistic link between epithelial mucin dysregulation and airflow obstruction.

Expression of human telomerase reverse transcriptase (hTERT) protein is significantly associated with the progression, recurrence and prognosis of oral squamous cell carcinoma in Taiwan

This study used an immunohistochemical technique to examine the expression of human telomerase reverse transcriptase (hTERT) protein in 82 specimens of OSCC, 116 specimens of oral epithelial dysplasia (OED), and 21 specimens of normal oral mucosa (NOM). The cytoplasmic and nuclear hTERT staining intensity (SI; 0, no staining; 1, weak; 2, moderate; 3, strong), labeling indices (LIs, defined as the percentage of positive cells in total cells), and labeling scores (LSs, defined as LI x SI) in OSCC, OED, and NOM samples were calculated and compared among groups. The correlation between the cytoplasmic or nuclear hTERT LS in OSCCs and clinicopathological parameters or survival of OSCC patients was analyzed statistically. The mean cytoplasmic hTERT LSs increased significantly from NOM (87+/-17%) through OED (95+/-18%) to OSCC samples (114+/-33%, p=0.000). The mean nuclear hTERT LSs also increased from NOM (80+/-14%) to OED (91+/-20%) and then decreased to OSCC samples (86+/-35%) with no statistically significant difference among the 3 groups. A significant correlation was found between the higher mean cytoplasmic hTERT LSs and OSCCs occurring in male patients (p=0.023), with larger tumor sizes (T3 and T4, p=0.048), with more advanced clinical stages (stages 3 and 4, p=0.033), or from patients with areca quid chewing (p= 0.029), cigarette smoking (p=0.027), or alcohol drinking habit (p=0.025). In addition, OSCC patients with nuclear hTERT LSs greater than 100% were prone to have a higher recurrence rate (p=0.044) and a lower 5-year survival rate (p=0.011). Our results indicate that the increased expression of hTERT protein is an early event in oral carcinogenesis and hTERT may be a biomarker for OSCCs. Measuring the amount of cytoplasmic or nuclear expression of hTERT in OSCC samples may predict the oral cancer progression, recurrence, and prognosis in Taiwan.

Interaction of genetic polymorphisms in cytochrome P450 2E1 and glutathione S-transferase M1 to breast cancer in Taiwanese woman without smoking and drinking habits

P450 (CYP) and glutathione S-transferase (GST) are involved in the activation and detoxification of many potential carcinogens. Although, the interaction between environmental exposure and genetic polymorphisms of cytochrome P450 2E1 (CYP2E1) and glutathione S-transferase M1 (GSTM1) in breast cancer has been assessed, the gene-gene interactions between CYP2E1 and GSTM1 related to breast cancer have not been focused on and reported. We conducted a hospital-based case-control study to investigate whether the genetic interaction effects of CYP2E1 and GSTM1 modify the risk of developing breast cancer independent of the effect of cigarette smoking and alcohol consumption. Individuals with the C2/C2 genotype of CYP2E1 had a lower risk (OR = 0.24, 95% CI = 0.08-0.74) when compared with those with the C1/C1 genotype. However, there was no significant difference (OR = 1.05, 95% CI = 0.73-1.50) in the GSTM1 genotype frequency between the cases with breast cancer and that of the controls. When individuals with the genotype of C1/C1 or C1/C2 of CYP2E1 and the wild-type of GSTM1 were compared with those of C2/C2 of CYP2E1 and the null-type of GSTM1 however, we found a significantly increased risk (OR = 3.50, 95% CI = 1.01-16.55) in the breast cancer patients. Our findings indicated a gene-gene interaction between CYP2E1 and GSTM1 was accessible to developing breast cancer in Taiwanese women without the habits of cigarette smoking and alcohol consumption even though independent effects of CYP2E1 and GSTM1 were weak or non-significant and suggest that environmental carcinogen besides cigarette and alcohol consumption could induce breast cancer.

