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There is unmet need to develop circulating biomarkers that would enable earlier interception of lung cancer when more effective treatment options are available. Here, a set of 30 miRNAs, selected from a review of the published literature were assessed for their predictive performance in identifying lung cancer cases in the pre-diagnostic setting. The 30 miRNAs were assayed using sera collected from 102 individuals diagnosed with lung cancer within one year following blood draw and 212 controls matched for age, sex, and smoking status. The additive performance of top-performing miRNA candidates in combination with a previously validated four-protein marker panel (4MP) consisting of the precursor form of surfactant protein B (Pro-SFTPB), cancer antigen 125 (CA125), carcinoembryonic antigen (CEA) and cytokeratin-19 fragment (CYFRA21-1) was additionally assessed. Of the 30 miRNAs evaluated, five (miR-320a-3p, miR-210-3p, miR-92a-3p, miR-21-5p, and miR-140-3p) were statistically significantly (Wilcoxon rank sum test p < 0.05) elevated in case sera compared to controls, with individual AUCs ranging from 0.57–0.62. Compared to the 4MP alone, the combination of 3-miRNAs + 4MP improved sensitivity at 95% specificity by 19.1% ((95% CI of difference 0.0–28.6); two-sided p: 0.006). Our findings demonstrate utility for miRNAs for early detection of lung cancer in combination with a four-protein marker panel.

Purpose The neutrophil-to-lymphocyte ratio (NLR) is a marker of systemic inflammation that has been reported to be associated with survival after chronic disease diagnoses, including lung cancer. We hypothesized that the inflammatory profile reflected by pre-diagnosis NLR, rather than the well-studied pre-treatment NLR at diagnosis, may be associated with increased mortality after lung cancer is diagnosed in high-risk heavy smokers. Methods We examined associations between pre-diagnosis methylation-derived NLR (mdNLR) and lung cancer-specific and all-cause mortality in 279 non-small lung cancer (NSCLC) and 81 small cell lung cancer (SCLC) cases from the β-Carotene and Retinol Efficacy Trial (CARET). Cox proportional hazards models were adjusted for age, sex, smoking status, pack years, and time between blood draw and diagnosis, and stratified by stage of disease. Models were run separately by histotype. Results Among SCLC cases, those with pre-diagnosis mdNLR in the highest quartile had 2.5-fold increased mortality compared to those in the lowest quartile. For each unit increase in pre-diagnosis mdNLR, we observed 22–23% increased mortality (SCLC-specific hazard ratio [HR] = 1.23, 95% confidence interval [CI]: 1.02, 1.48; all-cause HR = 1.22, 95% CI 1.01, 1.46). SCLC associations were strongest for current smokers at blood draw (Interaction Ps = 0.03). Increasing mdNLR was not associated with mortality among NSCLC overall, nor within adenocarcinoma (N = 148) or squamous cell carcinoma (N = 115) case groups. Conclusion Our findings suggest that increased mdNLR, representing a systemic inflammatory profile on average 4.5 years before a SCLC diagnosis, may be associated with mortality in heavy smokers who go on to develop SCLC but not NSCLC.

Pre-diagnosis circulating leukocyte profiles, including higher white blood cell (WBC) counts and neutrophil-to-lymphocyte ratios (NLR), have been reported to be associated with non-small cell lung cancer (NSCLC) risk. Higher neutrophil levels were recently reported to drive NSCLC-WBC count associations, implicating the innate immune response in NSCLC risk and etiology. Though not directly measurable in bio-banked blood, leukocyte subtype proportions can be estimated using established deconvolution algorithms applied to genome-wide DNA methylation data. We previously reported that NSCLC risk was elevated in heavy smokers with greater pre-diagnosis methylation-derived NLR (mdNLR). Here, we examine the influence of each pre-diagnosis mdNLR leukocyte subtype (neutrophils, and lymphocytes: B, Natural Killer, CD8+T, and CD4+T cells), separately on NSCLC risk. In our nested case-control study from the Beta Carotene and Retinol Efficacy Trial of heavy smokers (≥20 pack years), 243 NSCLC cases were 1:1 matched to controls on age (±5 years), sex, race and ethnicity, enrollment (±2 years), smoking status (ever/never), asbestos exposure, and follow-up time. Methylation was assayed on the Illumina EPIC array in whole blood collected on average 4.4 years (range 0.1-10.1) before diagnosis in NSCLC cases. We assessed conditional logistic regression models for each mdNLR-related leukocyte subtype, dichotomized at the median in controls, and further adjusted for continuous age and smoking pack years at blood draw. We evaluated NSCLC risk overall, and in subgroup strata: histotype, sex, smoking status, asbestos exposure, stage at diagnosis, age at blood draw, age at diagnosis, and time between blood draw and diagnosis. A greater than median level of neutrophils was suggestively associated with NSCLC risk (OR=1.40, 95% CI: 0.93-2.12); this association was restricted to squamous cell carcinoma (SCC n=103 pairs; 2.00, 1.03-3.86), with no association for adenocarcinoma (n=132 pairs; 0.99, 0.57-1.73). SCC-neutrophil associations were strongest among former smokers (n=26 pairs; 6.81, 1.48-31.3), cases with ≤ 4.4 years between blood draw and diagnosis (n=48 pairs; 3.00, 1.10-8.14), cases aged > 64.8 years at blood draw (n=56 pairs; 2.66, 1.05-6.73), and cases diagnosed at stage III or IV (n=61 pairs; 2.21, 0.92-5.30). Greater than median lymphocyte levels were suggestively associated with reduced NSCLC (0.71, 0.47-1.08) and SCC risk (0.62, 0.32-1.21), but less so for adenocarcinoma (0.85, 0.48-1.50). Though statistically imprecise, SCC-lymphocyte associations were strongest for CD4+T cells (0.56, 0.28-1.12). Our results indicate that greater pre-diagnosis neutrophil levels may be a biomarker for SCC, but not adenocarcinoma, in heavy smokers. Given the descriptive nature of this analysis, small sample size, and multiple testing, additional research is needed to replicate these findings. Citation Format: Laurie Grieshober, Stefan Graw, Matt J. Barnett, Gary E. Goodman, Chu Chen, Devin C. Koestler, Carmen J. Marsit, Jennifer A. Doherty. Pre-diagnostic methylation-based leukocyte profiles and non-small cell lung cancer risk in heavy smokers [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3005.

INTRODUCTION: The relationship between Body-Mass-Index (BMI) and lung cancer prognosis is heterogeneous. We evaluated the impact of sex, smoking and race on the relationship between BMI and overall survival (OS) in non-small-cell-lung-cancer (NSCLC). METHODS: Data from 16 individual ILCCO studies were pooled to assess interactions between BMI and the following factors on OS: self-reported race, smoking status and sex, using Cox models (adjusted hazard ratios; aHR) with interaction terms and adjusted penalized smoothing spline plots in stratified analyses. RESULTS: Among 20,937 NSCLC patients with BMI values, females = 47 %; never-smokers = 14 %; White-patients = 76 %. BMI showed differential survival according to race whereby compared to normal-BMI patients, being underweight was associated with poor survival among white patients (OS, aHR = 1.66) but not among black patients (aHR = 1.06; p(interaction) = 0.02). Comparing overweight/obese to normal weight patients, Black NSCLC patients who were overweight/obese also had relatively better OS (p(interaction) = 0.06) when compared to White-patients. BMI was least associated with survival in Asian-patients and never-smokers. The outcomes of female ever-smokers at the extremes of BMI were associated with worse outcomes in both the underweight (p(interaction)

Background A low level of methylation at cg05575921 in the aryl-hydrocarbon receptor repressor (AHRR) gene is robustly associated with smoking, and some studies have observed associations between cg05575921 methylation and increased lung cancer risk and mortality. To prospectively examine whether decreased methylation at cg05575921 may identify high risk subpopulations for lung cancer screening among heavy smokers, and mortality in cases, we evaluated associations between cg05575921 methylation and lung cancer risk and mortality, by histotype, in heavy smokers. Methods The β-Carotene and Retinol Efficacy Trial (CARET) included enrollees ages 45–69 with ≥ 20 pack-year smoking histories and/or occupational asbestos exposure. A subset of CARET participants had cg05575921 methylation available from HumanMethylationEPIC assays of blood collected on average 4.3 years prior to lung cancer diagnosis in cases. Cg05575921 methylation β-values were treated continuously for a 10% methylation decrease and as quintiles, where quintile 1 (Q1, referent) represents high methylation and Q5, low methylation. We used conditional logistic regression models to examine lung cancer risk overall and by histotype in a nested case-control study including 316 lung cancer cases (diagnosed through 2005) and 316 lung cancer-free controls matched on age (±5 years), sex, race/ethnicity, enrollment year, current/former smoking, asbestos exposure, and follow-up time. Mortality analyses included 372 lung cancer cases diagnosed between 1985 and 2013 with available methylation data. We used Cox proportional hazards models to examine mortality overall and by histotype. Results Decreased cg05575921 methylation was strongly associated with smoking, even in our population of heavy smokers. We did not observe associations between decreased pre-diagnosis cg05575921 methylation and increased lung cancer risk, overall or by histotype. We observed linear increasing trends for lung cancer-specific mortality across decreasing cg05575921 methylation quintiles for adenocarcinoma and small cell carcinoma (P-trends = 0.01 and 0.04, respectively). Conclusions In our study of heavy smokers, decreased cg05575921 methylation was strongly associated with smoking but not increased lung cancer risk. The observed association between cg05575921 methylation and increased mortality in adenocarcinoma and small cell histotypes requires further examination. Our results do not support using decreased cg05575921 methylation as a biomarker for lung cancer screening risk stratification.

