Lung cancer and related risk factors: an update of the literature

Cancer Survivorship and Subjective Cognitive Decline in the United States

PURPOSE

Studies examining the link between cancer survivorship and subjective cognitive decline (SCD) are lacking. Therefore, the current study aimed to determine the association between cancer survivorship and SCD among a nationally representative sample of middle-aged and older adults.

METHOD

Data were obtained from the 2021 Behavioral Risk Factor Surveillance System Survey. Crude and adjusted logistic regression models, controlling for age, gender, race/ethnicity, educational level, income, and work status, were used to determine the association between cancer survivorship characteristics and SCD.

RESULTS

Respondents who were currently undergoing treatment had 86% higher odds of SCD (adjusted odds ratio [aOR] = 1.86; 95% confidence interval [CI] [1.06, 3.27]) compared to respondents who completed treatment. However, those who refused treatment were less likely to report SCD (aOR = 0.006; 95% CI [<0.001, 0.059]) compared to respondents who completed treatment.

CONCLUSION

Cognition interventions may be helpful for individuals diagnosed with cancer who are undergoing treatment, middle-aged, and have not started treatment. [Journal of Gerontological Nursing, 51(4), 12-18.].

A Regional Study to Evaluate the Impact of Coal-fired Power Plants on Lung Cancer Incident Rates

Background

Lung cancer is the leading cause of cancer related deaths. In Kansas, where coal-fired power plants account for 34% of power, we investigated whether hosting counties had higher age-adjusted lung cancer incidence rates. We also examined demographics, poverty levels, percentage of smokers, and environmental conditions using spatial analysis.

Methods

Data from the Kansas Health Matters, and the Behavioral Risk Factor Surveillance System (2010-2014) for 105 counties in Kansas were analyzed. Multiple Linear Regression (MLR) assessed associations between potential risk factors and age-adjusted lung cancer incidence rates while Geographically Weighted Regression (GWR) examined regional risk factors.

Results

Moran's I test confirmed spatial autocorrelation in age-adjusted lung cancer incidence rates (p<0.0003). MLR identified percentage of smokers, population size, and proportion of elderly population as significant predictors of age-adjusted lung cancer incidence rates (p<0.05). GWR showed positive associations between percentage of smokers and age-adjusted lung cancer incidence rates in over 50% of counties.

Conclusion

Contrary to our hypothesis, proximity to a coal-fired power plant was not a significant predictor of age-adjusted lung cancer incidence rates. Instead, percentage of smokers emerged as a consistent global and regional risk factor. Regional lung cancer outcomes in Kansas are influenced by wind patterns and elderly population.

Automated Lung Cancer Segmentation in Tissue Micro Array Analysis Histopathological Images Using a Prototype of Computer-Assisted Diagnosis

Background: Lung cancer is a fatal disease that kills approximately 85% of those diagnosed with it. In recent years, advances in medical imaging have greatly improved the acquisition, storage, and visualization of various pathologies, making it a necessary component in medicine today. Objective: Develop a computer-aided diagnostic system to detect lung cancer early by segmenting tumor and non-tumor tissue on Tissue Micro Array Analysis (TMA) histopathological images. Method: The prototype computer-aided diagnostic system was developed to segment tumor areas, non-tumor areas, and fundus on TMA histopathological images. Results: The system achieved an average accuracy of 83.4% and an F-measurement of 84.4% in segmenting tumor and non-tumor tissue. Conclusion: The computer-aided diagnostic system provides a second diagnostic opinion to specialists, allowing for more precise diagnoses and more appropriate treatments for lung cancer.

The effect of silica exposure on the risk of lung cancer: A dose-response meta-analysis

BACKGROUND

The relationship between silica and the risk of developing lung cancer has been established in previous literature, but how much the level of exposure to silica can increase the risk of lung cancer is a question that has been addressed in this review.

METHODS

Three electronic databases, including MEDLINE, Scopus, and Web of Science were searched for relevant literature. For the dose-response relationship between exposure to silica and developing lung cancer, we performed a meta-analysis using the random-effects model. For each level of exposure, we calculated the overall risk ratio (RR) with 95% confidence intervals (CI).

RESULTS

Nineteen studies were included in the meta-analysis. There was a positive and significant increasing dose-response trend between silica exposure and the risk of developing lung cancer as follows: < 0.50 mg/m³ 1.14 (95% CI: 1.05, 1.23; I² = 79%), 0.50-0.99 mg/m³ 1.34 (95% CI: 1.05, 171; I² = 45%), 1.00-1.99 mg/m³ 1.14 (95% CI: 1.00, 1.30; I² = 70%), 2.00-2.99 mg/m³ 1.47 (95% CI: 1.05, 2.06; I² = 57%), 3.00-3.99 mg/m³ 1.44 (95% CI: 0.99, 2.11; I² = 58%), and ≥ 4.00 mg/m³ 1.64 (95% CI: 1.20, 2.24; I² = 88%). The heterogeneity across studies was mild to moderate.

