Abstract P1-04-08: Non-nuclear SUMO dynamics regulate mammary epithelial cell transformation

Objective: The reversible SUMO-posttranslational modification of protein substrates regulates various cellular processes and consistently is important for normal cell physiology. Disruption of SUMO enzymatic components supports onset of various pathophysiological disorders, including cancer. Our recent study identified a splicing event that differentially modulates expression of 2 SENP7 isoforms. The novel SENP7 variant SENP7S is the predominant SUMO protease in normal mammary epithelia; however onset of precancerous ductal carcinoma in situ (DCIS) reduces SENP7S significantly and stays low in all breast cancer (BCa) subtypes. Inversely, the full-length SENP7L isoform is upregulated in BCa and directly leads to BCa metastasis. Unlike SENP7L, SENP7S isoform contribution to carcinogenesis is unclear. Our objective is to define the biological function of this novel deSUMOylase SENP7S in normal versus cancerous epithelial cells.

Results: Consistently with mRNA levels, protein levels of the 2 SENP7 isoforms are also inversely expressed in human BCa versus normal mammary epithelia. SENP7S is localized in the cytosol of MCF10-2A unlike other SUMO proteases including SENP7L that are predominantly nuclear enzymes. Beta-catenin and a component of the Beta-catenin destruction complex, Axin1 are substrates for SENP7S catalytic activity as in the absence of SENP7S, Beta-catenin and Axin 1 are both SUMOylated. Consistently, SENP7S regulates Beta-catenin signaling pathway. SUMOylated Axin1 loses its interaction with Beta-catenin, allowing the Beta-catenin to escape ubiquitylation and further proteasomal degradation. SUMOylated Beta-catenin translocates to the nucleus and activates multiple target genes that potentiate cell proliferation. Increase in cell proliferation and anchorage dependent growth of non-cancerous MCF10-2A cells was observed with inhibition of SENP7S. Additionally, SENP7S depletion potentiates anchorage independent growth of MCF10-2A with significantly greater number and size of spheroids. In comparison to the control. Loss of SENP7S also potentiates the self-renewal properties of the cells, indicative of mammary epithelial cell transformation.

Conclusion: SENP7S modulates Beta-catenin stability and signaling and consequently is critical for normal mammary epithelial cell physiology. Loss of SENP7S, as observed in DCIS, initiates mammary epithelial cell transformation.

Citation Format: Karami S, Lin F-M, Kumar S, Ren J, Bahnassy S, Bawa-Khalfe T. Non-nuclear SUMO dynamics regulate mammary epithelial cell transformation [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P1-04-08.

Telomere structure and maintenance gene variants and risk of five cancer types

Telomeres cap chromosome ends, protecting them from degradation, double-strand breaks, and end-to-end fusions. Telomeres are maintained by telomerase, a reverse transcriptase encoded by TERT, and an RNA template encoded by TERC. Loci in the TERT and adjoining CLPTM1L region are associated with risk of multiple cancers. We therefore investigated associations between variants in 22 telomere structure and maintenance gene regions and colorectal, breast, prostate, ovarian, and lung cancer risk. We performed subset-based meta-analyses of 204,993 directly-measured and imputed SNPs among 61,851 cancer cases and 74,457 controls of European descent. Independent associations for SNP minor alleles were identified using sequential conditional analysis (with gene-level p value cutoffs ≤3.08 × 10-5 ). Of the thirteen independent SNPs observed to be associated with cancer risk, novel findings were observed for seven loci. Across the DCLRE1B region, rs974494 and rs12144215 were inversely associated with prostate and lung cancers, and colorectal, breast, and prostate cancers, respectively. Across the TERC region, rs75316749 was positively associated with colorectal, breast, ovarian, and lung cancers. Across the DCLRE1B region, rs974404 and rs12144215 were inversely associated with prostate and lung cancers, and colorectal, breast, and prostate cancers, respectively. Near POT1, rs116895242 was inversely associated with colorectal, ovarian, and lung cancers, and RTEL1 rs34978822 was inversely associated with prostate and lung cancers. The complex association patterns in telomere-related genes across cancer types may provide insight into mechanisms through which telomere dysfunction in different tissues influences cancer risk.

Risk of Renal Cell Carcinoma Among Kidney Transplant Recipients in the United States

Renal cell carcinoma (RCC) is a common malignancy following kidney transplantation. We describe RCC risk and examine RCC risk factors among US kidney recipients (1987-2010). The Transplant Cancer Match Study links the US transplant registry with 15 cancer registries. Standardized incidence ratios (SIRs) were used to compare RCC risk (overall and for clear cell [ccRCC] and papillary subtypes) to the general population. Associations with risk factors were assessed using Cox models. We identified 683 RCCs among 116 208 kidney recipients. RCC risk was substantially elevated compared with the general population (SIR 5.68, 95% confidence interval 5.27-6.13), especially for papillary RCC (SIR 13.3 versus 3.98 for ccRCC). Among kidney recipients, RCC risk was significantly elevated for blacks compared to whites (hazard ratio [HR] 1.50) and lower in females than males (HR 0.56). RCC risk increased with prolonged dialysis preceding transplantation (p-trend < 0.0001). Risk was variably associated for RCC subtypes with some medical conditions that were indications for transplantation: ccRCC risk was reduced with polycystic kidney disease (HR 0.54), and papillary RCC was increased with hypertensive nephrosclerosis (HR 2.02) and vascular diseases (HR 1.86). In conclusion, kidney recipients experience substantially elevated risk of RCC, especially for papillary RCC, and multiple factors contribute to these cancers.

