The contribution of common genetic variation to one or more established smoking behaviors was investigated in a joint analysis of two genome wide association studies (GWAS) performed as part of the Cancer Genetic Markers of Susceptibility (CGEMS) project in 2,329 men from the Prostate, Lung, Colon and Ovarian (PLCO) Trial, and 2,282 women from the Nurses' Health Study (NHS). We analyzed seven measures of smoking behavior, four continuous (cigarettes per day [CPD], age at initiation of smoking, duration of smoking, and pack years), and three binary (ever versus never smoking, ≤10 versus >10 cigarettes per day [CPDBI], and current versus former smoking). Association testing for each single nucleotide polymorphism (SNP) was conducted by study and adjusted for age, cohabitation/marital status, education, site, and principal components of population substructure. None of the SNPs achieved genome-wide significance (p<10−7) in any combined analysis pooling evidence for association across the two studies; we observed between two and seven SNPs with p<10−5 for each of the seven measures. In the chr15q25.1 region spanning the nicotinic receptors CHRNA3 and CHRNA5, we identified multiple SNPs associated with CPD (p<10−3), including rs1051730, which has been associated with nicotine dependence, smoking intensity and lung cancer risk. In parallel, we selected 11,199 SNPs drawn from 359 a priori candidate genes and performed individual-gene and gene-group analyses. After adjusting for multiple tests conducted within each gene, we identified between two and five genes associated with each measure of smoking behavior. Besides CHRNA3 and CHRNA5, MAOA was associated with CPDBI (gene-level p<5.4×10−5), our analysis provides independent replication of the association between the chr15q25.1 region and smoking intensity and data for multiple other loci associated with smoking behavior that merit further follow-up.
Metabolomic profiling has identified, sarcosine, a derivative of the amino acid glycine, as an important metabolite involved in the etiology or natural history of prostate cancer. We examined the association between serum sarcosine levels and risk of prostate cancer in 1122 cases (813 non-aggressive and 309 aggressive) and 1112 controls in the Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial. Sarcosine was quantified using high-throughput liquid chromatography-mass spectrometry. A significantly increased risk of prostate cancer was observed with increasing levels of sarcosine (odds ratio [OR] for the highest quartile of exposure [Q4] versus the lowest quartile [Q1] = 1.30, 95% confidence interval [CI]: 1.02, 1.65; P-trend 0.03). When stratified by disease aggressiveness, we observed a stronger association for non-aggressive cases (OR for Q4 versus Q1 = 1.44, 95% CI: 1.11, 1.88; P-trend 0.006) but no association for aggressive prostate cancer (OR for Q4 versus Q1 = 1.03, 95% CI: 0.73, 1.47; P-trend 0.89). Although not statistically significant, temporal analyses showed a stronger association between sarcosine and prostate cancer for serum collected closer to diagnosis, suggesting that sarcosine may be an early biomarker of disease. Interestingly, the association between sarcosine and prostate cancer risk was stronger among men with diabetes (OR = 2.66, 95% CI: 1.04, 6.84) compared with those without reported diabetes (OR = 1.23, 95% CI: 0.95-1.59, P-interaction = 0.01). This study found that elevated levels of serum sarcosine are associated with an increased prostate cancer risk and evidence to suggest that sarcosine may be an early biomarker for this disease.
Nasopharyngeal carcinoma (NPC) is rare in most of the world but common among southeast Asians. Since NPC is usually diagnosed at relatively young ages and most patients now survive, the issue of second primary tumors (SPTs) has become important. Previous studies of SPTs among NPC survivors have given conflicting results. Data on patients with NPC diagnosed between 1996 and 2002 were abstracted from the medical records of two Hong Kong oncology centers. SPT incidence in these patients was compared to that of Hong Kong's general population using standardized incidence ratios (SIR). Eight-four patients were observed to have at least 1 SPT and 92 total additional cancers (SIR = 1.93, 95% CI = 1.55-2.37). The excess risk was greater for women and patients under 40 at diagnosis. Significant excesses were found for tongue, lung, nasal and middle ear, and brain cancers. The pattern of sites at which the greatest excess risk occurred is consistent with the hypothesis that much of the excess is due to treatment effects. The greater excess risk among patients diagnosed before 40 points to possible genetic influences. More research is needed to determine the reasons for greater excess risk among women.