CONCLUSIONS

The presence of a dose-response relationship favors the causal relationship between exposure to silica and developing lung cancer.

A full-scale experimental study of sub-slab pressure fields induced by underground perforated pipes as a soil depressurisation technique in radon mitigation

Sub-slab depressurisation systems have proven to effectively mitigate radon entry. A poor understanding of the fluid physics underlying the technique has been shown to lower the success rate substantially. This article describes a study of pressure fields in a sub-slab gravel bed induced by a soil depressurisation system consisting of perforated pipes run under the slab at a depth of 75 cm. The advantage of the approach is that pipes can be laid from outside the building to be protected. The study was conducted on a large-scale experimental facility where the variations in morphology and scope of pressure fields with different pipe combinations could be monitored and characterised. The findings showed that pressure was uniform across the entire area in the gravel bed, whereas the sensors buried in natural soil showed pressure to depend on distance from the source. Pressure transfer to the sub-slab plane was also observed to vary depending on the active pipe. Air-flow resistance studies in the layers of soil lying between the pipes and the gravel delivered different results for each pipe. That finding would appear to be related to the presence of preferential pathways in some parts of the soil. Total pressure when several pipes were activated was observed to be practically the same as the sum of the pressures transferred by each when working separately. The correlation between extraction fan power and pressure generated was also analysed. These and other factors are discussed and analysed from a perspective of the understanding of such highly effective techniques.

Diabetic lung disease: fact or fiction?

Diabetes mellitus is a chronic, progressive, incompletely understood metabolic disorder whose prevalence has been increasing steadily worldwide. Even though little attention has been paid to lung disorders in the context of diabetes, its prevalence has recently been challenged by newer studies of disease development. In this review, we summarize and discuss the role of diabetes mellitus involved in the progression of pulmonary diseases, with the main focus on pulmonary fibrosis, which represents a chronic and progressive disease with high mortality and limited therapeutic options.

Geolocation of premises subject to radon risk: Methodological proposal and case study in Madrid

Useful information on the potential radon risk in existing buildings can be obtained by combining data from sources such as potential risk maps, the 'Sistema de Información sobre Ocupación del Suelo de España' (SIOSE) [information system on land occupancy in Spain], cadastral data on built property and population surveys. The present study proposes a method for identifying urban land, premises and individuals potentially subject to radon risk. The procedure draws from geographic information systems (GIS) pooled at the municipal scale and data on buildings possibly affected. The method quantifies the magnitude of the problem in the form of indicators on the buildings, number of premises and gross floor area that may be affected in each risk category. The findings are classified by type of use: residential, educational or office. That information may guide health/prevention policies by targeting areas to be measured based on risk category, or protection policies geared to the construction industry by estimating the number of buildings in need of treatment or remediation. Application of the methodology to Greater Madrid showed that 47% of the municipalities have houses located in high radon risk areas. Using cadastral data to zoom in on those at highest risk yielded information on the floor area of the vulnerable (basement, ground and first storey) premises, which could then be compared to the total. In small towns, the area affected differed only scantly from the total, given the substantial proportion of low-rise buildings in such municipalities.

[Incidence of lung cancer in Jiashan, Zhejiang province: trend analysis from 1987 to 2016 and projection from 2017 to 2019]

OBJECTIVE

To predict the incidence of lung cancer in Jiashan county from 2017 to 2019 on the basis of the incidence rates of lung cancer during 1987-2016.

METHODS

Lung cancer incident cases were derived from cancer registry system of Jiashan. Crude incidence, age-standardized incidence rate by the Chinese standard population (ASR China) and the world standard population (ASR world) were calculated. Annual percent change (APC) was used to examine the temporal trend, and the autoregressive integrated moving average method (ARIMA) of time series model was used to predict the incidence rates from 2017 to 2019.

RESULTS

There were 6103 lung cancer incident cases during 1987-2016 in Jiashan county. Averagely, the crude incidence rate, ASR China and ASR world were 53.77/105, 25.24/105 and 34.15/105, respectively. The crude incidence rate, ASR China and ASR world in male were 78.30/105, 34.77/105 and 51.87/105, which were higher than those in female (29.15/105, 14.31/105 and 17.99/105). Crude incidence rate increased from 27.58/105 in 1987 to 111.24/105 in 2016, and the APC was 5.28%. Crude incidence rate predicted by ARIMA model from 2017 to 2019 would be 135.64/105, 145.97/105 and 152.63/105, and the predicted crude incidence rate for 2017 was close to the real incidence rate in 2017 (135.95/105).

