Citations

ABSTRACT Campylobacter jejuni and Salmonella , Shigella , and Yersinia species (along with Shiga toxin-producing Escherichia coli ) are the most common causes of acute bacterial diarrheal disease in the United States. Current detection techniques are time-consuming, limiting usefulness for patient care. We developed and validated a panel of rapid PCR assays for the detection and identification of C. jejuni , C. coli , Salmonella , and Yersinia species and Shigella and enteroinvasive E. coli in stool samples. A total of 392 archived stool specimens, previously cultured for enteric pathogens, were evaluated by PCR. Overall, 104 stool specimens had been culture positive ( C. jejuni / coli [ n = 51], Salmonella species [ n = 42], Shigella species [ n = 6], and Yersinia species [ n = 5]). Compared to culture, the overall sensitivity and specificity of PCR detection of these organisms were 92 and 98% (96/104 and 283/288), respectively, from fresh or Cary Blair stool ( P = 0.41); 87 and 98% (41/47 and 242/246), respectively, from fresh stool ( P = 0.53); and 96 and 98% (55/57 and 41/42), respectively, from Cary Blair stool ( P = 0.56). For individual genera, PCR was as sensitive as the culture method, with the exception of Salmonella culture using selenite enrichment for which PCR was less sensitive than culture from fresh, but not Cary Blair ( P = 0.03 and 1.00, respectively) stools. This PCR assay panel for the rapid diagnosis of acute infectious bacterial diarrheal pathogens has a sensitivity and specificity equivalent to that of culture for stools in Cary Blair transport medium. Paired with reflexive culture of stools testing positive, this should provide an improvement in care for patients with acute infectious diarrheal disease.

Abstract Background: There is strong and consistent evidence that a genetic component contributes to the etiology of chronic lymphocytic leukemia (CLL). A recent genome-wide association study of CLL identified seven genetic variants that increased the risk of CLL within a European population. Methods: We evaluated the association of these variants, or variants in linkage disequilibrium with these variants, with CLL risk in an independent sample of 438 CLL cases and 328 controls. Results: Of these seven single nucleotide polymorphisms (SNP), six had P trend < 0.05 and had estimated odds ratios (OR) that were strikingly comparable to those of the previous study. Associations were seen for rs9378805 [OR, 1.47; 95% confidence intervals (CI), 1.19-1.80; P trend = 0.0003] near IRF4 and rs735665 near GRAMD1B (OR, 1.47; 95% CI, 1.14-1.89; P trend = 0.003). However, no associations (P > 0.05) were found for rs11083846, nor were any found for any SNP in linkage disequilibrium with rs11083846. Conclusions: Our results confirm the previous findings and further support the role of a genetic basis in the etiology of CLL; however, more research is needed to elucidate the causal SNP(s) and the potential manner in which these SNPs or linked SNPs function in CLL pathogenesis. Cancer Epidemiol Biomarkers Prev; 19(4); 1098–102. ©2010 AACR.

Abstract Aberrant glycosylation is a well-described hallmark of cancer. In a previous ovarian cancer case control study that examined polymorphisms in 26 glycosylation-associated genes, we found strong statistical evidence (P = 0.00017) that women who inherited two copies of a single-nucleotide polymorphism in the UDP-N-acetylgalactosamine:polypeptide N-acetylgalactosaminyltransferase, GALNT1, had decreased ovarian cancer risk. The current study attempted to replicate this observation. The GALNT1 single-nucleotide polymorphism rs17647532 was genotyped in 6,965 cases and 8,377 controls from 14 studies forming the Ovarian Cancer Association Consortium. The fixed effects estimate per rs17647532 allele was null (odds ratio, 0.99; 95% confidence interval, 0.92-1.07). When a recessive model was fit, the results were unchanged. Test for hetero geneity of the odds ratios revealed consistency across the 14 replication sites but significant differences compared with the original study population (P = 0.03). This study underscores the need for replication of putative findings in genetic association studies. Cancer Epidemiol Biomarkers Prev; 19(2); 600–4

Abstract We genotyped 13 single nucleotide polymorphisms (SNPs) in the estrogen receptor alpha gene (ESR1) region in three population-based case-control studies of epithelial ovarian cancer conducted in the United States, comprising a total of 1,128 and 1,866 non-Hispanic white invasive cases and controls, respectively. A SNP 19 kb downstream of ESR1 (rs2295190, G-to-T change) was associated with invasive ovarian cancer risk, with a per-T-allele odds ratio (OR) of 1.24 [95% confidence interval (CI), 1.06-1.44, P = 0.006]. rs2295190 is a nonsynonymous coding SNP in a neighboring gene called spectrin repeat containing, nuclear envelope 1 (SYNE1), which is involved in nuclear organization and structural integrity, function of the Golgi apparatus, and cytokinesis. An isoform encoded by SYNE1 has been reported to be downregulated in ovarian and other cancers. rs2295190 was genotyped in an additional 12 studies through the Ovarian Cancer Association Consortium, with 5,279 invasive epithelial cases and 7,450 controls. The per-T-allele OR for this 12-study set was 1.09 (95% CI, 1.02-1.17; P = 0.017). Results for the serous subtype in the 15 combined studies were similar to those overall (n = 3,545; OR, 1.09; 95% CI, 1.01-1.18; P = 0.025), and our findings were strongest for the mucinous subtype (n = 447; OR, 1.32; 95% CI, 1.11-1.58; P = 0.002). No association was observed for the endometrioid subtype. In an additional analysis of 1,459 borderline ovarian cancer cases and 7,370 controls, rs2295190 was not associated with risk. These data provide suggestive evidence that the rs2295190 T allele, or another allele in linkage disequilibrium with it, may be associated with increased risk of invasive ovarian cancer. Cancer Epidemiol Biomarkers Prev; 19(1); 244–50

