A dose-response relationship between the frequency of p53 mutations and tobacco consumption in lung cancer patients

Relationship of oral bacterial number with medical hospitalization costs in analysis of Diagnosis Procedure Combination database from single institution in Japan

Oral bacteria are known to be associated with perioperative complications during hospitalization. However, no presented reports have clarified the relationship of oral bacterial number with medical costs for inpatients. The Diagnosis Procedure Combination (DPC) database system used in Japan provides clinical information regarding acute hospital patients. The present study was conducted to determine the association of oral bacterial numbers in individual patients treated at a single institution with length of hospital stay and medical costs using DPC data. A total of 2369 patients referred by the medical department to the dental department at Hiroshima University Hospital were divided into the low (n = 2060) and high (n = 309) oral bacterial number groups. Length of hospital stay and medical costs were compared between the groups, as well as the associations of number of oral bacteria with Charlson comorbidity index (CCI)-related diseases in regard to mortality and disease severity. There was no significant difference in hospital stay length between the low (24.3 ± 24.2 days) and high (22.8 ± 20.1 days) oral bacterial number groups. On the other hand, the daily hospital medical cost in the high group was significantly greater (US$1456.2 ± 1505.7 vs. US$1185.7 ± 1128.6, P < 0.001). Additionally, there was no significant difference in CCI score between the groups, whereas the daily hospital medical costs for patients in the high group treated for cardiovascular disease or malignant tumors were greater than in the low number group (P < 0.05). Multivariate regression analysis was also performed, which showed that oral bacterial number, age, gender, BMI, cardiovascular disease, diabetes, malignant tumor, and hospital stay length were independently associated with daily hospitalization costs. Monitoring and oral care treatment to lower the number of oral bacteria in patients affected by cardiovascular disease or cancer may contribute to reduce hospitalization costs.

Effects of Smoking on Regional Homogeneity in Mild Cognitive Impairment: A Resting-State Functional MRI Study

Background

Smoking is a modifiable risk factor for Alzheimer’s disease (AD). However, smoking-related effects on intrinsic brain activity in high-risk AD population are still unclear.

Objective

We aimed to explore differences in smoking effects on brain function between healthy elderly and amnestic mild cognitive impairment (aMCI) patients using ReHo mapping.

Methods

We identified 64 healthy elderly controls and 116 aMCI patients, including 98 non-smoking and 18 smoking aMCI. Each subject underwent structural and resting-state functional MRI scanning and neuropsychological evaluations. Regional homogeneity (ReHo) mapping was used to assess regional brain synchronization. After correction for age, gender, education, and gray matter volume, we explored the difference of ReHo among groups in a voxel-wise way based on analysis of covariance (ANCOVA), followed by post hoc two-sample analyses (p < 0.05, corrected). Further, we correlated the mean ReHo with neuropsychological scales.

Results

Three groups were well-matched in age, gender, and education. Significant ReHo differences were found among three groups, located in the left supramarginal gyrus (SMG) and left angular gyrus (AG). Specifically, non-smoking aMCI had lower ReHo in SMG and AG than smoking aMCI and controls. By contrast, smoking aMCI had greater AG ReHo than healthy controls (p < 0.05). Across groups, correlation analyses showed that left AG ReHo correlated with MMSE (r = 0.18, p = 0.015), clock drawing test (r = 0.20, p = 0.007), immediate recall (r = 0.36, p < 0.001), delayed recall (r = 0.34, p < 0.001), and auditory verbal learning test (r = 0.20, p = 0.007).

Conclusion

Smoking might pose compensatory or protective effects on intrinsic brain activity in aMCI patients.

Epithelial-mesenchymal transition and GALC expression of circulating tumor cells indicate metastasis and poor prognosis in non-small cell lung cancer

BACKGROUND

Circulating tumor cells (CTCs) is a promising biomarker for cancer prognosis and monitoring. Molecular characterizing of CTCs could provide beneficial information on the basis of CTCs counting.

OBJECTIVE

To investigate the epithelial-mesenchymal transition (EMT) phenotypes and GALC mRNA expression of CTCs in non-small cell lung cancer (NSCLC) patients.

METHODS

We analyzed the baseline number, EMT classification, and GALC expression of CTCs in 47 NSCLC patients using CanPatrol platform and RNA in situ hybridization technique.

RESULTS

CTCs were detected in 91.5% patients ranging 0-47/5 mL blood. Increased CTCs were associated with advanced tumor stages (6/5 mL) compared with early stages (3.5/5 mL). Patients with effective treatment response presented lower CTCs (3.5/5 mL) than patients with insufficient response (7/5 mL). Epithelial, hybrid and mesenchymal CTCs were detected in 55.4%, 78.7% and 61.7% patients, respectively. Patients with distant metastasis and poor curative outcomes presented higher level of EMT-CTCs. GALC expression was positive in CTCs of 80.6% patients and closely correlated with tumor number and distant metastasis and treatment outcomes.

CONCLUSIONS

EMT phenotypes and GALC expression of CTCs are correlated with cancer metastasis and therapeutic outcomes, suggesting them to be potential markers for the prognosis of NSCLC.

Screening and Early Detection of Lung Cancer

OBJECTIVE

To review current risk factors for lung cancer, identify screening and early detection guidelines while describing new approaches that use genomic technologies.

DATA SOURCES

Published scientific literature, clinical literature, and published lung cancer screening guidelines from the United States and Canada.