CONCLUSIONS

The incidence of lung cancer in Jiashan has been increased dramatically over the past 30 years and will continue to increase in the future.

Smoking-Related Stigma Expressed by Physiotherapists toward Individuals with Lung Disease

Purpose: We determined the extent and nature of stigma exhibited by a sample of Canadian cardiorespiratory physiotherapists toward people with lung disease who had a smoking history. Method: A quantitative online survey was distributed to Canadian cardiorespiratory physiotherapists, and an anti-smoking attitudes questionnaire was used to measure explicit stigma. We used two case studies with questions to measure implicit stigma. The first involved a patient with chronic obstructive pulmonary disease (COPD) and a smoking history, and the second described a patient with COPD with no smoking history. Results: Of the respondents (n=50), 56% demonstrated mild explicit stigma and 44% demonstrated moderate to severe explicit stigma. The extent of explicit stigma was not associated with respondents' age, area of practice, personal smoking history, or family history of lung disease resulting from smoking. The results indicated no evidence of implicit stigma, and no significant differences were found between the participants' prospective treatments and their professional attitudes toward patient cases. Conclusions: Canadian cardiorespiratory physiotherapists demonstrated explicit stigma toward people with lung disease with a significant smoking history, but there was no evidence of implicit stigma. These findings suggest that further research is needed to investigate how stigma held by cardiorespiratory physiotherapists may affect the quality of care provided for patients with a smoking history.

Genetic variations in cancer-related significantly mutated genes and lung cancer susceptibility

Background

Cancer initiation and development are driven by key mutations in driver genes. Applying high-throughput sequencing technologies and bioinformatic analyses, The Cancer Genome Atlas (TCGA) project has identified panels of somatic mutations that contributed to the etiology of various cancers. However, there are few studies investigating the germline genetic variations in these significantly mutated genes (SMGs) and lung cancer susceptibility.

Patients and methods

We comprehensively evaluated 1655 tagged single nucleotide polymorphisms (SNPs) located in 127 SMGs identified by TCGA, and test their association with lung cancer risk in large-scale case-control study. Functional effect of the validated SNPs, gene mutation frequency and pathways were analyzed.

Results

We found 11 SNPs in 8 genes showed consistent association (P < 0.1) and 8 SNPs significantly associated with lung cancer risk (P < 0.05) in both discovery and validation phases. The most significant association was rs10412613 in PPP2R1A, with the minor G allele associated with a decreased risk of lung cancer [odds ratio = 0.91, 95% confidence interval (CI): 0.87-0.96, P = 2.3 × 10-4]. Cumulative analysis of risk score built as a weight sum of the 11 SNPs showed consistently elevated risk with increasing risk score (P for trend = 9.5 × 10-9). In stratified analyses, the association of PPP2R1A:rs10412613 and lung cancer risk appeared stronger among population of younger age at diagnosis and never smokers. The expression quantitative trait loci analysis indicated that rs10412613, rs10804682, rs635469 and rs6742399 genotypes significantly correlated with the expression of PPP2R1A, ATR, SETBP1 and ERBB4, respectively. From TCGA data, expression of the identified genes was significantly different in lung tumors compared with normal tissues, and the genes' highest mutation frequency was found in lung cancers. Integrative pathway analysis indicated the identified genes were mainly involved in AKT/NF-κB regulatory pathway suggesting the underlying biological processes.

Conclusion

This study revealed novel genetic variants in SMGs associated with lung cancer risk, which might contribute to elucidating the biological network involved in lung cancer development.

Association of Single Nucleotide Polymorphisms in the Apoptosis-Related Genes TP63 and CD40 with Risk for Lung Cancer in a Chinese Han Population

