Citations

Abstract Purpose: We have previously mapped a major susceptibility locus influencing familial lung cancer risk to chromosome 6q23-25. However, the causal gene at this locus remains undetermined. In this study, we further refined this locus to identify a single candidate gene, by fine mapping using microsatellite markers and association studies using high-density single nucleotide polymorphisms (SNP). Experimental Design: Six multigenerational families with five or more affected members were chosen for fine-mapping the 6q linkage region using microsatellite markers. For association mapping, we genotyped 24 6q-linked cases and 72 unrelated noncancer controls from the Genetic Epidemiology of Lung Cancer Consortium resources using the Affymetrix 500K chipset. Significant associations were validated in two independent familial lung cancer populations: 226 familial lung cases and 313 controls from the Genetic Epidemiology of Lung Cancer Consortium, and 154 familial cases and 325 controls from Mayo Clinic. Each familial case was chosen from one high-risk lung cancer family that has three or more affected members. Results: A region-wide scan across 6q23-25 found significant association between lung cancer susceptibility and three single nucleotide polymorphisms in the first intron of the RGS17 gene. This association was further confirmed in two independent familial lung cancer populations. By quantitative real-time PCR analysis of matched tumor and normal human tissues, we found that RGS17 transcript accumulation is highly and consistently increased in sporadic lung cancers. Human lung tumor cell proliferation and tumorigenesis in nude mice are inhibited upon knockdown of RGS17 levels. Conclusion: RGS17 is a major candidate for the familial lung cancer susceptibility locus on chromosome 6q23-25.

The authors evaluated existing and new criteria for defining the medical necessity for breast reduction surgery. Two cohorts of women (those requesting breast reduction surgery [N = 266] and a group of controls [N = 184]) completed a questionnaire including breast-specific symptom severity, the Short Form 36, the EuroQol, the McGill Pain Questionnaire, and the Multidimensional Body Self Relations Questionnaire. To evaluate prediction validity, the most widely accepted decision criteria and a new definition of medical necessity were applied to the data set to determine whether women meeting the definition had more favorable outcomes than those who did not as measured by validated self-report instruments. For existing criteria, women not meeting and meeting the criterion gained equal benefit from surgery. Women meeting the new definition (2 of 7 physical symptoms all or most of the time) had significantly greater improvement scores on 4 of the 5 health burden measures compared to women not meeting this definition. The authors conclude that medical necessity for breast reduction surgery is better defined by self-report of symptoms than by existing criteria.

Abstract The p53 protein is critical for multiple cellular functions including cell growth and DNA repair. We assessed whether polymorphisms in the region encoding TP53 were associated with risk of invasive ovarian cancer. The study population includes a total of 5,206 invasive ovarian cancer cases (2,829 of which were serous) and 8,790 controls from 13 case-control or nested case-control studies participating in the Ovarian Cancer Association Consortium (OCAC). Three of the studies performed independent discovery investigations involving genotyping of up to 23 single nucleotide polymorphisms (SNP) in the TP53 region. Significant findings from this discovery phase were followed up for replication in the other OCAC studies. Mixed effects logistic regression was used to generate posterior median per allele odds ratios (OR), 95% probability intervals (PI), and Bayes factors (BF) for genotype associations. Five SNPs showed significant associations with risk in one or more of the discovery investigations and were followed up by OCAC. Mixed effects analysis confirmed associations with serous invasive cancers for two correlated (r2 = 0.62) SNPs: rs2287498 (median per allele OR, 1.30; 95% PI, 1.07–1.57) and rs12951053 (median per allele OR, 1.19; 95% PI, 1.01–1.38). Analyses of other histologic subtypes suggested similar associations with endometrioid but not with mucinous or clear cell cancers. This large study provides statistical evidence for a small increase in risk of ovarian cancer associated with common variants in the TP53 region. [Cancer Res 2009;69(6):2349–57]