Gender differentials in the evolution of cigarette smoking habits in a general European adult population from 1993–2003

BackgroundDescribe the recent evolution of cigarette smoking habits by gender in Geneva, where incidence rates of lung cancer have been declining in men but increasing in women.MethodsContinuous cross-sectional surveillance of the general adult (35–74 yrs) population of Geneva, Switzerland for 11 years (1993–2003) using a locally-validated smoking questionnaire, yielding a representative random sample of 12,271 individuals (6,164 men, 6,107 women).ResultsIn both genders, prevalence of current cigarette smoking was stable over the 11-year period, at about one third of men and one quarter of women, even though smoking began at an earlier age in more recent years. Older men were more likely to be former smokers than older women. Younger men, but not women, tended to quit smoking at an earlier age.ConclusionThis continuous (1993–2003) risk factor surveillance system, unique in Europe, shows stable prevalence of smoking in both genders. However, sharp contrasts in age-specific prevalence of never and former smoking and of ages at smoking initiation indicate that smoking continues a long-term decline in men but has still not reached its peak in women.

Cigarette smoking and colorectal cancer risk in Germany: A population‐based case–control study

Studies have shown fairly consistent positive relationships between smoking and risk of colorectal adenomas, but have yielded inconsistent results for colorectal cancer. Issues relating to the duration, cumulative dose of smoking and the effect of smoking cessation on colorectal cancer risk still need clarification. In a population-based case-control study in Germany, we recruited 540 incident cases of colorectal cancer and 614 controls matched to cases by sex, 5-year age groups and county of residence from January 2003 to June 2004. Subjects were aged>or=30 years, and provided information on risk factors of colorectal cancer, including lifetime cigarette smoking habits, in personal interviews. Odds ratios (OR) and 95% confidence intervals (CI) were computed using conditional logistic regression models, adjusting for potential confounders. Compared with nonsmokers, there was an increased risk for smoking for >or=30 years (OR: 1.25, 95% CI: 0.90-1.75) and a significant risk increase for >or=40 pack-years of smoking (OR: 1.92, 95% CI: 1.13-3.28). Stratification by sex yielded higher risk estimates among females than that among males, with adjusted ORs of 3.5 (95% CI: 1.29-9.52) and 1.15 (0.69-1.91) for women and men, respectively, following >or=30 pack-years of smoking (pinteraction=0.18). Among smokers, risk reduction was observed after >or=20 years of quitting smoking and was significant for >or=40 years (OR: 0.46; 95% CI: 0.21-0.98), when compared to current smokers (p for linear trend=0.05). This study supports the hypothesis that smoking for a long duration at a high cumulative dose increases the risk for colorectal cancer, particularly among women, and suggests that there is risk reduction after longterm smoking cessation.

Exposure to traffic pollutants and effects on 17-β-estradiol (E2) in female workers

The aim of the study is to evaluate whether the occupational exposure to urban pollutants including endocrine disruptors (EDs) could cause alterations in plasma 17-beta-estradiol (E2) levels and related diseases (adverse pregnancy outcome and mental health disorders) in female traffic police compared to a control group. After excluding the subjects with the principal confounding factors, traffic police and controls were matched by age, years of police work, age of menarche, menstrual cycle day, body mass index (BMI), drinking habit, cigarette smoking habit, habitual intake of soy or liquorice in diet and habitual consumption of Italian coffee. Thirty-seven traffic police and 31 controls (seventh day; follicular phase of the ovarian cycle); 38 traffic police and 42 controls (14th day; ovulatory phase of the ovarian cycle); and 25 traffic police and 28 controls (21st day; lutheal phase of the ovarian cycle) were included in the study and then matched for the above-mentioned variables. In follicular and in lutheal phases, mean E2 levels were significantly lower in traffic police compared to controls. The distribution of E2 values in traffic police and controls was significant in follicular, ovulatory and lutheal phases. In ovulatory phase, mean E2 levels were lower but not significant in traffic police compared to controls. An increase was found concerning mental health disorders referred to in the questionnaire items in traffic police compared to controls, although the difference was not significant. Considering that the potential confounding effect of extraneous factors was controlled for by restricting the study population and by matching traffic police and controls on the above-mentioned variables, our results suggest that occupational exposure to urban pollutants, EDs included, might alter E2 plasma concentrations. E2 could be used in occupational set as an early biomarker of exposure to urban pollutants, valuable for the group, even before the onset of the related pathologies (adverse pregnancy outcome and mental health disorders).