Apoptosis plays a critical role in tumorigenesis. TP63 inhibits the pro-apoptosis function of TP53, and CD40 increases expression of anti-apoptotic proteins. Two single nucleotide polymorphisms (SNPs), rs6790167 (g243059A>G) in intron 9 of TP63 and rs1535045 (g6194C>T) in intron 1 of CD40 respectively, may affect the susceptibility of lung cancer. To evaluate the association of these SNPs with lung cancer, we performed a case-control study with 258 patients, including 149 adenocarcinoma and 47 small cell lung cancer, and 270 controls. Genotyping was conducted using allele-specific polymerase chain reaction and pyrosequencing. We found that rs6790167 and rs1535045 are associated with the risk of lung adenocarcinoma (P = 0.048) and small cell lung cancer (P = 0.019), respectively. Non-smoking males carrying the GG genotype of rs6790167 had higher risk for lung adenocarcinoma than individuals carrying the AA genotype (OR = 7.58, 95% CI: 2.43-23.65). Compared to the TT genotype of rs1535045, non-smoking women with the CC genotype had higher risk for lung adenocarcinoma (OR = 4.20, 95% CI: 1.34-13.12). After stratified analysis based on clinical characteristics, the frequency of the CC genotype of rs1535045 was higher in patients at I-II stages (P = 0.013) or patients whose tumor markers were negative (P = 0.003). Individuals carrying both the GG genotype of rs6790167 and the CC genotype of rs1535045 were associated with significantly higher risk for lung adenocarcinoma. Thus, the polymorphisms in the TP63 and CD40 genes are associated with lung cancer in a Chinese Han population.

Is it feasible to detect epidermal growth factor receptor mutations in circulating tumor cells in nonsmall cell lung cancer?: A meta-analysis

BACKGROUND

The value of circulating tumor cells (CTCs) in detecting epidermal growth factor receptor (EGFR) mutations in patients with nonsmall cell lung cancer (NSCLC) is controversial. We performed a meta-analysis to investigate the diagnostic significance of CTCs with tumor tissues as the standard control.

METHODS

A systematic literature search, including papers published until November 26, 2015, was performed using PubMed, Medline, Embase, Web of Science, and the China National Knowledge Infrastructure, and the references of retrieved articles were screened. The pooled sensitivity, specificity, and diagnostic odds ratio (DOR) were calculated according to the data selection from the included studies. The evaluation indexes of the diagnostic performance were the summary receiver operating characteristic curve (SROC) and area under the SROC (AUSROC).

RESULTS

Eight eligible articles with a total of 170 participants were identified in our meta-analysis. The pooled sensitivity and specificity were 0.91 [95% CI: 0.55-0.99] and 0.99 [95% CI: 0.59-1.00]. The positive likelihood ratio and negative likelihood ratio were 68 [95% CI: 1.4-3364] and 0.09 [95% CI: 0.01-0.64], respectively. The DOR was 788 [95% CI: 9-71884]. The high diagnostic performance of CTCs in detecting EGFR mutations was indicated by the AUSROC of 0.99 [95% CI: 0.98-1.00].

CONCLUSIONS

CTCs are a feasible and highly specific biomarker for detecting the EGFR mutation status in NSCLC patients.

An examination of disparities in cancer incidence in Texas using Bayesian random coefficient models

Disparities in cancer risk exist between ethnic groups in the United States. These disparities often result from differential access to healthcare, differences in socioeconomic status and differential exposure to carcinogens. This study uses cancer incidence data from the population based Texas Cancer Registry to investigate the disparities in digestive and respiratory cancers from 2000 to 2008. A Bayesian hierarchical regression approach is used. All models are fit using the INLA method of Bayesian model estimation. Specifically, a spatially varying coefficient model of the disparity between Hispanic and Non-Hispanic incidence is used. Results suggest that a spatio-temporal heterogeneity model best accounts for the observed Hispanic disparity in cancer risk. Overall, there is a significant disadvantage for the Hispanic population of Texas with respect to both of these cancers, and this disparity varies significantly over space. The greatest disparities between Hispanics and Non-Hispanics in digestive and respiratory cancers occur in eastern Texas, with patterns emerging as early as 2000 and continuing until 2008.

The SNP rs931794 in 15q25.1 Is Associated with Lung Cancer Risk: A Hospital-Based Case-Control Study and Meta-Analysis

Background

Lung cancer is one of the most common human malignant diseases and the leading cause of cancer death worldwide. The rs931794, a SNP located in 15q25.1, has been suggested to be associated with lung cancer risk. Nevertheless, several genetic association studies yielded controversial results.

Methods and Findings

A hospital-based case-control study involving 611 cases and 1062 controls revealed the variant of rs931794 was related to increased lung cancer risk. Stratified analyses revealed the G allele was significantly associated with lung cancer risk among smokers. Following meta-analysis including 6616 cases and 7697 controls confirmed the relevance of rs931794 variant with increased lung cancer risk once again. Heterogeneity should be taken into account when interpreting the consequences. Stratified analysis found ethnicity, histological type and genotyping method were not the sources of between-study heterogeneity. Further sensitivity analysis revealed that the study “Hsiung et al (2010)” might be the major contributor to heterogeneity. Cumulative meta-analysis showed the trend was increasingly obvious with adding studies, confirming the significant association.