CONCLUSION

Nurses are caring for lung cancer patients who, historically, do not live for long periods after diagnosis. Research is revealing promising screening methodologies that can detect lung cancer 1 to 4 years earlier than the current approaches.

IMPLICATIONS FOR NURSING PRACTICE

Current knowledge about screening for lung cancer is a vital tool for nurses working with persons at high risk for this potentially aggressive and life-threatening malignancy. While old methods remain the standard of care, new detection methods use a variety of genomic-based technologies. These developing approaches emphasize the need for nurses at all levels of practice to have a working knowledge of genetics to educate patients and conference with colleagues.

Familial Lung Cancer: A Brief History from the Earliest Work to the Most Recent Studies

Lung cancer is the deadliest cancer in the United States, killing roughly one of four cancer patients in 2016. While it is well-established that lung cancer is caused primarily by environmental effects (particularly tobacco smoking), there is evidence for genetic susceptibility. Lung cancer has been shown to aggregate in families, and segregation analyses have hypothesized a major susceptibility locus for the disease. Genetic association studies have provided strong evidence for common risk variants of small-to-moderate effect. Rare and highly penetrant alleles have been identified by linkage studies, including on 6q23-25. Though not common, some germline mutations have also been identified via sequencing studies. Ongoing genomics studies aim to identify additional high penetrance germline susceptibility alleles for this deadly disease.

PICT1 expression is a poor prognostic factor in non-small cell lung cancer

PICT1 is a key regulator of the MDM2–TP53 pathway. High mRNA expression levels of PICT1 are associated with poor prognosis in several cancers with wild-type TP53. In this study, we identified the PICT1 protein expression profile in non-small cell lung cancer (NSCLC) with wild-type TP53 in the nucleolus and cytoplasm, and revealed the relationship between PICT1 expression and patient clinicopathological factors. PICT1 expression in the tumor cells of 96 NSCLC patients with wild-type TP53 was evaluated by immunohistochemistry. Forty-three of 96 (44.8%) NSCLC samples were positive for nucleolar PICT1, while 40/96 (41.7%) NSCLC samples were positive for cytoplasmic PICT1. There was no correlation between nucleolar PICT1 expression and clinicopathological factors. However, cytoplasmic PICT1 expression was significantly correlated with sex, smoking history, differentiation, lymphatic invasion and pathological stage. In multivariate analysis, lymphatic invasion was significantly associated with cytoplasmic PICT1 expression (hazard ratio: 5.02, P = 0.026). We scrutinized PICT1 expression in samples of NSCLC with wild-type TP53, and showed a correlation between cytoplasmic PICT1 expression and several clinicopathological factors in these patients. Our results indicate that cytoplasmic PICT1 expression is a poor prognostic factor and is associated with tumor progression via lymphatic invasion in these patients.

Association between smoking and p53 mutation in lung cancer: a meta-analysis

AIMS

To carry out a meta-analysis on the relationship between smoking and p53 gene mutation in lung cancer patients.

MATERIALS AND METHODS

PubMed, Web of Science, ProQest and Medline were searched by using the key words: 'lung cancer or lung neoplasm or lung carcinoma', 'p53 mutation' and 'smoking'. According to the selection criteria, 15 articles were identified and methodologically analysed by stata 12.0 software package. Crude odds ratios with 95% confidence intervals calculated using the fixed-effects model were used to assess the strength of association between smoking and p53 mutation in lung cancer.

RESULTS

In total, 15 articles with 1770 lung cancer patients were identified; 69.6% of the patients were smokers, 30.4% were non-smokers. Overall, smokers with lung cancer had a 2.70-fold (95% confidence interval 2.04-3.59) higher risk for mutation than the non-smokers with lung cancer. In subgroup analyses, the increased risk of p53 mutation in smokers than in non-smokers was found in the non-small cell lung cancer (NSCLC) group (odds ratio = 2.38, 95% confidence interval = 1.71-3.32) and in the NSCLC and SCLC group (odds ratio = 3.82, 95% confidence interval = 2.19-6.69).

CONCLUSIONS

This meta-analysis strongly suggests that p53 mutation is associated with smoking-induced lung cancer. Smokers with lung cancer had a higher risk for p53 mutation than non-smokers.

Cigarette-Smoke-Induced Dysregulation of MicroRNA Expression and Its Role in Lung Carcinogenesis

Dysregulation of microRNAs (miRNAs), particularly their downregulation, has been widely shown to be associated with the development of lung cancer. Downregulation of miRNAs leads to the overactivation of their oncogene targets, while upregulation of some miRNAs leads to inhibition of important tumor suppressors. Research has implicated cigarette smoke in miRNA dysregulation, leading to carcinogenesis. Cigarette smoke may lead to genetic or epigenetic damage to miRNAs, many of which map to fragile sites and some of which contain single nucleotide polymorphisms. Cigarette smoke may also cause dysregulation by affecting regulatory mechanisms controlling miRNA expression. Researchers have shown a correlation between smoke-exposure-induced dysregulation of miRNAs and age. Furthermore, dysregulation seems to be associated with intensity and duration of smoke exposure and duration of cessation. Longer exposure at a threshold level is needed for irreversibility of changes in expression. Better understanding of miRNA dysregulation may allow for improved biomonitoring and treatment regimens for lung cancer.

