Epidemiology of lung cancer: looking to the future

Infrequent hypermethylation of the PTEN gene in Korean non-small-cell lung cancers

CpG islands (CGIs) hypermethylation is implicated in the pathogenesis of many cancers, including lung cancer. The phosphate and tension homolog (PTEN) is a tumor suppressor that controls a variety of biological processes including cell proliferation, growth, migration, and death. The defects in PTEN regulation have a profound impact on carcinogenesis. Herein, we have examined the methylation status of the human PTEN gene in 137 primary non-small-cell lung cancers (NSCLCs) by using a methylation-specific PCR and correlated the results with clinicopathological features. Promoter methylation of the PTEN gene was observed in 5.1%, 2.9%, and 0.0% of three different CpG regions, which were localized at -1460 to -1263, -984 to -848, and -300 to -128 nucleotides upstream of the translation start site, respectively. Reverse transcription-PCR and immunohistochemical analysis showed the methylation of the CGI region at -984 to -848 correlated more accurately with PTEN expression. In addition, no significant correlation was found between PTEN methylation and clinicopathological factors, including the survival rates. These findings suggest that promoter methylation is not an important mechanism for PTEN deregulation in NSCLCs from Koreans.

Smoking is associated with shortened airway cilia

Background

Whereas cilia damage and reduced cilia beat frequency have been implicated as causative of reduced mucociliary clearance in smokers, theoretically mucociliary clearance could also be affected by cilia length. Based on models of mucociliary clearance predicting that cilia length must exceed the 6–7 µm airway surface fluid depth to generate force in the mucus layer, we hypothesized that cilia height may be decreased in airway epithelium of normal smokers compared to nonsmokers.

Methodology/Principal Findings

Cilia length in normal nonsmokers and smokers was evaluated in aldehyde-fixed, paraffin-embedded endobronchial biopsies, and air-dried and hydrated samples were brushed from human airway epithelium via fiberoptic bronchoscopy. In 28 endobronchial biopsies, healthy smoker cilia length was reduced by 15% compared to nonsmokers (p<0.05). In 39 air-dried samples of airway epithelial cells, smoker cilia length was reduced by 13% compared to nonsmokers (p<0.0001). Analysis of the length of individual, detached cilia in 27 samples showed that smoker cilia length was reduced by 9% compared to nonsmokers (p<0.05). Finally, in 16 fully hydrated, unfixed samples, smoker cilia length was reduced 7% compared to nonsmokers (p<0.05). Using genome-wide analysis of airway epithelial gene expression we identified 6 cilia-related genes whose expression levels were significantly reduced in healthy smokers compared to healthy nonsmokers.

Conclusions/Significance

Models predict that a reduction in cilia length would reduce mucociliary clearance, suggesting that smoking-associated shorter airway epithelial cilia play a significant role in the pathogenesis of smoking-induced lung disease.

Are adenosquamous lung carcinomas a simple mix of adenocarcinomas and squamous cell carcinomas, or more complex at the molecular level?

Adenocarcinomas (AC), squamous cell carcinomas (SCC) and adenosquamous carcinomas (ASC) are three histological subtypes of non-small-cell lung carcinomas (NSCLC). ASC are morphologically mixed tumours that contain the two cell components AC and SCC. To understand if they are a "simple" mix of AC and SCC or if they present molecular specificities, as compared with the molecular characterization of both components, we performed a comparative transcriptome analysis on a series of nine ASC, five AC and five SCC induced in rats by radon exposure. We found that 72, 40 and 39 genes were differentially expressed when comparing AC_SCC, ASC_SCC and AC_ASC, respectively. Moreover, when classifying the three histological subtypes, using genes that discriminated AC and SCC, we observed that all ASC were classified as intermediate between the AC and SCC, some being closer to AC, others to SCC. These results indicated that, regarding gene expression, ASC could be considered as a mix of AC and SCC, both in various proportions. However, they also exhibit molecular specificities since we found specific genes discriminating ASC_SCC and AC_ASC. In conclusion, the ASC mixed lung tumours are more complex than simple mixes of AC and SCC components. Neuroendocrine differentiation and ERK proliferation pathways seemed preferentially deregulated in ASC compared to AC and SCC respectively, pathways that are worthy of being explored because they could partially explain the high clinical aggressiveness of ASC.

TP53 Arg72Pro polymorphism and lung cancer risk: a meta-analysis

No clear consensus has been reached on the TP53 Arg72Pro polymorphism (G12139C) and lung cancer risk. Thus, a meta-analysis was conducted to summarize the possible association. There was no statistical association between 12139C (Pro allele) and lung cancer risk in Caucasians compared with 12139G allele. However, the association was observed in all subjects (9,387 patients and 9,922 controls, p=0.04, OR=1.08, 95% CI 1.00-1.17), as well as in Asians (p=0.0004, OR=1.14, 95% CI 1.06-1.22). The association was also found in Asians under recessive genetic model (p<0.00001, OR=1.37, 95% CI 1.20-1.57) and homozygote comparison (CC vs. GG) (p<0.0001, OR=1.34, 95% CI 1.16-1.56). 12139C allele might increase the lung adenocarcinoma risk compared with 12139G allele (p=0.01, OR=1.11, 95% CI 1.02-1.21), and the effect was also found under recessive genetic model (p=0.003, OR=1.28, 95% CI 1.09-1.50) and homozygote comparison (CC vs. GG) (p=0.007, OR=1.28, 95% CI 1.07-1.52). There was an elevated association between the 12139C and the stage I lung cancer under dominant genetic model (p=0.04, OR=1.48, 95% CI 1.02-2.16), but no association was observed in other stages. No association of smoking was found between 12139C allele and lung cancer under recessive genetic model. Our result indicated that 12139C might increase the risk of lung cancer under recessive genetic model in adenocarcinoma, in Asians, and in lung cancer stage I. More studies stratified for lung cancer stage-genotyping interaction should be performed to clarify the role of TP53 Arg72Pro polymorphism in the development of lung cancer.

Psychological impact of computed tomography screening for lung cancer and occupational pulmonary disease among asbestos-exposed workers

The objective of this study was to investigate the psychological impact of screening for lung cancer and occupational pulmonary disease among asbestos-exposed workers. Altogether, 633 workers were screened with chest computed tomography (627 men, 6 women, mean age 64.5 years). Participants' views on the necessity of screening,awareness of asbestos-exposure risks, their perceived lung cancer risk, trial adherence intention, health anxiety,and worry about lung cancer were assessed. Health anxiety was reduced significantly after screening (P < 0.001). After 1 year, no significant long-term psychological differences were found between those who immediately received clear results and those who were submitted to additional examinations because of positive findings. In conclusion,computed tomography screening of pulmonary disease was well accepted and did not produce excessive long-term anxiety or other negative psychological effects,which could prevent the participation in the future screening programs.

Up-regulation of RAGE and S100A6 in rats exposed to cigarette smoke

Cigarette smoke has been widely investigated in terms of epidemiology and pathological endpoints in relation to human lung diseases and animal study. In this study we exposed Wistar rats to cigarette smoke at concentrations of 20% and 60% to explore potential molecular mechanisms at the protein level. Exposures were conducted twice a day, 5 days a week for 43 weeks. As a major metabolite of nicotine in cigarette, cotinine level in rat urine was determined by HPLC-MS. A dose-dependent analysis indicated that cotinine may be used as an exposure marker of cigarette smoke. Expression of receptor for advanced glycation endproducts (RAGE), an immunoglobulin super family that triggers the intracellular signal cascade reaction leading to inflammation and its ligand S100A6 (calgranulin) in bronchial epithelial cells and lung tissues of rats, were found to be positive correlated with cotinine levels, indicating that RAGE and S100A6 may be attributable to inflammation and oxidative damage caused by cigarette smoke.