Conclusions

Results from our current case-control study and meta-analysis offered insight of association between rs931794 and lung cancer risk, suggesting the variant of rs931794 might be related with increased lung cancer risk.

Anti-diabetic medications do not influence risk of lung cancer in patients with diabetes mellitus: a systematic review and meta-analysis

OBJECTIVES

Several preclinical and observational studies have shown that anti-diabetic medications (ADMs) may modify the risk of lung cancer. We performed a systematic review and meta-analysis evaluating the effect of metformin, sulfonylureas (SUs), thiazolidinediones (TZDs), and insulin on the risk of lung cancer in patients with diabetes mellitus (DM).

MATERIALS AND METHODS

We conducted a systematic search of Pubmed and Web of Science, up to August 20, 2013. We also searched the Conference Proceedings Citation Index (CPCI) and China National Knowledge Infrastructure (CNKI) for abstracts from major meetings. Fixed or random effect pooled measures were selected based on heterogeneity among studies, which was evaluated using Q test and the I2 of Higgins and Thompson. Meta-regression was used to explore the sources of between-study heterogeneity. Publication bias was analyzed by Begg's funnel plot and Egger's regression test. Associations were assessed by odds ratios (ORs) with 95% confidence intervals (CIs).

RESULTS

A total of 15 studies (11 cohort, 4 case-control) were included in this meta-analysis. In observational studies no significant association between metformin (n=11 studies; adjusted OR=0.99, 95%CI: 0.87-1.12), SUs (n=5 studies; adjusted OR=0.98, 95%CI: 0.79-1.22), or TZDs (n=7 studies; adjusted OR=0.92, 95%CI: 0.75-1.13), insulin (n=6 studies; adjusted OR=1.13, 95%CI: 0.79-1.62) use and risk of developing lung cancer was noted. There was considerable inherent heterogeneity between studies not explained by study design, setting, or location.

CONCLUSIONS

Meta-analysis of existing studies does not support a protective or harmful association between ADMs use and risk of lung cancer in patients with DM. There was considerable heterogeneity across studies, and future, well-designed, prospective studies would be required for better understanding of any association.

Metformin decreases lung cancer risk in diabetic patients in a dose-dependent manner

OBJECTIVES

Higher risk of lung cancer has been noted in patients with type 2 diabetes mellitus (DM). Some observational studies have shown a reduced risk of lung cancer in DM patients taking metformin, but a dose-response relationship has never been reported. The aim of this study is to exam the association between the dose of metformin and the incidence of lung cancer in a Chinese population.

MATERIALS AND METHODS

The dataset used for this nationwide population-based study is a cohort of 1 million subjects randomly sampled from individuals enrolled in the Taiwan National Health Insurance system. We enrolled all subjects with newly diagnosed type 2 DM between 1997 and 2007. Subjects with a diagnosis of neoplasm before DM diagnosis, those using metformin before DM diagnosis, those with polycystic ovary syndrome, and those with a DM diagnosis before their 15 years of age were excluded. The demographic data and duration, cumulative dose and intensity of metformin use were compared between patients developing lung cancer and those without lung cancer.

RESULTS

Totally, 47,356 subjects were identified. After adjusting for age, gender, and modified Charlson Comorbidity Index score, the utilization of metformin was an independent protecting factor, and the risk of developing lung cancer decreased progressively with either the higher cumulative dose or the higher intensity of metformin use.

CONCLUSIONS

This study revealed that the use of metformin decreased the risk of lung cancer in a dose-dependent manner in patients with type 2 DM. The chemo-preventive effect of metformin deserves further study.

The assessment of the role of baseline low-dose CT scan in patients at high risk of lung cancer

BACKGROUND

Despite the progress in contemporary medicine comprising diagnostic and therapeutic methods, lung cancer is still one of the biggest health concerns in many countries of the world. The main purpose of the study was to evaluate the detection rate of pulmonary nodules and lung cancer in the initial, helical low-dose CT of the chest as well as the analysis of the relationship between the size and the histopathological character of the detected nodules.

MATERIAL/METHODS

We retrospectively evaluated 1999 initial, consecutive results of the CT examinations performed within the framework of early lung cancer detection program initiated in Szczecin. The project enrolled persons of both sexes, aged 55-65 years, with at least 20 pack-years of cigarette smoking or current smokers. The analysis included assessment of the number of positive results and the evaluation of the detected nodules in relationship to their size. All of the nodules were classified into I of VI groups and subsequently compared with histopathological type of the neoplastic and nonneoplastic pulmonary lesions.