The rationale behind antibiotic resistance pattern in Klebsiella pneumoniae

Presently, there is an increase in antibiotic resistance in bacteria, due to relax prescription of antibiotics, especially in Iran. Undoubtedly, in toxin antitoxin (TA) system, a toxin neutralized by antitoxin, which known as a potent antimicrobial target; but there is no extensive survey on the prevalence of TA loci in large scale of Klebsiella pneumoniae. Therefore, this study aims to determine the prevalence of different TA loci in clinical and environmental K. pneumoniae isolates. For this reason, 48 K. pneumoniae clinical isolates and 49 K. pneumoniae environmental isolates were subjected for evaluation of different TA loci. The results of current study indicated that there is no association between antibiotic resistances and presence of TA loci in clinical and environmental K. pneumoniae. The role of TA loci as a potent target in antibiotic resistant K. pneumoniae has been complicated. Therefore, more studies should be performed to explain why TA loci are presented in K. pneumoniae and what is the rationale behind antibiotic resistant K. pneumoniae?

Analgesic use and risk of renal cell carcinoma: A case-control, cohort and meta-analytic assessment

Analgesics are the most commonly consumed drugs worldwide. Evidence that analgesics increase kidney cancer risk has been mixed. We investigated the association between renal cell carcinoma (RCC) and analgesic use in a large population-based case-control study and a post-trial observational cohort study. Findings were used to update a recent meta-analytic review. We analyzed data from 1,217 RCC cases and 1,235 controls in the US Kidney Cancer Study and 98,807 participants in the US Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial (PLCO: n = 137 RCCs). Self-reported acetaminophen, aspirin and nonsteroid anti-inflammatory drug (NSAID) use and duration information was assessed in relation to RCC. For the US Kidney Cancer Study, we calculated odds ratios (ORs) and 95% confidence intervals (CIs) using unconditional logistic regression. For PLCO, we computed hazard ratios (HRs) and 95%CIs using Cox regression. Among case-control participants, RCC risk was associated with over-the-counter acetaminophen use (OR = 1.35, 95%CI = 1.01-1.83). There was a positive trend with increasing duration (p-trend = 0.01), with a two-fold risk for use ≥10 years (OR = 2.01, 95%CI = 1.30-3.12). No association with prescription acetaminophen use was detected. In PLCO, acetaminophen use was also associated with increased RCC risk (HR = 1.68, 95%CI = 1.19-2.39), although elevated risk was absent among the few long-term users. No association with RCC risk was detected for aspirin or NSAIDs use in either study. An association between acetaminophen use and kidney cancer was supported by meta-analytic cohort (n = 4; summary relative risk = 1.34; 95%CI = 1.13-1.59; p-heterogeneity  = 0.40) and case-control (n = 9, summary OR = 1.20; 95%CI = 1.01-1.42; p-heterogeneity  = 0.05) findings. In brief, acetaminophen use may increase the risk of developing RCC.

Abstract A1-31: Molecular characteristics and predictors of poor prognosis in sporadic clear cell renal cancer among central/eastern European and United States patients