Lung cancer in a health area of Spain: incidence, characteristics and survival

To examine the incidence, characteristics, therapeutic approach and survival of diagnosed lung cancer (LC) in the Santiago de Compostela Health Area. A retrospective study was carried out on LC for a period of 3 years. Of the 481 cases collected, 92.7% were male. The median age was 66.93 years. The crude incidence for men and women was 80.71 and 5.84 per 100,000 inhabitants respectively. Among the non-small cell lung cancers (NSCLC), 68.1% were diagnosed in stage IIIB or IV. The cancer had already spread in 62.2% of the small cell lung cancer (SCLC). Chemotherapy was used in 51.6% of patients. The survival probability from the first to the fifth year was 47.7%, 24.3%, 12.9%, 10% and 8.9% respectively. The median survival at 5 years was 12.12 months for NSCLC, rising to 29.8 months in stage I, and 8.85 months in SCLC. In our Health Area LC occurs more often in men, in whom the prevalence of smoking is very high. The most common histology type was squamous cell carcinoma. In the majority of cases, the diagnosis is made in the advanced stages, which accounts for the low percentage of surgical treatments and the short survival.

Geographical clustering of lung cancer in the province of Lecce, Italy: 1992-2001

Background

The triennial mortality rates for lung cancer in the two decades 1981–2001 in the province of Lecce, Italy, are significantly higher than those for the entire region of Apulia (to which the Province of Lecce belongs) and the national reference rates. Moreover, analyzing the rates in the three-year periods 1993–95, 1996–98 and 1999–01, there is a dramatic increase in mortality for both males and females, which still remains essentially unexplained: to understand the extent of this phenomenon, it is worth noting that the standardized mortality rate for males in 1999–01 is equal to 13.92 per 10000 person-years, compared to a value of 6.96 for Italy in the 2000–2002 period.

These data have generated a considerable concern in the press and public opinion, which with little scientific reasoning have sometimes identified suspected culprits of the risk excess (for example, the emission caused by a number of large industrial sites located in the provinces of Brindisi and Taranto, bordering the Province of Lecce). The objective of this paper is to study on a scientifically sound basis the spatial distribution of risk for lung cancer mortality in the province of Lecce. Our goal is to demonstrate that most of the previous explanations are not supported by data: to this end, we will follow a hybrid approach that combines both frequentist and Bayesian disease mapping methods. Furthermore, we define a new sequential algorithm based on a modified version of the Besag-York-Mollié (BYM) model, suitably modified to detect geographical clusters of disease.

Results

Standardized mortality ratios (SMRs) for lung cancer in the province of Lecce: For males, the relative risk (measured by means of SMR, i.e. the ratio between observed and expected cases in each area under internal standardization) was judged to be significantly greater than 1 in many municipal areas, the significance being evaluated under the null hypothesis of neutral risk on the ground of area-specific p-values (denoted by ρ_i); in addition, it was seen that high risk areas were not randomly distributed within the province, but showed a sharp clustering. The most perceptible cluster involved a collection of municipalities around the Maglie area (Istat code: 75039), while the association among the municipalities of Otranto, Poggiardo and Santa Cesarea Terme (Istat codes: 75057, 75061, 75072) was more ambiguous. For females, it was noteworthy the significant risk excess in the city of Lecce (Istat code: 75035), where an SMR of 1.83 and ρ_i < 0.01 have been registered. BYM model for the province of Lecce: For males, Bayes estimates of relative risks varied around an overall mean of 1.04 with standard deviation of 0.1, with a minimum of 0.77 and a maximum of 1.25. The posterior relative risks for females, although smoothed, showed more variation than for males, ranging form 0.74 to 1.65, around a mean of 0.90 with standard deviation 0.12. For males, 95% posterior credible intervals of relative risks included unity in every area, whereas significantly elevated risk of mortality was confirmed in the Lecce area for females (95% posterior CI: 1.33 – 2.00). BYM model for the whole Apulia: For males, internally standardized maps showed several high risk areas bordering the province of Lecce, belonging to the province of Brindisi, and the presence of a large high risk region, including the southern part of the province of Brindisi and the eastern and southern part of the Salento peninsula, in which an increasing trend in the north-south direction was found.

Ecological correlation study with deprivation (Cadum Index): For males, posterior mean of the ecological regression coefficient β resulted to be 0.04 with 95% posterior credible interval equal to (-0.01, 0.08); similarly, β was estimated as equal to -0.03 for females (95% posterior credible interval: -0.16, 0.10). Moreover, there was some indication of nonlinearly increasing relative risk with increasing deprivation for higher deprivation levels. For females, it was difficult to postulate the existence of any association between risk and deprivation.

Cluster detection: cluster detection based on a modified BYM model identified two large unexplained increased risk clusters in the central-eastern and southern part of the peninsula. Other secondary clusters, which raise several complex interpretation issues, are present.

Conclusion

Our results reduce the alleged role of the industrial facilities located around the province of Taranto: in particular, air pollution produced around the city of Taranto (which lies to the west of the province of Lecce) has been often identified as the main culprit of the mortality excess, a conclusion that was further supported by a recent study on the direction of prevailing winds on Salento. This hypothesis is contradicted by the finding that those municipalities that directly border on the province of Taranto (belonging to the so-called "Jonico-Salentina" band) are those that present low mortality rates (at least for males). In the same way, the responsibilities of energy production plants located in the province of Brindisi (Brindisi province lies to the north) appear to be of little relevance. For females, given the situation observed in the city of Lecce, and given the substantial increase in mortality observed in younger age classes, further investigation is required into the role played by changes in lifestyle, including greater net propensity to smoke that women have shown since the 80s onwards (a phenomenon which could be amplified in a city traditionally cultured and modern as Lecce, as the tobacco habit is a largely cultural phenomenon). For males, the presence of high levels of deprivation throughout the eastern and southern Salento is likely to play an important role: those with lower socio-economic status smoke more, and gender differences may be explained on the basis of the fact that in less developed areas women have less habit to tobacco smoking and alcohol drinking (and other harmful lifestyles), which are seen as purely masculine behaviour: research into the role of material deprivation and individual lifestyle differences between genders should be further developed.

Expression of a mutant p53 results in an age-related demographic shift in spontaneous lung tumor formation in transgenic mice

Background

Mutations in the P53 gene are among the most common genetic abnormalities in human lung cancer. Codon 273 in the sequence-specific DNA binding domain is one of the most frequently mutated sites.

Methodology

To investigate the role of mutant p53 in lung tumorigenesis, a lung specific p53(273H) transgenic mouse model was developed. Rates of lung cancer formation in the transgenic animals and their littermates were evaluated by necropsy studies performed in progressive age cohorts ranging from 4 to 24 months. In order to establish the influence of other common genetic abnormalities in lung tumor formation in the animals, K-Ras gene mutation and p16INK4a (p16) promoter methylation were evaluated in a total of 281 transgenic mice and 189 non-transgenic littermates.

Principal Findings

At the age extremes of 4–12 and 22–24 months no differences were observed, with very low prevalence of tumors in animals younger than 12 months, and a relatively high prevalence at age 22 months or older. However, the transgenic mice had a significant higher lung tumor rate than their non-transgenic counterparts during the age of 13–21 months, suggesting an age-related shift in lung tumor formation induced by the lung-specific expression of the human mutant p53. Histopathology suggested a more aggressive nature for the transgenic tumors. Older mice (>13 months) had a significantly higher rate of p16 promoter methylation (17% v 82%). In addition, an age related effect was observed for K-Ras codons 12 or 13 mutations, but not for codon 61 mutations.

Conclusions/Significance

These results would suggest that the mutant p53(273H) contributes to an acceleration in the development of spontaneous lung tumors in these mice. Combination with other genetic and epigenetic alterations occurring after the age of 13 months is intimately linked to its oncogenic potential.