RESULTS

Pulmonary nodules were detected in 921 (46%) subjects. What is more, malignant lesions as well as lung cancer were significantly, more frequently discovered in the group of asymptomatic nodules of the largest dimension exceeding 15 mm.

CONCLUSIONS

The initial, low-dose helical CT of the lungs performed in high risk individuals enables detection of appreciable number of indeterminate pulmonary nodules. In most of the asymptomatic patients with histopathologically proven pulmonary nodules greater than 15 mm, the mentioned lesions are malignant, what warrants further, intensified diagnostics.

Comparative assessment of selected metals in the scalp hair and nails of lung cancer patients and controls

Lung cancer is seriously threatening human health and exposure to trace metals is the most important aetiology for lung cancer. Selected essential/toxic metals (Ca, Mg, Na, K, Fe, Zn, Cu, Sr, Li, Co, Mn, Ni, Cr, Cd and Pb) are measured in the scalp hair and nails of lung cancer patients and controls by atomic absorption spectrophotometric method employing nitric acid-perchloric acid-based wet digestion. Average concentrations of Pb, Cd, Mn, Co and Cu are found to be significantly higher (p < 0.05) in the scalp hair and nails of lung cancer patients compared with the controls, however, appreciably higher concentrations of Zn, Ca, Na, Mg and Cr are noted in the scalp hair of the controls. Most of the metal levels reveal higher dispersion and asymmetry in the scalp hair/nails of the patients compared with the controls. Average metal levels are also compared to investigate probable differences based on sex, abode, food and smoking habits. The correlation study shows significantly diverse mutual variations of the metals in the scalp hair and nails of the patients and controls. Considerable variations in the metal levels are also noted for various stages and types of lung cancer (adenocarcinoma, squamous cell carcinoma, large cell carcinoma and small cell lung cancer). Multivariate apportionment of the metals in the scalp hair and nails of the patients and controls are also significantly diverse. The study reveals considerably divergent variations in the metal levels in lung cancer patients in comparison with healthy subjects.

A functional polymorphism in the promoter of ERK5 gene interacts with tobacco smoking to increase the risk of lung cancer in Chinese populations

Mitogen/extracellular signal-regulated kinase-5 (MEK5)/extracellular signal-regulated protein kinase-5 (ERK5) pathway plays a pro-oncogenic role in tumourigenesis by anticell apoptosis, promoting cell proliferation and differentiation in response to extracellular stimuli. As overexpressed MEK5/ERK5 is involved in the development of lung cancer, we hypothesised that the single nucleotide polymorphisms (SNPs) in MEK5 and ERK5 genes may influence gene expression and thus be associated with lung cancer risk. Five putative functional polymorphisms (rs3743353T>C, rs7172582C>T and rs2278076A>G of MEK5 and rs3866958G>T and rs2233083C>T of ERK5) were genotyped in two independent case-control studies with a total of 1559 lung cancer patients and 1679 controls in southern and eastern Chinese population. We found the rs3866958G>T of ERK5 was significantly associated with lung cancer risk, while other SNPs were not. Compared with the rs3866958TG/TT genotypes, the GG genotype conferred an increased risk of lung cancer (odds ratio = 1.30, 95% confidence interval = 1.12-1.51, P = 5.0×10(-4)), and this effect was more pronounced in smokers, accompanying with a significant interaction with smoking (P interaction = 0.013). The GG genotype also had significant higher mRNA levels of ERK5 in lung cancer tissues than TG/TT genotypes (P = 1.0×10(-4)); the luciferase reporter with the G allele showed significant higher transcription activities than the T allele, especially after the treatment with tobacco extract in vitro. Our data indicated that the functional polymorphism rs3866958G>T in ERK5 was associated with an increased lung cancer risk in smokers by virtue of the positive interaction with smoking on promoting the ERK5 expression, which might be a valuable indicator for predicting lung cancer risk in smokers.

Diabetes mellitus as an independent risk factor for lung cancer: a meta-analysis of observational studies

BACKGROUND

Epidemiologic studies have demonstrated inconsistent associations between diabetes mellitus and the risk of lung cancer. To determine whether diabetes mellitus is associated with an increased risk of lung cancer, we performed a meta-analysis of observational studies.

METHODS

PubMed, EMBASE and the Cochrane Library were searched for observational studies conducted prior to September 2012. We included prospective cohort studies that reported relative risks and case-control studies that showed odds ratios in the analysis. The pooled relative risk (RR) with 95% confidence intervals (CIs) was calculated with a random effects model. Sensitivity analysis was performed with studies which controlled for smoking status. Associations were assessed in several subgroups representing different participant and study characteristics.