TP53 mutations in nonsmall cell lung cancer

The tumor suppressor gene TP53 is frequently mutated in human cancers. Abnormality of the TP53 gene is one of the most significant events in lung cancers and plays an important role in the tumorigenesis of lung epithelial cells. Human lung cancers are classified into two major types, small cell lung cancer (SCLC) and nonsmall cell lung cancer (NSCLC). The latter accounts for approximately 80% of all primary lung cancers, and the incidence of NSCLC is increasing yearly. Most clinical studies suggest that NSCLC with TP53 alterations carries a worse prognosis and may be relatively more resistant to chemotherapy and radiation. A deep understanding of the role of TP53 in lung carcinogenesis may lead to a more reasonably targeted clinical approach, which should be exploited to enhance the survival rates of patients with lung cancer. This paper will focus on the role of TP53 in the molecular pathogenesis, epidemiology, and therapeutic strategies of TP53 mutation in NSCLC.

Relationship between TP53 tumour suppressor gene mutations and smoking-related bulky DNA adducts in a lung cancer study population from Hungary

Lung cancer rate in Hungary is one of the highest in the world among men and also very high among women, for reasons not clearly understood yet. The aim of the study was to explore characteristics of DNA damage and TP53 gene mutations in lung cancer from Hungary. Tissue samples from 104 lung resections for lung cancer patients, both men and women, operated on for non-small cell lung cancer, specifically, primary squamous cell carcinoma or adenocarcinoma were studied. Of the cases, 37% smoked up to the surgery, 24% stopped smoking within 1 year before the surgery, 26% stopped smoking more than a year before the surgery and 13% never smoked. TP53 mutations were detected by denaturant gradient gel electrophoresis, automated capillary electrophoresis single-strand conformation polymorphism and sequencing. Bulky DNA adduct levels were determined by (32)P-post-labelling in non-tumorous lung tissue. In total, 45% (47/104) of the cases carried TP53 mutation. The prevalence of TP53 mutations was statistically significantly associated with duration of smoking, tumour histology and gender. Smokers had approximately twice as high bulky adduct level as the combined group of former- and never-smokers (10.9 +/- 6.5 versus 5.5 +/- 3.4 adducts/10(8) nucleotides). The common base change G --> T transversion (8/43; 19%) was detected exclusively in smokers. For the first time, we demonstrate that most carriers of G --> T transversions had also a high level of bulky DNA adducts in their non-tumourous lung tissue. Our study provides evidence for a high burden of molecular alterations occurring concurrently in the lung of lung cancer patients.

Molecular genetics of lung cancer in people who have never smoked

Lung cancer is a major cause of cancer-related mortality in the USA, and tobacco smoke is the major risk factor for this disease. However, many patients with lung cancer have never smoked (never smokers). Patients with lung cancer who have never smoked are more likely to have mutations in epidermal growth factor receptor (EGFR) tyrosine kinase and have better response to its inhibitors than do patients with tobacco-associated lung cancer. Furthermore, the prevalences of mutations in KRAS and P53 differ for patients with lung cancer who have never smoked and those with tobacco-associated lung cancer. Genetic mutations seem to be more common in patients with tobacco-associated lung cancer than in never smokers. Current evidence indicates that the two types of lung cancer are biologically distinct. Here, we review published studies of the molecular genetics of lung cancer in never smokers and identify the specific differences from tobacco-associated lung cancer.

Combined antioxidant (beta-carotene, alpha-tocopherol and ascorbic acid) supplementation increases the levels of lung retinoic acid and inhibits the activation of mitogen-activated protein kinase in the ferret lung cancer model

Interactions among beta-carotene (BC), alpha-tocopherol (AT) and ascorbic acid (AA) led to the hypothesis that using a combination of these antioxidants could be more beneficial than using a single antioxidant alone, particularly against smoke-related lung cancer. In this investigation, we have conducted an animal study to determine whether combined BC, AT and AA supplementation (AOX) protects against 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK)-induced lung carcinogenesis in smoke-exposed (SM) ferrets. Ferrets were treated for 6 months in the following four groups: (i) control, (ii) SM + NNK, (iii) AOX and (iv) SM + NNK + AOX. Results showed that the combined AOX supplementation (i) prevented the SM + NNK-decreased lung concentrations of retinoic acid (RA) and BC; (ii) inhibited the SM + NNK-induced phosphorylation of Jun N-terminal kinase (JNK), extracellular-signal-regulated protein kinase (ERK) and proliferating cellular nuclear antigen proteins in the lungs of ferrets; and (iii) blocked the SM + NNK-induced up-regulation of total p53 and Bax proteins, as well as phosphorylated p53 in the lungs of ferrets. In addition, there were no lesions observed in the lung tissue of ferrets in the control and/or the AOX groups after 6 months of intervention, but combined AOX supplementation resulted in a trend toward lower incidence of both preneoplastic lung lesions and lung tumor formation in SM + NNK + AOX group of ferrets, as compared with the SM + NNK group alone. These data indicate that combined AOX supplementation could be a useful chemopreventive strategy against lung carcinogenesis through maintaining normal tissue levels of RA and inhibiting the activation of mitogen-activated protein kinase pathways, cell proliferation and phosphorylation of p53.