Abstract Background: Multiple recent genome-wide studies of single nucleotide polymorphisms (SNP) reported associations between candidate chromosome loci and lung cancer susceptibility. We evaluated five of the top candidate SNPs (rs402710, rs2736100, rs4324798, rs16969968, and rs8034191) for their effects on lung cancer risk and overall survival. Methods: Over 1,700 cases and 2,200 controls were included in this study. Seven independent, complementary case-control data sets were tested for risk assessment encompassing cigarette smokers and never smokers, using unrelated controls and unaffected full-sibling controls. Five patient groups were tested for survival prediction stratified by smoking status, histology subtype, and treatment. Results: After considering a history of chronic obstructive pulmonary disease as a risk factor altering lung cancer risk and comparing to sibling controls, none of the five SNPs remained significant. However, the variant rs4324798 was significant in predicting overall survival (hazard ratio, 0.46; 95% confidence interval, 0.30-0.73; P = 0.001) in small cell lung cancer. Conclusions: None of the five candidate SNPs in lung cancer risk can be confirmed in our study. The previously reported association could be explained by disparity in tobacco smoke exposure and chronic obstructive pulmonary disease history between cases and controls. Instead, we found rs4324798 to be an independent predictor in small cell lung cancer survival, warranting further elucidation of the underlying mechanisms.Cancer Epidemiol Biomarkers Prev; 19(1); 240–4

Abstract Prostate cancer, a complex disease, can be relatively harmless or extremely aggressive. To identify candidate genes involved in causal pathways of aggressive prostate cancer, we implemented a systems biology approach by combining differential expression analysis and coexpression network analysis to evaluate transcriptional profiles using lymphoblastoid cell lines from 62 prostate cancer patients with aggressive phenotype (Gleason grade ≥ 8) and 63 prostate cancer patients with nonaggressive phenotype (Gleason grade ≤ 5). From 13,935 mRNA genes and 273 microRNAs (miRNA) tested, we identified significant differences in 1,100 mRNAs and 7 miRNAs with a false discovery rate (FDR) of <0.01. We also identified a coexpression module demonstrating significant association with the aggressive phenotype of prostate cancer (P = 3.67 × 10−11). The module of interest was characterized by overrepresentation of cell cycle–related genes (FDR = 3.50 × 10−50). From this module, we further defined 20 hub genes that were highly connected to other genes. Interestingly, 5 of the 7 differentially expressed miRNAs have been implicated in cell cycle regulation and 2 (miR-145 and miR-331-3p) are predicted to target 3 of the 20 hub genes. Ectopic expression of these two miRNAs reduced expression of target hub genes and subsequently resulted in cell growth inhibition and apoptosis. These results suggest that cell cycle is likely to be a molecular pathway causing aggressive phenotype of prostate cancer. Further characterization of cell cycle–related genes (particularly, the hub genes) and miRNAs that regulate these hub genes could facilitate identification of candidate genes responsible for the aggressive phenotype and lead to a better understanding of prostate cancer etiology and progression. [Cancer Res 2009;69(24):9490–7]

Abstract Background: Exposure to secondhand smoke during adulthood has detrimental health effects, including increased lung cancer risk. Compared with adults, children may be more susceptible to secondhand smoke. This susceptibility may be exacerbated by alterations in inherited genetic variants of innate immunity genes. We hypothesized a positive association between childhood secondhand smoke exposure and lung cancer risk that would be modified by genetic polymorphisms in the mannose binding lectin-2 (MBL2) gene resulting in well-known functional changes in innate immunity. Methods: Childhood secondhand smoke exposure and lung cancer risk was assessed among men and women in the ongoing National Cancer Institute-Maryland Lung Cancer (NCI-MD) study, which included 624 cases and 348 controls. Secondhand smoke history was collected via in-person interviews. DNA was used for genotyping the MBL2 gene. To replicate, we used an independent case-control study from Mayo Clinic consisting of 461 never smokers, made up of 172 cases and 289 controls. All statistical tests were two-sided. Results: In the NCI-MD study, secondhand smoke exposure during childhood was associated with increased lung cancer risk among never smokers [odds ratio (OR), 2.25; 95% confidence interval (95% CI), 1.04-4.90]. This was confirmed in the Mayo study (OR, 1.47; 95% CI, 1.00-2.15). A functional MBL2 haplotype associated with high circulating levels of MBL and increased MBL2 activity was associated with increased lung cancer risk among those exposed to childhood secondhand smoke in both the NCI-MD and Mayo studies (OR, 2.52; 95% CI, 1.13-5.60, and OR, 2.78; 95% CI, 1.18-3.85, respectively). Conclusions: Secondhand smoke exposure during childhood is associated with increased lung cancer risk among never smokers, particularly among those possessing a haplotype corresponding to a known overactive complement pathway of the innate immune system. (Cancer Epidemiol Biomarkers Prev 2009;18(12):3375–83)