How cigarette smoke skews immune responses to promote infection, lung disease and cancer

A complex and multilayered immune defence system protects the host against harmful agents and maintains tissue homeostasis. Cigarette smoke exposure markedly impacts the immune system, compromising the host's ability to mount appropriate immune and inflammatory responses and contributing to smoking-related pathologies. These adverse effects on the immune system not only occur in active smokers, but also in those exposed to smoke passively in contaminated environments, and may persist for decades after exposure has ended.

Lifestyle Interventions in the Prevention and Treatment of Cancer

Despite evidence that cancer death rates in the United States are declining, the absolute number of new cancers and cancer deaths continues to increase, and there is clear evidence that certain human behaviors are influencing these increases. The 4 major factors of lifestyle that continue to be causally related to certain cancers—tobacco use, an unhealthy diet, inadequate exercise, and excessive exposure to ultraviolet radiation—are each independently important in their effects on the genetic and molecular processes that result in the malignant transformation of human cells. There is both irrefutable and otherwise strong evidence that 4 common cancers that occur in the United States—lung cancer, colon/rectal cancer, breast cancer, and prostate cancer—and a less common cancer, malignant melanoma, have etiologic factors that are lifestyle based and therefore controllable through alterations in human behavior. These cancers and the evidence that lifestyle is important in the causation and/or prevention of the disease are the subjects of this review.

Epigenetic inactivation of checkpoint kinase 2 gene in non-small cell lung cancer and its relationship with clinicopathological features

Lung cancer is the leading cause of cancer deaths worldwide and is usually associated with late diagnosis and poor prognosis. Tumor-acquired methylation of the promoter CpG islands (CGIs) is an important mechanism for silencing tumor suppressor genes. The checkpoint kinase 2 (CHK2) is a tumor suppressor that plays a crucial role in regulating cell-cycle checkpoints and apoptosis following DNA damage. The methylation statuses of two CGIs, distal and proximal, of human CHK2 gene were determined in non-small cell lung cancers (NSCLCs) using a nested methylation-specific PCR and bisulfite sequencing. The methylation of distal CHK2 CGI was found in 39 (28.1%) of the 139 NSCLCs. Its frequency was significantly more frequent in squamous cell carcinomas than in adenocarcinomas (40.0% vs 19.0%, p=0.006) and was also higher in ever-smokers than in never-smokers with a borderline significance (31.7% vs 17.1%, p=0.071). RT-PCR analysis showed that the distal CGI methylation correlated with CHK2 mRNA expression. However, the methylation of the proximal CHK2 CGI is not specific to tumors and not related to gene expression. These results suggest that the down-regulation of CHK2 gene via distal CGI methylation may play a role in the pathogenesis of NSCLC, particularly squamous cell carcinoma. However, further studies with large numbers of patients are needed to confirm our findings.

Long-term use of beta-carotene, retinol, lycopene, and lutein supplements and lung cancer risk: results from the VITamins And Lifestyle (VITAL) study

High-dose beta-carotene supplementation in high-risk persons has been linked to increased lung cancer risk in clinical trials; whether effects are similar in the general population is unclear. The authors examined associations of supplemental beta-carotene, retinol, vitamin A, lutein, and lycopene with lung cancer risk among participants, aged 50-76 years, in the VITamins And Lifestyle (VITAL) cohort Study in Washington State. In 2000-2002, eligible persons (n = 77,126) completed a 24-page baseline questionnaire, including detailed questions about supplement use (duration, frequency, dose) during the previous 10 years from multivitamins and individual supplements/mixtures. Incident lung cancers (n = 521) through December 2005 were identified by linkage to the Surveillance, Epidemiology, and End Results cancer registry. Longer duration of use of individual beta-carotene, retinol, and lutein supplements (but not total 10-year average dose) was associated with statistically significantly elevated risk of total lung cancer and histologic cell types; for example, hazard ratio = 2.02, 95% confidence interval: 1.28, 3.17 for individual supplemental lutein with total lung cancer and hazard ratio = 3.22, 95% confidence interval: 1.29, 8.07 for individual beta-carotene with small-cell lung cancer for >4 years versus no use. There was little evidence for effect modification by gender or smoking status. Long-term use of individual beta-carotene, retinol, and lutein supplements should not be recommended for lung cancer prevention, particularly among smokers.

Serum concentrations of cytokines and lung cancer survival in African Americans and Caucasians

Accumulating evidence suggests a role for inflammation in the development and progression of cancer. Our group recently identified a cytokine gene signature in lung tissue associated with lung cancer prognosis. Therefore, we hypothesized that concentrations of circulating cytokines in serum may be associated with lung cancer survival. Ten serum cytokines, namely, interleukin (IL)-1beta, IL-4, IL-5, IL-6, IL-8, IL-10, IL-12, granulocyte macrophage colony-stimulating factor, interferon (IFN)-gamma, and tumor necrosis factor-alpha, were assessed in 353 non-small cell lung cancer cases from a case-control study of lung cancer in the greater Baltimore, Maryland area. Cytokines were measured using an ultrasensitive electrochemiluminescence immunoassay. IL-6 serum concentrations (>or=4.0 pg/mL) were associated with significantly poorer survival in both African Americans [hazard ratio (HR), 2.71; 95% confidence interval (CI), 1.26-5.80] and Caucasians (HR, 1.71; 95% CI, 1.22-2.40). IL-10 (HR, 2.62; 95% CI, 1.33-5.15) and IL-12 (HR, 1.98; 95% CI, 1.14-3.44) were associated with lung cancer survival only in African Americans. Some evidence for an association of tumor necrosis factor-alpha levels with survival in Caucasians was observed, although these results were not significant. These hypothesis-generating findings indicate that selected serum cytokine concentrations are associated with lung cancer survival, and indicate that further research is warranted to better understand the mechanistic underpinnings of these associations.

Socioeconomic differences in lung cancer incidence: a systematic review and meta-analysis

OBJECTIVE

To investigate the associations between various socioeconomic indicators and lung cancer incidence.

METHODS

We searched PubMed and EMBASE databases for studies on socioeconomic position (SEP) and lung cancer incidence published through October 2007. Random-effect model was used to pool the risk estimates from the individual studies. We stratified the analysis by adjustment strategy to investigate the influence of smoking on socioeconomic gradient in lung cancer incidence.

RESULTS

Out of 3,288 citations, we identified 64 studies eligible for inclusion. Compared to the highest SEP level, we observed an overall increased risk in lung cancer incidence among people with low educational SEP (61%), low occupational SEP (48%), and low income-based SEP (37%). The negative social gradient for lung cancer incidence remained for most of the possible sets of pooled estimates obtained in subgroup analyses for occupational and educational SEP with less consistency for SEP based on income in studies adjusted and unadjusted for smoking. No evidence of publication bias was apparent.

CONCLUSION

Lung cancer incidence was associated with low educational, occupational, and income-based SEP. The association, adjusted or unadjusted for smoking, points out the importance of social position to be addressed in all discussions on cancer preventive measures.

Cigarette smoking and changing trends of lung cancer incidence by histological subtype among Chinese male population

We analyzed the time trends of lung cancer by histological subtype in Hong Kong during 1991-2005, and examined how the time trends were influenced by the effects of birth cohort and calendar period of diagnosis. Cancer incidence data were obtained from Hong Kong Cancer Registry and population data from Census and Statistics Department. Age-standardized incidence rates were computed by the direct method using WHO 1966 standard population as reference. Period and cohort effects were assessed by using two separate Poisson regression models adjusting for age. From 1991 to 2005, the incidence rates in Hong Kong Chinese males decreased steadily. The decline in overall lung cancer incidence rates was limited primarily to the decrease in squamous cell carcinoma, which could be explained by the decreasing trend of cigarette smoking. Adenocarcinoma had been the most predominant histological subtype all along. The relatively horizontal trend of adenocarcinoma and the lack of cohort effect implied the important roles of gene-environment interaction and/or the use of low-tar and filter tip cigarettes. Our study suggests that different histological subtypes may represent different disease entities with perhaps some distinct risk factors. The hypotheses generated from this ecological study will need confirmation by subsequent analytic studies.