TP53 and KRAS mutation load and types in lung cancers in relation to tobacco smoke: distinct patterns in never, former, and current smokers

TP53 mutations are common in lung cancers of smokers, with high prevalence of G:C-to-T:A transversions generally interpreted as mutagen fingerprints of tobacco smoke. In this study, TP53 (exons 5-9) and KRAS (codon 12) were analyzed in primary lung tumors of never (n = 40), former (n = 27), and current smokers (n = 64; mainly heavy smokers). Expression of p53, cyclooxygenase-2 (Cox-2), and nitrotyrosine (N-Tyr), a marker of protein damage by nitric oxide, were analyzed by immunohistochemistry. TP53 mutations were detected in 47.5% never, 55.6% former, and 77.4% current smokers. The relative risk for mutation increased with tobacco consumption (P(linear trend) < 0.0001). G:C-to-T:A transversions (P = 0.06, current versus never smokers) and A:T-to-G:C transitions (P = 0.03, former versus never smokers) were consistently associated with smoking. In contrast, G:C-to-A:T transitions were associated with never smoking (P = 0.02). About half of mutations in current smokers fell within a particular domain of p53 protein, suggesting a common structural effect. KRAS mutations, detected in 20 of 131 (15.3%) cases, were rare in squamous cell carcinoma compared with adenocarcinoma [relative risk (RR), 0.2; 95% confidence interval (95% CI), 0.07-1] and were more frequent in former smokers than in other categories. No significant differences in Cox-2 expression were found between ever and never smokers. However, high levels of N-Tyr were more common in never than ever smokers (RR, 10; 95% CI, 1.6-50). These results support the notion that lung tumorigenesis proceeds through different molecular mechanisms according to smoking status. In never smokers, accumulation of N-Tyr suggests an etiology involving severe inflammation.

Genotoxicity of environmental tobacco smoke: a review

Environmental tobacco smoke (ETS), or second-hand smoke, is a widespread contaminant of indoor air in environments where smoking is not prohibited. It is a significant source of exposure to a large number of substances known to be hazardous to human health. Numerous expert panels have concluded that there is sufficient evidence to classify involuntary smoking (or passive smoking) as carcinogenic to humans. According to the recent evaluation by the International Agency for Research on Cancer, involuntary smoking causes lung cancer in never-smokers with an excess risk in the order of 20% for women and 30% for men. The present paper reviews studies on genotoxicity and related endpoints carried out on ETS since the mid-1980s. The evidence from in vitro studies demonstrates induction of DNA strand breaks, formation of DNA adducts, mutagenicity in bacterial assays and cytogenetic effects. In vivo experiments in rodents have shown that exposure to tobacco smoke, whole-body exposure to mainstream smoke (MS), sidestream smoke (SS), or their mixture, causes DNA single strand breaks, aromatic adducts and oxidative damage to DNA, chromosome aberrations and micronuclei. Genotoxicity of transplacental exposure to ETS has also been reported. Review of human biomarker studies conducted among non-smokers with involuntary exposure to tobacco smoke indicates presence of DNA adducts, urinary metabolites of carcinogens, urinary mutagenicity, SCEs and hypoxanthine-guanine phosphoribosyltransferase (HPRT) gene mutations (in newborns exposed through involuntary smoking of the mother). Studies on human lung cancer from smokers and never-smokers involuntarily exposed to tobacco smoke suggest occurrence of similar kinds of genetic alterations in both groups. In conclusion, these overwhelming data are compatible with the current knowledge on the mechanisms of carcinogenesis of tobacco-related cancers, occurring not only in smokers but with a high biological plausibility also in involuntary smokers.

Lung cancer risk in germline p53 mutation carriers: association between an inherited cancer predisposition, cigarette smoking, and cancer risk

We recently observed a significantly increased risk for lung cancer in carriers of p53 germline mutations. Because cigarette smoking is known to play an important role in increasing the risk for lung cancer in the general population, we wanted to determine the role of cigarette smoking in lung cancer risk in people with a genetic susceptibility based on a p53 germline mutation. We studied 1263 people from 97 families enrolled in a cohort study of families systematically ascertained through childhood soft-tissue sarcoma patients treated at the M.D. Anderson Cancer Center, University of Texas, between 1944 and 1975. We assessed the incidence of lung and smoking-related cancers in 33 carriers of germline p53 mutations and in 1,230 noncarriers to determine whether there was an association between an inherited cancer predisposition, cigarette smoking, and cancer risk. We analyzed the association between cigarette smoking, mutation status, and lung and other smoking-related cancers by the Kaplan-Meier method and the Cox proportional hazards model with adjustments for birth year, race, and sex. In the hazards model, we incorporated a robust variance estimation to adjust for familial correlation. We observed an increased risk of a variety of histological types of lung cancer in the carriers of the p53 germline mutation. Mutation carriers who smoked had a 3.16-fold (95% confidence interval =1.48-6.78) higher risk for lung cancer than the mutation carriers who did not smoke. Our results demonstrate that cigarette smoking significantly increases lung cancer risk in carriers of a germline p53 mutation. This finding could be useful in designing strategies for early detection and treatment of lung and smoking-related cancers in individuals with this inherited cancer predisposition.

Clinical implication of p53 mutation in lung cancer

Lung cancer development involves multiple genetic abnormalities leading to malignant transformation of the bronchial epithelial cells, followed by invasion and metastasis. One of the most common changes is mutation of the p53 tumor suppressor gene. The frequency of p53 alterations in lung cancer is highest in small cell and squamous cell carcinomas. A genetic "signature" of the type of p53 mutations has been associated with carcinogens in cigarette smoke. The majority of clinical studies suggest that lung cancers with p53 alterations carry a worse prognosis, and may be relatively more resistant to chemotherapy and radiation. An understanding of the role of p53 in human lung cancer may lead to more rational targeted approaches for treating this disease. P53 gene replacement is currently under clinical investigation but clearly more effective means of gene deliver to the tumor cells are required. Novel approaches to lung cancer therapy are needed to improve the observed poor patient survival despite current therapies.