Background Telomeres protect cells from genomic instability. We examined telomere length and lung cancer risk prospectively in heavy smokers. Methods In a nested case–control study with 709 cases and 1313 controls, conditional logistic regression was used to evaluate associations between telomere length (global, chromosome 5p, and 13q) and lung cancer risk by histotype, controlling for detailed smoking history. Results Risks of overall lung cancer and adenocarcinoma were suggestively elevated among individuals with telomere length in the longest tertile. No clear patterns were observed for other histotypes, or for chromosome 5p or 13q telomere length. Associations with adenocarcinoma were strongest among (OR, 95% CI for longest versus shortest tertile): former smokers (2.26, 1.03–4.96), individuals

IntroductionThe relationships between morbid obesity, changes in body mass index (BMI) before cancer diagnosis, and lung cancer outcomes by histology (SCLC and NSCLC) have not been well studied.MethodsIndividual level data analysis was performed on 25,430 patients with NSCLC and 2787 patients with SCLC from 16 studies of the International Lung Cancer Consortium evaluating the association between various BMI variables and lung cancer overall survival, reported as adjusted hazard ratios (aHRs) from Cox proportional hazards models and adjusted penalized smoothing spline plots.ResultsOverall survival of NSCLC had putative U-shaped hazard ratio relationships with BMI based on spline plots: being underweight (BMI < 18.5 kg/m2; aHR= 1.56; 95% confidence interval [CI]:1.43-1.70) or morbidly overweight (BMI > 40 kg/m2; aHR= 1.09; 95% CI: 0.95-1.26) at the time of diagnosis was associated with worse stage-specific prognosis, whereas being overweight (25 kg/m2 ≤ BMI < 30 kg/m2; aHR= 0.89; 95% CI: 0.85-0.95) or obese (30 kg/m2 ≤ BMI ≤ 40 kg/m2; aHR= 0.86; 95% CI: 0.82-0.91) was associated with improved survival. Although not significant, a similar pattern was seen with SCLC. Compared with an increased or stable BMI from the period between young adulthood until date of diagnosis, a decreased BMI was associated with worse outcomes in NSCLC (aHR= 1.24; 95% CI: 1.2-1.3) and SCLC patients (aHR=1.26 (95% CI: 1.0-1.6). Decreased BMI was consistently associated with worse outcome, across clinicodemographic subsets.ConclusionsBoth being underweight or morbidly obese at time of diagnosis is associated with lower stage-specific survival in independent assessments of NSCLC and SCLC patients. In addition, a decrease in BMI at lung cancer diagnosis relative to early adulthood is a consistent marker of poor survival.

Epigenetic alterations, including changes in DNA methylation, and telomere length (TL) are established molecular markers of aging, morbidity, and mortality. We hypothesized that older methylation-derived biologic age (meAge) measured prior to lung cancer diagnoses would be associated with increased post-diagnosis mortality in high risk heavy smokers. Our study included 372 lung cancer cases from the β-Carotene and Retinol Efficacy Trial (CARET), a unique population of heavy smokers at high risk for lung cancer. Genome-wide DNA methylation data (Illumina MethylationEPIC) and TL were assayed in blood collected on average 4.9 years prior to diagnosis. We estimated meAge using scores developed by Hannum (leukocytes; 65/71 CpGs), Horvath (pan tissue; 335/353 CpGs), and Levine (DNAm PhenoAge, whole blood; 513 CpGs). We assessed Pearson correlations between meAge, age at blood draw, and log2-transformed TL, and we defined meAge acceleration (ΔmeAge) as the difference between each meAge and age. We examined associations between ΔmeAge, with and without TL adjustment, and all-cause mortality after lung cancer diagnoses using Cox proportional hazards models adjusted for age, sex, smoking status, pack years, time between blood draw and diagnosis, and methylation-estimated blood cell counts, including a strata variable for early (I/II), late (III/IV), or unknown stage. We assessed mortality in those with both old meAge and short TL (dichotomized at the medians) compared to those with both young meAge and long TL. We modeled all cases and by histotype (adenocarcinoma N=148, squamous cell N=115, small cell N=81). In our study population, mean age (64.3) was underestimated by Hannum and Levine meAges (52.4 and 57.0, respectively) and overestimated by Horvath meAge (70.3). Age was positively correlated with meAges (Hannum r=0.55, P=1E-30; Horvath r=0.49, P=2E-24; Levine r=0.41, P=2E-16), as were meAges with each other (all r≥0.66, P≤3E-48). TL was negatively correlated with age (r=-0.13, P=0.01) and meAges (Hannum r=-0.20, P=0.0001; Horvath r=-0.17, P=0.001; Levine r=-0.15, P=0.003). While each year of age was associated with 3% higher mortality in all cases (95% confidence interval (CI): 1.01-1.06), we did not observe an independent association with ΔmeAge (Hannum 0.99, 0.97-1.01; Horvath 1.00, 0.99-1.02; Levine 1.00, 0.99-1.01) regardless of TL adjustment or histotype. Shorter TL was associated with increased mortality in those who developed small cell lung cancer, as we reported previously; here, we observed that this association was independent of ΔmeAge. Combined old meAge and short TL was not associated with mortality. Though prospectively collected ΔmeAge has been reported to predict all-cause mortality in population-based studies, we did not observe that pre-diagnosis ΔmeAge, nor combined meAge-TL, were associated with mortality in a group of heavy smokers who went on to develop lung cancer. Citation Format: Laurie Grieshober, Stefan Graw, Matt J. Barnett, Mark D. Thornquist, Gary E. Goodman, Chu Chen, Devin C. Koestler, Carmen J. Marsit, Jennifer A. Doherty. Methylation-derived biologic age, telomere length, and lung cancer mortality in heavy smokers from CARET [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 774.

Hypomethylation of cg05575921 in the aryl-hydrocarbon receptor repressor (AHRR) gene is consistently and strongly associated with higher exposure to smoking (e.g., current smoking, greater number of pack years, and less time since quitting). Although cg05575921 hypomethylation has been reported to be associated with lung cancer risk and mortality, this has not been explored within heavy smokers or by histotype. We assessed cg05575921 methylation for associations with smoking behavior, prospective lung cancer risk, and mortality in 313 cases and controls from the Beta Carotene and Retinol Efficacy Trial (CARET) with ≥20 pack years of smoking and matched on age (±5 years), sex, race/ethnicity, enrollment year, smoking status, occupational asbestos exposure, and follow-up time. Methylation of cg05575921 in blood collected on average 4.3 years prior to diagnosis in cases was assayed using the 850K Illumina EPIC array. Quintiles of cg05575921 methylation were defined based on the control distribution, with the lowest quintile (Q1, referent) representing hypermethylation and the highest (Q5), hypomethylation. Among controls, increasing quintiles of cg05575921 hypomethylation were associated with current smoking status (Cochran-Armitage trend p=3.0 × 10-21), and with decreasing years since last smoked, increasing cigarettes per day, and decreasing body mass index (BMI) (ordinal ANOVA p=3.1 × 10-21, 1.3 × 10-17, and 0.002, respectively). We observed similar patterns in cases. We evaluated associations between cg05575921 methylation and lung cancer risk using logistic regression models conditioned on matching factors and adjusted for age, years since quit, and BMI. We evaluated cg05575921 methylation and lung cancer-specific mortality using Cox proportional hazards models adjusted for stage, age, sex, race, smoking status, intervention arm, asbestos exposure, and pack years smoked. We did not observe clear patterns of associations between cg05575921 methylation and lung cancer risk overall or by histotype. However, we found a linear relationship (p=0.03) between increasing cg05575921 hypomethylation and overall lung cancer mortality, with Q5 vs Q1 Hazard Ratio (HR)=1.60 (95% Confidence Interval (95% CI): 1.00-2.57) for mortality from lung cancer overall, and HR=2.09, 95% CI: 0.96-4.54 for adenocarcinoma (N=121). Our findings provide preliminary support that even among heavy smokers, cg05575921 hypomethylation is associated with more recent and extensive exposure to cigarette smoking, and that prediagnosis cg05575921 hypomethylation in lung cancer cases is associated with an increased hazard of death. However, since the CARET population represents a group who would largely qualify for lung cancer screening with annual low-dose computed tomography per the United States Preventive Task Force guidelines, our results do not provide support for the use of cg05575921 hypomethylation as an indicator for screening-based lung cancer risk stratification. Citation Format: Stefan Graw, Matt J. Barnett, Mark D. Thornquist, Gary E. Goodman, Chu Chen, Devin C. Koestler, Carmen J. Marsit, Jennifer A. Doherty, Laurie Grieshober. AHRR hypomethylation in heavy smokers: Associations with lung cancer risk and mortality [abstract]. In: Proceedings of the AACR Special Conference on Modernizing Population Sciences in the Digital Age; 2019 Feb 19-22; San Diego, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(9 Suppl):Abstract nr A20.

Epigenome-wide association studies (EWAS) have been used to identify variation in methylation of cytosine-phosphate-guanine (CpG) sites associated with many phenotypes, including lung cancer. A recent meta-EWAS revealed that associations between CpG methylation and lung cancer risk differ by smoking status. Also, smoking status, intensity, and time since cessation are associated with changes in peripheral blood DNA methylation across the genome. We sought to address whether genome-wide methylation differences are associated with lung cancer risk in 316 matched lung cancer case and control pairs from the Beta Carotene and Retinol Efficacy Trial (CARET) of heavy smokers (≥20 pack years). Case-control pairs were matched on age (±5 years), sex, race/ethnicity, enrollment year (±2 years), smoking status (ever/never), occupational asbestos exposure (yes/no), and follow-up time. Genome-wide DNA methylation was assayed on the Illumina EPIC array in whole blood samples collected on average 4.1 years prior to diagnosis in cases. To improve scalability for testing, we mapped 866,326 normalized and processed EPIC array CpGs to 26,994 gene regions using the EPIC array annotation. We performed region-based variance component tests for associations between each region and lung cancer risk. We modeled associations as random effects such that changes reflecting both hyper- and hypo-methylation across different CpG sites in a gene region cumulatively contribute to the overall variance component test. The test assesses whether the variance associated with the regression coefficient for each CpG in the region is equal to zero. Since this method does not have a conditional adaptation for matched study designs, our region-based models included adjustment for age, sex, race/ethnicity, enrollment year, smoking status, and occupational asbestos exposure, as well as pack years and the first two principal components estimated from the genome-wide methylation data. Our preliminary results include 66 genes (12 in adenocarcinoma, 33 in squamous, 21 in small cell) with permutation-based P Citation Format: Laurie Grieshober, Jincheng Shen, Stefan Graw, Matt J. Barnett, Mark D. Thornquist, Gary E. Goodman, Chu Chen, Devin C. Koestler, Carmen J. Marsit, Jennifer A. Doherty. Leveraging genome-wide methylation data to understand lung cancer risk in heavy smokers [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 1205.