Oral vinorelbine and cisplatin as induction chemotherapy and concomitant chemo-radiotherapy in stage III non-small cell lung cancer: final results of an international phase II trial

INTRODUCTION

Cisplatin in combination with vinorelbine has reported an optimal activity/tolerance ratio when used in combination with radiotherapy in locally advanced unresectable non-small cell lung cancer. The currently available oral formulation of vinorelbine should be easier to use assuming a similar activity profile. An international phase II trial with vinorelbine oral and cisplatin as induction followed by oral vinorelbine and cisplatin with concomitant radiotherapy was implemented to evaluate the efficacy in terms of objective response (OR) following this combination as primary end point and duration or response, progression-free survival, overall survival, and safety as secondary endpoints.

MATERIAL AND METHODS

The study included patients between 18 and 75 years, with histologically proven untreated locally advanced inoperable stage IIIA/IIIB (supraclavicular lymph nodes and pleural effusion excluded) non-small cell lung cancer, adequate bone marrow, hepatic and renal function, Karnofsky performance status >/=80%. Patients were treated with oral vinorelbine 60 mg/m day 1,8 cycle 1 and 80 mg/m day 1,8 cycle 2 (if no grade 3-4 toxicity) and cisplatin 80 mg/m day 1 every 3 weeks for 2 cycles as induction. Patients without progression received oral vinorelbine 40 mg/m day 1, 8 and cisplatin 80 mg/m day 1 every 3 weeks for 2 more cycles with radiotherapy 66 Gy in 6.5 weeks.

RESULTS

Patient and disease characteristics (n = 54) included: median age 57 years; female sex 24%; stage IIIA 48% and IIIB 52%; Squamous carcinoma 59%, Karnofsky performance status 100% (range, 80-100%) 50%, patients >/=5% weight loss at baseline 7%. Relative dose intensities of oral vinorelbine/cisplatin were 86%/93% and 97%/98% at induction and in combination with radiotherapy, respectively. Forty-one patients (76%) increased oral vinorelbine from 60 to 80 mg/m day during induction (reasons for nonescalation: hematological 7 patients, nonhematological 2 patients, error 4 patients). After two cycles of chemotherapy induction, the OR intent-to-treat in the 54 patients was 37%. Toxicities during induction were as follows: Neutropenia G3-4 (28%), Febrile Neutropenia (7%), nausea G3 (11%), vomiting G3-4 (9%), anorexia G3 (4%), diarrhea G4 (2%), constipation G3 (2%). Forty-seven out of 54 (87%) patients received concomitant chemo-radiotherapy.Median radiotherapy delivered dose was 66 Gy. Tolerance: 9% G3 Neutropenia; 4% G3 dysphagia/radiation; 2% G3 radiation dermatitis. Late pulmonary fibrosis was reported in one patient (1.8%). One month after completion of chemo-radiotherapy, the overall OR intent-to-treat in the 54 patients was 54% (95% CI: 40-67%). With a median follow-up of 37 months (95% CI: 34-41) the median progression-free survival and overall survival were: 12.5 (95% CI: 9.6-16.4) and 23.4 (95% CI: 17.6-29.8) months, respectively.

CONCLUSION

Oral vinorelbine in combination with cisplatin is an effective combination in stage IIIA/IIIB patients. The excellent tolerance profile allowed to complete concomitant chemo-radiotherapy in 87% of patients. Oral vinorelbine in combination with cisplatin is a new and promising option that facilitates the administration of concomitant chemo-radiotherapy with high rates of treatment completion.

The International Epidemiology of Lung Cancer: geographical distribution and secular trends

This review presents the latest available international data for lung cancer incidence, mortality and survival, emphasizing the established causal relationship between smoking and lung cancer. In 2002, it was estimated that 1.35 million people throughout the world were diagnosed with lung cancer, and 1.18 million died of lung cancer-more than for any other type of cancer. There are some key differences in the epidemiology of lung cancer between more developed and less developed countries. In more developed countries, incidence and mortality rates are generally declining among males and are starting to plateau for females, reflecting previous trends in smoking prevalence. In contrast, there are some populations in less developed countries where increasing lung cancer rates are predicted to continue, due to endemic use of tobacco. A higher proportion of lung cancer cases are attributable to nonsmoking causes within less developed countries, particularly among women. Worldwide, the majority of lung cancer patients are diagnosed after the disease has progressed to a more advanced stage. Despite advances in chemotherapy, prognosis for lung cancer patients remains poor, with 5-year relative survival less than 14% among males and less than 18% among females in most countries. Given the increasing incidence of lung cancer in less developed countries and the current lack of effective treatment for advanced lung cancers, these results highlight the need for ongoing global tobacco reform to reduce the international burden of lung cancer.

Cytoplasmic and nuclear maspin expression in lung carcinomas: an immunohistochemical study using tissue microarrays

Maspin, a serine protease inhibitor related to the serpin family, can inhibit invasion and metastasis of malignancies although direct evidence of the clinicopathologic significance of cytoplasmic relative to nuclear expression is limited. Here, maspin expression was examined on tissue microarrays containing lung carcinoma (n=155) and adjacent noncancerous tissue (n=20) and also 4 lung carcinoma cell lines (LC-1/Sq, LC-IF, PC-14, and AoI) by immunohistochemistry. Maspin expression was compared with clinicopathologic parameters of the tumors. Maspin expression showed positive nuclear staining in basal cells, LC-IF, and PC-14 cell lines, and also cytoplasmic immunoreactivity in secretory and ciliated cells, LC-1/Sq cell line. Cytoplasmic staining was the lowest in adenocarcinoma (AD) and the highest in squamous cell carcinoma as compared with other types of lung carcinoma (P<0.05), and positively correlated with expression of p53 and caspase-3 (P<0.05). The cytoplasmic one showed stronger immunoreactivity in male carcinoma patients than female ones (P<0.05). The nuclear maspin expression gradually increased through squamous cell carcinoma, AD, large cell carcinoma to small cell carcinoma (P<0.05) and was also positively associated with the levels of vascular epithelial growth factor and extracellular matrix metalloproteinase inducer expression (P<0.05). Kaplan-Meier analysis indicated that the cytoplasmic or nuclear maspin expression was not a good prognostic marker for lung carcinomas overall (P>0.05), but the cytoplasmic pattern pointed to good survival for AD cases (P<0.05). It was concluded that the cytoplasmic and nuclear expression patterns of maspin are involved in the cellular differentiation of normal lung tissue and the histogenesis of different lung carcinomas. The cytoplasmic maspin may play an important role in lung carcinomas by regulating apoptosis and thus is a favorable prognostic marker for AD patients, whereas the nuclear location may be linked to promotion of angiogenesis.

Lung cancer in women: histological type and patient age from 1985 to 2005

The aim of the study was to analyse changes in histological type and age of presentation in female lung cancer patients during a period of 20 years. The obtained results are compared with those available from the literature published in various parts of the world.