Molecular epidemiology of smoking and lung cancer

Lung cancer is the single most common cause of death, and almost all of it is due to tobacco smoking. Before the widespread use of cigarettes in this century, lung cancer was a rare illness. Tobacco smoke is a complex mixture of numerous mutagens and carcinogens. Over the last 40 years, the type of cigarettes most frequently used has been changing, namely the increased use of low tar and nicotine cigarettes. This has been accompanied by an increased risk of lung cancer due to a smokers' need to maintain blood nicotine levels, which in turn causes the need for smoking more cigarettes per day and deeper inhalation. This phenomena has led to the increasing rates of lung adenocarcinoma, compared to squamous cell carcinoma. It also probably explains, in part, the greater risk of lung cancer in women compared to men (in addition to some biological differences). The study of lung cancer involves many types of biomarkers, including those that measure exposure, the biologically effective dose and harm. The use of these has allowed us to understand many parts of lung carcinogenesis. Genetic susceptibilities play a large role in lung cancer risk. They govern smoking behavior (affecting dopamine reward mechanisms due to nicotine and nicotine metabolism), carcinogen metabolism and detoxification, DNA repair, cell cycle control and other cellular responses. The need for the study of lung cancer is highlighted by the need to improve cessation rates and reduce exposure among persons who cannot quit smoking, for better prevention strategies for former smokers and an understanding of environmental tobacco smoke risk.

The significance of immunohistochemistry in the diagnosis and therapy of neoplasms

This review article details the diagnostical significance of immunohistochemistry, which has developed during the last quarter of the century. Certainly, the advancement of monoclonal antibody technology has been of great significance in assuring the place of immunohistochemistry in the modern accurate microscopic diagnosis of human neoplasms, as a method of choice in histopathology. The fact still remains that in order to properly assess any immunohistochemical reactivity used for differential diagnostic purposes, the target cells have to be identified as neoplastically transformed cells by routine histopathological techniques. Selected groups of target molecules of great significance in cancer biology are discussed. The discovery of neoplasm-associated antigens has not only made the more accurate diagnosis of human cancer feasible but has also shed light on the extensive immunophenotypical heterogeneity of even the most closely linked human malignancies. The identification of disseminated neoplastically transformed cells by immunohistochemistry has allowed for a clearer picture of cancer invasion and metastasis, as well as the evolution of the tumour cell associated immunophenotype towards increased malignancy. Some possibilities of neoplasm-associated antigen targeted, receptor-directed immunotherapy are discussed and reviewed in this manuscript. Future antineoplastic therapeutical approaches should see the inclusion of a variety of immunotherapies, in the form of an individualised 'cocktail' specific for the particular immunophenotypical pattern associated with each individual patient's neoplastic disease.

Serum sialyl Lewis X-i antigen in lung adenocarcinoma and idiopathic pulmonary fibrosis

BACKGROUND

Sialyl Lewis X-i antigen has been used as a diagnostic tool for lung adenocarcinoma. However, serum levels of the antigen are also raised in some patients with idiopathic pulmonary fibrosis (IPF) without coexistent malignancy. Expression of the antigen in serum samples of patients with lung adenocarcinoma was evaluated and compared with that of patients with IPF by Western blotting in order to establish a specific laboratory test to differentiate lung adenocarcinoma from IPF.

METHODS

The pattern of antigen expression in serum samples from 23 patients with either lung adenocarcinoma or non-malignant lung disease in whom serum levels of sialyl Lewis X-i antigen (>50 U/ml) were significantly increased was studied by Western blotting.

RESULTS

Thirteen of the 14 serum samples from patients with lung adenocarcinoma had a molecular weight band at 120 or 130 kD, while five of the six patients with IPF had two or three bands at <97.4 kD. The pattern of antigen expression was apparently different between the two diseases. The sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio of this test in 20 patients with lung adenocarcinoma and IPF were 92.9%, 83.3%, 5.57, and 0.09, respectively.

CONCLUSIONS

Western blotting analysis of serum samples from patients with raised levels of sialyl Lewis X-i antigen provides some clinical information for a differential diagnosis between lung adenocarcinoma and IPF.

Frequent microsatellite instability in lung cancer from chromate-exposed workers

Although chromium has been the most extensively investigated metal with respect to mutagenicity and carcinogenicity, its genetic effects in humans are only partly understood. Our previous study demonstrated that lung cancer from chromate-exposed workers infrequently (20%) displayed p53 gene mutations as well as a particular mutation pattern. In the present study, we examined the replication error (RER) and loss of heterozygosity (LOH) in 38 lung cancers from 28 chromate-exposed workers (chromate lung cancer group) and in 26 lung cancer patients without chromate exposure (non-chromate lung cancer group), using six microsatellite markers containing CA repeats: D3S647 (3p23), D3S966 (3p21.3), D3S1289 (3p21.1), D5S346 (5q21-q22), D9S161 (9p21), and TP53 (17p13.1). The RER phenotype was defined as the presence of microsatellite instability (MSI) at two or more loci. Thirty (78.9%) of 38 tumors in the chromate lung cancer group exhibited RER. In contrast, only four (15.4%) of 26 tumors in the non-chromate lung cancer group exhibited RER. The frequency of RER in the chromate lung cancer group was significantly higher than that in the non-chromate lung cancer group (P < 0.0001). By contrast, the frequency of LOH at 3p, 5q, 9p, and 17p loci in tumors with chromate exposure was not significantly different from that in tumors without chromate exposure. In the chromate lung cancer group, the period of chromate exposure in workers with RER (24.5 +/- 6.7 yr) was significantly longer than that in workers without RER (17.0 +/- 3.5 yr) (P = 0.0046). In addition, a longer period of chromate exposure was associated with a tendency toward a higher frequency of MSI. This finding suggests that MSI may play a role in chromium-induced carcinogenesis. In addition to our previous study of p53 mutations, the present findings suggest that the carcinogenic mechanism of chromate lung cancer may differ from that of non-chromate lung cancer.