We investigated patient/tumor characteristics/inherited variants, hypoxia inducible factor 1 and 2 alpha (HIF1A/HIF2A) protein expression, and patient survival among Central European (CE) and United States (US) clear cell renal cancer (ccRCC) patients from two case-control studies. VHL inactivation, HIF1A, and HIF2A expression have been implicated in RCC and angiogenesis. GWAS studies have identified EPAS1 variants encoding the protein HIF2A associated with RCC risk. We conducted a hospital-based case-control study in Central/Eastern Europe (CE) and a population-based study in the US (Detroit, Chicago) that included whites and blacks. We used data on: i) patient/tumor characteristics, ii) inherited tagging single nucleotide polymorphisms (SNPs) in genes involved in the VHL-HIF pathway (HIF1A, EPAS1, VHL), HIF1A and HIF2A protein expression using immunohistochemical (IHC) methods, and survival from 696 CEERCC and 328 US ccRCC cases. ccRCC patients from CE Europe were older, presented at a higher grade, stage, with larger tumors, had lower BMI, less family history and smoked less (all p&lt;0.0001) compared to US cases. US cases demonstrated higher intensity HIF1A and HIF2A protein expression compared to CE cases (p&lt;0.0001). Black US ccRCC cases were more likely to be hypertensive (p&lt;0.0001) and have lower HIF2A protein expression compared to white US cases. HIF1A and HIF2A were examined for associations with patient/tumor characteristics. In the US study, younger patients had higher levels of HIF2A expression compared to older cases and high BMI was associated with HIF1A expression. In both studies, tumor grade, stage and size at diagnosis were associated with lower HIF1A and HIF2A expression. In analyses adjusted for center, race, sex, age, hypertension, BMI, smoking, tumor grade and stage, HIF1A expression was significantly associated with HIF2A expression (P-trend&lt;0.0001). We assessed associations of variants in EPAS1 (N=16), HIF1A (N=11), and VHL (N=9) with HIF1A and HIF2A expression in ccRCC tissue using tissue microarrays. Seven HIF1A SNPs were significantly associated with HIF1A expression and one EPAS1 SNP (rs1374748) with HIF2A expression. Median survival time was longer in CE compared to USRCC cases (100.3 vs. 86.0 months, p=0.001), women than men (97.1 vs 91.0 months, p=0.02) but similar among whites and blacks in the US study (86.0 vs 87.0 months). In Cox proportional hazard models, in both studies combined, risk of death was higher for those with large tumors (&gt;4cm, p&lt;0.0001) and with a higher stage 1 vs 2, 3+4 (p&lt;0.0001, both) In contrast, ccRCC-specific survival was higher among USRCC than CE patients (19.8 vs 38.0 months, p=0.04) but similar among white compared to black US ccRCC patients (37.0 vs 40.0 months, p=0.50).

Citation Format: Lee Moore, Petra Lenz, Meredith Yeager, Ruth Pfeiffer, Ghislaine Scelo, Mark Purdue, David Zaridze, Kendra Schwartz, Neonilia szeszenia-Dabrowska, Faith Davis, Joanne Colt, vladimir Janout, Marie Navritalova, Paolo Boffetta, Laurie Burdette, Sara Karami, Paul Brennan, Jon Hofmann, Michael Nickerson, Wong-Ho Chow, Margaret Tucker, Stephen Chanock, Stephen Hewitt, Jorge Toro, Nat Rothman. Molecular characteristics and predictors of poor prognosis in sporadic clear cell renal cancer among central/eastern European and United States patients. [abstract]. In: Proceedings of the AACR Special Conference on Translation of the Cancer Genome; Feb 7-9, 2015; San Francisco, CA. Philadelphia (PA): AACR; Cancer Res 2015;75(22 Suppl 1):Abstract nr A1-31.

A case-control study of occupational sunlight exposure and renal cancer risk

Epidemiological evidence of a relationship between vitamin D and kidney cancer risk has been inconsistent despite experimental data indicating that vitamin D and its metabolites may inhibit carcinogenesis. Previously we reported an inverse association between renal cell carcinoma (RCC) risk and occupational ultraviolet (UV) exposure among European men. In this study, we examined the association between occupational UV exposure and RCC risk among US residents and investigated whether this association varied by race and sex. Lifetime occupational data for 1,217 RCC cases and 1,235 controls in a population-based case-control study, conducted from 2002 to 2007, were assessed for occupational UV exposure. We evaluated exposure metrics in quartiles based on control exposure levels and calculated associations between RCC risk and occupational UV exposure using unconditional logistic regression adjusted for sex, race, body mass index, smoking, hypertension, center, education, family history of cancer and dietary vitamin D intake. A general pattern of decreasing RCC risk with increasing UV exposure was observed. Cases had significantly lower cumulative occupational UV exposure than controls (fourth quartile vs. first: odds ratio = 0.74 [95% confidence interval = 0.56-0.99], p-trend = 0.03). Similar results were observed for other UV exposure metrics. The association with occupational UV exposure was stronger for women than for men, but did not differ by race. Our findings suggest an inverse association between occupational UV exposure and RCC, particularly among women. Given the sex finding discrepancies in this study versus our previous study, additional research is need to clarify whether the protective effects of occupational UV exposure and RCC risk are real.

Abstract 4609: Risk loci in telomere structure and maintenance genes across five cancer types: GAME-ON Consortium

Telomeres are complex structures that cap chromosome ends, protecting them from degradation, double strand breaks and end-to-end fusions. Telomeres are maintained by the enzyme telomerase, which is made up of a reverse transcriptase encoded by TERT, and an RNA template encoded by TERC. The telomere structure itself is composed of proteins encoded by ACD, ACYP2, BICD1, DKC1, DCLRE1B, MPHOSPH6, NAF1, NOLA1, NOLA2, NOLA3, OBFC1, PIK3C3, POT1, RTEL1, TEP1, TERF1, TERF2, TERF21P, TINF2, TNKS/PINX1, TPP1 and ZNF208. Several single nucleotide polymorphisms (SNPs) in the TERT and adjoining CLPTM1L gene region are associated with multiple cancer types, and some are associated with both increased and decreased risks across different cancer types. We systematically characterized the patterns of association between variants in these 25 telomere structure and maintenance genes and risk across five cancer types in the Genetic Association and Mechanisms in Oncology (GAME-ON) consortium.