The development of cancer is driven by the accumulation of many oncogenesis-related genetic alterations and tumorigenesis is triggered by complex networks of involved genes rather than independent actions. To explore the epistasis existing among oncogenesis-related genes in lung cancer development, we conducted pairwise genetic interaction analyses among 35,031 SNPs from 2027 oncogenesis-related genes. The genotypes from three independent genome-wide association studies including a total of 24,037 lung cancer patients and 20,401 healthy controls with Caucasian ancestry were analyzed in the study. Using a two-stage study design including discovery and replication studies, and stringent Bonferroni correction for multiple statistical analysis, we identified significant genetic interactions between SNPs in RGL1:RAD51B (OR=0.44, p value=3.27x10-11 in overall lung cancer and OR=0.41, p value=9.71x10-11 in non-small cell lung cancer), SYNE1:RNF43 (OR=0.73, p value=1.01x10-12 in adenocarcinoma) and FHIT:TSPAN8 (OR=1.82, p value=7.62x10-11 in squamous cell carcinoma) in our analysis. None of these genes have been identified from previous main effect association studies in lung cancer. Further eQTL gene expression analysis in lung tissues provided information supporting the functional role of the identified epistasis in lung tumorigenesis. Gene set enrichment analysis revealed potential pathways and gene networks underlying molecular mechanisms in overall lung cancer as well as histology subtypes development. Our results provide evidence that genetic interactions between oncogenesis-related genes play an important role in lung tumorigenesis and epistasis analysis, combined with functional annotation, provides a valuable tool for uncovering functional novel susceptibility genes that contribute to lung cancer development by interacting with other modifier genes.

The aim of this study was to investigate the association between BMI (kg/m) and prostate cancer risk. BMI is a modifiable lifestyle factor and may provide a unique opportunity for primary prevention of prostate cancer if a causal association exists. Data from 11 886 men from the Carotene and Retinol Efficacy Trial (CARET, 1985-1996 with active follow-up through 2005) comprising current and former heavy smokers were analyzed. CARET was a multicenter randomized, double-blind placebo-controlled chemoprevention trial testing daily supplementation of 30 mg β-carotene+25 000 IU retinyl palmitate for primary prevention of lung cancer. Prostate cancer was a secondary outcome. Nonaggressive disease was defined as Gleason less than 7 and stage I/II. Aggressive disease was primarily defined as at least Gleason 7 or stage III/IV, and secondarily by excluding Gleason 3+4 from the first definition. BMI was calculated from measured weight and height. Cox proportional hazards regression models were used to estimate hazard ratios (HRs) with 95% confidence intervals (CIs) for cancer incidence between BMI categories. During follow-up, 883 men were diagnosed with prostate cancer. In the analysis of aggressive disease when Gleason 3+4 was excluded, men with a BMI of at least 35 kg/m had an increased rate of prostate cancer (HR: 1.80, 95% CI: 1.04-3.11, Ptrend=0.04) compared with men with BMI 18-24.9 kg/m. No other differences were seen in risk estimates for overall, nonaggressive or aggressive prostate cancer including all Gleason 7 cases, between BMI categories. Our results show an association between having a BMI of at least 35 kg/m and an increased risk of aggressive prostate cancer (not including Gleason 3+4 tumors), but do not support an association between BMI and risk of overall, aggressive disease including all Gleason 7, or nonaggressive prostate cancer within a population of current and former heavy smokers.

Background Obesity has been proposed as a potential protective factor against lung cancer. We examined the association between BMI and lung cancer risk in a pooled analysis based on nested case-control studies from four cohort studies. Methods A case-control study was nested within four cohorts in USA, Europe, China and Singapore that included 4172 cases and 8471 control subjects. BMI at baseline was calculated as weight in kilograms divided by height in meters squared (kg/m2), and classified into 4 categories: underweight (BMI

Purpose We have investigated the potential of metabolomics to discover blood-based biomarkers relevant to lung cancer screening and early detection. An untargeted metabolomics approach was applied to identify biomarker candidates using prediagnostic sera from the Beta-Carotene and Retinol Efficacy Trial (CARET) study. Patients and Methods A liquid chromatography/mass spectrometry hydrophilic interaction method designed to profile a wide range of metabolites was applied to prediagnostic serum samples from CARET participants (current or former heavy smokers), consisting of 100 patients who subsequently developed non–small-cell lung cancer (NSCLC) and 199 matched controls. A separate aliquot was used to quantify levels of pro-surfactant protein B (pro-SFTPB), a previously established protein biomarker for NSCLC. On the basis of the results from the discovery set, blinded validation of a metabolite, identified as N1,N12-diacetylspermine (DAS), and pro-SFTPB was performed using an independent set of CARET prediagnostic sera from 108 patients with NSCLC and 216 matched controls. Results Serum DAS was elevated by 1.9-fold, demonstrating significant specificity and sensitivity in the discovery set for samples collected up to 6 months before diagnosis of NSCLC. In addition, DAS significantly complemented performance of pro-SFTPB in both the discovery and validations sets, with a combined area under the curve in the validation set of 0.808 (P < .001 v pro-SFTPB). Conclusion DAS is a novel serum metabolite with significant performance in prediagnostic NSCLC and has additive performance with pro-SFTPB.

Introduction Chronic inflammation has been implicated in carcinogenesis, with increasing evidence of its role in lung cancer. We aimed to evaluate the role of genetic polymorphisms in inflammation-related genes in the risk for development of lung cancer. Methods A nested case-control study design was used, and 625 cases and 625 well-matched controls were selected from participants in the β-Carotene and Retinol Efficacy Trial, which is a large, prospective lung cancer chemoprevention trial. The association between lung cancer incidence and survival and 23 polymorphisms descriptive of 11 inflammation-related genes (interferon gamma gene [ IFNG ], interleukin 10 gene [ IL10 ], interleukin 1 alpha gene [ IL1A ], interleukin 1 beta gene [ IL1B ], interleukin 2 gene [ IL2 ], interleukin 4 receptor gene [ IL4R ], interleukin 4 gene [ IL4 ], interleukin 6 gene [ IL6 ], prostaglandin-endoperoxide synthase 2 gene [ PTGS2 ] (also known as COX2 ), transforming growth factor beta 1 gene [ TGFB1 ], and tumor necrosis factor alpha gene [ TNFA ]) was evaluated. Results Of the 23 polymorphisms, two were associated with risk for lung cancer. Compared with individuals with the wild-type (CC) variant, individuals carrying the minor allele variants of the IL-1β-511 C>T promoter polymorphism (rs16944) (CT and TT) had decreased odds of lung cancer (OR = 0.74, [95% confidence interval (CI): 0.58–0.94] and OR = 0.71 [95% CI: 0.50–1.01], respectively, p = 0.03). Similar results were observed for the IL-1β-1464 C>G promoter polymorphism (rs1143623), with presence of the minor variants CG and CC having decreased odds of lung cancer (OR = 0.75 [95% CI: 0.59–0.95] and OR = 0.69 [95% CI: 0.46–1.03], respectively, p = 0.03). Survival was not influenced by genotype. Conclusions This study provides further evidence that IL1B promoter polymorphisms may modulate the risk for development of lung cancer.

Non-small cell lung cancer is the most common type of lung cancer. Both environmental and genetic risk factors contribute to lung carcinogenesis. We conducted a genome-wide interaction analysis between single nucleotide polymorphisms (SNPs) and smoking status (never-versus ever-smokers) in a European-descent population. We adopted a two-step analysis strategy in the discovery stage: we first conducted a case-only interaction analysis to assess the relationship between SNPs and smoking behavior using 13 336 non-small cell lung cancer cases. Candidate SNPs with P-value

Data are very limited on vitamin D and lung cancer prevention in high-risk populations. The authors investigated whether estimated vitamin D intake was associated with lung cancer risk and whether effect modification by vitamin A existed among current/former heavy smokers and workers with occupational exposure to asbestos. A case-cohort study selected 749 incident lung cancers and 679 noncases from the Carotene and Retinol Efficacy Trial (CARET), 1988-2005. The active intervention was supplementation of 30 mg β-carotene + 25,000 IU retinyl palmitate/day. Baseline total intake including both diet (from food frequency questionnaire) and personal supplements (from brand names linked to the labeled potencies) was assessed. Hazard ratios (HRs) were estimated by Cox proportional hazard models. No significant association of total vitamin D intake with lung cancer was observed overall. However, total vitamin D intake ≥600 versus

The neutrophil-to-lymphocyte ratio (NLR) is a marker of systemic inflammation that has been reported to be associated with smoking status as well as survival outcomes from chronic diseases including lung cancer. Most prior studies have examined NLR measured in blood collected at diagnosis, which may therefore reflect disease-related inflammation. Although blood cell type counts, and therefore NLR, cannot be quantified in stored samples, algorithms have been developed to estimate blood cell type counts based on lineage-specific DNA methylation patterns across the genome as methylation-derived NLR (mdNLR). We hypothesize that the inflammatory profile reflected by pre-diagnosis mdNLR may be associated with lung cancer mortality. To test this hypothesis, we examined mdNLR and lung cancer-specific mortality, overall and by histotype, among 293 cases from the Beta Carotene and Retinol Efficacy Trial (CARET) of heavy smokers (≥20 pack years). We used the ratio of predicted neutrophil and lymphocyte proportions derived from DNA methylation signatures in whole blood samples collected on average 4.1 years prior to diagnosis, to estimate mdNLR, which was discretized as quartiles ranging from lowest to highest; i.e. low to high levels of systemic inflammation. We fit Cox proportional hazards models adjusted for age, sex, race (white vs non-white), smoking status, intervention arm, asbestos exposure, and pack years smoked to examine the association between mdNLR lung cancer-specific mortality. We also adjusted for time between blood draw and diagnosis and included early versus late stage as a stratification variable. mdNLR was not associated with mortality for all cases combined, nor squamous cell carcinoma (N=100) or small cell lung cancer (N=59). In contrast, for adenocarcinoma (N=122), we observed a statistically significant linear trend (p=0.02) for increasing quartiles of mdNLR and adenocarcinoma-specific mortality, with a hazard ratio (HR) of 2.03 (95% Confidence Interval (CI): 1.03-4.03) comparing the highest (Q4) to lowest (Q1) mdNLR quartiles. Though subgroup analyses were sparse, we observed associations of larger magnitude (Q4 compared to Q1) for those who were younger at blood draw (HR=4.70, 95% CI: 1.73-12.76) and at diagnosis (HR=6.09, 95% CI: 1.98-18.72), as well as those with smoking histories lower than the median of 53 pack years (HR=2.91, 95% CI: 1.03-8.22) and those in the active intervention arm (HR=3.32, 95% CI: 1.11-9.93). Our findings suggest that an inflammatory response prior to diagnosis as indicated by higher mdNLR levels may be associated with mortality in heavy smokers who go on to develop lung adenocarcinoma. Since indicators of survival may be used to guide treatment decisions and gauge response to treatment, further research into the association between mdNLR and lung adenocarcinoma-specific survival is needed to understand its potential clinical utility. Citation Format: Laurie Grieshober, Stefan Graw, Matt J. Barnett, Mark D. Thornquist, Gary E. Goodman, Chu Chen, Devin Koestler, Carmen Marsit, Jennifer Doherty. Pre-diagnosis neutrophil-to-lymphocyte ratio and lung cancer mortality [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 3300.