A linkage analysis of cigarette and alcohol consumption in an unselected Mexican American population

The use of alcohol and tobacco is highly prevalent. Studying the rate of consumption in a non-selected population could contribute to the elucidation of pathways involved in addiction or to the development of prevention programs. The San Antonio Family Heart Study has approximately 1,400 members with longitudinal data and did not select the proband with regard to exposure status. The goal of this study was to perform genome-wide linkage analysis of the rate of alcohol and cigarette consumption in a "normal" population. We used SOLAR to perform variance-components based analysis of the transformed maximal rate of consumption. Despite estimated heritabilities of 0.52 (P < 0.001) for cigarette and 0.39 (P < 0.001) for alcohol consumption, univariate linkage analyses produced only suggestive LOD scores, however the second suggestive linkage peak for the alcohol phenotype was present at 148 cM on chromosome 10, in the exact vicinity of the peak for the cigarette phenotype. In a bivariate analyses, the environmental correlation between alcohol and cigarette consumption was not significantly different from zero (rho(e) = -0.15, P = 0.18) and the overall genetic correlation was not different from zero (rho(g) = 0.16, P = 0.34). The results from the bivariate linkage analysis found a maximum LOD score of 3.82 (genome-wide P = 0.0054) at 151 cM on chromosome 10, at the location of the overlapping peaks from the univariate analyses.

Relationship between radiation pneumonitis and prognosis in patients with primary lung cancer treated by radiotherapy

Relationship between the grade of radiation pneumonitis (RP) and treatment outcome in lung cancer patients has not been clarified yet. The purpose of this study was to retrospectively evaluate the relationship in patients with primary lung cancer treated by radiotherapy. One hundred thirty-five patients who underwent definitive radiotherapy with known grade of RP were analyzed. RP was scored by using the Radiation Therapy Oncology Group (RTOG) acute radiation morbidity scoring criteria. Survival and local control data were analyzed in relation to the grade of RP. RP was grade 0 in 5 patients, grade 1 in 71, grade 2 in 39, grade 3 in 15 (11%), grade 4 in 0 and grade 5 in 5 (3.7%). There were no significant correlations between patient or tumor characteristics and grade of RP. Excluding 5 patients with grade 5 pneumonitis, survival rates were similar between those with grade 0 or 1 pneumonitis and those with grade 2 or 3. Also, there was no difference in survival between patients with grade 0-2 pneumonitis and those with grade 3. Local control rates were similar between the two groups. Grade of RP did not appear to be associated with prognosis when patients with grade 5 pneumonitis were excluded from analysis.

Survivin expression in normal human bronchial epithelial cells: an early and critical step in tumorigenesis induced by tobacco exposure

The inhibitor of apoptosis protein survivin is selectively expressed in tumor cells. The tobacco component nicotine increases the transcription of the survivin gene in non-small cell lung cancer cells. However, the role of survivin expression induced by tobacco component is not clear during lung carcinogenesis. We investigated the effects of the tobacco components nicotine and its related carcinogen 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) on survivin expression in normal human bronchial epithelial (NHBE) cells and examined the role of survivin in the malignant transformation of normal human bronchial epithelial (HBE) cells induced by these components. We found that survivin messenger RNA (mRNA) expression was detected in 41% (7 of 17) of bronchial brush specimens from heavy smokers. Nicotine and NNK increased survivin mRNA and protein expression levels in primary cultured NHBE cells and immortalized HBE cells. Bronchial epithelium in mice administered NNK also showed increased staining for survivin. Nicotine and NNK stimulated the Akt-mammalian target of rapamycin (mTOR) pathway in NHBE cells, leading to increased de novo synthesis of survivin protein. Induced survivin expression increased the survival potential of the cells, which was blocked by transfection with survivin-specific small interfering RNA (siRNA). siRNA-induced down-regulation of survivin expression also suppressed the tumorigenic potential of premalignant and malignant HBE cells exposed to the tobacco components. These findings suggest that NNK and nicotine induce survivin protein synthesis in NHBE cells by activating the Akt-mTOR pathway and thus blockade of the pathway effectively inhibits the tobacco-induced malignant transformation of HBE cells.

County lung cancer mortality: a decision tree model for control and prevention

OBJECTIVE

It is widely accepted that smoking prevalence and poverty predict the occurrence of lung cancer mortality. The question asked in the study was: What are the important factors for counties that are useful to public health professionals? We sought to provide an answer, using a recursive partitioning approach applied to county-level indicators.

METHODS

Classification and regression tree analysis is relatively unexplored for its utility in public health. Using available ecologic data, county lung cancer mortality was modeled by several predictor variables from a larger set of candidates. We constructed a tree on the basis of statistical software, R.

RESULTS

Seven groupings were defined. Not surprisingly, smoking prevalence was a major determiner of tree nodes, as were prior coronary heart disease mortality, poverty, and National Air Toxics Assessment excess cancer deaths estimates. Lung cancer mortality groupings ranged from 47 per 100000 in the best 2 groupings (leaves) to 85 per 100000 in the worst grouping of 52 local jurisdictions.

CONCLUSIONS

Ecologic data portrayed in a classification and regression tree have utility for spurring etiologic investigation, tracking county outcomes, developing policy at any governmental level, and guiding program design and management. Community by community, improvements are not yet at Healthy People 2010 targets. Individual communities may benefit through efforts to focus attention on aspects such as smoking levels, poverty, air quality, or region, highlighted by this analysis.

Socioeconomic inequalities in lung cancer mortality in 16 European populations

OBJECTIVES

This paper aims to describe socioeconomic inequalities in lung cancer mortality in Europe and to get further insight into socioeconomic inequalities in lung cancer mortality in different European populations by relating these to socioeconomic inequalities in overall mortality and smoking within the same or reference populations. Particular attention is paid to inequalities in Eastern European and Baltic countries.

METHODS

Data were obtained from mortality registers, population censuses and health interview surveys in 16 European populations. Educational inequalities in lung cancer and total mortality were assessed by direct standardization and calculation of two indices of inequality: the Relative Index of Inequality (RII) and the Slope Index of Inequality (SII). SIIs were used to calculate the contribution of inequalities in lung cancer mortality to inequalities in total mortality. Indices of inequality in lung cancer mortality in the age group 40-59 years were compared with indices of inequalities in smoking taking into account a time lag of 20 years.

RESULTS

The pattern of inequalities in Eastern European and Baltic countries is more or less similar as the one observed in the Northern countries. Among men educational inequalities are largest in the Eastern European and Baltic countries. Among women they are largest in Northern European countries. Whereas among Southern European women lung cancer mortality rates are still higher among the high educated, we observe a negative association between smoking and education among young female adults. The contribution of lung cancer mortality inequalities to total mortality inequalities is in most male populations more than 10%. Important smoking inequalities are observed among young adults in all populations. In Sweden, Hungary and the Czech Republic smoking inequalities among young adult women are larger than lung cancer mortality inequalities among women aged 20 years older.

CONCLUSIONS

Important socioeconomic inequalities exist in lung cancer mortality in Europe. They are consistent with the geographical spread of the smoking epidemic. In the next decades socioeconomic inequalities in lung cancer mortality are likely to persist and even increase among women. In Southern European countries we may expect a reversal from a positive to a negative association between socioeconomic status and lung cancer mortality. Continuous efforts are necessary to tackle socioeconomic inequalities in lung cancer mortality in all European countries.

Non-small cell lung cancer: epidemiology, risk factors, treatment, and survivorship

Lung cancer is the leading cause of cancer-related mortality not only in the United States but also around the world. In North America, lung cancer has become more predominant among former than current smokers. Yet in some countries, such as China, which has experienced a dramatic increase in the cigarette smoking rate during the past 2 decades, a peak in lung cancer incidence is still expected. Approximately two-thirds of adult Chinese men are smokers, representing one-third of all smokers worldwide. Non-small cell lung cancer accounts for 85% of all lung cancer cases in the United States. After the initial diagnosis, accurate staging of non-small cell lung cancer using computed tomography or positron emission tomography is crucial for determining appropriate therapy. When feasible, surgical resection remains the single most consistent and successful option for cure. However, close to 70% of patients with lung cancer present with locally advanced or metastatic disease at the time of diagnosis. Chemotherapy is beneficial for patients with metastatic disease, and the administration of concurrent chemotherapy and radiation is indicated for stage III lung cancer. The introduction of angiogenesis, epidermal growth factor receptor inhibitors, and other new anti-cancer agents is changing the present and future of this disease and will certainly increase the number of lung cancer survivors. We identified studies for this review by searching the MEDLINE and PubMed databases for English-language articles published from January 1, 1980, through January 31, 2008. Key terms used for this search included non-small cell lung cancer, adenocarcinoma, squamous cell carcinoma, bronchioalveolar cell carcinoma, large cell carcinoma, lung cancer epidemiology, genetics, survivorship, surgery, radiation therapy, chemotherapy, targeted therapy, bevacizumab, erlotinib, and epidermal growth factor receptor.

