Citations

Abstract Objective. Molecularly distinct PCNSL signatures with divergent clinical behavior are now recognized. Implied within this heterogeneity are mechanisms for treatment response and pattern of failure. Recent cytogenetic and genomic studies demonstrated influences of select chromosomal regions on outcome to treatment and survival. These included genetic and epigenetic alterations affecting CDKN2A (9p21.3) that distinguished PCNSL from its systemic counterpart. We now report that deletion of 9p21.3/p16 is associated with a negative effect on survival. Methods and Patients. Well-annotated and population-based formalin fixed paraffin embedded (FFPE) patient samples were sourced from the SEER TRP. Specimens were retrieved from the Hawaii, Iowa and Los Angeles County (LA Co) tissue repositories. “Home Brew” fluorescent in situ hybridization (FISH) probes for BCL6, and ptpr-α were prepared according to a standard protocol (Cady et al. J Clin Oncol 2008;26:4814-9). FISH probes for 9p.21 were prepared similarly and then compared to a commercially available probe. Survival was based on the SEER TRP clinical annotations. Results. Thirty five patients were sourced - twelve from Iowa, 13 from Hawaii, and 10 from LA County. The test cohort was 23 from Iowa and Hawaii; the FISH probe failed in 9 and three had insufficient remaining tumor for analysis. For the Iowa and Hawaii registries and for the registries combined the lack of FISH probe detection of 9p.21/p16 correlated with survival (p=0.0159) and was independent of BCL6 (p=0.8788) and ptpr-α (p=0.3724). Conclusion. Deletion of p16 confers a negative effect on survival of PCNSL patients and appears to be independent of treatment, age, BCL6 and ptpr-α status. These results need to be confirmed in a larger sample size. 9p21.3 detection by FISH in feasible in surgical specimens and may aid in the stratification of such patients into different and/or more intensive treatment regimens. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 4507. doi:1538-7445.AM2012-4507

Abstract Background: Despite recent advances in prevention and therapy, colorectal cancer (CRC) continues to account for nearly 50,000 deaths per year in the US. TNM stage is the current CRC prognostic standard, yet within-stage prognostic heterogeneity is well documented. Microsatellite instability (MSI), CpG island methylation phenotype (CIMP), and BRAF- and KRAS-mutation status represent candidate prognostic markers. However, associations between these markers and CRC survival have not been described in a population-based setting. Methods: Data and tissue resources were obtained from the Iowa Women's Health Study (IWHS), which recruited 41,836 women, ages 55-69 years, at study entry (1986). Incident CRC cases were ascertained by annual linkage with the Iowa Cancer Registry. Archived, paraffin-embedded tissue specimens were collected from 732 representative CRC cases diagnosed through 12/31/2002. Established laboratory methods were used to characterize CRC cases: MSI-H or MSS/MSI-L (by instability in β3 vs. <3 out of 10 markers, respectively); CIMP+ or CIMP− (by promoter hypermethylation in β3 vs. 0-2 out of 5 genes, respectively); BRAFwt or BRAFmut (by fluorescent allele specific PCR to detect the V600E point mutation in exon 15); and KRASwt or KRASmut (by direct sequence analysis of codons 12 and 13 in exon 2). Cox regression models were fit to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for time to death of any cause adjusted for age, stage, grade, and treatment status. Results: CRC cases with informative molecular marker data ranged from 515/732 (70%) for KRAS to 548/732 (75%) for MSI status. Mean follow-up was 4.4 years for deceased individuals and 11.2 years for women alive at last contact. After multivariable adjustment, both MSS/MSI-L (p=0.004) and KRASmut (p=0.048) tumors were associated with poorer survival. Survival did not significantly differ across levels of CIMP and BRAF status. Conclusions: MSI and KRAS status may influence CRC survival among older women. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 4492. doi:1538-7445.AM2012-4492