RESULTS

A total of 34 studies from 24 manuscripts (10 case-control studies and 24 cohort studies) were included in the analyses. Diabetes was significantly associated with the increased risk of lung cancer compared with non-diabetic controls when limiting the analysis to studies adjusting for smoking status (RR, 1.11; 95% CI, 1.02-1.20; I(2)=46.1%). By contrast, this association disappeared when the analysis was restricted to studies not adjusting for smoking status (RR, 0.99; 95% CI, 0.88-1.11; I(2)=96.7%). When stratifying by sex, an increased risk of lung cancer was prominent in diabetic women (RR, 1.14; 95% CI, 1.09-1.20; I(2)=0%), while there was no association in diabetic men (RR, 1.07; 95% CI, 0.89-1.28; I(2)=96.6%). Among diabetic women, significantly increased risks of lung cancer were found in the following subgroups: cohort studies (RR, 1.14; 95% CI, 1.08-1.20; I(2)=0%), studies controlling for major confounding variables such as age, smoking and alcohol (RR, 1.19; 95% CI, 1.00-1.43; I(2)=23.1%), studies with long-term follow-up (RR, 1.14; 95% CI, 1.08-1.20; I(2)=0%), and high-quality studies assessed by the Newcastle-Ottawa Scale (RR, 1.14; 95% CI, 1.08-1.20; I(2)=0%).

INTERPRETATION

Preexisting diabetes mellitus may increase the risk of lung cancer, especially among female diabetic patients. Further large-scale prospective studies are needed to test specifically the effect of diabetes mellitus on lung cancer risk.

Antidiabetes drugs correlate with decreased risk of lung cancer: a population-based observation in Taiwan

BACKGROUND

The risk of some forms of cancer has been found to be higher in patients with diabetes mellitus (DM) than in the general population. The aim of this study was to examine, with sufficient statistical power, the association between DM and lung cancer and the impact of antidiabetes drugs on lung cancer risk in Taiwan.

MATERIALS AND METHODS

From a randomly selected data set of 1 million National Health Insurance (NHI) claims in Taiwan from 2000-2005, 19,624 cases (patients ≥ 20 years of age) of newly diagnosed DM were identified. From the same data set, 78,496 enrollees with no record of DM were selected as controls and were matched in sex and age to the first group. The incidence of newly diagnosed lung cancer was compared between patients with DM and controls for a period of 9 years (2000-2008).

RESULTS

The multivariate Cox model analysis showed a slightly increased hazard ratio (HR) of 1.05 of lung cancer in patients with DM, but the association was not statistically significant. However the use of antidiabetes drugs, such as metformin, thiazolidinediones, or alpha-glucosidase inhibitors, correlates with a decreased lung cancer risk of 39%-45%. A significant association was found between lung cancer risk and male sex (HR, 2.23), pulmonary tuberculosis (HR, 1.60), chronic obstructive pulmonary disease (HR, 1.21), and age (HR, 1.07).

CONCLUSION

Patients with DM are not at increased risk for the development of lung cancer, but the use of antidiabetes drugs would considerably decrease the risk. In this cohort, male sex, age, pulmonary tuberculosis, and chronic obstructive pulmonary disease were all associated with an increased risk of lung cancer, consistent with findings in the literature and indicative of the validity of our study.

Variations in HSPA1B at 6p21.3 are associated with lung cancer risk and prognosis in Chinese populations

The heat shock protein Hsp70 is crucial for regulating cellular homeostasis in stressed cells. Although the tumorigenic potential and prognostic applications of Hsp70 have been widely investigated, it remains unclear whether genetic variations of the human isoforms HSPA1L, HSPA1A, and HSPA1B are associated with cancer risk and prognosis. In this study, we genotyped six tagSNPs in these genes in 1,152 paired patients with lung cancer and controls, and then validated the results in additional cohorts of 1,781 patients with lung cancer and 1,038 controls. In addition, we evaluated the associations of these tagSNPs with survival in 330 patients with advanced non-small cell lung cancer (NSCLC) with additional validation in another 331 patients with advanced NSCLC. Functions of the risk variants identified were investigated using cell-based reporter assays. We found that the HSPA1B rs6457452T allele was associated with increased lung cancer risk compared with the rs6457452C allele in both data sets and also pooled analysis (adjusted OR = 1.41; P = 2.8 × 10(-5)). The HSPA1B rs2763979TT genotype conferred poor survival outcomes for patients with advanced NSCLC in two independent cohorts and pooled analysis [adjusted hazard ratio (HR) = 1.80, 1.61, and 1.66; P = 0.013, 0.036, and 0.002, respectively]. Lastly, we also found that the rs2763979T and rs6457452T alleles were each sufficient to reduce expression of transcriptional reporter constructs, when compared with the rs2763979C and rs6457452C alleles, respectively. Taken together, our findings define that functional HSPA1B variants are associated with lung cancer risk and survival. These Hsp70 genetic variants may offer useful biomarkers to predict lung cancer risk and prognosis.