Cigarette smoking and rheumatoid arthritis

OBJECTIVES

To examine and explore the potential relationships among the following: the incidence/severity of rheumatoid arthritis (RA), the extra-articular manifestations of RA, vascular disease, certain specific malignancies, the p53 tumor suppressor gene, and cigarette smoking.

METHODS

The medical literature was reviewed from 1985 to 2001 with the assistance of a MEDLINE search using the key words vascular disease, smoking, protein p53, RA, rheumatoid vasculitis, cancer, and malignancies. A qualitative review was performed after all articles were abstracted and new information summarized.

RESULTS

Cigarette smoking has been increasingly shown in epidemiologic and case-control studies to be an important risk factor for both the incidence and severity of RA, especially in seropositive men. Further, there is evidence of a downward trend in incidence of extra-articular manifestations of RA, especially RA vasculitis, observed with a decrease in worldwide tobacco use and overall improved mortality in RA. The association of cigarette smoking with lung and other cancers and its link to vascular disease (including Buerger's disease) and atherosclerosis appears secure. Mutations or alterations in p53, a suppressor gene that regulates cell growth, have been found in certain cancers, cigarette smokers, and in patients with RA.

CONCLUSIONS

Cigarette smoking appears to have an undeniable link to the pathogenesis of vascular disease of many types, including the possibility of a strong causal connection to rheumatoid vasculitis. The observations worldwide of decreasing tobacco use along with secular trends of diminished RA vasculitis and extra-articular manifestations, and with improved survival, points to a better outcome for our patients. The example of p53 may be a first step in the discovery of additional links between environmental triggers and phenotypic expression of chronic illness.

Role of p53 as a prognostic factor for survival in lung cancer: a systematic review of the literature with a meta-analysis

The role of p53, as a prognostic factor for survival in lung cancer, is controversial and the purpose of the present systematic review of the literature is to determine this effect. Published studies were identified with the objective to aggregate the available survival results after a methodological assessment using a scale specifically designed by the European Lung Cancer Working Party (ELCWP). To be eligible, a study had to deal with p53 assessment in lung cancer (primary site) only, and to provide a survival comparison according to the p53 status. Among the 74 eligible papers, 30 identified p53 abnormalities as a univariate statistically significant poor prognostic factor and 56 provided sufficient data to allow survival results aggregation. There was no significant difference between the trials that either showed or did not show a prognostic effect of p53 according to the methodological score or to the laboratory technique used. The studies were categorized by histology, disease stage, treatment and laboratory technique. Combined hazard ratios suggested that an abnormal p53 status had an unfavourable impact on survival: in any stage nonsmall cell lung cancer (NSCLC) the mean (95% confidence interval) was 1.44 (1.20-1.72) (number of studies included in the subgroup was 11), 1.50 (1.32-1.70) in stages I-II NSCLC (n=19), 1.68 (1.23-2.29) in stages I-IIIB NSCLC (n=5), 1.68 (1.30-2.18) in stages III-IV NSCLC (n=9), 1.48 (1.29-1.70) in surgically resected NSCLC (n=20), 1.37 (1.02-1.85) in squamous cell carcinoma (n=9), 2.24 (1.70-2.95) in adenocarcinoma (n=9), 1.57 (1.28-1.91) for a positive immunohistochemistry with antibody 1801 (n=8), 1.25 (1.09-1.43) for a positive immunohistochemistry with antibody DO-7 (n=16), and 1.65 (1.35-2.00) for an abnormal molecular biology test (n=13). Data were insufficient to determine the prognostic value of p53 in small cell lung cancer. In each subgroup of nonsmall cell lung cancer, p53 abnormal status was shown to be associated with a poorer survival prognosis.

Assessment of smoking related risks for respiratory symptoms among elderly people

Disease risk among elderly smokers is considered to be doubled due to their smoking habits and age as compared with elderly non-smokers. The investigators conducted risk assessments of smoking for respiratory symptoms among elderly people.A questionnaire survey on smoking habits and respiratory symptoms was conducted among 3,000 persons of 56 years of age and over who were randomly selected from suburban residents in a prefecture in Japan in October, 1997. A total 1,954 or 65.1%, of individuals responded, consisting of 42.8% for men and 57.2% for women, with an average age of 73.6 years.In addition to descriptive analysis, multiple logistic regression analysis was conducted. The results are summarized as follows: Smokers accounted for 28.1% of men and 3.6% of women. Among all age-groups, the highest rate of smokers was observed in men of 56-69 years old (34.7%) which was lower than the national average rate for the 60-69 year-old group (56.1% of men and 14.5% of women in '97). The odds ratios and 95 percent confidence interval (95%CI) for "having phlegm every day" and "having phlegm for more than 4 days a week" among smokers were 2.06 (95%CI=1.41-3.01) and 2.77(95%CI=1.80-4.27). Significantly higher odds ratios among smokers were also observed for "wheezing" and "shortness of breath when hurrying".Odds ratios for some respiratory symptoms including "having phlegm for more than 4 days per week" among inhalers were significantly high compared with non-smokers, whereas those among non-inhalers were not significantly different from 1.0. Odds ratios for symptoms of phlegm and wheezing were significantly higher (Odds ratio≥2.0) among heavy smokers (Brinkman Index [B.1] >900) compared to non-smokers, while odds ratios of the same symptoms were not different from 1.0 among light smokers (B. I. ≤500).