Abstract Multiple genome-wide association studies have identified several susceptibility variants for colon cancer at 8q24. However, the functional roles of these variants have yet to be elucidated. Here, we evaluated the potential role of these markers in tumor progression and examined association with commonly observed structural abnormalities in this region, c-MYC amplification and chromosome fragility at FRA8C and FRA8D. We first replicated the previously reported association by testing 1,178 cases and 1,009 clinic-based controls with eight markers localized to three specific regions at 8q24. We observed significant associations with colon cancer risk with markers rs13254738 (ordinal odds ratio, 0.82; 95% confidence interval, 0.072-0.94; Ptrend = 0.0037) and rs6983267 (ordinal odds ratio, 1.17; 95% confidence interval, 1.03-1.32, Ptrend = 0.013). Survival analysis was done using a separate set of 460 cases to evaluate the clinical significance of these markers. Overall, univariate analysis did not detect survival differences for any of the markers. We also tested a subset of the 460 cases (n = 380) for structural abnormalities at or near the c-MYC locus using fluorescence in situ hybridization analysis. Furthermore, we evaluated a small number of cases homozygous for the rs6983267 alleles to test for differences in fragile site induction. None of the 8q markers correlated with amplification at the c-MYC locus as detected by fluorescence in situ hybridization, and no clear pattern of breakage was observed at the FRA8C and FRA8D sites. In this study, we confirm the association for several single nucleotide polymorphisms at 8q24 in colon cancer but have not detected any structural role relating to c-MYC amplification or chromosomal fragility. Finally, these risk alleles do not seem to be associated with survival. (Cancer Epidemiol Biomarkers Prev 2009;18(9):2492–500)

Abstract Background: Inherited risk of pancreatic cancer has been associated with mutations in several genes, including BRCA2, CDKN2A (p16), PRSS1, and PALB2. We hypothesized that common variants in these genes, single nucleotide polymorphisms (SNP), may also influence risk for pancreatic cancer development. Methods: A clinic-based case-control study in non-Hispanic white persons compared 1,143 patients with pancreatic adenocarcinoma with 1,097 healthy controls. Twenty-eight genes directly and indirectly involved in the Fanconi/BRCA pathway (includes BRCA1, BRCA2, and PALB2) were identified and 248 tag SNPs were selected. In addition, 11 SNPs in CDKN2A, PRSS1, and PRSS2 were selected. Association studies were done at the gene level by principal components analysis, whereas recursive partitioning analysis was used to investigate pathway effects. At the individual SNP level, adjusted additive, dominant, and recessive models were investigated, and gene-environment interactions were also assessed. Results: Gene level analyses showed no significant association of any genes with altered pancreatic cancer risk. Multiple single SNP analyses showed associations, which will require replication. Exploratory pathway analyses by recursive partitioning showed no association between SNPs and risk for pancreatic cancer. Conclusion: In a candidate gene and pathway SNP association study analysis, common variations in the Fanconi/BRCA pathway and other candidate familial pancreatic cancer genes are not associated with risk for pancreatic cancer. Cancer Epidemiol Biomarkers Prev 2009;18(9):2549–52)

Abstract Background: Nucleotide excision repair is a vital response to DNA damage, including damage from tobacco exposure. Single nucleotide polymorphisms (SNP) in the nucleotide excision repair pathway may encode alterations that affect DNA repair function and therefore influence the risk of pancreatic cancer development. Methods: A clinic-based case-control study in non-Hispanic white persons compared 1,143 patients with pancreatic adenocarcinoma with 1,097 healthy controls. Twenty-seven genes directly and indirectly involved in the nucleotide excision repair pathway were identified and 236 tag-SNPs were selected from 26 of these (one had no SNPs identified). Association studies were done at the gene level by principal components analysis, whereas recursive partitioning analysis was utilized to identify potential gene-gene and gene-environment interactions within the pathway. At the individual SNP level, adjusted additive, dominant, and recessive models were investigated, and gene-environment interactions were also assessed. Results: Gene level analyses showed an association of the MMS19L genotype (chromosome 10q24.1) with altered pancreatic cancer risk (P = 0.023). Haplotype analysis of MMS19L also showed a significant association (P = 0.0132). Analyses of seven individual SNPs in this gene showed both protective and risk associations for minor alleles, broadly distributed across patient subgroups defined by smoking status, sex, and age. Conclusion: In a candidate pathway SNP association study analysis, common variation in a nucleotide excision repair gene, MMS19L, was associated with the risk of pancreatic cancer. (Cancer Epidemiol Biomarkers Prev 2009;18(4):1295–302)