We performed a subset-based meta-analysis (ASSET) of 209,367 directly measured and imputed SNPs, one megabase up- and downstream of these genes, across genome-wide association studies of colorectal (5,100 cases, 4,831 controls), lung (12,160 cases, 16,838 controls), breast (15,748 cases, 18,084 controls), ovarian (4,369 cases, 9,123 controls) and prostate (14,160 cases, 12,724 controls) cancers. Correlations (r2) between SNPs were examined in Haploview using the 1000 Genomes Project CEU population.

A total of 87 TERT, 123 TERC and 26 DCLRE1B SNPs were associated with cancer risk at gene-level Bonferroni-corrected p-values of 4.2-7.8×10−6. Patterns of association were similar for prostate and colorectal cancers in DCLRE1B. Much stronger associations were observed in TERT and TERC, with 63 and 24 SNPs reaching genome-wide significance (p&lt;5.0×10−8), respectively. Of these, 9 TERT and 9 TERC SNPs were correlated at r2&lt;0.75. The most strongly associated SNPs in TERT (rs37004, p = 2.6×10−11) and TERC (rs76925190, p = 1.5×10−15) are in regions containing documented risk loci for lung and prostate cancers, respectively. TERT rs37004 (p = 1.2×10−13) and 6 of the other 9 SNPs in TERT were associated only with lung cancer risk. For the other 2 SNPs, there was a suggestion that patterns of risk were opposite for lung and prostate cancers. While TERC rs76925190 was strongly associated with prostate cancer risk (p = 5.4 x10−17), it was also suggestively associated with colorectal cancer risk (p&lt;0.005). This pattern was similar for another 2 of the 9 SNPs, while for the rest, associations were limited to prostate cancer.

The complex patterns of association in telomere structure and maintenance genes observed across cancer types may provide insight about the mechanisms through which telomere dysfunction in different tissues influences cancer risk.

Citation Format: Sara Karami, Younghun Han, Fredrick R. Schumacher, Zsofia Kote-Jarai, Sara Lindstrom, John S. Witte, Iona Cheng, Shenying Fang, Jiali Han, Peter Kraft, Fengju Song, Rayjean J. Hung, James McKay, Stephen J. Chanock, Mala Pande, Angela Risch, Hongbing Shen, Christopher A. Haiman, Lisa Boardman, Cornelia M. Ulrich, Graham Casey, Ulrike Peters, Nilanjan Chatterjee, Brandon Pierce, Wei Zheng, Christopher I. Amos, Jennifer A. Doherty. Risk loci in telomere structure and maintenance genes across five cancer types: GAME-ON Consortium. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 4609. doi:10.1158/1538-7445.AM2015-4609

LINE1 methylation levels in pre-diagnostic leukocyte DNA and future renal cell carcinoma risk

Higher levels of LINE1 methylation in blood DNA have been associated with increased kidney cancer risk using post-diagnostically collected samples; however, this association has never been examined using pre-diagnostic samples. We examined the association between LINE1 %5mC and renal cell carcinoma (RCC) risk using pre-diagnostic blood DNA from the United States-based, Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial (PLCO) (215 cases/436 controls), and the Alpha-tocopherol, Beta-carotene Cancer Prevention Study (ATBC) of Finnish male smokers (191 cases/575 controls). Logistic regression adjusted for age at blood draw, study center, pack-years of smoking, body mass index, hypertension, dietary alcohol intake, family history of cancer, and sex was used to calculate odds ratios (ORs) and 95% confidence intervals (CIs) using cohort and sex-specific methylation categories. In PLCO, higher, although non-significant, RCC risk was observed for participants at or above median methylation level (M2) compared to those below the median (M1) (OR: 1.37, 95% CI: 0.96-1.95). The association was stronger in males (M2 vs. M1, OR: 1.54, 95% CI: 1.00-2.39) and statistically significant among male smokers (M2 vs. M1, OR: 2.60, 95% CI: 1.46-4.63). A significant interaction for smoking was also detected (P-interaction: 0.01). No association was found among females or female smokers. Findings for male smokers were replicated in ATBC (M2 vs. M1, OR: 1.31, 95% CI: 1.07-1.60). In a pooled analysis of PLCO and ATBC male smokers (281 cases/755 controls), the OR among subjects at or above median methylation level (M2) compared to those below the median (M1) was 1.89 (95% CI: 1.34-2.67, P-value: 3 x 10(-4)); a trend was also observed by methylation quartile (P-trend: 0.002). These findings suggest that higher LINE1 methylation levels measured prior to cancer diagnosis may be a biomarker of future RCC risk among male smokers.