GSTP1 Genetic Polymorphism Is Associated with a Higher Risk of DNA Damage in Pesticide-Exposed Fruit Growers

Pesticide exposure is associated with various neoplastic diseases and congenital malformations. Animal studies also indicated that pesticides may be metabolized by cytochrome P450 3A5 (CYP3A5) enzymes, paraoxonases (PON1 and PON2), or glutathione S-transferases (GSTM1, GSTT1, and GSTP1). However, little is known about the genotoxicity of pesticides in people with various genetic polymorphisms of human CYP3A5, PON1, PON2, GSTM1, GSTT1, and GSTP1. Thus, this study was designed to investigate whether various metabolic genotypes are more susceptible to DNA damage in pesticide-exposed fruit growers. Using the Comet assay, the extent of DNA damage was evaluated in the peripheral blood of 91 fruit growers who experienced pesticide exposure and 106 unexposed controls. Questionnaires were administered to obtain demographic data, cigarette smoking habits, medical, and occupational histories. The genotypes for CYP3A5, PON1, PON2, GSTM1, GSTT1, and GSTP1 genes were identified by PCR. The results showed that subjects experiencing high or low pesticide exposure had a significantly greater DNA tail moment (DAN damage) than did controls. The multiple regression model also revealed that age (P < 0.01), high pesticide exposure (P < 0.01), low pesticide-exposure (P < 0.01), and CYP3A5 (P = 0.04) and GSTP1 (P = 0.02) genotypes were significantly associated with an increased DNA tail moment. Further analysis of environmental and genetic interactions revealed a significant interaction for GSTP1 genotypes to influence DNA tail moment for the high pesticide exposure group. These results suggest that individuals with susceptible metabolic GSTP1 genotypes may experience an increased risk of DNA damage elicited by pesticide exposure.

Relationship between Metabolic Syndrome and Cigarette Smoking in the Japanese Population

We investigated the link between metabolic syndrome and cigarette smoking in the Japanese population. A total of 3,177 Japanese subjects aged 20-79 years were recruited in a cross-sectional clinical investigation study. Habits of cigarette smoking were obtained at interviews by well-trained staff. The diagnosis of metabolic syndrome was based on the new criterion in Japan. Four hundred and forty men (35.3%) and 142 women (7.4%) were current smokers. Three hundred thirty four men (26.8%) and 69 women (3.6%) were diagnosed as metabolic syndrome. The prevalence of current smoker in subjects with metabolic syndrome was significantly higher than in subjects with non-metabolic syndrome in men with and without adjustment for age. The prevalence of metabolic syndrome in men with Brinkman index > or = 600 was significantly higher than that in men with Brinkman index < 600. The present study indicated that cigarette smoking may be an important modifiable factor in Japanese men with metabolic syndrome.

Risk of p53 gene mutation in esophageal squamous cell carcinoma and habit of betel quid chewing in Taiwanese

A recent report suggested that BQ (BQ) chewing significantly correlated with the occurrence of esophageal squamous cell carcinoma (ESCC) in Taiwanese. BQ chewing was shown to be associated with p53 mutation in oral cancers. However, the relationship between BQ chewing and p53 mutation in ESCC is unclear. Seventy-five primary ESCC patients were enrolled for mutational analysis of the p53 gene using polymerase chain amplification and direct sequencing of amplified product. Thirty-seven mutations of the p53 gene were detected in 45.5% (34/75) of tumor specimens. These mutations significantly clustered in exon 5 (21/37) of the p53 gene. The incidence of p53 mutations did not associate with clinicopathological characteristics or the habits of cigarette smoking or alcohol consumption. However, BQ chewers exhibited significantly higher incidence of p53 gene mutations than non-chewers (67.6% vs 32.4%, P = 0.007). After controlling the confounding factors of cigarette smoking and alcohol intake, BQ chewing still showed significant association with the incidence of p53 mutation in ESCCs (RR = 4.23; 95% CI, 1.317-13.60). The A:T to G:C transition (8/37, 21.6%) and G:C to T:A transversion (5/23, 13.5%) were the prevalent spectrum of p53 gene mutations. All A:T to G:C transitional mutations occurred in patients with the habits of BQ chewing and cigarette smoking. Noticeably, alcohol consumption could enhance this peculiar spectrum of p53 mutation in ESCC. Accordingly, p53 might be an important molecular target of BQ carcinogens in the development of ESCC in Taiwanese.