Purpose Preliminary studies have identified pro–surfactant protein B (pro-SFTPB) to be a promising blood biomarker for non–small-cell lung cancer. We conducted a study to determine the independent predictive potential of pro-SFTPB in identifying individuals who are subsequently diagnosed with lung cancer. Patients and Methods Pro-SFTPB levels were measured in 2,485 individuals, who enrolled onto the Pan-Canadian Early Detection of Lung Cancer Study by using plasma sample collected at the baseline visit. Multivariable logistic regression models were used to evaluate the predictive ability of pro-SFTPB in addition to known lung cancer risk factors. Calibration and discrimination were evaluated, the latter by an area under the receiver operating characteristic curve (AUC). External validation was performed with samples collected in the Carotene and Retinol Efficacy Trial (CARET) participants using a case-control study design. Results Adjusted for age, sex, body mass index, personal history of cancer, family history of lung cancer, forced expiratory volume in one second percent predicted, average number of cigarettes smoked per day, and smoking duration, pro-SFTPB (log transformed) had an odds ratio of 2.220 (95% CI, 1.727 to 2.853; P < .001). The AUCs of the full model with and without pro-SFTPB were 0.741 (95% CI, 0.696 to 0.783) and 0.669 (95% CI, 0.620 to 0.717; difference in AUC P < .001). In the CARET Study, the use of pro-SFPTB yielded an AUC of 0.683 (95% CI, 0.604 to 0.761). Conclusion Pro-SFTPB in plasma is an independent predictor of lung cancer and may be a valuable addition to existing lung cancer risk prediction models.

We investigated associations of serum α- and γ-tocopherols and their effect modification by polymorphisms in oxidative stress regulatory enzymes in relation to prostate cancer risk. In a nested case-control study in the Carotene and Retinol Efficacy Trial, prerandomized serum α- and γ-tocopherol were assayed among 684 men with incident prostate cancer [375 nonaggressive and 284 aggressive cancer (stage III/IV or Gleason score ≥7)] and 1441 controls. Manganese superoxide dismutase Ala-16Val (rs4880), glutathione peroxidase 1 Pro200Leu (rs1050450), catalase −262 C > T (rs1001179), and myeloperoxidase (MPO) G–463A (rs2333227) were genotyped. A multivariate-adjusted inverse association of serum α-tocopherol with total prostate cancer risk was observed in current smokers (OR = 0.62, 95% CI = 0.40–0.96, 4th vs. 1st quartiles). High (≥median) compared to low serum concentrations of α- and γ-tocopherol were inversely associated with aggressive prostate cancer in current smokers (OR = 0.50, 95% CI = 0.32–0.78 and OR = 0.64, 95% CI = 0.43–0.95, respectively). The association was stronger among those with MPO G/A+A/A genotypes. Among current smokers with low serum α-tocopherol concentrations, MPO G/A+A/A, the genotypes downregulating oxidative stress, were associated with an increased risk for aggressive prostate cancer (OR = 2.06, 95% CI = 1.22–3.46). Conversely, current smokers with these genotypes who had high α-tocopherol concentrations had a reduced risk for aggressive prostate cancer (OR = 0.34, 95% CI = 0.15–0.80; P-interaction = 0.001). In conclusion, among current smokers, both high serum α- and γ-tocopherol concentrations were associated with reduced risks of aggressive prostate cancer. The α-tocopherol–associated risks are modified by polymorphism in MPO G–463A.

The neutrophil-to-lymphocyte ratio (NLR) is a marker of systemic inflammation that is inversely associated with survival for many chronic diseases, including lung cancer. We hypothesize that the inflammatory profile reflected by DNA methylation-derived NLR (mdNLR) may also be associated with lung cancer risk. We assessed the relationship between pre-diagnosis mdNLR and lung cancer risk in a nested case-control study of the β-Carotene and Retinol Efficacy Trial (CARET), a population at high risk for lung cancer due to heavy smoking (≥20 pack years; current smoker or quit ≤6 years before enrollment) or substantial occupational asbestos exposure (current smoker or quit ≤15 years before enrollment). We matched 319 incident lung cancer cases to controls based on time at risk, age at blood draw, smoking status, sex, race, asbestos exposure, and enrollment year. We computed mdNLR using the ratio of predicted neutrophil and lymphocyte proportions derived from DNA methylation signatures in whole blood samples collected prior to diagnosis (mean 4.31 years in cases). Conditional logistic regression models were adjusted for potential confounding factors: age, pack years of smoking, cigarettes per day, and body mass index. Mean mdNLR was higher in cases at 2.06 than in controls at 1.86 (p=0.04). Each unit increase in mdNLR was associated with a 21% increased risk of lung cancer (Odds Ratio (OR) 1.21, 95% Confidence Interval (CI) 1.01-1.45). There was a 30% increased risk of non-small cell lung cancer (NSCLC; n=240 pairs; 1.30, 1.03-1.63); estimates for adenocarcinoma and squamous cell NSCLC were similar. mdNLR was not associated with small cell lung cancer (n=68 pairs; 1.06, 0.77-1.47). The association between mdNLR and NSCLC risk was most pronounced in those with asbestos exposure (3.39, 1.32-8.67; all men). Estimates for NSCLC cases without asbestos exposure were similar for men (1.15, 0.88-1.51) and women (1.22, 0.75-1.98). We assessed whether mdNLR and NSCLC risk associations varied by tertiles of time at risk among cases: 0-2.7 years, 2.8-5.4 years, and 5.5-9.8 years. Though NSCLC risk was suggestively elevated in each time period stratum, the magnitude of the association was largest for the time period closest to diagnosis (1.49, 0.92-2.41; 1.26, 0.86-1.84; and 1.30, 0.88-1.91, respectively). This is the first study to evaluate whether pre-diagnosis mdNLR is associated with lung cancer risk, and we assessed this association in a sample of heavy smokers. Our findings suggest that the inflammatory response produced by both smoking and asbestos may be reflected by mdNLR. A better understanding of the role of mdNLR in NSCLC etiology may improve detection of nascent lung cancer, thereby improving treatment strategies in NSCLC patients. Citation Format: Laurie Grieshober, Stefan Graw, Matt J. Barnett, Mark D. Thornquist, Gary E. Goodman, Chu Chen, Devin C. Koestler, Carmen J. Marsit, Jennifer A. Doherty. Pre-diagnosis neutrophil-to-lymphocyte ratio and lung cancer risk in heavy smokers [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 3235.

CA125, human epididymis protein 4 (HE4), mesothelin, B7-H4, decoy receptor 3 (DcR3), and spondin-2 have been identified as potential ovarian cancer biomarkers. Except for CA125, their behavior in the prediagnostic period has not been evaluated.Immunoassays were used to determine concentrations of CA125, HE4, mesothelin, B7-H4, DcR3, and spondin-2 proteins in prediagnostic serum specimens (1-11 samples per participant) that were contributed 0-18 years before ovarian cancer diagnosis from 34 patients with ovarian cancer (15 with advanced-stage serous carcinoma) and during a comparable time interval before the reference date from 70 matched control subjects who were participating in the Carotene and Retinol Efficacy Trial. Lowess curves were fit to biomarker levels in cancer patients and control subjects separately to summarize mean levels over time. Receiver operating characteristic curves were plotted, and area-under-the curve (AUC) statistics were computed to summarize the discrimination ability of these biomarkers by time before diagnosis.Smoothed mean concentrations of CA125, HE4, and mesothelin (but not of B7-H4, DcR3, and spondin-2) began to increase (visually) in cancer patients relative to control subjects approximately 3 years before diagnosis but reached detectable elevations only within the final year before diagnosis. In descriptive receiver operating characteristic analyses, the discriminatory power of these biomarkers was limited (AUC statistics range = 0.56-0.75) but showed increasing accuracy with time approaching diagnosis (eg, AUC statistics for CA125 were 0.57, 0.68, and 0.74 foror = 4, 2-4, and2 years before diagnosis, respectively).Serum concentrations of CA125, HE4, and mesothelin may provide evidence of ovarian cancer 3 years before clinical diagnosis, but the likely lead time associated with these markers appears to be less than 1 year.

We investigated dietary supplement use and prostate cancer risk in the Carotene and Retinol Efficacy Trial (CARET). CARET was a randomized, double-blinded, placebo-controlled trial testing a daily dose of 30 mg β-carotene + 25,000 IU retinyl palmitate for lung cancer prevention (1985-1996; active follow-up occurred through 2005). Secondary outcomes, including prostate cancer, were also assessed. Participants were queried about dietary supplements, health history, family history of cancer, smoking, and lifestyle habits. Cox proportional hazards regression estimated multivariate-adjusted relative risk [and 95% confidence intervals (95% CI)] of prostate cancer for dietary supplement users and nonusers with or without the high-dose CARET vitamins during the intervention and postintervention phases. After an average of 11 years of follow-up, 890 prostate cancer cases were reported. Neither the CARET nor other supplements were associated with total prostate cancer risk. For aggressive prostate cancer, men in the CARET intervention arm who used additional supplements had a relative risk for aggressive prostate cancer (Gleason ≥7 or stage III/IV) of 1.52 (95% CI, 1.03-2.24; P < 0.05), relative to all others. These associations disappeared in the postintervention period (0.75; 95% CI, 0.51-1.09). Conversely, there was no association of CARET + other supplements with nonaggressive disease, relative to all others. There was no effect modification by smoking or time on CARET intervention in any analyses. CARET only included smokers, so findings reported here may not apply to nonsmokers. Our results are consistent with other studies suggesting that dietary supplements may influence prostate cancer risk.(Cancer Epidemiol Biomarkers Prev 2009;18(8):2202–6)

Objectives: The Pro12Ala variant in the peroxisome proliferator-activated receptor γ (PPARG) gene has been associated with diabetes and several cancers. This pilot study tested for the association between Pro12Ala and pancreatic cancer risk in a high-risk sample of smokers. Methods: A nested case-control study was conducted in 83 incident cases of pancreatic cancer and 166 matched controls originally recruited into a cohort chemoprevention study of lung cancer. Associations between Pro12Ala and pancreatic cancer risk were measured using conditional logistic regression. Results: Carriers of the G allele (Ala) of the Pro12Ala variant had a borderline increased relative risk of pancreatic cancer compared with homozygous carriers of the C allele (Pro), with an odds ratio of 1.79 (95% confidence interval [CI], 0.96-3.33; P = 0.06). Among subjects randomized to high-dose vitamin A, the odds ratio was 2.80 (95% CI, 1.16-6.74; P = 0.02) versus 1.20 (95% CI, 0.45-3.23; P = 0.71) in the placebo group. A haplotype including Pro12Ala was also significantly associated with pancreatic cancer risk in all subjects and in subjects randomized to vitamin A. Conclusions: This analysis presents the first evidence that PPARG may be associated with pancreatic cancer risk, and this candidate gene should be investigated in future, larger studies.