A prospective study of alcohol consumption and renal cell carcinoma risk

Recent epidemiological studies suggest that alcohol consumption may reduce renal cell carcinoma (RCC) risk, although inconsistent findings have been reported by sex and alcoholic beverage type. To better understand the relationship between alcohol consumption and RCC risk, we conducted an analysis within the Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial. We followed up participants in the analytic cohort (N = 107,998) through 2010 for incident RCC (N = 408), and computed hazard ratios (HRs) and 95% confidence intervals (CIs) for alcohol intake using Cox regression with adjustment for age, sex, race, study center, hypertension, body mass index, and smoking status. In this study population increasing alcohol consumption was associated with reduced RCC risk compared to non-drinkers (>9.75 g day(-1) : HR, 0.67; 95%CI, 0.50 to 0.89; p trend = 0.002). We observed similar patterns of association for men and women as well as by alcohol beverage type. In analyses stratified by smoking status, the inverse association with consumption was apparent for ever smokers (HR, 0.51; 95%CI, 0.36 to 0.73; p trend<0.0001) but not among never smokers (HR, 1.08; 95%CI, 0.66 to 1.76; P trend = 0.78; p interaction = 0.01). Our study findings offer further support that alcohol consumption is associated with reduced RCC risk, regardless of sex or alcoholic beverage type. The finding of interaction with smoking is novel and requires confirmation.

LINE1 methylation levels associated with increased bladder cancer risk in pre-diagnostic blood DNA among US (PLCO) and European (ATBC) cohort study participants

Global methylation in blood DNA has been associated with bladder cancer risk in case-control studies, but has not been examined prospectively. We examined the association between LINE1 total percent 5-methylcytosine and bladder cancer risk using pre-diagnostic blood DNA from the United States-based, Prostate, Lung, Colorectal, Ovarian Cancer Screening Trial (PLCO) (299 cases/676 controls), and the Alpha-Tocopherol, Beta-Carotene Cancer Prevention (ATBC) cohort of Finnish male smokers (391 cases/778 controls). Logistic regression adjusted for age at blood draw, study center, pack-years of smoking, and sex was used to estimate odd ratios (ORs) and 95% confidence intervals (CIs) using study- and sex-specific methylation quartiles. In PLCO, higher, although non-significant, bladder cancer risks were observed for participants in the highest three quartiles (Q2-Q4) compared with the lowest quartile (Q1) (OR = 1.36, 95% CI: 0.96 -1.92). The association was stronger in males (Q2-Q4 vs. Q1 OR = 1.48, 95% CI: 1.00-2.20) and statistically significant among male smokers (Q2-Q4 vs. Q1 OR = 1.83, 95% CI: 1.14-2.95). No association was found among females or female smokers. Findings for male smokers were validated in ATBC (Q2-Q4 vs. Q1: OR = 2.31, 95% CI: 1.62-3.30) and a highly significant trend was observed (P = 8.7 × 10(-7)). After determining that study data could be combined, pooled analysis of PLCO and ATBC male smokers (580 cases/1119 controls), ORs were significantly higher in Q2-Q4 compared with Q1 (OR = 2.03, 95% CI: 1.52-2.72), and a trend across quartiles was observed (P = 0.0001). These findings suggest that higher global methylation levels prior to diagnosis may increase bladder cancer risk, particularly among male smokers.

Hysterectomy and kidney cancer risk: a meta-analysis

Recent cohort findings suggest that women who underwent a hysterectomy have an elevated relative risk of kidney cancer, although evidence from past studies has been inconsistent. We conducted a systematic review and meta-analysis of published cohort and case-control studies to summarize the epidemiologic evidence investigating hysterectomy and kidney cancer. Studies published from 1950 through 2012 were identified through a search of PubMed and of references from relevant publications. Meta-analyses were conducted using random-effects models to estimate summary relative risks (SRRs) and 95% confidence intervals (CIs) for hysterectomy, age at hysterectomy (<45, 45+ years) and time since hysterectomy (<10, 10+ years). The SRR for hysterectomy and kidney cancer for all published studies (seven cohort, six case-control) was 1.29 (95% CI, 1.16-1.43), with no evidence of between-study heterogeneity or publication bias. The summary effect was slightly weaker, although still significant, for cohorts (SRR, 1.26; 95% CI, 1.11-1.42) compared with case-control findings (1.37; 95% CI, 1.09-1.73) and was observed irrespective of age at hysterectomy, time since the procedure and model adjustment for body mass index, smoking status and hypertension. Women undergoing a hysterectomy have an approximate 30% increased relative risk of subsequent kidney cancer. Additional research is needed to elucidate the biological mechanisms underlying this association.

Pesticide exposure and inherited variants in vitamin d pathway genes in relation to prostate cancer

BACKGROUND

Vitamin D and its metabolites are believed to impede carcinogenesis by stimulating cell differentiation, inhibiting cell proliferation, and inducing apoptosis. Certain pesticides have been shown to deregulate vitamin D's anticarcinogenic properties. We hypothesize that certain pesticides may be linked to prostate cancer via an interaction with vitamin D genetic variants.