Incidence rates of oral cancer and oral pre‐cancercous lesions in a 6‐year follow‐up study of a Taiwanese aboriginal community

In a previous article, we reported the prevalence rates of oral mucosal lesions in an aboriginal community from an epidemiological survey of oral pre-cancerous lesions. Since 1997, the authors have started regular follow-up of the study population originally investigated. Thus, it has been possible to obtain incidence rates for the various oral pre-cancerous lesions and conditions. There were 194 persons without any oral lesion in the 1997 screening. During the clinical follow-up investigation and during the analysis of biopsies from pre-cancerous lesions, we discovered six new lesions (including cancer and pre-cancerous lesions) from five participants. All of the five persons were areca/betel quid chewers, and only one mixed areca/betel quid chewing with cigarette smoking habit. The age-standardized incidence rates for quid lesion, oral submucous fibrosis (OSF) and squamous cell carcinoma (SCC) were 267.0, 374.1 and 146.2 per 100,000 person-years, respectively, for areca/betel quid chewers. As compared with the rates from India and the general Taiwanese population, the study community encountered a serious problem of oral lesions.

Clozapine Toxicity Associated with Smoking Cessation

We report on a 28-year-old white woman with chronic psychotic-affective illness who abruptly stopped her decade-long habit of heavy daily cigarette smoking while maintained on clozapine at 450 mg/d. Within several days, she developed dry mouth, muscle spasms, dizziness, and blurred vision with dilated and sluggish pupils, with worsening sedation and confusion. Her combined serum concentration of clozapine + norclozapine was 2.5 microg/mL, compared with levels of about 600 ng/mL at daily doses of 350 mg at other times while smoking. Reducing the dose of clozapine led to rapid alleviation of these symptoms. Additional experience with and without smoking in this case further documented the effect of smoking to decrease circulating levels of clozapine. These observations add to the conclusion that cigarette smoke can increase clearance of many drugs, calling for special caution during treatment with potentially toxic substances and dose reduction in anticipation of smoking cessation.

Polymorphism in DNA repair genes and oral squamous cell carcinoma in Thailand

DNA repair capacity is essential in maintaining cellular functions and homeostasis. However, the repair capacity can be altered based on DNA sequence variations in DNA repair genes and thus may cause cancer susceptibility. We investigated associations between polymorphisms in DNA repair genes and oral squamous cell carcinoma (OSCC) in a Thai population. Nine known single nucleotide polymorphisms (SNPs) in five common DNA repair genes were investigated: XRCC1 (Arg194Trp and Arg399Gln); XRCC3 (Thr241Met); XPC (PAT and Lys939Gln); XPD (exon 6, and Lys751Gln); and MGMT (Trp65Cys and Leu84Phe). We studied 106 cases and 164 healthy controls that were frequency-matched by age (±5 years), gender, and cigarette smoking and alcohol drinking habits. The genotype assays were performed using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. The R version 2.0.1 statistical software was applied for statistical analysis of association. Based on multivariate analyses, we found that the variant genotypes with XRCC3 241Met exhibited a >3-fold elevated risk ( OR = 3.3 , 95% CI = 1.31 – 8.36 , p = 0.01 ) for OSCC. There was a marginally significant risk observed in variants with XRCC1 194Trp ( OR = 1.81 , 95% CI = 0.91 – 3.63 , p = 0.09 ) and XPD exon 6 ( OR = 1.71 , 95% CI = 0.93 – 3.16 , p = 0.09 ). Combination of the variant genotypes of these three susceptibility genes was associated with a highly significant risk for OSCC ( OR = 9.43 , 95% CI = 1.98 – 44.9 , p < 0.01 ). From further multivariate analyses, the variants with XRCC1 194Trp and possibly XRCC3 241Met interacted with tobacco and alcohol to further increase the risk ( OR = 3.37 95% CI = 1.41 – 8.02 , p < 0.01 ; OR = 2.92 , 95% CI = 0.94 – 9.04 , p = 0.06 ). On the other hand, increased risk was detected in non-betel chewers ( OR = 2.88 , 95% CI = 1.31 – 6.31 , p < 0.01 ; OR = 2.61 , 95% CI = 0.97 – 7.11 , p = 0.06 ) who carry the two variant genotypes, respectively. Males with the variants XRCC1 194Trp or X RCC3 241Met had a higher risk of developing OSCC than males with the corresponding wild-type genotypes ( OR = 2.72 , 95% CI = 1.34 – 5.52 , p < 0.01 ; OR = 2.95 , 95% CI = 1.12 – 7.75 , p < 0.05 ). Such association was not detected in females. Interestingly, the risk increased in female carriers of XPD exon 6 ( OR = 3.93 , 95% CI = 1.14 - 13.6 , p < 0.05 ). We could not demonstrate a significant interaction of these SNPs with age in this study. Our data indicate that the variant genotypes with XRCC3 241Met and possibly XRCC1 194Trp and XPD exon 6 contribute to OSCC development in a Thai population. In addition, these SNPs influence the repair of DNA damage that is caused by environmental risk factors for oral cancer.