Abstract Some studies show that childbearing at older age is associated with lower risk of endometrial cancer, but whether the association is independent of number of children or other factors still requires clarification. We pooled individual-level data from epidemiologic studies in the Epidemiology of Endometrial Cancer Consortium (E2C2). Data on age at last birth and/or last pregnancy were available from 14 studies: 11 case-control studies and 3 cohort studies; the latter were analyzed using a nested case-control design. A total of 9,613 endometrial cancer cases and 17,112 controls were included in the analysis. The majority of women were White (82%) and older than 55 years (69%). We estimated the effects of age at last birth using data from 12 studies and age at last pregnancy using data from 10 studies on the risk of endometrial cancer by calculating odds ratios (OR) and 95% confidence intervals (95% CI) using logistic regression models. Potential confounders included in the analysis were race, body mass index, parity, age at menarche, age at first birth, oral contraceptive use, postmenopausal hormone use, smoking status, and report of diabetes. After adjusting for potential confounders, a reduction in endometrial cancer risk was observed in women with increasing age at last birth (P trend <0.0001) and age at last pregnancy (P trend <0.0001). The OR per five-year increase in age at last birth and age at last pregnancy was 0.90 (95%CI: 0.86, 0.94) and 0.91 (95% CI: 0.87, 0.95), respectively. Women who had their last child at an age >40 years were at a 34% decreased risk compared with women who had their last child at an age <25 years (95% CI: 0.52, 0.82). Compared to women with age at last pregnancy <25 years, those with age at last pregnancy >40 years had a 30% decreased risk of endometrial cancer (95%CI: 0.57, 0.86). Inverse associations were observed for Whites and Asians in race-specific analysis and also in analysis restricted to women with at least 2 births. In this large pooled analysis, we show that late age at last birth or last pregnancy is a strong and independent protective factor for endometrial cancer. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 1900. doi:10.1158/1538-7445.AM2011-1900

Abstract Background. Several recent studies have reported an inverse relationship between sun exposure and non-Hodgkin (NHL) risk. One hypothesis is that vitamin D mediates this effect. We evaluated the association of sun exposure at various ages and common variants in vitamin D related genes with risk of NHL and its major subtypes. Methods. Newly diagnosed NHL cases (N=1023) and frequency matched controls (N=1254) were enrolled in a clinic-based case-control study conducted at the Mayo Clinic. Thirty-eight single nucleotide polymorphisms (SNPs) from 5 candidate genes relevant to vitamin D metabolism and sun sensitivity (IRF4, RXR, VDR, CYP24A1, CYP27B1) were genotyped. Participants also completed a detailed questionnaire, including self-reported sun exposure at ages 13-21, 22-40, and 41+ years. Odds ratios (OR), 95% confidence intervals (CI), and tests for trend and effect modification were estimated using unconditional logistic regression adjusted for age and gender. ORs are reported for the highest vs. lowest exposure category or as the ordinal OR for SNPs. Results. The mean age of diagnosis/enrollment was 61 years for cases and 60 years for controls. The most common subtypes were chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL; 34%), follicular (FL; 24%), and diffuse large B-cell (DLBCL; 18%) lymphomas. There was a significant decrease in NHL risk with increased sun exposure at ages 13-21 years (OR=0.66, 95% CI 0.44-1.00; ptrend=0.04), which attenuated with increasing age at exposure. Exploratory analysis by NHL subtype indicated a trend toward a protective effect of sun exposure at ages 13-21 years for each of the major subtypes, though these estimates did not reach statistical significance. Of the 38 SNPs evaluated, there was a significant association for 3 SNPs in VDR and 1 SNP in CYP24A1: rs3819545 (OR=1.24, 95% CI 1.10-1.40, p=0.0004), rs2239186 (OR=1.22, 95% CI 1.05-1.41, p=0.009), and rs886441 (OR=0.82, 95% CI 0.70-0.96, p=0.02) for VDR and rs2762939 (OR=0.85, 95% CI 0.75-0.98, p=0.02) for CYP24A1. Both the VDR and CYP24A1 associations were observed for CLL/SLL, FL, but were attenuated for DLBCL. There was no evidence of any significant effect modification of sun exposure at ages 13-21 years by genotype in these four SNPs for NHL overall, or for NHL subtypes. Conclusions. We observed an inverse association between the frequency of sun exposure at ages 13-21 years and NHL risk, which attenuated for sun exposure at older ages, suggesting that early life exposure may be more relevant. While genetic variation in VDR and CYP24A1 were associated with NHL risk, there was no evidence for an interaction of sun exposure with these genes, suggesting that a sun association may not act through the vitamin D metabolism pathway. This would be consistent with a lack of association of circulating vitamin D with NHL risk recently published from the Cohort Consortium pooling project. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 1894. doi:10.1158/1538-7445.AM2011-1894