METHODS

We evaluated interactions between 41 pesticides and 152 single-nucleotide polymorphisms (SNP) in nine vitamin D pathway genes among 776 prostate cancer cases and 1,444 male controls in a nested case-control study of Caucasian pesticide applicators within the Agricultural Health Study. We assessed Pinteraction values using likelihood ratio tests from unconditional logistic regression and a false discovery rate (FDR) to account for multiple comparisons.

RESULTS

Five significant interactions (P < 0.01) displayed a monotonic increase in prostate cancer risk with individual pesticide use in one genotype and no association in the other. These interactions involved parathion and terbufos use and three vitamin D genes (VDR, RXRB, and GC). The exposure-response pattern among participants with increasing parathion use with the homozygous CC genotype for GC rs7041 compared with unexposed participants was noteworthy [low vs. no exposure: OR, 2.58, 95% confidence interval (CI), 1.07-6.25; high vs. no exposure: OR, 3.09, 95% CI, 1.10-8.68; Pinteraction = 3.8 × 10(-3)].

CONCLUSIONS

In this study, genetic variations in vitamin D pathway genes, particularly GC rs7041, an SNP previously linked to lower circulating vitamin D levels, modified pesticide associations with prostate cancer risk.

IMPACT

Because our study is the first to examine this relationship, additional studies are needed to rule out chance findings.

Use of OMIC technologies to study arsenic exposure in human populations

Exposure to arsenic (As) in drinking water is a major health concern. More than 100 million individuals are exposed to levels over the current World Health Organization standard of 10 µg/L worldwide. Arsenic is one of the few agents established as a human carcinogen prior to understanding its mechanism of carcinogenicity. OMIC technologies have enabled researchers to utilize agnostic approaches to explore new, unknown mechanisms through which As causes disease in exposed human populations. In this article, we present recent studies in which OMIC technologies have been used to explore differences in human biological samples to identify markers of exposure, disease susceptibility, and effect in As-exposed and/or diseased tissues.

Reproductive factors and kidney cancer risk in 2 US cohort studies, 1993-2010

Clinical and experimental findings suggest that female hormonal and reproductive factors could influence kidney cancer development. To evaluate this association, we conducted analyses in 2 large prospective cohorts (the National Institutes of Health-AARP Diet and Health Study (NIH-AARP), 1995-2006, and the Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial (PLCO), 1993-2010). Cohort-specific and aggregated hazard ratios and 95% confidence intervals relating reproductive factors and kidney cancer risk were computed by Cox regression. The analysis included 792 incident kidney cancer cases among 283,952 postmenopausal women. Women who had undergone a hysterectomy were at a significantly elevated kidney cancer risk in both NIH-AARP (hazard ratio = 1.28, 95% confidence interval: 1.09, 1.50) and PLCO (hazard ratio = 1.41, 95% confidence interval: 1.06, 1.88). Similar results were observed for both cohorts after analyses were restricted to women who had undergone a hysterectomy with or without an oophorectomy. For the NIH-AARP cohort, an inverse association was observed with increasing age at menarche (P for trend = 0.02) and increasing years of oral contraceptive use (P for trend = 0.02). No clear evidence of an association with parity or other reproductive factors was found. Our results suggest that hysterectomy is associated with increased risk of kidney cancer. The observed associations with age at menarche and oral contraceptive use warrant further investigation.

Abstract 686: LINE-1 %5-Methylcytosine levels in pre-diagnostic leukocyte DNA and subsequent renal cell cancer risk

Background: Alteration of DNA methylation is thought to promote carcinogenesis by weakening chromosomal stability and changing normal gene expression patterns. These epigenetic alterations that occur throughout the genome are considered early events in the carcinogenic process. Lately, long interspersed nucleotide element (LINE-1) methylation levels in blood DNA have been examined in relation to risk of several cancers. One previous renal cell cancer (RCC) case-control study reported higher LINE-1 methylation levels in blood DNA for cases than controls. Since DNA samples from that study were collected post-diagnostically, it remains unclear if the observed difference occurred prior to, or as a result of carcinogenesis. Thus, we examined the association between global methylation and RCC risk using prospectively collected blood samples.

Methods: A nested RCC case-control study was conducted amid subjects in the Alpha-Tocopherol, Beta-Carotene Cancer Prevention (ATBC) cohort, a study of Finnish male Caucasian smokers, 50 to 69 years old. LINE-1 percent 5-methylcytosine (LINE-1 %5-MeC) levels from 191 cases and 575 controls, matched on age at randomization (+/-5 years), were quantified using bisulfite treated blood DNA and pyrosequencing. Cancer risk was assessed in quartiles (Q1:&lt;78.0, Q2:78.0-78.5, Q3:78.6-79.5, Q4:&gt;79.5) of methylation based on control levels. Unconditional logistic regression was used to compute odds ratios (ORs) and 95% confidence intervals (CIs) adjusting for pack-years of smoking, age at randomization, hypertension, family history of cancer, body mass index (BMI) and intervention group.