A study of smoking, p53 tumor suppressor gene alterations and non-small cell lung cancer

PURPOSE

The purpose of this study was to investigate the relationship between smoking and p53 tumor suppressor gene alterations, and their association with clinicopathologic features and prognosis in non-small cell lung cancer (NSCLC).

METHODS

For 111 of 119 stage I-III NSCLC patients that had been followed prospectively, tumor p53 protein accumulation was measured immunohistochemically (IHC). Staining was evaluated as a score (p53IHCS) combining intensity and percent distribution.

RESULTS

Forty-eight of 111 (43%) tumors had p53IHCS > 1. p53 IHC was associated with increasing tumor size (T) (p = 0.035), nodal status (N) (p = 0.091), stage (p = 0.054), and histology: squamous cell carcinoma (70%) and adenocarcinoma (27%) (p = 0.0002). In logistic regression analysis, p53 IHC was associated with squamous cell histology versus other histotypes [adjusted odds ratio (OR)5.90, 95% confidence interval (CI) 2.34-14.90]. p53 IHC was not associated with smoking variables. In multivariate proportional hazards analysis, p53IHCS and pack-years smoked (PY), both as continuous variables, were negative prognostic factors. The adjusted hazard ratios (HR) for the survival outcome recurrence for p53IHCS and PY were 1.20 (95% CI 1.02-1.40) and 1.03 (95% CI 1.01-1.04), and for death due to recurrent disease (DRD) were 1.35 (95% CI 1.11-1.64) and 1.03 (95% CI 1.01-1.04), respectively. Comparing the 75th percentile to the baseline 0, the adjusted HR for p53IHCS (5 vs. 0) was 4.5 and for PY (55 vs. 0) was 5.1 for the outcome DRD. Both variables demonstrated a dose-response relationship with survival.

CONCLUSIONS

PY and p53IHCS are significant, independent and important predictors of recurrence and DRD in stage I-III NSCLC.

Molecular epidemiological study of non-small-cell lung cancer from an environmentally polluted region of Poland

The p53 mutation spectrum can generate hypotheses linking carcinogen exposure to human cancer. Although it is well-documented that tobacco smoking is a major cause of lung cancer, the contribution of air pollution is less well-established. We determined the molecular and immunohistochemical changes (p53 gene mutations, p53 protein accumulation and WAF1 protein expression) and genetic polymorphisms of GSTM1, CYP1A1 and CYP2D6 genes in a case series of non-small-cell lung cancers from Silesia. This region of southern Poland is highly industrialized with considerable environmental pollution. More than 50% of lung cancers (90/164) contained p53 mutations and 75% showed the combined alteration of the p53 gene and protein accumulation. Males occupationally exposed to coal-derived substances showed a relatively high frequency of squamous and large-cell carcinomas, relatively frequent mutations in codon 298 of p53 and a low frequency of p53 immunohistochemically positive tumours. Codon 298 GAG-->TAG mutations have rarely been found in lung cancers in other populations. We found no correlation between WAF1 protein expression and mutations in the p53 gene or p53 protein accumulation. No statistically significant relationship was found between p53 mutations and GSTM1, CYP1A1, CYP2D6 genotypes. Never smokers with lung cancers from Silesia had a higher frequency of G:C-->T:A transversions than previously reported of the p53 mutation spectrum in never smokers (6/15 vs 4/34; P = 0.06 by chi2). These data are a tentative indication that occupational and environmental exposure to polycyclic aromatic hydrocarbons, such as benzo(a)pyrene, in polluted air contributes to the molecular pathogenesis of lung cancer in never smokers.

Correlates of occasional cigarette and marijuana use: are teens harm reducing?

This paper examines characteristics that distinguish heavy and occasional cigarette and marijuana use among U.S. high school seniors. High school seniors who completed the 1994 Monitoring the Future survey (N = 15,929) were classified as nonusers, occasional users, and heavy users of cigarettes and marijuana. Level of use was examined with regard to degree of perceived risk of regular use, perceived risk of occasional use as well as several psychosocial factors previously shown to be associated with use (e.g., peer use, close friends' approval of use, and self-esteem). Involvement with other drugs and high-risk behaviors across levels of use was also examined. Heavy users of cigarettes or marijuana reported significantly lower perceived risk of regular use of each substance compared to occasional users. Heavy and occasional users did not generally differ with regard to perceived risk of occasional use. Compared to heavy users, occasional cigarette or marijuana users reported significantly lower rates of illicit drug use, heavy alcohol use, and high-risk driving behaviors as well as fewer problem behaviors and higher grades. Some adolescents may moderate their cigarette and marijuana use to minimize harmful effects they associate with heavier use (i.e., they may be practicing harm reduction). Additional research is needed to better understand controlled substance use, and incorporate this information into prevention and cessation programs.

High frequency expressions of CD44 standard and variant forms in non-small cell lung cancers, but not in small cell lung cancers

BACKGROUND AND OBJECTIVES

Organ specificity has been demonstrated in the mode of CD44 expression among several cancers.