Abstract Background: Folate intake (FI) appears to affect colorectal cancer (CRC) risk, but the molecular mechanism(s) involved are incompletely defined. In this study, we analyzed associations between FI and incident CRC, overall and by KRAS mutation status, in the population-based Iowa Women's Health Study (IWHS). Methods: The IWHS recruited 41,836 randomly selected Iowa women, ages 55-69 years, with a valid driver's license at study entry (1986). FI and other exposure variables were assessed at baseline, by self-report. Incident CRC cases were ascertained by annual linkage with the Iowa Cancer Registry. Archived, paraffin-embedded tissue specimens were recently collected from 732 representative CRC cases diagnosed through 12/31/2002. FI (including supplements) was categorized by quartiles. KRAS mutation status (wildtype [wt] vs. mutated [mut]) was determined by direct sequence analysis of codons 12 and 13 (exon 2). Multivariate Cox regression models were fit to estimate relative risks (RRs) and 95% confidence intervals (CIs). Results: Of the 732 available CRC cases, 470 (64%) had complete FI and KRAS data. FI was not associated with incident CRC overall (for quartile 4 vs. quartile 1, RR = 1.03; 95% CI = 0.82-1.28; p trend = 0.90), or with the KRAS-wt or KRAS-mut subtypes (see Table). Conclusions: These data do not support an association between FI and incident CRC, overall or by KRAS-defined subtypes, among older, predominately white, non-Hispanic women. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 1892. doi:10.1158/1538-7445.AM2011-1892

Abstract Background: Cigarette smoking (CS) is an established, although relatively modest, colorectal cancer (CRC) risk factor. Emerging data suggest that CS might affect distinct pathways of colorectal carcinogenesis. In this study, we examined CS-associated CRC risks by KRAS mutation status in the population-based Iowa Women's Health Study (IWHS). Methods: The IIWHS recruited 41,836 randomly selected Iowa women, ages 55-69 years, with a valid driver's license at study entry (1986). CS and other exposure variables were assessed at baseline, by self-report. Incident CRC cases were ascertained by annual linkage with the Iowa Cancer Registry. Archived, paraffin-embedded tissue specimens were collected from 732 representative CRC cases diagnosed through 12/31/2002. CS was categorized by smoking status (current, former), average number of cigarettes per day (1-19, 20-39, > 40) and pack-years (1-19, 20-39, > 40); never smokers were defined as the reference group. KRAS mutation status (wildtype [wt] vs. mutated [mut]) was determined by direct sequence analysis of codons 12 and 13 (exon 2). Multivariate Cox regression models were fit to estimate relative risks (RRs) and 95% confidence intervals (CIs). Results: Of the 732 available CRC cases, 507 (69%) had complete CS and KRAS data. Each of the CS-related variables was more strongly associated with KRAS-wt vs. KRAS-mut tumors (see Table). However, event rates were relatively small in some cells, and tests for heterogeneity between KRAS-defined subtypes were not statistically significant (p > 0.05 for each comparison). Conclusions: These findings suggest that CS may affect colorectal carcinogenesis through KRAS-independent pathways, but additional data are needed from larger, more diverse study populations. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 1891. doi:10.1158/1538-7445.AM2011-1891