Cigarette Smoking and Fat Distribution in 21, 828 British Men and Women: A Population‐based Study

To examine the relationship between cigarette smoking habits and fat distribution in a population-based cohort of men and women. We analyzed cross-sectional data from 21,828 men and women who were 45 to 79 years of age, residents in Norfolk, United Kingdom, and were recruited between 1993 and 1997. Cigarette smoking habits and other lifestyle factors were assessed using self-reported questionnaires. Anthropometric measures were obtained during a health examination. Waist-hip ratio was highest among current smokers and least among never smokers after adjusting for age, BMI, alcohol intake, total energy intake, physical activity, and education. Higher waist-hip ratio was directly associated with higher smoking pack-years in current and former smokers and inversely with duration since quitting smoking in former smokers. Adjusting for age, BMI, and other covariates, current smokers had higher waist circumference but lower hip circumference compared with former or never smokers. Cigarette smoking habits seem to influence fat distribution patterns. Although smokers have lower mean BMI compared with nonsmokers, they have a more metabolically adverse fat distribution profile, with higher central adiposity. The explanation for this association may help elucidate the mechanisms underlying the adverse health consequences of cigarette smoking and abdominal obesity.

P-023 Overexpression of hepatocyte growth factor in alveolar type II Cells and lung adenocarcinoma cells in patients with cigarette smoking habit

P-023 Overexpression of hepatocyte growth factor in alveolar type II Cells and lung adenocarcinoma cells in patients with cigarette smoking habit

Interleukin-12 and interleukin-16 in periodontal disease

The immune system plays an important role in the pathological process of periodontitis. Interleukin-12 (IL-12) is produced by monocytes, macrophages and neutrophils. These cells are proinflammatory infiltrates in periodontitis tissues. High IL-12 will contribute to the immune reaction to Th1 type. IL-12 is an inducer of INF-r production. IFN-γ itself can also activate IL-12 production. Lipopolysaccharides (LPS) of periodontopathogens are also activators of IL-12. Interleukin-16 (IL-16) can cause the high affinity of IL-2 receptors on CD4+ cells and is chemotaxis to Th1 cells and CD4+ T cells. IL-16 can stimulate monocytes to produce proinflammatory cytokines and is highly associated with inflammation including arthritis, enteritis and allergic rhinitis. However, the information on IL-12 and IL-16 in periodontitis is not clear. In this study, 105 GCF samples were collected from 19 periodontal disease patients and 6 healthy ones. The clinical periodontal indices, the habits of cigarette smoking and alcohol drinking were recorded. ELISA was used to determine the levels of IL-12 and IL16 in the GCF. In the non-smoking/non-alcohol-drinking individuals: (1) the total amount of IL-12 (but not IL-16) was significantly higher in chronic periodontitis (CP) sites than gingivitis (G) or healthy (H) sites; (2) the diseased sites (CP + G) had a significantly higher total amount of IL-12 (but not IL-16) than the H sites. Among CP sites, both the concentration and total amount of IL-16 (but not IL-12) were significantly higher in alcohol drinkers/cigarette smokers as compared to the non-drinkers/non-smokers. CP sites of the drinkers/smokers also had significantly deeper probing pocket depth than sites of those without these two habits. IL-12 and IL-16 may be related to the pathogenesis of periodontal disease, but within the periodontitis sites, IL-16 may be related to disease severity in alcohol drinkers/smokers.