To examine the association between breast cancer risk and the fatty acid composition of phospholipids in prediagnostic serum samples.We analyzed the fatty acid composition in 130 incident postmenopausal breast cancer cases and 257 matched controls nested within the beta-Carotene and Retinol Efficacy Trial Cohort. The fatty acid composition was measured by gas chromatography. Multivariate-adjusted odds ratios and corresponding 95% confidence intervals for the risk of breast cancer were estimated using logistic regression. Stratified analysis was conducted by smoking status.There were no associations with breast cancer risk for total saturated, monounsaturated, n-3, n-6, or trans fatty acids among all women. For individual fatty acids, we observed an inverse association with the trans linoleic acid, 18:2n6tt (p(trend)=0.0002). Among current smokers, long-chain saturated fatty acids (22:0 and 24:0) and total 16:1 trans fatty acids were positively associated with the risk of breast cancer, whereas these fatty acids showed no association among former smokers.Overall, we observed no significant association between serum phospholipid fatty acids and breast cancer risk, except for the trans linoleic acid isomer 18:2n6tt, which was unexpected. Our finding of a positive association of long-chain saturated fatty acids (22:0 and 24:0) and total 16:1 trans fatty acids with the risk of breast cancer only in current smokers may suggest an effect modification by smoking status. Our findings need to be replicated in future epidemiologic studies.

PurposeWe have implemented a high throughput platform for quantitative analysis of serum autoantibodies, which we have applied to lung cancer for discovery of novel antigens and for validation in prediagnostic sera of autoantibodies to antigens previously defined based on analysis of sera collected at the time of diagnosis.Materials and MethodsProteins from human lung adenocarcinoma cell line A549 lysates were subjected to extensive fractionation. The resulting 1,824 fractions were spotted in duplicate on nitrocellulose-coated slides. The microarrays produced were used in a blinded validation study to determine whether annexin I, PGP9.5, and 14-3-3 theta antigens previously found to be targets of autoantibodies in newly diagnosed patients with lung cancer are associated with autoantibodies in sera collected at the presymptomatic stage and to determine whether additional antigens may be identified in prediagnostic sera. Individual sera collected from 85 patients within 1 year before a diagnosis of lung cancer and 85 matched controls from the Carotene and Retinol Efficacy Trial (CARET) cohort were hybridized to individual microarrays.ResultsWe present evidence for the occurrence in lung cancer sera of autoantibodies to annexin I, 14-3-3 theta, and a novel lung cancer antigen, LAMR1, which precede onset of symptoms and diagnosis.ConclusionOur findings suggest potential utility of an approach to diagnosis of lung cancer before onset of symptoms that includes screening for autoantibodies to defined antigens.

Iron overload may increase prostate cancer risk through stimulation of oxidative stress, and endogenous pro- and antioxidant capabilities, i.e. manganese superoxide dismutase (MnSOD) and myeloperoxidase (MPO), may modify these associations. We investigated this hypothesis in the Carotene and Retinol Efficacy Trial cohort in a nested case–control study. Although there was no association between iron intake and risk overall, there was a suggestion of increased risk of clinically aggressive prostate cancer with higher iron intake [odds ratio (OR) = 1.4, 95% confidence interval (CI) = 0.9–2.0]. Associations were most notable for men with aggressive prostate cancer who were below the median consumption of total fruits and vegetables (OR = 1.8, 95% CI = 1.1–3.2). Associations between MPO −463 G to A genotype (rs2333227) and prostate cancer risk were only noted among men with aggressive cancer, with more than a 2-fold risk reduction among men with AA genotypes (OR = 0.4, 95% CI = 0.2–1.0); MnSOD was not associated with risk overall, but the MnSOD T to C (Val-9Ala, rs4880) polymorphism modified associations between risk of clinically aggressive prostate cancer and dietary iron intake (P for interaction = 0.02). Among aggressive cancer cases with the TT genotype, higher iron intake level was associated with >2-fold increase in risk (OR = 2.3, 95% CI = 1.0–4.9), whereas there was no association among men with CC genotypes (OR = 0.9, 95% CI = 0.4–2.3). Although interactions were not significant, there were similar patterns for MPO genotype, iron intake and risk. These findings suggest that higher iron intake may be associated with risk of clinically aggressive prostate cancer, and that endogenous antioxidant capabilities may modify these associations.

Previous studies have suggested occurrence of altered serum glycan profiles in patients with lung cancer. Here, we aimed to determine the predictive value of serum glycans to distinguish non–small cell lung cancer (NSCLC) cases from controls in prediagnostic samples using a previously validated predictive protein marker pro-SFTPB, as anchor. Blinded prediagnostic serum samples were obtained from the Carotene and Retinol Efficacy Trial (CARET), and included a discovery set of 100 NSCLC cases and 199 healthy controls. A second test set consisted of 108 cases and 216 controls. Cases and controls were matched for age at baseline (5-year groups), sex, smoking status (current vs. former), study enrollment cohort, and date of blood draw. Serum glycan profiles were determined by mass spectrometry. Twelve glycan variables were identified to have significant discriminatory power between cases and controls in the discovery set (AUC > 0.6). Of these, four were confirmed in the independent validation set. A combination marker yielded AUCs of 0.74 and 0.64 in the discovery and test set, respectively. Four glycan variables exhibited significant incremental value when combined with pro-SFTPB compared with pro-SFTPB alone with AUCs of 0.73, 0.72, 0.72, and 0.72 in the test set, indicating that serum glycan signatures have relevance to risk assessment for NSCLC. Cancer Prev Res; 9(4); 317–23. ©2016 AACR.

BACKGROUND: Some observational studies suggest that a higher selenium status is associated with a lower risk of prostate cancer but have been generally too small to provide precise estimates of associations, particularly by disease stage and grade. METHODS: Collaborating investigators from 15 prospective studies provided individual-participant records (from predominantly men of white European ancestry) on blood or toenail selenium concentrations and prostate cancer risk. Odds ratios of prostate cancer by selenium concentration were estimated using multivariable-adjusted conditional logistic regression. All statistical tests were two-sided. RESULTS: Blood selenium was not associated with the risk of total prostate cancer (multivariable-adjusted odds ratio [OR] per 80 percentile increase = 1.01, 95% confidence interval [CI] = 0.83 to 1.23, based on 4527 case patients and 6021 control subjects). However, there was heterogeneity by disease aggressiveness (ie, advanced stage and/or prostate cancer death, Pheterogeneity = .01), with high blood selenium associated with a lower risk of aggressive disease (OR = 0.43, 95% CI = 0.21 to 0.87) but not with nonaggressive disease. Nail selenium was inversely associated with total prostate cancer (OR = 0.29, 95% CI = 0.22 to 0.40, Ptrend < .001, based on 1970 case patients and 2086 control subjects), including both nonaggressive (OR = 0.33, 95% CI = 0.22 to 0.50) and aggressive disease (OR = 0.18, 95% CI = 0.11 to 0.31, Pheterogeneity = .08). CONCLUSIONS: Nail, but not blood, selenium concentration is inversely associated with risk of total prostate cancer, possibly because nails are a more reliable marker of long-term selenium exposure. Both blood and nail selenium concentrations are associated with a reduced risk of aggressive disease, which warrants further investigation.

We have implemented a strategy to identify tumor antigens that induce a humoral immune response in lung cancer based on the analysis of tumor cell proteins. Chromatographically fractionated protein extracts from three lung cancer cell lines were subjected to Western blotting and hybridization with individual sera to determine serum antibody binding. Two sets of sera were initially investigated. One set consisted of sera from 19 newly diagnosed subjects with lung adenocarcinoma and 19 matched controls. A second independent set consisted of sera from 26 newly diagnosed subjects with lung adenocarcinoma and 24 controls matched for age, gender, and smoking history. One protein that exhibited significant reactivity with both sets of cancer sera (P = 0.0008) was confidently identified by mass spectrometry as 14-3-3𝛉. Remarkably, significant autoantibody reactivity against 14-3-3𝛉 was also observed in an analysis of a third set consisting of 18 prediagnostic lung cancer sera collected as part of the Beta-Carotene and Retinol Efficacy Trial cohort study, relative to 19 matched controls (P = 0.0042). A receiver operating characteristic curve constructed with a panel of three proteins consisting of 14-3-3𝛉 identified in this study, plus annexin 1 and protein gene product 9.5 proteins previously identified as associated with autoantibodies in lung cancer, gave a sensitivity of 55% at 95% specificity (area under the curve, 0.838) in discriminating lung cancer at the preclinical stage from matched controls. [Cancer Res 2007;67(24):12000–6]

We assessed whether spirometric measurements are associated with the development of accelerated FEV(1) decline and lung cancer among active and previous smokers with a wide range of lung function. Bivariate and multivariate analyses that adjusted for age, intervention arm, smoking status at enrollment and smoking history, years exposed to asbestos, and evidence of asbestosis were used to assess whether baseline FEV(1) and FEV(1)/FVC ratio were associated with accelerated FEV(1) decline and incident lung cancer. The 3,041 participants enrolled from 1985 to 1994 were followed through April 30, 2005. Baseline FEV(1)/FVC ratio0.7 was significantly associated with an increased risk for rapid lung function decline (OR=1.73; 95% CI 1.31-2.28; p0.001). Baseline FEV(1)/FVC ratio0.7 was also significantly associated with an increased risk of developing lung cancer, even when baseline FEV(1) was80%. Lung cancer risk among participants with baseline airflow obstruction and FEV(1)60% was 4-fold higher than participants without baseline airflow obstruction and FEV(1)80% (p0.001), even among former smokers. These data indicate an FEV(1)/FVC0.7 among smokers is significantly associated with faster airflow loss, and an increased risk for developing lung cancer, even among those individuals with a normal FEV(1).