Abstract Background: NHL is a malignancy of lymphocytes, and there is growing evidence for a role of immune dysfunction in the etiology of this malignancy. We conducted a 2-stage analysis of single nucleotide polymorphisms (SNPs) from 1,253 genes using the ParAllele (now Affymetrix) Immune and Inflammation Panel with risk of NHL. Methods: In Stage 1, we successfully genotyped 7,670 SNPs in a clinic-based study of 425 NHL cases and 465 frequency matched controls seen at the Mayo Clinic. Genes were tagged with SNPs from HapMap to provide coverage at r2 = 0.8 and minor allele frequency (MAF) >0.05. In Stage 2, we genotyped the top 768 SNPs on an additional 584 cases and 768 controls from the Mayo Clinic Study, and then conducted a pooled analysis of all 1009 cases and 1233 controls. The association of individual SNPs with NHL risk was assessed using the Odds Ratios (ORs) and 95% confidence intervals, adjusted for age and gender. The most prevalent homozygous genotype was used as the reference group, and each SNP was modeled individually as having a log-additive effect. Results: Overall, the mean age at diagnosis was 62.0 years for cases and the mean age at enrollment for controls was 61.1 years. The most common subtypes were chronic lymphocytic leukemia (CLL, N=343), follicular lymphoma (FL, N=245), and diffuse large B-cell lymphoma (DLBCL, N=178). In the pooled analysis, there were 3 SNPs at p<0.0004. The top SNP was rs241447 (MAF=0.26) from TAP2 at 6p21.3 (OR=1.34, 95% CI 1.17-1.53, p=0.00003). This SNP is a cSNP that leads to a missense change (Ala→Thr). The second SNP was rs2857597 (MAF=0.26) from AIF1, also at 6p21.3 (OR=0.77, 95% CI 0.67-0.88, p=0.0002). The region spanning these two SNPs had multiple risk SNPs with p<0.01, including SNPs in BAT2 (rs3132453), BAT3 (rs2242656), C2 (rs7746553), HLA-DRA (rs8084, rs7192), and TAP2 (rs1894408). Of these SNPs, only rs241447 (TAP2) and rs7192 (HLA-DRA) displayed any substantial LD (r2=0.84, all other r2<0.25). The third SNP was rs754505 (MAF=0.07) from NFATC1 at 18q23 (OR=0.63, 95% CI 0.49-0.81, p=0.0003). There were 4 additional SNPs in this gene with a p<0.05 (rs7240932, rs396127, rs177820, rs183374). In subtype analysis, the SNPs from 6p21.3 showed the strongest associations with FL (including the TAP2 SNP rs241447, p=6.9 × 10−8), although there were also associations with CLL (except for the TAP2 and C2 SNPs) and DLBCL (except for the HLA-DRA SNPs). For NFATC1 the associations were similar across the main NHL subtypes. Conclusions: We identified strong associations with NHL risk in the 6p21.3 region, which includes the MHC locus. Our results were particularly striking for FL and supports recent GWAS and candidate gene studies that implicate this region. We also identified NFATC1 as a susceptibility gene. NFATC1 is known to regulate the expression of growth and survival genes including MYC, TNF, CD40L, and BAFF, all of which have also been linked to lymphomagenesis. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 2761. doi:10.1158/1538-7445.AM2011-2761

Abstract Background: Ingested nitrate can form N-nitroso compounds endogenously, which may lead to DNA adducts and activating mutations in oncogenes. However, previous studies have reported null or inverse associations between dietary nitrate intake and cancer risk, while nitrate intake from drinking water has shown null or positive associations with cancer risk. These associations may be confounded by protective effects of dietary folate, which provides methyl groups for nucleotide synthesis, and thus plays a vital role in the DNA repair system. In a small case-control study, an increased risk of breast cancer was observed among individuals with high dietary nitrate relative to folate intake. We therefore evaluated interaction of total folate with nitrate intake from diet and drinking water on breast cancer risk in the Iowa Women's Health Study (IWHS). Methods: The IWHS is a prospective cohort study of cancer among 41,836 women in Iowa, initiated in 1986. Dietary intake was assessed at study baseline using a food frequency questionnaire (FFQ). Nitrate intake from foods and total folate intake from foods and dietary supplements were computed using consumption frequencies collected by the FFQ. Nitrate intake from drinking water was assessed using a historical analytical database on Iowa municipal water supplies in 15,151 women using municipal water supply. We evaluated the interaction of nitrate and total folate intake with breast cancer risk using Cox proportional hazard regression modeling, adjusting for potential confounders (age, body mass index, waist-hip-ratio, education, smoking, family history of breast cancer, age at menopause, age at first live birth, estrogen use, total energy intake, and intake of vitamin C and E and flavonoids). Results: After baseline exclusions (history of cancer at baseline, previous mastectomy or partial breast resection, implausible energy intake, or ≥30 missing responses on the FFQ), there were 34,388 postmenopausal women in the analytic cohort. Through 2008, 2,875 incident breast cancer cases were identified. Nitrate intake from diet or drinking water was not associated with breast cancer risk. After stratification by total folate intake, high dietary nitrate intake (>106.1 mg/day) was associated with a marginally decreased risk of breast cancer compared to those with low nitrate intake (≤106.1 mg/day) (HR=0.90, 95% confidence interval=0.81–1.00) only among women with folate intake <400 μg/day (p for interaction = 0.65). There was no interaction of nitrate intake from drinking water and total folate intake on breast cancer risk. Conclusions: Our findings do not support the previously reported increased risk of breast cancer risk among individuals with high dietary nitrate and low folate intake. The inverse association between nitrate intake and breast cancer risk observed among women with low folate intake in the present study may be attributed to residual confounding due to high correlation among intakes of nitrate, folate and antioxidants. Citation Information: Cancer Prev Res 2011;4(10 Suppl):A86.