Background: The combined action of androgens and estrogens-specifically their balance-may play a role in prostate carcinogenesis, but existing evidence is sparse and inconsistent. We investigated associations between serum sex steroid hormones, including estrogen metabolites, and risk of aggressive prostate cancer.Methods: In a case-control study nested within the Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial cohort, we measured serum estrone, estradiol, and 13 estrogen metabolites, in the 2-, 4-, or 16-hydroxylation pathways, using an LC/MS-MS assay. Cases (n ¼ 195) were non-Hispanic white men ages 55 to 70 years when diagnosed with aggressive prostate cancer (stage III or IV and/or Gleason !7). Controls (n ¼ 195) were non-Hispanic white men without prostate cancer who were frequency matched to cases by age and year at blood draw, and time since baseline screen. Only men with serum testosterone and sex hormonebinding globulin measured previously were eligible. Logistic regression models were used to estimate ORs and 95% confidence intervals (95% CI).Results: Risk of aggressive prostate cancer was strongly inversely associated with estradiol:testosterone ratio (OR 4th quartile vs. 1st ¼ 0.27; 95% CI, 0.12-0.59, P trend ¼ 0.003) and positively associated with 2:16a-hydroxyestrone ratio (OR 4th quartile vs. 1st ¼ 2.44; 95% CI, 1.34-4.45, P trend ¼ 0.001). Individual estrogen metabolites were unrelated to risk.Conclusions: Our findings suggest that sex steroid hormones, specifically the estrogen-androgen balance, may be important in the development of aggressive prostate cancer.Impact: Improved understanding of the hormonal etiology of prostate cancer is critical for prevention and therapeutic interventions. Cancer Epidemiol Biomarkers Prev; 23(11); 2374-82. Ó2014 AACR.
A variety of biological processes, including steroid hormone secretion, have circadian rhythms, which are influenced by nine known circadian genes. Previously, we reported that certain variants in circadian genes were associated with risk for prostate cancer. To provide some biological insight into these findings, we examined the relationship of five variants of circadian genes, including NPAS2 (rs2305160:G>A), PER1 (rs2585405:G>C), CSNK1E (rs1005473:A>C), PER3 (54-bp repeat length variant), and CRY2 (rs1401417:G>C), with serum levels of sex steroids and insulin-like growth factor (IGF)-I and IGF-binding protein 3 (IGFBP3) in 241 healthy elderly Chinese men (mean age of 71.5). Age-adjusted and waist-to-hip ratioadjusted ANOVA followed by likelihood ratio tests (LRT) showed that the NPAS2 variant A allele was associated with lower free and bioavailable testosterone (P LRT = 0.02 and 0.01, respectively) compared with the GG genotype. In addition, the PER1 variant was associated with higher serum levels of sex hormonebinding globulin levels (P trend = 0.03), decreasing 5A-androstane-3A, 17B-diol glucuronide levels (P trend = 0.02), and decreasing IGFBP3 levels (P trend = 0.05). Furthermore, the CSNK1E variant C allele was associated with higher testosterone to dihydrotestosterone ratios (P LRT = 0.01) compared with the AA genotype, whereas the longer PER3 repeat was associated with higher serum levels of IGF-I (P LRT = 0.03) and IGF-I to IGFBP3 ratios (P LRT = 0.04). The CRY2 polymorphism was not associated with any biomarkers analyzed. Our findings, although in need of confirmation, suggest that variations in circadian genes are associated with serum hormone levels, providing biological support for the role of circadian genes in hormone-related cancers. (Cancer Epidemiol Biomarkers Prev 2008;17(11):3268 -73)
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.