Abstract Polymorphisms in genes critical to cell cycle control are outstanding candidates for association with ovarian cancer risk; numerous genes have been interrogated by multiple research groups using differing tagging single-nucleotide polymorphism (SNP) sets. To maximize information gleaned from existing genotype data, we conducted a combined analysis of five independent studies of invasive epithelial ovarian cancer. Up to 2,120 cases and 3,382 controls were genotyped in the course of two collaborations at a variety of SNPs in 11 cell cycle genes (CDKN2C, CDKN1A, CCND3, CCND1, CCND2, CDKN1B, CDK2, CDK4, RB1, CDKN2D, and CCNE1) and one gene region (CDKN2A-CDKN2B). Because of the semi-overlapping nature of the 123 assayed tagging SNPs, we performed multiple imputation based on fastPHASE using data from White non-Hispanic study participants and participants in the international HapMap Consortium and National Institute of Environmental Health Sciences SNPs Program. Logistic regression assuming a log-additive model was done on combined and imputed data. We observed strengthened signals in imputation-based analyses at several SNPs, particularly CDKN2A-CDKN2B rs3731239; CCND1 rs602652, rs3212879, rs649392, and rs3212891; CDK2 rs2069391, rs2069414, and rs17528736; and CCNE1 rs3218036. These results exemplify the utility of imputation in candidate gene studies and lend evidence to a role of cell cycle genes in ovarian cancer etiology, suggest a reduced set of SNPs to target in additional cases and controls. (Cancer Epidemiol Biomarkers Prev 2009;18(3):935–44)

AbstractOver 22,000 cases of ovarian cancer were diagnosed in 2007 in the United States, but only a fraction of them can be attributed to mutations in highly penetrant genes such as BRCA1. To determine whether low-penetrance genetic variants contribute to ovarian cancer risk, we genotyped 1,536 single nucleotide polymorphisms (SNP) in several candidate gene pathways in 848 epithelial ovarian cancer cases and 798 controls in the North Carolina Ovarian Cancer Study (NCO) using a customized Illumina array. The inflammation gene interleukin-18 (IL18) showed the strongest evidence for association with epithelial ovarian cancer in a gene-by-gene analysis (P = 0.002) with a <25% chance of being a false-positive finding (q value = 0.240). Using a multivariate model search algorithm over 11 IL18 tagging SNPs, we found that the association was best modeled by rs1834481. Further, this SNP uniquely tagged a significantly associated IL18 haplotype and there was an increased risk of epithelial ovarian cancer per rs1834481 allele (odds ratio, 1.24; 95% confidence interval, 1.06-1.45). In a replication stage, 12 independent studies from the Ovarian Cancer Association Consortium (OCAC) genotyped rs1834481 in an additional 5,877 cases and 7,791 controls. The fixed effects estimate per rs1834481 allele was null (odds ratio, 0.99; 95% confidence interval, 0.94-1.05) when data from the 12 OCAC studies were combined. The effect estimate remained unchanged with the addition of the initial North Carolina Ovarian Cancer Study data. This analysis shows the importance of consortia, like the OCAC, in either confirming or refuting the validity of putative findings in studies with smaller sample sizes. (Cancer Epidemiol Biomarkers Prev 2008;17(12):3567–72)