Increasing lung cancer incidence among Israeli Arab men reflects a change in the earlier paradox of low incidence and high smoking prevalence

Lung cancer in Israel has previously appeared to be less common than expected, relative to the prevalence of smoking. The objective is to examine trends in lung cancer rates and smoking prevalence in Israeli Arab and Jewish men compared with the United States. Age-adjusted lung cancer incidence and mortality rates in Israel were calculated for 1980-2004 using the National Cancer Registry, and compared with the United States' rates, on the basis of the Surveillance Epidemiology and End Results program. Smoking rates were obtained from national surveys carried out during the years 1970-2004. During the period 1980-2004, among Israeli Arab men, there was an increase in lung cancer incidence rates, particularly during 1990-2004, when they increased by 17.8%. During the latter period, the incidence of lung cancer among Israeli Jewish men and men in the United States declined by 5.2 and 22.8%, respectively. In 2003-2004, the age-adjusted smoking rates were 41.3 and 31.6% among Israeli Arab and Jewish men, respectively, and past smoking habits reflect higher rates among Arab men over the past three decades. The marked increase in the incidence of lung cancer among Israeli Arab men during the last decade, without any evidence of increased smoking prevalence, might reflect a gradual loss of some apparent protection in this subpopulation. The possible explanations are changes in lifestyle, particularly in dietary habits.

Proteomic alteration in lung tissue of rats exposed to cigarette smoke

Cigarette smoke has been widely investigated in terms of epidemiological and pathological studies in relation to human lung diseases. In this study, we conducted a proteomic analysis to characterize the differential protein expression in lung tissue of rats exposed to cigarette smoke. Wistar rats were exposed to cigarette smoke twice a day, 30 min each for 1, 2 and 4 months, respectively. The total protein of lung tissue was extracted for two-dimensional electrophoresis (2-DE) and analyzed with ImageMaster 2D Platinum software. A total of 28 differentially expressed proteins between the control and the smoke-exposed groups were screened and of which 18 were identified by matrix assistant laser desorption ion-top of flight-mass spectrometry (MALDI-TOF-MS) or MALDI- TOF-TOF analysis, revealing 10 up-regulated and 8 down-regulated proteins. The up-regulated expression of two proteins, receptor for advanced glycation endpoints (RAGE) and thioredoxin (Trx), were validated by immunoblotting and found to be consistent with the proteomic analysis. The results presented in this study demonstrate the identification of proteomic pattern as an early indicator of lung damages induced by cigarette smoke. The differentially expressed proteins may be applied as exposure biomarkers in future experimental as well as epidemiologic investigations upon confirmation by a greater sample size and more validate study design for the proteomic research.

Non-small cell lung cancer: epidemiology, risk factors, treatment, and survivorship

Lung cancer is the leading cause of cancer-related mortality not only in the United States but also around the world. In North America, lung cancer has become more predominant among former than current smokers. Yet in some countries, such as China, which has experienced a dramatic increase in the cigarette smoking rate during the past 2 decades, a peak in lung cancer incidence is still expected. Approximately two-thirds of adult Chinese men are smokers, representing one-third of all smokers worldwide. Non-small cell lung cancer accounts for 85% of all lung cancer cases in the United States. After the initial diagnosis, accurate staging of non-small cell lung cancer using computed tomography or positron emission tomography is crucial for determining appropriate therapy. When feasible, surgical resection remains the single most consistent and successful option for cure. However, close to 70% of patients with lung cancer present with locally advanced or metastatic disease at the time of diagnosis. Chemotherapy is beneficial for patients with metastatic disease, and the administration of concurrent chemotherapy and radiation is indicated for stage III lung cancer. The introduction of angiogenesis, epidermal growth factor receptor inhibitors, and other new anti-cancer agents is changing the present and future of this disease and will certainly increase the number of lung cancer survivors. We identified studies for this review by searching the MEDLINE and PubMed databases for English-language articles published from January 1, 1980, through January 31, 2008. Key terms used for this search included non-small cell lung cancer, adenocarcinoma, squamous cell carcinoma, bronchioalveolar cell carcinoma, large cell carcinoma, lung cancer epidemiology, genetics, survivorship, surgery, radiation therapy, chemotherapy, targeted therapy, bevacizumab, erlotinib, and epidermal growth factor receptor.

Estimation of mean sojourn time for lung cancer by chest X-ray screening with a Bayesian approach

Very few studies, particularly from oriental population, reported the progression of lung cancer from asymptomatic to symptomatic phase. The present study aimed to estimate mean sojourn time (MST) of lung cancer, an average duration period in which tumour can be asymptotically detected by chest X-ray (CXR), taking into account gender, smoking and histological type. Based on institutional cancer registry for lung cancer patients with prior non-diagnostic CXR (n=221), data were collected on demographic features, histology type, survival status, history of smoking, and asymptomatic or symptomatic status in light of chief complaint at diagnosis retrieved from medical records. The MST for the natural history of lung cancer underpinning a three-state Markov model was estimated with a Bayesian approach. The estimated MST for lung cancer was 5.51 months (95% credible interval: 4.04-7.12). Small cell lung carcinoma was even statistically significantly shorter MST than non-small cell lung carcinoma (3.01 (3-3.98) months vs. 6.07 (4.44-8.25) months). In parallel with literatures reporting tumour growth rate related to CXR and computed tomography (CT), the shorter mean sojourn time by using CXR estimated in our study strongly suggests that CT screening may be more effective in early detection of lung cancer in population-based screening.

Novel systemic therapies for small cell lung cancer

A diagnosis of small cell lung cancer (SCLC) today confers essentially the same terrible prognosis that it did 25 years ago, when common use of cisplatin-based chemotherapy began for this disease. In contrast to past decades of research on many other solid tumors, studies of combination chemotherapy using later generation cytotoxics and targeted kinase inhibitors have not had a significant impact on standard care for SCLC. The past few years have seen suggestions of incrementally improved outcomes using standard cytotoxics, including cisplatin-based combination studies of irinotecan and amrubicin by Japanese research consortia. Confirmatory phase III studies of these agents are ongoing in the United States. Antiangiogenic strategies are also of primary interest and are in late-phase testing. Several novel therapeutics, including high-potency small molecule inhibitors of Bcl-2 and the Hedgehog signaling pathway, and a recently discovered replication-competent picornavirus, have shown remarkable activity against SCLC in preclinical models and are currently in simultaneous phase I clinical development. Novel therapeutic approaches based on advances in understanding of the biology of SCLC have the potential to radically change the outlook for patients with this disease.

Telomere shortening is associated with poor prognosis and telomerase activity correlates with DNA repair impairment in non-small cell lung cancer

BACKGROUND AND PURPOSE

Telomere function and DNA damage response pathways are frequently inactivated in cancer. Moreover, some telomere-binding proteins have been implicated in DNA repair. The purpose of this work consists of evaluating the prognostic impact of telomere dysfunction and its relationship with DNA repair systems in non-small cell lung cancer (NSCLC).

PATIENTS AND METHODS

We analysed 83 NSCLCs and their corresponding control samples obtained from patients submitted to surgery. Telomere function was evaluated by determining telomerase activity and telomere length. DNA repair expression assays were established by using cDNA arrays containing 96 DNA-repair genes and by Real Time Quantitative PCR.