Smoking Cessation Practices of Dental Care Providers in Eastern Province of Saudi Arabia

Background:Awareness programs are highly recommended to educate smokers and help them to quit. The aim of this study is to evaluate dental professionals' awareness and utilisation of the 5As in the Eastern Province of Saudi Arabia. Material andMethods:A survey was conducted in Saudi Arabia on 102 dental care providers (DCPs) in 2010 to assess awareness of 5As. Many factors were included in the survey such as demographic characteristics, working place, years of experiences, level of education and country of graduation.Results:Only 23 (22.5%) of our sample know about the 5As (Ask, Advise, Assess, Assist and Arrange), and less than 7% of DCPs assist their patients to quit smoking. In addition, 19 (18.6%) of DCPs were smokers, and of them 6 (31.6%) smoked in front of their patients.Conclusion:Most of the dental practitioners were not aware of the 5As for smoking cessation. Most of them they did not pay attention to the willingness of their patients to quit smoking.

Consumption of fruit and vegetables and risk of lung cancer: a case-control study in Galicia, Spain

OBJECTIVE

We analyzed the effect of fruit and vegetable intake on lung cancer risk in a population in northwest Spain.

METHODS

We analyzed data from a hospital-based case-control study including 295 histologically confirmed cases and 322 controls. Controls were patients attending the hospital for minor surgery. There was a minimum age limit of 35 y and sampling was carried out on a sex-frequency basis.

RESULTS

After adjustment for sex, age, tobacco use, and occupation, no protective effect of overall consumption of fruit was present (odds ratio 1.49, 95% confidence interval 0.81-2.73). Green leafy vegetables conferred a protective effect (odds ratio 0.50, 95% confidence interval 0.30-0.83).

CONCLUSION

These findings indicate that green leafy vegetables, rather than fruit, might have a genuine protective effect against lung cancer.

From cell signaling to cancer therapy

Cancer has been seriously threatening the health and life of humans for a long period. Despite the intensive effort put into revealing the underlying mechanisms of cancer, the detailled machinery of carcinogenesis is still far from fully understood. Numerous studies have illustrated that cell signaling is extensively involved in tumor initiation, promotion and progression. Therefore, targeting the key molecules in the oncogenic signaling pathway might be one of the most promising ways to conquer cancer. Some targeted drugs, such as imatinib mesylate (Gleevec), herceptin, gefitinib (Iressa), sorafenib (Nexavar) and sunitinib (Sutent), which evolve from monotarget drug into multitarget ones, have been developed with encouraging effects.

Nucleotide excision repair as a marker for susceptibility to tobacco-related cancers: a review of molecular epidemiological studies

DNA repair is a complicated biological process consisting of several distinct pathways that play a central role in maintaining genomic stability. Research on DNA repair and cancer risk is a vital, emerging field that recently has seen rapid advances facilitated by the completion of the Human Genome Project. In this review, we described phenotypic and genotypic markers of nucleotide excision repair (NER) that have been used in molecular epidemiology studies. We summarized the population-based studies to date that have examined the association between DNA repair capacity phenotype and genetic polymorphisms of the NER genes and risk of tobacco-related cancers, including cancers of the lung, head and neck, prostate, bladder, breast, and esophagus. We also included studies of melanoma and nonmelanoma skin cancers because individuals with defective NER, such as patients with xeroderma pigmentosum (XP) are highly susceptible to ultraviolet light (UV)-induced melanoma and nonmelanoma skin cancers. The published data provide emerging evidence that DNA repair capacity may contribute to genetic susceptibility to cancers in the general population. However, many of the studies are limited in terms of the size of the study populations. Furthermore, all published findings are still considered preliminary, the assays used in the studies have yet to be validated, and the results need to be confirmed. Large and well-designed population-based studies are warranted to assess gene-gene and gene-environment interactions and to ultimately determine, which biomarkers of DNA repair capacity are useful for screening high-risk populations for primary prevention and early detection of tobacco-related cancers.