Results: RCC risk was significantly increased with increasing LINE-1 %5-MeC levels (Q1REF. vs. Q2OR= 1.12 (0.63-1.92), Q3OR= 1.78 (1.06-3.00), Q4OR= 1.78 (1.00-3.03); p-trend= 0.01). Associations appeared more pronounced for males with a higher BMI: (BMI &lt;25kg/m2: Q1 vs. Q2-Q4OR= 0.89 (0.35-2.23); BMI 25-&lt;30kg/m2: Q1 vs. Q2-Q4OR= 1.21 (0.67-2.17); BMI ≥30kg/m2: Q1 vs. Q2-Q4OR= 8.86 (2.20-35.68); p-interaction= 0.01). Decreasing LINE-1 %5-MeC levels were observed with increasing BMI for controls (p-trend= 0.004) but not cases (p-trend=0.19). Analyses for pack-years of smoking showed no association with LINE-1 %5-MeC levels in cases or controls; pack-years of smoking was not shown to modify associations.

Conclusion: Our study findings that increasing LINE-1 %5-MeC levels were associated with higher RCC risk using pre-diagnostically collected blood DNA are consistent with results reported in a previous case-control study. Yet, stratified results for BMI and smoking observed post-diagnostically in that case-control study are not supported in pre-diagnostic samples used here. Our results suggest that higher methylation levels are reflective of elevated RCC risk prior to diagnosis. Additional studies are being conducted in a second cohort to replicate these findings.

Citation Format: Sara Karami, Gabriella Andreotti, Ruth M. Pfeiffer, Linda M. Liao, Stephanie Weinstein, Demetrius Albanes, Jarmo Virtamo, Nathaniel Rothman, Lee E. Moore. LINE-1 %5-Methylcytosine levels in pre-diagnostic leukocyte DNA and subsequent renal cell cancer risk . [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 686. doi:10.1158/1538-7445.AM2013-686

The association between chronic renal failure and renal cell carcinoma may differ between black and white Americans

PURPOSE

In the United States, renal cell carcinoma (RCC) incidence is higher among blacks than among whites. Risk of RCC is elevated among end-stage renal disease patients, although no studies have looked at differences by race in the relationship between chronic renal failure and RCC.

METHODS

We investigated RCC risk in relation to chronic renal failure in a population-based case-control study of blacks and whites in Chicago and Detroit. Data, including information on kidney disease, were collected from interviews with 1,217 RCC cases (361 blacks, 856 whites) and 1,235 controls (523 blacks, 712 whites). Odds ratios (OR) and 95 % confidence intervals (CI) were estimated using unconditional logistic regression.

RESULTS

Risk of RCC was increased in relation to chronic renal failure (OR 4.7, 95 % CI 2.2-10.1) and dialysis (OR 18.0, 95 % CI 3.6-91). The association remained after defining exposure as those who had chronic renal failure ≥10 years prior to RCC diagnosis. Chronic renal failure was more strongly associated with RCC among blacks than among whites (OR 8.7, 95 % CI 3.3-22.9 and 2.0, 0.7-5.6, respectively; p (interaction) = 0.03) and among those without a history of diabetes relative to diabetic subjects (OR 8.3, 95 % CI 3.1-22.7 and 1.9, 0.6-5.9, respectively; p (interaction) = 0.03).

CONCLUSIONS

These results suggest that chronic renal failure is a strong risk factor for RCC, particularly among black and non-diabetic subjects. Our findings of differences in risk estimates by race, to our knowledge the first such report, require replication.

Abstract PR1: LINE-1 %5-methyl cytosine levels in prediagnostic leukocyte DNA and future bladder cancer risk among PLCO and ATBC cohort subjects

Background: Low global methylation levels measured in post-diagnostic case compared to healthy control blood DNA have been associated with elevated bladder cancer risk.

Objective: To examine this association using blood DNA collected prior to bladder cancer diagnosis.

Methods: Cases (n=437) and controls (N=847) were selected from the Prostate, Lung, Colorectal, Ovarian Cancer Screening Trial (PLCO). A replication case-control study was conducted among males from the Alpha-Tocopherol, Beta-Carotene Cancer Prevention (ATBC) cohort (391 cases/778 controls). LINE-1 percent 5-methyl-cytosine (LINE-1 %5-MeC) levels were quantified using bisulfite treated blood DNA and pyrosequencing. Cancer risk was assessed in deciles (D1-D10: 10-100%) and quartiles (Q1-Q4:25-100%) of methylation levels based on controls. Logistic regression was used to evaluate individual and pooled study data.