Abstract We performed a meta-analysis of 3 genome-wide association studies to identify additional common variants influencing chronic lymphocytic leukemia (CLL) risk. The discovery phase was composed of genome-wide association study data from 1121 cases and 3745 controls. Replication analysis was performed in 861 cases and 2033 controls. We identified a novel CLL risk locus at 6p21.33 (rs210142; intronic to the BAK1 gene, BCL2 antagonist killer 1; P = 9.47 × 10−16). A strong relationship between risk genotype and reduced BAK1 expression was shown in lymphoblastoid cell lines. This finding provides additional support for polygenic inheritance to CLL and provides further insight into the biologic basis of disease development.

Abstract Background: Colorectal cancer (CRC) is the third most common incident cancer among women in the United States. Alcohol use has been proposed as a CRC risk factor, but existing observational data remain inconsistent. To date, relatively few studies have examined associations between alcohol use and CRC risk based on molecularly-defined subtypes. Aim: To evaluate associations between alcohol use and incident CRC overall, as well as by molecularly-defined subtypes including microsatellite instability (MSI), CpG island methylator phenotype (CIMP) and BRAF mutation status in the prospective, population-based, Iowa Women's Health Study (IWHS). Methods: The IWHS recruited 41,836 randomly selected Iowa women, ages 55–69 years at enrollment, in 1986. Women with prevalent cancers or no follow-up were excluded, leaving 38,001 eligible for this study. Alcohol use was obtained from a self-administered food frequency questionnaire at study baseline. Incident CRCs were identified through annual linkage with the State Health Registry of Iowa. Archived, paraffin-embedded tissue specimens were recently requested for incident CRC cases diagnosed through December 31, 2002. In the present study, useable tissue specimens were obtained and molecularly characterized for 563/1,255 cases (45%), whose baseline age, body mass index, physical activity level, total energy intake and alcohol use were similar to non-retrieved cases (p > 0.05 for each comparison). Alcohol use was categorized as never (n=21,464), < 3.4 g/day (n=8,313) and > 3.4 g/day (n=8,224), based on the median split among users. Molecularly-defined CRC subtypes were categorized as MSI-high (MSIH; n=148), MSI-low or microsatellite stable (MSI-L/MSS; n=400); CIMP-positive (n=167) or CIMP-negative (n=368); and BRAF-mutation (n=154) or BRAF-wildtype (n=391). Relative risks (RRs) and 95% confidence intervals (95% CIs) were estimated for alcohol use compared to never drinkers, using multivariable Cox regression models adjusted for body mass index, waist-to-hip ratio, smoking status, physical activity level, exogenous estrogen use, and daily intakes of total energy, total fat, red meat, sucrose, calcium, folate, methionine and vitamin E. Results: There was no statistically significant association between alcohol use and overall CRC risk (RR=1.00; 95% CI = 0.86–1.15 for < 3.4 g/day versus none; RR=1.06; 95% CI=0.91–1.24 for >3.4 g/day versus none). Further, there were no associations with alcohol use for specific, molecularly-defined CRC subtypes (RRs shown for > 3.4 g/day versus none): MSI-H (RR=1.07; 95% CI=0.70–1.64); MSI-L or MSS (RR=1.12; 95% CI=0.85–1.47); CIMP-positive (RR=0.97; 95% CI=0.64–1.47); CIMP-negative (RR=1.13; 95% CI=0.85–1.50); BRAF-mutation (RR=0.94; 95% CI=0.61–1.45); and BRAF-wildtype (RR=1.20; 95% CI=0.91–1.57). Conclusion: In this cohort of older women, alcohol use did not appear to be a risk factor for incident CRC, overall or by the defined molecular subtypes. Citation Information: Cancer Prev Res 2010;3(1 Suppl):A115.