To test whether infection with select human polyomaviruses (HPyV) and human papillomaviruses (HPV) is associated with incident lung cancer. We performed a nested case–control study, testing serum from the carotene and retinol efficacy trial, conducted 1985–2005, for antibodies to Merkel cell (MCV), KI (KIV), and WU (WUV) HPyVs as well as to six high-risk and two low-risk HPV types. Incident lung cancer cases (n = 200) were frequency-matched with controls (n = 200) on age, enrollment and blood draw dates, intervention arm assignment, and the number of serum freeze/thaw cycles. Sera were tested using multiplex liquid bead microarray antibody assays. We used logistic regression to assess the association between HPyV and HPV antibodies and lung cancer. There was no evidence of a positive association between levels of MCV, KIV, or WUV antibodies and incident lung cancer (p corrected >0.10 for all trend tests; odds ratio (OR) range 0.72–1.09, p corrected >0.10 for all). There was also no evidence for a positive association between HPV 16 or 18 infection and incident lung cancer (p corrected ≥0.10 for all trend tests; OR range 0.25–2.54, p > 0.05 for all OR > 1), but the number of persons with serologic evidence of these infections was small. Prior infection with any of several types of HPyV or HPV was not associated with subsequent diagnosis of lung cancer. Infection with these viruses likely does not influence a person’s risk of lung cancer in Western smoking populations.

Despite numerous published studies, debate continues regarding the risk of developing lung cancer among men exposed occupationally to asbestos, particularly those without radiographic or functional evidence of asbestosis. The beta-Carotene and Retinol Efficacy Trial (CARET), a study of vitamin supplementation for chemoprevention of lung cancer, has followed 4,060 heavily exposed US men for 9-17 years. Lung cancer incidence for 1989-2002 was analyzed using a stratified proportional hazards model. The study confirmed excessive rates of lung cancer among men with radiographic asbestosis. Comparison of study arms revealed a strong, unanticipated synergy between radiographic profusion category and the active intervention. In the large subgroup of men with normal lung parenchyma on chest radiograph at baseline, there was evidence of exposure-related lung cancer risk: Men with more than 40 years' exposure in high-risk trades had a risk approximately fivefold higher than men with 5-10 years, after adjustment for covariates. The effect in these men was independent of study intervention arm, but pleural plaques on the baseline radiograph and abnormal baseline flow rate were strong independent predictors of subsequent lung cancer. Residual confounding by subclinical asbestosis, exposure to unmeasured lung carcinogens, or differences in smoking are unlikely to explain these observations better than a carcinogenic effect of asbestos per se.

In the prostate, the enzyme encoded by the SRD5A2 gene (5α-reductase) converts testosterone to dihydrotestosterone, a potent androgen that has been hypothesized to play a role in the genesis of prostate cancer. Several polymorphisms have been identified in the SRD5A2 gene, including a valine-to-leucine substitution (V89L) at codon 89, a variable number of TA dinucleotide repeats and a missense substitution at codon 49 resulting in an amino acid substitution of alanine with threonine (A49T). To investigate the influence of these polymorphisms on prostate cancer risk, we conducted a case-control study nested within the Beta-Carotene and Retinol Efficacy Trial. Genotypes were determined by PCR-based capillary electrophoresis using genomic DNA isolated from 300 cases and 300 controls matched on the basis of race, age at enrollment (within 5 years), enrollment study center and year of randomization. There was no association between V89L genotypes and prostate cancer risk. The age- and race-adjusted odds ratio (OR) associated with the VL and LL genotypes were 1.06 (95% confidence interval (CI) = 0.75-1.49) and 0.99 (95% CI = 0.57-1.73), respectively, as compared to the VV genotype. The age- and race-adjusted odds ratio for men having 1 TA(9) or TA(18) allele was 0.98 (95% CI = 0.64-1.48) when compared to men without TA repeats. The corresponding odds ratio for men without the TA(0) alleles was 0.68 (95% CI = 0.21-2.19). The age- and race-adjusted odds ratio associated with having at least 1 T allele at codon 49 was 1.11 (95% CI = 0.58-2.11), as compared to the AA genotype. Our results do not support the hypothesis that the V89L and A49T polymorphisms in the SRD5A2 gene are related to the risk of prostate cancer, but are compatible with the suggestion from earlier studies that men who are homozygous for the TA(9) or (18) alleles and men who have the TA(9)/TA(18) genotype are at a modestly reduced risk. © 2003 Wiley-Liss, Inc.

Although there is no proven benefit associated with screening for lung cancer, screening programs are attracting many individuals who perceive themselves to be at high risk due to smoking. We sought to determine whether the risk of lung cancer varies predictably among smokers.We used data on 18 172 subjects enrolled in the Carotene and Retinol Efficacy Trial (CARET)-a large, randomized trial of lung cancer prevention-to derive a lung cancer risk prediction model. Model inputs included the subject's age, sex, asbestos exposure history, and smoking history. We assessed the model's calibration by comparing predicted and observed rates of lung cancer across risk deciles and validated it by assessing the extent to which a model estimated on data from five CARET study sites could predict events in the sixth study site. We then applied the model to evaluate the risk of lung cancer among smokers enrolled in a study of lung cancer screening with computed tomography (CT).The model was internally valid and well calibrated. Ten-year lung cancer risk varied greatly among participants in the CT study, from 15% for a 68-year-old man who has smoked two packs per day for 50 years and continues to smoke, to 0.8% for a 51-year-old woman who smoked one pack per day for 28 years before quitting 9 years earlier. Even among the subset of CT study participants who would be eligible for a clinical trial of cancer prevention, risk varied greatly.The risk of lung cancer varies widely among smokers. Accurate risk prediction may help individuals who are contemplating voluntary screening to balance the potential benefits and risks. Risk prediction may also be useful for researchers designing clinical trials of lung cancer prevention.

The Carotene and Retinol Efficacy Trial (CARET) was a large, multicenter randomized chemoprevention trial designed to test a combined lung cancer prevention agent in heavy smokers and workers exposed to asbestos. In January 1996, the CARET Steering Committee decided to stop the intervention due to an adverse effect. This paper describes the decision process used to apply the stopping rules and the activities engaged in by CARET participants and staff to implement the decision. The most important activity was to draft and mail a letter to the participants informing them of the disappointing CARET results and asking them to stop taking the study vitamins and to return any unused study vitamins. The steering committee, with the support of the National Cancer Institute, planned to follow participants for disease endpoints and smoking behavior for 5 years. These activities led to smooth closure of active intervention and maintained high retention rates during the transition.

Epigenetic regulation plays a critical role in cell and tissue development and differentiation, is a known mechanism of carcinogenesis, and is altered by various exposures including cigarette smoking and age. Peripheral blood methylation represents a combination of these factors as well as blood cell type distributions that reflect underlying immunophenotypes. Hematopoiesis is programmed through epigenetic changes, and blood cell type-specific methylation markers can be leveraged to “fingerprint” cell type distributions. We examined associations between pre-diagnostic methylation markers in peripheral blood with overall lung cancer survival in very heavy smokers from the Beta Carotene and Retinol Efficacy Trial (CARET). CARET was a randomized, double-blinded, placebo-controlled chemoprevention trial of daily β-carotene and retinyl palmitate in smokers with ≥20 pack-years, and smokers who were occupationally exposed to asbestos. Methylation was successfully measured using the Illumina 850K EPIC BeadArray on average 5 years prior to diagnosis for 331 lung cancer cases, of whom 253 died during follow up (median survival 329 days). Cox proportional hazards regression models were used to examine the relationship between CpG-specific methylation and survival. Models were adjusted for age at blood draw, sex, race, enrollment year, placebo/active intervention, asbestos exposure, current/former smoking and time since quit, pack years, average number of cigarettes per day and histologic type, and were fit separately depending on the time between blood draw and lung cancer diagnosis: 0-3 years (n = 107), 3-5 years (n = 77), and 5+ years (n = 147). After adjusting for multiple comparisons by computing the false discovery rate (FDR) q-value, there were 1,028, 296, and 4 CpGs that were statistically significantly associated with survival (q ≤0.010) for samples collected 0-3 years, 3-5 years, and 5+ years before diagnosis, respectively. After controlling for blood cell type distributions, much larger numbers of CpGs were statistically significantly associated with survival: 10,481, 456, and 257, respectively. The top canonical pathways of CpGs identified in samples drawn 0-3 years prior to diagnosis included PTEN signaling (p = 1.1E-5) and PI3K signaling in B lymphoctyes (p = 3.7E-5). We observed that the number of methylated CpGs in peripheral blood that are associated with subsequent survival increases dramatically when measured closer to lung cancer diagnosis. As well, we observed that the number of methylated markers is increased by controlling for immunophenotype. Our study provides evidence that peripheral blood methylation markers measured many years prior to diagnosis may be associated with poor lung cancer survival, and that increasing changes in methylation over time may also be associated. This points to the critical role of the immune system, even prior to diagnosis, in influencing cancer outcomes. Citation Format: Jennifer A. Doherty, Xuan Zhang, Devin C. Koestler, Matt J. Barnett, Mark D. Thornquist, Gary E. Goodman, Carmen J. Marsit. Prediagnostic peripheral blood DNA methylation and lung cancer survival [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4958. doi:10.1158/1538-7445.AM2017-4958

BACKGROUND: Individual studies have suggested that some circulating fatty acids are associated with prostate cancer risk, but have not been large enough to provide precise estimates of associations, particularly by stage and grade of disease. METHODS: Principal investigators of prospective studies on circulating fatty acids and prostate cancer were invited to collaborate. Investigators provided individual participant data on circulating fatty acids (weight percent) and other characteristics of prostate cancer cases and controls. Prostate cancer risk by study-specific fifths of 14 fatty acids was estimated using multivariable-adjusted conditional logistic regression. All statistical tests were two-sided. RESULTS: Five thousand and ninety-eight case patients and 6649 control patients from seven studies with an average follow-up of 5.1 (SD = 3.3) years were included. Stearic acid (18:0) was inversely associated with total prostate cancer (odds ratio [OR] Q5 vs Q1 = 0.88, 95% confidence interval [CI] = 0.78 to 1.00, P trend = .043). Prostate cancer risk was, respectively, 14% and 16% greater in the highest fifth of eicosapentaenoic acid (20:5n-3) (OR = 1.14, 95% CI = 1.01 to 1.29, Ptrend = .001) and docosapentaenoic acid (22:5n-3) (OR = 1.16, 95% CI = 1.02 to 1.33, P trend = .003), but in each case there was heterogeneity between studies (P = .022 and P < .001, respectively). There was heterogeneity in the association between docosapentaenoic acid and prostate cancer by grade of disease (P = .006); the association was statistically significant for low-grade disease but not high-grade disease. The remaining 11 fatty acids were not statistically associated with total prostate cancer risk. CONCLUSION: There was no strong evidence that circulating fatty acids are important predictors of prostate cancer risk. It is not clear whether the modest associations of stearic, eicosapentaenoic, and docosapentaenoic acid are causal.