Breast Cancer Incidence in Women Prenatally Exposed to Maternal Cigarette Smoke

Clinical studies show that maternal cigarette smoking reduces pregnancy estrogen levels. Women prenatally exposed to maternal cigarette smoke may, therefore, have a lower breast cancer risk because the fetal mammary gland's exposure to maternal estrogen is decreased. Associations between prenatal maternal cigarette smoke exposure and breast cancer, however, have not been observed in previous case-control studies that relied on exposure assessment after the onset of cancer. At the start of this study, cigarette smoking history was obtained directly from the mother. The National Cooperative DES Adenosis project was a follow-up study of health outcomes in women prenatally exposed to diethylstilbestrol (DES). At the start of the study, women's mothers provided information about cigarette smoking habits during the time they were pregnant with the study participant. In the current study, the breast cancer rates are compared among 4031 women who were or were not prenatally exposed to maternal cigarette smoke. The resultant relative rate (RR) is adjusted for potential confounding by other breast cancer risk factors using Poisson regression modeling. Fetal exposure to maternal cigarette smoke appeared to be inversely associated with breast cancer incidence (RR = 0.49; 95% confidence interval [CI] = 0.24-1.03). The inverse association was more apparent among women whose mothers smoked 15 cigarettes or fewer per day than among daughters of heavier smokers. There were, however, too few cases to precisely estimate a possible dose-response relationship. These results support the hypothesis that in utero exposure to maternal cigarette smoke reduces breast cancer incidence.

The effects of chewing areca/betel quid with and without cigarette smoking on oral submucous fibrosis and oral mucosal lesions

The purpose of this study was to investigate the risk of areca/betel quid chewing with or without cigarette smoking on oral submucous fibrosis (OSF) and other oral mucosal lesions. A stratified case-control study was designed. There were in total 102 patients with oral mucosal lesions or OSF (confirmed pathologically) in the case group. OSF (n = 62) and oral mucosal lesions (n = 62) in 102 subjects were separately analyzed for men and women investigating their risks. For OSF, people with both smoking and chewing habits had a statistically significant odds ratio (OR) 8.68 (95% CI = 1.87, 40.23). For the group of people with chewing habit only and without any lifetime cigarette smoking habit, the OR was 4.51 (95% CI = 1.20, 16.94). For other oral mucosal lesions, people with mixed habits and chewing only had also significant risks (OR = 8.37 and 3.95, respectively). For both OSF and other oral lesions, the ORs of mixed habits and chewing only were both higher in women than in men. The areca/betel quid used in Taiwan does not contain any tobacco product. The only way of areca/betel quid could synergize with any tobacco product is through cigarette smoking. A statistically significant association with oral mucosal lesions and OSF was still found in the group of areca/betel quid chewing only.

Urinary acetonitrile concentrations correlate with recent smoking behaviour

To assess the concentration of acetonitrile (a saturated aliphatic nitrile) in the urine of habitual cigarette smokers and non-smokers, as exposure to smoke can be measured by monitoring ambient air or by in vivo tests, but acetonitrile measured in exhaled breath is reportedly a quantitative marker of recent smoking behaviour. The study included 101 volunteers (57 men and 44 women, mean age 49 years). An absence of urinary tract infection on urine analysis or clinical history was mandatory. The subjects were classified into five groups, i.e. a control group of non-smokers and four groups according to the number of cigarettes smoked daily. Urine samples were stored at 8 degrees C until acetonitrile was measured, within 24 h of collection, using proton-transfer reaction mass spectrometry (PTR-MS). Each measurement was repeated at least 10 times, and the mean used for statistical analysis. The mean (sd) acetonitrile level in the urine of 46 non-smokers was 3.74 (1.78) parts per billion volatile (ppbv). The concentration of acetonitrile increased with the number of cigarettes smoked daily, the highest concentration being in the subgroup of 13 very heavy smokers (>30 cigarettes/day) with means up to 28.04 (5.38) ppbv. PTR-MS is a quick, noninvasive online method for determining urinary acetonitrile levels, a marker for recent active and passive smoking behaviour, and thus for checking compliance. As smoking has been shown to affect the genesis of bladder cancer, further studies are required to determine the association of acetonitrile with bladder cancer.