Abstract The mitochondrion, conventionally thought to be an organelle specific to energy metabolism, is in fact multifunctional and implicated in many diseases, including cancer. To evaluate whether mitochondria-related genes are associated with increased risk for prostate cancer, we genotyped 24 single-nucleotide polymorphisms (SNP) within the mitochondrial genome and 376 tagSNPs localized to 78 nuclear-encoded mitochondrial genes. The tagSNPs were selected to achieve ≥80% coverage based on linkage disequilibrium. We compared allele and haplotype frequencies in ∼1,000 prostate cancer cases with ∼500 population controls. An association with prostate cancer was not detected for any of the SNPs within the mitochondrial genome individually or for 10 mitochondrial common haplotypes when evaluated using a global score statistic. For the nuclear-encoded genes, none of the tagSNPs were significantly associated with prostate cancer after adjusting for multiple testing. Nonetheless, we evaluated unadjusted P values by comparing our results with those from the Cancer Genetic Markers of Susceptibility (CGEMS) phase I data set. Seven tagSNPs had unadjusted P ≤ 0.05 in both our data and in CGEMS (two SNPs were identical and five were in strong linkage disequilibrium with CGEMS SNPs). These seven SNPs (rs17184211, rs4147684, rs4233367, rs2070902, rs3829037, rs7830235, and rs1203213) are located in genes MTRR, NDUFA9, NDUFS2, NDUFB9, and COX7A2, respectively. Five of the seven SNPs were further included in the CGEMS phase II study; however, none of the findings for these were replicated. Overall, these results suggest that polymorphisms in the mitochondrial genome and those in the nuclear-encoded mitochondrial genes evaluated are not substantial risk factors for prostate cancer. (Cancer Epidemiol Biomarkers Prev 2008;17(12):3558–66)

Abstract Non-Hodgkin's lymphoma (NHL) is a cancer closely associated with immune function, and the tumor necrosis factor (TNF) G-308A promoter polymorphism, which influences immune function and regulation, was recently reported by the InterLymph Consortium to be associated with NHL risk. TNF signaling activates the nuclear factor-κB (NF-κB) canonical pathway, leading to transcriptional activation of multiple genes that influence inflammation and immune response. We hypothesized that, in addition to TNF signaling, common genetic variation in genes from the NF-κB canonical pathway may affect risk of NHL. We genotyped 54 single nucleotide polymorphisms (SNP) within TNF, lymphotoxin A LTA, and nine NF-κB genes from the canonical pathway (TNFRSF1A, TRADD, TRAF2, TRAF5, RIPK1, CHUK, IKBKB, NFKB1, and REL) in a clinic-based study of 441 incident cases and 475 frequency-matched controls. Tagging SNPs were selected from HapMap supplemented by putative functional SNPs for LTA/TNF. We used principal components and haplo.stats to model gene-level associations and logistic regression to model SNP-level associations. Compared with the wild-type (GG), the AA genotype for the TNF promoter polymorphism G-308A (rs1800629) was associated with increased risk of NHL [odds ratio (OR), 2.14; 95% confidence interval (95% CI), 0.94-4.85], whereas the GA genotype was not (OR, 1.00; 95% CI, 0.74-1.34). This association was similar for follicular lymphoma and diffuse large B-cell lymphoma. A previously reported LTA/TNF haplotype was also associated with NHL risk. In gene-level analysis of the NF-κB pathway, only NFKB1 showed a statistically significant association with NHL (P = 0.049), and one NFKB1 tagSNP (rs4648022) was associated with NHL risk overall (ordinal OR, 0.59; 95% CI, 0.41-0.84; Ptrend = 0.0037) and for each of the common subtypes. In conclusion, we provide additional evidence for the role of genetic variation in TNF and LTA SNPs and haplotypes with risk of NHL and also provide some of the first preliminary evidence for an association of genetic variation in NFKB1, a downstream target of TNF signaling, with risk of NHL. (Cancer Epidemiol Biomarkers Prev 2008;17(11):3161–9)

Abstract Pancreatic cancer is a highly lethal malignancy, and the majority of patients succumb to the disease within 2 years. We evaluated the role of variants of mitochondrial DNA and mitochondrial haplogroups in predicting prognosis of patients with pancreatic cancer. A total of 24 mitochondrial single nucleotide polymorphisms were genotyped in 990 patients with pancreatic cancer. After adjusting for covariates and multiple comparisons, no association between any of the mitochondrial single nucleotide polymorphisms or haplogroups and survival was observed. (Cancer Epidemiol Biomarkers Prev 2008;17(9):2512–3)