Background. This study aimed to assess the prevalence of weight-control behaviors and their associations with overall dietary intake among adults and adolescents. Methods. Participants included 3,832 adults and 459 adolescents from four regions of the United States. Cross-sectional data were collected on energy and nutrient intake, weight-control behaviors, body mass index (BMI), and sociodemographics. Results. Current weight-control behaviors were reported by 52.7% of the study population (adult women, 56.7%; adult men, 50.3%; adolescent girls, 44.0%; adolescent boys, 36.8%). Weight-control behaviors were consistently and positively associated with socioeconomic status among adults, but not among adolescents. Among “dieters,” unhealthy practices were reported by 22.7% of adult women, 21.3% of adult men, 30.4% of adolescent girls, and 18.5% of adolescent boys. Adults trying to control their weight reported healthier nutrient intakes than those not trying to control their weight, in particular when moderate weight-control methods were employed. Among adolescents, there were fewer differences across dieting status and these were not suggestive of healthier intakes among dieters than nondieters. Conclusions. Weight-control behaviors are reported by a large percentage of the population. Weight-control behaviors tend to be healthier among adults than among adolescents, in terms of the types of behaviors used and their impact on nutrient intakes. Obesity prevention interventions should emphasize the importance of using healthy weight-control practices.

Objective To identify the characteristics of people consuming olestra-containing foods when first introduced at a test-marketing site. Design Data are from the Olestra Postmarketing Surveillance Study (OPMSS). After the introduction of olestra into a large test-marketing site, study participants received 3 follow-up telephone calls, at 3-month intervals, in which they were questioned about their diets during the previous month. Subjects/setting 1,007 adults in Indianapolis, Ind, who participated in a baseline clinic visit (before introduction of olestra into the food market) and completed at least 2 of 3 follow-up telephone calls (after the introduction of olestra into the market). Statistical analyses performed Logistic regression was used to examine associations between olestra consumption and sociodemographic characteristics, health conditions, attitudes toward health and diet, and health-related behaviors. Results Olestra consumption on at least 1 of the follow-up telephone calls was reported by 41.5% of the study sample, and consumption on 2 or more telephone calls was reported by 20.0% of the sample. Factors associated with early adoption of olestra-containing foods included white ethnicity, higher education, overweight, absence of diabetes, attitudes indicative of diet and health concerns (eg, perceptions that there is a strong relationship between diet and disease), and a lower fat intake. Applications/conclusions In spite of the controversy surrounding the introduction of olestra into the food market, persons with attitudes indicative of diet and health concerns were likely to be early adopters of olestra-containing foods. Dietitians and other health care providers should inquire about intake levels of foods with fat substitutes and ensure that these foods are not being consumed in excessive amounts or being consumed instead of nutrient-dense foods that are naturally low in fat. J Am Diet Assoc. 2000; 100: 198–204.

The authors investigated associations of serum phospholipid n-3 and n-6 polyunsaturated fatty acids (PUFAs) and trans-fatty acids with prostate cancer risk, and whether myeloperoxidase G-463A (rs2333227) modified the associations in the Carotene and Retinol Efficacy Trial (CARET) (Seattle, Washington; Irvine, California; New Haven, Connecticut; San Francisco, California; Baltimore, Maryland; and Portland, Oregon, 1985-2003). Prerandomization sera were assayed for fatty acids among 641 men with incident prostate cancer (368 nonaggressive and 273 aggressive (stage III/IV or Gleason score ≥7)) and 1,398 controls. Overall, dihomo-γ-linolenic (quartiles 4 vs. 1: odds ratio (OR) = 0.66, 95% confidence interval (CI): 0.49, 0.95; P(trend) = 0.024) and docosatetraenoic (OR = 0.69, 95% CI: 0.46, 1.02; P(trend) = 0.011) acids were inversely associated with nonaggressive and aggressive prostate cancer risks, respectively. Among men with MPO GG, the genotype upregulating oxidative stress, quartiles 4 versus 1 eicosapentaenoic plus docosahexaenoic acids were suggestively associated with an increased risk of aggressive prostate cancer (OR = 1.66, 95% CI: 0.95, 2.92; P(trend) = 0.07). However, the association was the inverse among men with MPO GA/AA genotypes (P(interaction) = 0.011). Interactions were also observed for docosapentaenoic acid, total n-3 PUFAs, and arachidonic acid. MPO GA/AA vs. GG was associated with a 2-fold increase in aggressive prostate cancer risk among men with low (quartile 1) n-3 PUFAs. This study adds important evidence linking oxidative stress with prostate carcinogenesis.

Many carcinogens in tobacco smoke cause DNA damage, and some of that damage can be mitigated by the actions of DNA repair enzymes. In a case-control study nested within the Beta-Carotene and Retinol Efficacy Trial, a randomized chemoprevention trial in current and former heavy smokers, we examined whether lung cancer risk was associated with variation in 26 base excision repair, mismatch repair, and homologous recombination repair genes. Analyses were limited to Caucasians (744 cases, 1477 controls), and logistic regression was used to calculate odds ratios (ORs) and 95% confidence intervals (CIs) for individual SNPs and common haplotypes, with adjustment for matching factors. Lung cancer associations were observed (p

Background Imatinib has so far been the first-choice treatment in chronic myeloid leukemia with excellent results. However, only a proportion of patients achieve major molecular response – hence the need to find biological predictors of outcome to select the optimal therapeutic strategy now that more potent inhibitors are available. Design and methods We investigated a panel of 20 polymorphisms in 7 genes, potentially associated with the pharmacogenetics of imatinib, in a subset of 189 newly diagnosed chronic myeloid leukemia patients enrolled in the TOPS trial. Included in this analysis were polymorphisms in the transporters hOCT1, MDR1, ABCG2, OCTN1, and OATP1A2, and in the metabolizing genes CYP3A4 and CYP3A5. Results In the overall population, the OCTN1 C allele (rs1050152), a simple combination of polymorphisms in the hOCT1 gene and in the genes involved in imatinib uptake were significantly associated with major molecular response. The combination of polymorphisms in imatinib uptake was also significantly associated with complete molecular response. Analyses restricted to Caucasians highlighted the significant association of MDR1 CC (rs60023214) genotype with complete molecular response. Conclusions We demonstrate the usefulness of a pharmacogenetic approach for stratification of chronic myeloid leukemia patients in terms of likelihood to achieve major or complete molecular response on imatinib. This represents an attractive opportunity for therapy optimization, worth testing in clinical trials.

Since nucleotide excision repair (NER) is primarily responsible for detecting and removing bulky DNA lesions induced by tobacco smoke in the respiratory tract, single nucleotide polymorphisms (SNPs) in NER protein-encoding genes may influence lung cancer risk, particularly in smokers. Studies testing this hypothesis have produced inconsistent results, with most analyzing a few SNPs in relatively small population samples. In a study nested in the Beta- Carotene and Retinol Efficacy Trial, we examined 79 tag and previously reported risk-associated SNPs in the ERCC1, ERCC2, ERCC3, ERCC4, ERCC5, LIG1, POLE, XPA, and XPC genes in 744 lung cancer cases and 1,477 controls, all of whom were non-Hispanic white smokers. Using logistic regression, odds ratios (OR) and 95% confidence intervals (95% CI) were calculated to estimate lung cancer risk associated with SNP genotypes and haplotypes, adjusting for case-control matching factors. Lung cancer risk was modestly associated with LIG1 rs156640 (OR per G allele, 1.23; 95% CI, 1.08-1.40), rs156641 (OR per A allele, 1.23; 95% CI, 1.08-1.40), and rs8100261 (OR per A allele, 0.83; 95% CI, 0.76-0.98); XPA rs3176658 (OR per A allele, 0.83; 95% CI, 0.69-1.00); and ERCC2 rs50871 (OR per C allele, 1.15; 95% CI: 1.01-1.30). Associations with LIG1 and XPA, but not ERCC2, haplotypes were found. The results of this study and others suggest that inherited variants in LIG1 and possibly other NER genes may predispose to smoking-related lung cancer. Given that chance likely accounts for one or more of the associations observed, replication of our findings is needed.

The objective of this study was to test the association between calpain-10 (CAPN10), a diabetes susceptibility gene, with risk of pancreatic cancer (PC).DNA samples from 83 incident exocrine PC cases and 166 controls, all of whom were smokers, were genotyped for four markers of CAPN10 in a nested case-control study based on the Beta-Carotene and Retinol Efficacy Trial (CARET), a randomized chemoprevention trial of subjects at high risk of lung cancer. Controls were matched on sex, race, age, CARET intervention arm, duration of exposure to asbestos, and smoking history. Conditional logistic regression was used for statistical analyses.The minor allele of SNP-43 (rs3792267) in intron 3 was associated with increased risk of PC with an odds ratio of 1.57 (95%CI 1.03-2.38, p = 0.035) per allele. The three markers of the highest risk haplotype had an odds ratio of 1.98 (95%CI 1.12-3.49, p = 0.019) for risk of PC compared to the most common haplotype. There was no evidence of interaction between either of these associations by diabetes status.These results suggest that variation in CAPN10 may be associated with increased risk of PC among smokers. Thus, studies of genes associated with diabetes risk in PC are warranted in a larger population.