METHODS

We examined the expressions of CD44 standard (CD44s) and CD44 variants (CD44v) in 14 cell lines (small cell lung cancer (SCLC): 5, non-small cell lung cancer (NSCLC): 9 and 20 surgically resected samples (SCLC: 7, NSCLC: 13) of lung cancer using reverse transcription polymerase chain reaction and immunohistochemistry.

RESULTS

Although both NSCLC and SCLC expressed CD44s, the frequency and intensity of CD44s expression in NSCLC were different from those in SCLC: cell lines, 89% vs. 40%; tumor samples, 100% (diffusely stained) vs. 57% (focally stained). CD44s expression was partially or completely repressed in SCLC. However, NSCLC frequently expressed CD44v, but SCLC expressed infrequently: cell lines, 67% vs. 20%; tumor samples, 69% vs. 0%. The N-417 line, which only expressed some CD44v in SCLC, falls SCLC and NSCLC both in biomarkers and in growth patterns.

CONCLUSIONS

CD44 expression was repressed in SCLC but was enhanced in NSCLC.

A specific spectrum of p53 mutations in lung cancer from smokers: review of mutations compiled in the IARC p53 database

Mutations in the p53 gene are common in lung cancer. Using data from the the International Agency for Research on Cancer p53 mutation database (R1), we have analyzed the distribution and nature of p53 mutations in 876 lung tumors described in the literature. These analyses confirm that G to T transitions are the predominant type of p53 mutation in lung cancer from smokers. The most frequently mutated codons include 157, 158, 179, 248, 249, and 273, and several of them (157, 248, and 273) have been shown to correspond to sites of in vitro DNA adduct formation by metabolites of polycyclic aromatic hydrocarbons (PAHs) such as benzo(a)pyrene. Furthermore, most of the base changes at codons 248, 249, and 273 in lung cancer differ from those commonly observed at these codons in other cancers reported in the database. Thus, lung cancer from smokers shows a distinct, unique p53 mutation spectrum that is not observed in lung cancer from nonsmokers. These results further strengthen the association between active smoking, exposure to PAHs, and lung cancer. They also indicate that a different pattern of mutations occurs in nonsmokers, and this observation may help to identify other agents causally involved in lung cancer in nonsmokers.

IARC Database of p53 gene mutations in human tumors and cell lines: updated compilation, revised formats and new visualisation tools

Since 1989, about 570 different p53 mutations have been identified in more than 8000 human cancers. A database of these mutations was initiated by M. Hollstein and C. C. Harris in 1990. This database originally consisted of a list of somatic point mutations in the p 53 gene of human tumors and cell lines, compiled from the published literature and made available in a standard electronic form. The database is maintained at the International Agency for Research on Cancer (IARC) and updated versions are released twice a year (January and July). The current version (July 1997) contains records on 6800 published mutations and will surpass the 8000 mark in the January 1998 release. The database now contains information on somatic and germline mutations in a new format to facilitate data retrieval. In addition, new tools are constructed to improve data analysis, such as a Mutation Viewer Java applet developed at the European Bioinformatics Institute (EBI) to visualise the location and impact of mutations on p53 protein structure. The database is available in different electronic formats at IARC (http://www.iarc. fr/p53/homepage.htm ) or from the EBI server (http://www.ebi.ac.uk ). The IARC p53 website also provides reports on database analysis and links with other p53 sites as well as with related databases. In this report, we describe the criteria for inclusion of data, the revised format and the new visualisation tools. We also briefly discuss the relevance of p 53 mutations to clinical and biological questions.

Mutation spectra resulting from carcinogenic exposure: from model systems to cancer-related genes

The events leading to cancer are complex and interactive. Alteration of cancer genes, such as the tumor suppressor gene p53, plays a central role in this process. Analysis of the frequency, type and site of mutations in important cancer-related genes may provide clues to the identification of etiological factors and sources of exposure. In this chapter we have selected a few examples of environmental human carcinogens and have attempted to use the knowledge of their mechanisms of mutagenesis, as derived from in vitro cell systems, as a key to understanding the complexity of p53 mutation spectra in tumors arising at the putative target organ. The analysis will focus on environmental exposure to UV radiation. The examples of tobacco smoke, dietary aflatoxin and vinyl chloride will be also briefly discussed.

Mutations, tissue accumulations, and serum levels of p53 in patients with occupational cancers from asbestos and silica exposure

In order to determine the relationship between mutations, tissue accumulations, and serum levels of p53 in occupational cancers, we used denaturing gradient gel electrophoresis and DNA sequencing of exons 5-9 of the p53 gene, immunohistochemical analysis for tissue identification of mutant p53 protein, and enzyme-linked immunosorbent assay for serum levels of mutant p53 protein to examine for such alteration in a cohort of individuals with workplace exposure to asbestos or silica, and resultant lung cancers or mesotheliomas. DNA analysis detected mutations in 5 of 18 (28%) tumors, and tissue accumulations of protein were detected in 7 of 20 (35%) tumors; the agreement between mutational and immunohistochemical analyses was significant (kappa = 0.62, P = 0.002). Serum elevations of protein were detected in 4 of 11 (36%) cases with available serum samples; the agreement between tissue alterations and serum elevations was also significant (kappa = 0.71, P = 0.017). In addition, based on the analysis of banked samples, serum results tended to be consistent over time prior to the diagnosis of disease (positive predictive value = 0.67, negative predictive value = 0.83). These results suggest that serum levels of p53 are reasonably accurate in reflecting tissue alterations in p53 at the gene and/ or protein level and may be early biomarkers of disease risk.