RESULTS

Our data indicated that telomere attrition was significantly associated with poor clinical outcome of patients (P=0.02), being this parameter a significant prognostic factor independent of tumour stage (P=0.012; relative risk=1.887; 95% CI: 1.147-3.102). DNA-repair gene expression studies showed down regulation of DCLRE1C and GTF2H1 and a clear FLJ10858 up regulation in tumour tissues, as compared to controls. In addition, a number of genes related to DNA-repair were significantly down regulated in tumours that reactivated telomerase (DCLRE1C, GTF2H1, PARP-3, MLH1, and TRF2).

CONCLUSIONS

Telomere shortening emerged as a poor clinical evolution parameter in NSCLC. Moreover, results from this work suggest a relationship between the loss of several DNA repair genes and telomerase activity, which may be of relevance in the pathogenesis of non-small lung cancer.

Targeted disruption of the galectin-3 gene results in decreased susceptibility to NNK-induced lung tumorigenesis: an oligonucleotide microarray study

PURPOSE

Galectin-3, a beta-galactoside-binding animal lectin is a multifunctional protein, which regulates cell growth, cell adhesion, cell proliferation, angiogenesis, and apoptosis, and in turn contributes to tumorigenesis and metastasis. The aim of this study was to clarify the role or related mechanisms of galectin-3 in lung carcinogenesis.

METHODS

We administrated 4-(methylnitrosamino)-1-(3-pyridyle)-1-butanone (NNK), a powerful chemical carcinogen into galectin-3 wild-type (gal3+/+) and galectin-3 knock-out (gal3-/-) CD1 mice by intraperitoneal injection, examined the expression status of 22,690 mouse genes of the NNK-induced tumors using Affymetrix GeneChip mouse expression 430 A arrays, and then analyzed functional network and gene ontology by Ingenuity Pathway Analysis. Real-time PCR was also employed to partially confirm the genechip data.

RESULTS

Compared with the gal3+/+ mice, the incidence of lung tumors was significantly low in gal3-/- mice after 32 weeks (28.6 vs 52.1%, P < 0.05). Pathway analysis indicated that galectin-3 up-regulated carcinogenesis-related genes (e.g. B-cell receptor, ERK/MAPK, and PPAR signalings) in normal condition, and lung cancer and NNK-induced gene expression associated with cellular growth (e.g. Wnt/beta-catenin signaling) or immunological disease (e.g. EGF and PDGF signalings) in lung carcinogenesis with or without the galectin-3 control, respectively.

CONCLUSION

Disrupted galectin-3 may attenuate the lung carcinogenesis due to its regulatory role in the B-cell receptor, ERK/MAPK, and PPAR signal pathways.

Almond consumption reduces oxidative DNA damage and lipid peroxidation in male smokers

Smoking increases the risk of several chronic diseases associated with elevated oxidative stress status. Almonds are a good source of antioxidant nutrients and may diminish smoking-related biomarkers of oxidative stress. We investigated whether almond consumption decreases biomarkers of oxidative stress in young male smokers. We conducted a randomized, crossover clinical trial with 60 healthy male soldiers (18-25 y) who were habitual smokers (5-20 cigarettes/d) and supplemented their diet with 84 g almonds or 120 g pork (to control for calories) daily for 4 wk with a 4-wk washout period between treatment periods. In addition, 30 healthy nonsmoking men were provided the same daily serving of pork as reference comparison. Blood and urine were collected and assessed for biomarkers of oxidative stress. Baseline values of urinary 8-hydroxy-deoxyguanosine (8-OHdG) and malondialdehyde (MDA) and peripheral lymphocyte DNA strand breaks were significantly higher by 185, 64, and 97% in smokers than nonsmokers, whereas activities of plasma superoxide dismutase (SOD), glutathione peroxidase (GPX), and catalase were significantly lower by 15, 10, and 9%, respectively. After the almond intervention, serum alpha-tocopherol, SOD, and GPX increased significantly in smokers by 10, 35, and 16%, respectively and 8-OHdG, MDA, and DNA strand breaks decreased significantly by 28, 34, and 23%. In smokers, after almond supplementation, the concentration of 8-OHdG remained significantly greater than in nonsmokers by 98%. These results suggest almond intake can enhance antioxidant defenses and diminish biomarkers of oxidative stress in smokers.

Prevalence and correlates of environmental tobacco smoke exposure among adolescents in Mongolia

OBJECTIVE

To estimate the prevalence and identify correlates of environmental tobacco exposure (ETS) among adolescents in Mongolia.

METHODS

A cross-sectional study was carried out in 2003 in Mongolia within the framework of the Global Youth Tobacco Survey. Information was obtained on exposure to Environmental tobacco smoke (ETS) in the home and outside home, parental and peer smoking. Demographic characteristics such as age and sex were also obtained. Data were analyzed to obtain frequencies of characteristics. Logistic regression analysis was conducted to assess the association between ETS and relevant predictor variables.

RESULTS

73.9% (71.6%-76.1%) males and 71.7% (69.7%-73.7%) females reported being exposed to ETS either in the home or elsewhere. The odds of exposure were 5.85 (3.83-8.92) if both parents were smokers, 3.65(3.10-4.30) if only father smoked and 6.54 (3.48-12.32) if only mother smoked. Older adolescents were more likely to be exposed to ETS than younger adolescents. Prevalence of exposure to ETS within the home was similar between males and females but males had a higher prevalence of exposure outside of the home than females (50.7% and 42.4% respectively (p < 0.001). Overall proportion of adolescents exposed to ETS in the home was higher than those exposed outside suggesting that domestic exposure was the main form of ETS among adolescents in Mongolia.

CONCLUSION

Exposure to environmental tobacco smoke is high among school going adolescents in Mongolia. Public health interventions aimed to reduce morbidity from tobacco among adolescents should also accord particular attention toward environmental tobacco smoke.

Association of EcoRI polymorphism of the metastasis-suppressor gene NME1 with susceptibility to and severity of non-small cell lung cancer

BACKGROUND

Human lung cancer cells with high metastatic potential show reduced expression of the metastasis-suppressor gene NME1. However, the biallelic EcoRI polymorphism of this gene has not been studied in lung cancer. With this allelic association study, we aimed to investigate the impact of polymorphisms of the NME1 gene on the susceptibility to and severity of non-small cell lung cancer (NSCLC).

METHODS

Through a case-control study design, genomic DNA samples of 255 NSCLC patients and 303 controls, who were age and sex-matched and recruited from the health check-up unit, were subjected to polymorphism analysis with polymerase chain reaction-restriction fragment length polymorphism technique. The validity of this technique was proven by direct sequencing of polymerase chain reaction products. Statistical analyses were conducted to explore the contribution of polymorphism of the metastasis-suppressor gene NME1 in the susceptibility to and severity of NSCLC.

RESULTS

Overall, the genotype frequencies of NME1 gene were significantly different between lung cancer patients and controls (p < 0.0001), and also different between patients with lung cancers of various stages (p < 0.0001). Logistic regression analysis revealed that higher odds ratios (ORs) for lung cancer were seen in patients homozygous (+/+) for variant allele (an OR of 4.02, 95% CI 2.39-6.76; p < 0.0001). Patients carrying a variant polymorphic homozygote (+/+) also had a tendency to advanced disease (p = 0.001).

CONCLUSION

A significant association between the polymorphisms of NME1 gene and the susceptibility to and severity of lung cancer was demonstrated.