Background The complexity and heterogeneity of the human plasma proteome have presented significant challenges in the identification of protein changes associated with tumor development. Refined genetically engineered mouse (GEM) models of human cancer have been shown to faithfully recapitulate the molecular, biological, and clinical features of human disease. Here, we sought to exploit the merits of a well-characterized GEM model of pancreatic cancer to determine whether proteomics technologies allow identification of protein changes associated with tumor development and whether such changes are relevant to human pancreatic cancer. Methods and Findings Plasma was sampled from mice at early and advanced stages of tumor development and from matched controls. Using a proteomic approach based on extensive protein fractionation, we confidently identified 1,442 proteins that were distributed across seven orders of magnitude of abundance in plasma. Analysis of proteins chosen on the basis of increased levels in plasma from tumor-bearing mice and corroborating protein or RNA expression in tissue documented concordance in the blood from 30 newly diagnosed patients with pancreatic cancer relative to 30 control specimens. A panel of five proteins selected on the basis of their increased level at an early stage of tumor development in the mouse was tested in a blinded study in 26 humans from the CARET (Carotene and Retinol Efficacy Trial) cohort. The panel discriminated pancreatic cancer cases from matched controls in blood specimens obtained between 7 and 13 mo prior to the development of symptoms and clinical diagnosis of pancreatic cancer. Conclusions Our findings indicate that GEM models of cancer, in combination with in-depth proteomic analysis, provide a useful strategy to identify candidate markers applicable to human cancer with potential utility for early detection., Samir Hanash and colleagues identify proteins that are increased at an early stage of pancreatic tumor development in a mouse model and may be a useful tool in detecting early tumors in humans., Editors' Summary Background. Cancers are life-threatening, disorganized masses of cells that can occur anywhere in the human body. They develop when cells acquire genetic changes that allow them to grow uncontrollably and to spread around the body (metastasize). If a cancer is detected when it is still small and has not metastasized, surgery can often provide a cure. Unfortunately, many cancers are detected only when they are large enough to press against surrounding tissues and cause pain or other symptoms. By this time, surgical removal of the original (primary) tumor may be impossible and there may be secondary cancers scattered around the body. In such cases, radiotherapy and chemotherapy can sometimes help, but the outlook for patients whose cancers are detected late is often poor. One cancer type for which late detection is a particular problem is pancreatic adenocarcinoma. This cancer rarely causes any symptoms in its early stages. Furthermore, the symptoms it eventually causes—jaundice, abdominal and back pain, and weight loss—are seen in many other illnesses. Consequently, pancreatic cancer has usually spread before it is diagnosed, and most patients die within a year of their diagnosis. Why Was This Study Done? If a test could be developed to detect pancreatic cancer in its early stages, the lives of many patients might be extended. Tumors often release specific proteins—“cancer biomarkers”—into the blood, a bodily fluid that can be easily sampled. If a protein released into the blood by pancreatic cancer cells could be identified, it might be possible to develop a noninvasive screening test for this deadly cancer. In this study, the researchers use a “proteomic” approach to identify potential biomarkers for early pancreatic cancer. Proteomics is the study of the patterns of proteins made by an organism, tissue, or cell and of the changes in these patterns that are associated with various diseases. What Did the Researchers Do and Find? The researchers started their search for pancreatic cancer biomarkers by studying the plasma proteome (the proteins in the fluid portion of blood) of mice genetically engineered to develop cancers that closely resemble human pancreatic tumors. Through the use of two techniques called high-resolution mass spectrometry and acrylamide isotopic labeling, the researchers identified 165 proteins that were present in larger amounts in plasma collected from mice with early and/or advanced pancreatic cancer than in plasma from control mice. Then, to test whether any of these protein changes were relevant to human pancreatic cancer, the researchers analyzed blood samples collected from patients with pancreatic cancer. These samples, they report, contained larger amounts of some of these proteins than blood collected from patients with chronic pancreatitis, a condition that has similar symptoms to pancreatic cancer. Finally, using blood samples collected during a clinical trial, the Carotene and Retinol Efficacy Trial (a cancer-prevention study), the researchers showed that the measurement of five of the proteins present in increased amounts at an early stage of tumor development in the mouse model discriminated between people with pancreatic cancer and matched controls up to 13 months before cancer diagnosis. What Do These Findings Mean? These findings suggest that in-depth proteomic analysis of genetically engineered mouse models of human cancer might be an effective way to identify biomarkers suitable for the early detection of human cancers. Previous attempts to identify such biomarkers using human samples have been hampered by the many noncancer-related differences in plasma proteins that exist between individuals and by problems in obtaining samples from patients with early cancer. The use of a mouse model of human cancer, these findings indicate, can circumvent both of these problems. More specifically, these findings identify a panel of proteins that might allow earlier detection of pancreatic cancer and that might, therefore, extend the life of some patients who develop this cancer. However, before a routine screening test becomes available, additional markers will need to be identified and extensive validation studies in larger groups of patients will have to be completed. Additional Information. Please access these Web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.0050123. The MedlinePlus Encyclopedia has a page on pancreatic cancer (in English and Spanish). Links to further information are provided by MedlinePlus The US National Cancer Institute has information about pancreatic cancer for patients and health professionals (in English and Spanish) The UK charity Cancerbackup also provides information for patients about pancreatic cancer The Clinical Proteomic Technologies for Cancer Initiative (a US National Cancer Institute initiative) provides a tutorial about proteomics and cancer and information on the Mouse Proteomic Technologies Initiative

We examined the combined effect of circulating sex hormones and SRD5A2 V89L polymorphism on prostate cancer risk in a case-control study (300 cases and 300 controls) nested within the Carotene and Retinol Efficacy Trial. A moderate increase in risk associated with above-median serum levels of androstenedione and dehydroepiandrosterone sulfate (DHEAS) was present irrespective of V89L genotype. However, in L/L or V/L men, above-median DHEAS levels were associated with an increased risk of aggressive tumors [odds ratios (OR), 3.12; 95% confidence interval (95% CI), 1.28-7.63] but not of nonaggressive ones (OR, 0.56; 95% CI, 0.25-1.25). Above-median serum levels of free estradiol were associated with a lower risk, especially for aggressive cancer. The association with aggressive disease was more pronounced in men with a V/V genotype (OR, 0.34; 95% CI, 0.14-0.81), than in men with an L/L or V/L genotype (OR, 0.77; 95% CI, 0.37-1.60). Above-median levels of 3α-diol G were associated with an increased risk, but only in men with the L/L or V/L genotype (OR, 2.16; 95% CI, 1.31-3.56). The increase in risk in L/L and V/L men was restricted to aggressive tumors. Our study observed that only in men with the L/L or V/L genotype were increased serum levels of DHEAS and 3α-diol G positively associated with a higher risk of aggressive prostate cancer. Free estradiol levels were negatively associated with risk of aggressive prostate cancer in men with the V/V genotype. However, the absence of an overall association between V89L genotype and aggressive prostate cancer argues for a cautious interpretation of these observations. (Cancer Epidemiol Biomarkers Prev 2008;17(2):286–91)

Previous studies offer suggestive, but not definitive, evidence that total fat or specific fats may increase prostate cancer risk. This study investigates associations of dietary fat, meat, and dairy foods with prostate cancer risk among 12,025 men in the Carotene and Retinol Efficacy Trial (CARET). After 11 y of follow-up, 890 incident prostate cancers were reported and confirmed. Diet was assessed by a biannual FFQ. Cox proportional hazards models were used to estimate multivariate-adjusted hazard ratios (HR) of intake of fat and fat-related foods (meat and dairy) with prostate cancer incidence. Multiplicative interaction terms tested whether associations differed by family history, race, or smoking. Overall, fat was not associated with total, nonaggressive or aggressive prostate cancer. In subgroup analyses the HR for men with a family history of prostate cancer were 2.47 (95%CI = 0.96-6.37) and 2.61 (95% CI = 1.01-6.72) for total polyunsaturated fat (PUFA) and (n-6) PUFA for the 4th vs. 1st quartiles of intake, respectively. Red meat was not associated with total or aggressive prostate cancer. However, higher dairy intake had a statistically significant reduced risk of aggressive prostate cancer than lower dairy intake (HR = 0.59, 95% CI = 0.40-0.85). Dairy foods also protected current, but not former, smokers against aggressive cancer (HR = 0.42, 95% CI = 0.25-0.70). Our findings suggest that associations of dietary fat with prostate cancer risk may vary by type of fat or fat-containing food, and that risk may vary by host factors, including family history and smoking.

Oxidative stress, associated with aging and inflammation, is likely to play a role in the etiology of prostate cancer. We evaluated potential associations between gene variants that result in reduced neutralization of reactive oxygen species (ROS; MnSOD Ala-16Val, CAT −262 C>T, and GPX1 Pro200Leu) and prostate cancer risk among 724 men with incident prostate cancer who participated in the Carotene and Retinol Efficacy Trial (CARET) cohort, a randomized trial for the prevention of lung cancer among men with a history of smoking and/or asbestos exposure. Odds ratios (OR) and 95% confidence intervals (95% CI) were estimated by logistic regression. Nested case-control analyses included study participants with available DNA (n = 533 cases and 1,470 controls), matched for race, age, and length of follow-time. Overall, there were no associations between genotypes of MnSOD, CAT, and GPX1 and prostate cancer risk, although among men diagnosed before age 65, CAT TT genotype was associated with increased risk (OR, 2.0; 95% CI, 0.97-3.95). Further analyses stratified by factors related to environmental oxidative stress exposures did not modify associations. When calculating the number of risk alleles of MnSOD, CAT, and GPX1 hypothetically related to reduced protection against ROS, there was a nonsignificant relationship between prostate cancer and carriage of five or more risk alleles, in comparison to men with less than five risk alleles (OR, 2.0; 95% CI, 0.90-4.42). In conclusion, it does not seem that variants in MnSOD, CAT, or GPX1 have an influence on prostate cancer risk in this cohort of men who were smokers or exposed to asbestos, although it is possible that cumulative defects in protection from oxidative stress may result in increased risk of the disease. (Cancer Epidemiol Biomarkers Prev 2007;16(6):1115–20)