Findings: In PLCO, significantly lower bladder cancer risk was associated with the lowest LINE-1 %5-MeC decile (D1) compared to D2-D10 subjects adjusted for sex and pack-years of smoking (OR=0.35; 95% CI: 0.18-0.68, p=0.002). Findings were corroborated in the ATBC study, (D1 vs. D2-D10: OR=0.31;95% CI:0.17-0.57, p&lt;0.001) adjusting for pack-years of smoking and intervention assignment. When male data were pooled, a similar association was observed comparing D1 to D2-D10 subjects (OR=0.35;95% CI:0.21-0.57, p&lt;0.001) and by quartiles (OR Q1=0.53;95% CI:0.41-0.70, p&lt;0.001). Smoking status did not modify the associations.

Interpretation: Findings observed in two independent studies using pre-diagnostically collected bladder cancer case/control subject DNA support that higher methylation levels may reflect higher bladder cancer risk prior to diagnosis. Associations using pre-diagnostically collected blood DNA were opposite to those from previous case-control studies using post-diagnostic DNA, suggesting changes in methylation levels associated with the carcinogenic process. Additional prospective studies evaluating LINE1 and gene-specific CpG methylation levels are needed to replicate and extend these findings.

This proffered talk is also presented as Poster 11.

Citation Format: Gabriella Andreotti, Sara Karami, Ruth Pfeiffer, Lauren Hurwitz, Linda Liao, Stephanie Weinstein, Demetrius Albanes, Jarmo Virtamo, Debra Silverman, Nathaniel Rothman, Lee Moore. LINE-1 %5-methyl cytosine levels in prediagnostic leukocyte DNA and future bladder cancer risk among PLCO and ATBC cohort subjects. [abstract]. In: Proceedings of the AACR Special Conference on Post-GWAS Horizons in Molecular Epidemiology: Digging Deeper into the Environment; 2012 Nov 11-14; Hollywood, FL. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2012;21(11 Suppl):Abstract nr PR1.

A case-control study of occupation/industry and renal cell carcinoma risk

Background

The role of occupation in the etiology of renal cell carcinoma (RCC) is unclear. Here, we investigated associations between employment in specific occupations and industries and RCC, and its most common histologic subtype, clear cell RCC (ccRCC).

Methods

Between 2002 and 2007, a population-based case–control study of Caucasians and African Americans (1,217 cases; 1,235 controls) was conducted within the Detroit and Chicago metropolitan areas to investigate risk factors for RCC. As part of this study, occupational histories were ascertained through in-person interviews. We computed odds ratios (ORs) and 95% confidence intervals (CIs) relating occupation and industry to RCC risk using adjusted unconditional logistic regression models.

Results

Employment in the agricultural crop production industry for five years or more was associated with RCC (OR = 3.3 [95% CI = 1.0-11.5]) and ccRCC in particular (OR = 6.3 [95% CI = 1.7-23.3], P for trend with duration of employment = 0.0050). Similarly, RCC risk was elevated for employment of five years or longer in non-managerial agricultural and related occupations (OR_RCC = 2.1 [95% CI = 1.0-4.5]; OR_ccRCC = 3.1 [95% CI = 1.4-6.8]). Employment in the dry-cleaning industry was also associated with elevated risk (OR_RCC = 2.0 [95% CI = 0.9-4.4], P for trend = 0.093; OR_ccRCC = 3.0 [95% CI = 1.2-7.4], P for trend = 0.031). Suggestive elevated associations were observed for police/public safety workers, health care workers and technicians, and employment in the electronics, auto repair, and cleaning/janitorial services industries; protective associations were suggested for many white-collar jobs including computer science and administrative occupations as well employment in the business, legislative, and education industries.

Conclusions

Our findings provide support for an elevated risk of RCC in the agricultural and dry-cleaning industries and suggest that these associations may be stronger for the ccRCC subtype. Additional studies are needed to confirm these findings.

Evaluation of metal pollution in fish and water collected from Gorgan coast of the Caspian Sea, Iran

In this study, concentrations of zinc, chromium, cadmium and lead were determined in water and three species of fish sampled from 10 selected stations along Gorgan coast using atomic absorption spectrophotometery, summer 2009. Mean lead levels in water and fish samples (119.50 ± 22.24 μg/L and 113.80 ± 33.11 μg/kg) were significantly higher than that of cadmium and chromium (p < 0.05). Cyprinus carpio had highest metals content than Mugila auratus and Rutilus frisikutum. The evaluated metals values in water collected from Gomishan wetland (Pb, Cd, Cr and Zn values are 145.31 ± 35.32, 120.46 ± 11.44, 96.47 ± 6.05 and 82.02 ± 34.37 μg/L, respectively) were higher than the other sampling sites. The result is consistent with the findings accessed by evaluation of the metals in fish specimens. The metals concentrations in the fish and water samples were below the recommended limits. But, elevating levels of metals in water and fish made a serious concern about ecosystem and food chain contamination.