Lung specific expression of a human mutant p53 affects cell proliferation in transgenic mice

The human mutant p53(273H) has been shown in vitro to have both dominant-negative and gain-of-function properties, as well as to retain partial DNA-binding and transcriptional activation functions. We have developed a line of transgenic mice in which the human mutant p53(273H) is expressed in a lung specific manner (p53 (+/+/TG)). Crossing of the transgenic mice with p53 knockout mice led to generate mice with various genetic backgrounds. To evaluate the influence of p53 mutants in cell proliferation in mice lung tissue, we analyzed cell proliferation rate by Bromodeoxyuridine (BrdU) labeling and by expression of proliferating cell nuclear antigen (PCNA). BrdU analysis showed a 3.7-fold increase in the number of BrdU positive cells in the (p53 (-/+/TG)) mice compared to the (p53 (-/+)) mice, whereas no difference was observed in proliferation rate in the p53 (-/-/TG) lungs as compared to p53 (-/-) lungs. After the mice were treated with gamma-irradiation, BrdU positive cells were absent from both the p53 (-/+/TG) and p53 (-/+) mice, whereas a decrease in the rate of cell proliferation occurred in p53 (-/-/TG) lungs as compared to p53 (-/-) lungs. Real time PCR results indicated that the p53(273H) mutant did not retain the function to activate expression of p21 (WAF1/CIP1) in the transgenic mice. The above results indicate that overexpression of the human mutant p53(273H) in vivo results in an increase in basal proliferation rate which requires the presence of wild type p53. Mutant p53(273H) may affect cell proliferation by interrupting murine endogenous p53 function.

Lung cancer in never smokers--a different disease

Although most lung cancers are a result of smoking, approximately 25% of lung cancer cases worldwide are not attributable to tobacco use, accounting for over 300,000 deaths each year. Striking differences in the epidemiological, clinical and molecular characteristics of lung cancers arising in never smokers versus smokers have been identified, suggesting that they are separate entities. This Review summarizes our current knowledge of this unique and poorly understood disease.

Lung Cancer Chemoprevention

BACKGROUND

Lung cancer is the most common cause of cancer death in the United States. Cigarette smoking is the main risk factor. Former smokers are at a substantially increased risk for lung cancer compared with lifetime never-smokers. Chemoprevention is the use of specific agents to reverse, suppress, or prevent the process of carcinogenesis. This article reviews the major agents that have been studied for chemoprevention.

METHODS

Articles of primary, secondary, and tertiary prevention trials were reviewed and summarized to obtain recommendations.

RESULTS

None of the phase III trials with the agents beta carotene, retinol, 13-cis-retinoic acid, alpha-tocopherol, N-acetylcysteine, or acetylsalicylic acid has demonstrated beneficial, reproducible results. For facilitating the evaluation of promising agents and for lessening the need for a large sample size, extensive time commitment, and expense, focus is now turning toward the assessment of surrogate end point biomarkers for lung carcinogenesis. With the understanding of important cellular signaling pathways, various inhibitors that may prevent or reverse lung carcinogenesis are being developed.

CONCLUSIONS

By integrating biological knowledge, more trials can be performed in a reasonable time frame. The future of lung cancer chemoprevention should entail the evaluation of single agents or combinations that target various pathways while working toward identification and validation of intermediate end points.

Location of lung carcinoma in relation to the smoking habit and gender

OBJECTIVE

To analyze the locations of lung carcinomas in relation to patient gender and smoking status.

METHODS

In order to test the hypothesis that lung carcinoma location (upper or lower lobe; left or right side) is correlated with smoking status and gender, we conducted a retrospective study of 697 patients with bronchogenic carcinoma treated at the Pulmonology-Oncology Outpatient Clinic of the Federal University of São Paulo.

RESULTS

We found that the bronchogenic carcinomas occurring in smokers were more frequently located in the upper lobes, whereas those occurring in nonsmokers were more frequently located in the lower lobes. In women, the neoplasms were more often seen in the lower lobes, especially in nonsmokers. Based on the available data, there were no differences in terms of the side affected (left or right).

CONCLUSION

Overall, bronchogenic carcinomas are predominantly found in the upper lobes. However, in nonsmokers, they occur more frequently in the lower lobes. In females, bronchogenic carcinomas present a tendency to occur more often in the lower lobes.

Bevacizumab and non-small-cell lung cancer

Although platinum-based chemotherapy remains a mainstay of non-small-cell lung cancer treatment, its efficacy has probably reached a plateau. Increased understanding of cancer biology has allowed the identification of a number of possible molecular targets, including the EGF receptor and the angiogenesis pathway. ECOG-E4599 has randomised chemonaive patients to receive paclitaxel--carboplatin with and without bevacizumab, a humanised monoclonal antibody targeting the VEGF. The study is the first to show a survival advantage of adding a biological agent to chemotherapy in this setting: in particular, for the first time the survival of lung cancer patients has been extended beyond 1 year. The aim of this review is to describe the biological and clinical properties of bevacizumab and to discuss the evidence that has supported its approval for the first-line treatment of advanced non-squamous non-small-cell lung cancer.

Mortality due to lung cancer in Mexico

The highest mortality due to cancer worldwide for both genders corresponds to lung cancer (1,179,000 deaths). In Mexico, the crude mortality rate due to lung cancer was of 5.01 per 10(5) inhabitants in 1979. The most important risk factor is smoking. The present study was aimed at analyzing the mortality due to lung cancer in Mexico, assessing data from each of the states constituting the Mexican Republic during the 1998-2004 period. Data were obtained from the National Institute of Statistics, Geography and Informatics (INEGI, for its initials in Spanish) corresponding to deaths due to lung cancer (1998-2004). We estimated the mean annual mortality rate (MAMR) for each of the 32 states of Mexico. We used the "World Population Standard". The MAMR was standardized according to age (ARS) direct method, and the standard error was determined by Poisson's approximation at a 95% confidence interval. To know the excess risk due to mortality, we calculated the standardized mortality ratios (SMRs) of ARS for each federal state, using the national rate as reference. In this period, 397,400 deaths due to malignant neoplasms were recorded, corresponding 45,578 (11.5%) to lung cancer; for men, 31,025 (68.1%) with MAMR of 8.9 and the respective ARS of 13.2 both x10(5) inhabitants. For women, results were 4553 (31.9%) deaths with MAMR of 4.1 and ARS of 5.4 both x10(5) inhabitants. The highest mortality rates due to lung cancer in both genders were observed in the north of Mexico, whereas for women this was observed in the central states. Although smoking is the main risk for lung cancer, there are other factors such as environmental pollution or exposure to toxicants that could be associated to this cancer. The years potentially lost due to lung cancer were 258,550 for men and 133,315 for women, with a total of 391,865 according to histopathology registry neoplasm malignant RHNM (1985-1995). Studies focused on the characterization and measurement of polluting agents would be a good start to determine the level of participation of air pollution in the development of lung cancer.

Polimorfismos genéticos: implicações na patogênese do carcinoma medular de tireóide

O carcinoma medular de tireóide (CMT) é uma neoplasia maligna rara, ocorrendo na forma esporádica ou hereditária. Mutações germinativas no proto-oncogene RET são responsáveis pelo CMT hereditário. No entanto, a maioria dos casos de CMT ocorre em indivíduos sem história familiar, na qual a patogênese da doença ainda é pouco compreendida. Os polimorfismos do gene RET são descritos na população geral assim como em pacientes com CMT. Embora estas variações alélicas aparentemente não confiram qualquer atividade transformadora no receptor RET, estudos sugerem que essas alterações genéticas podem modificar a suscetibilidade à doença e o fenótipo clínico em pacientes com CMT esporádico ou hereditário. Uma maior freqüência dos polimorfismos localizados nos exons 11 (G691S), 13 (L769L), 14 (S836S) e 15 (S904) é descrita em pacientes com CMT provenientes de países americanos e europeus. Na presente revisão, analisamos criticamente os resultados obtidos nos diferentes estudos e descrevemos a freqüência dos polimorfismos do RET em pacientes brasileiros com CMT esporádico.