Higher expressions of p53 and proliferating cell nuclear antigen (PCNA) in atrophic oral lichen planus and patients with areca quid chewing

The aim of the study was to examine the expressions of p53 and proliferating cell nuclear antigen (PCNA) in oral lichen planus (OLP) in relation to its clinical behavior and the patients' oral habits. Immunohistochemical study was carried out to investigate the expressions of p53 and PCNA in 56 OLP specimens. The results were correlated with the clinical behavior of the disease and the patients' oral habits. The expression rates were further compared with those of normal oral mucosa (NOM), epithelial hyperkeratosis (EH), epithelial dysplasia (ED), and squamous cell carcinoma (SCC). The staining rate of p53 (28.6%) and PCNA labeling index (LI) (27.6 +/- 8.8%) in OLP were similar to those in EH ( P = .868, .074, respectively), but higher than those of NOM and lower than those of ED and SCC (all P < .05). In OLP, no significant correlations were found between p53 or PCNA expression and the patients' age, gender, lesion duration, location, size, number of site, presence of pain, presence of local irritant, and the habits of alcohol drinking and cigarette smoking (all P > .05). In addition, the mean PCNA LI of p53+ cases was close to that of p53- cases (P = .38). However, the staining rate of p53 in OLP was higher in areca quid (AQ) chewers compared to abstainers (P = .001), and the mean PCNA LI in atrophic cases was higher than that in hypertrophic cases (P = .029). Interestingly, the staining rate of p53 and mean PCNA LI were significantly increased in AQ chewers with atrophic OLP (100%, 36.7% +/- 9.0%, respectively), which were similar to those in ED and SCC (all P > .05). Although this study could not confirm the precancerous nature of OLP by the relatively low p53 and PCNA expression, the results do suggest that atrophic form OLP and patients with AQ chewing habit may have a higher disease activity in view of higher expression rates of p53 and PCNA in the lesions.

Safrole–DNA adducts in tissues from esophageal cancer patients: clues to areca-related esophageal carcinogenesis

Epidemiological studies have demonstrated that areca quid chewing can be an independent risk factor for developing esophageal cancer. However, no studies are available to elucidate the mechanisms of how areca induces carcinogenesis in the esophagus. Since the areca nut in Taiwan contains a high concentration of safrole, a well-known carcinogenic agent, we analyzed safrole–DNA adducts by the 32P-postlabelling method in tissue specimens from esophageal cancer patients. In total, we evaluated 47 patients with esophageal cancer (16 areca chewers and 31 non-chewers) who underwent esophagectomy at the National Taiwan University Hospital between 1996 and 2002. Of the individuals with a history of habitual areca chewing (14 cigarette smokers and two non-smokers), one of the tumor tissue samples and five of the normal esophageal mucosa samples were positive for safrole–DNA adducts. All patients positive for safrole–DNA adducts were also cigarette smokers. Such adducts could not be found in patients who did not chew areca, irrespective of their habits of alcohol consumption or cigarette smoking ( p < 0.001, comparing the areca chewers with non-chewers). The genotoxicity of safrole was also tested in vitro in three esophageal cell lines and four cultures of primary esophageal keratinocytes. In two of the esophageal keratinocyte cultures, adduct formation was increased by treatment with safrole after induction of cytochrome P450 by 3-methyl-cholanthrene. This paper provides the first observation of how areca induces esophageal carcinogenesis, i.e., through the genotoxicity of safrole, a component of the areca juice.