Cerhan, James R.

AbstractGenetic aberrations, including trisomies 3 and 18, and well-defined IGH translocations, have been described in marginal zone lymphomas (MZLs); however, these known genetic events are present in only a subset of cases. Here, we report the cloning of an IGH translocation partner on chromosome X, t(X;14)(p11.4;q32) that deregulates expression of an poorly characterized orphan G-protein–coupled receptor, GPR34. Elevated GPR34 gene expression was detected independent of the translocation in multiple subtypes of non-Hodgkin lymphoma and distinguished a unique molecular subtype of MZL. Increased expression of GPR34 was also detected in tissue from brain tumors and surface expression of GPR34 was detected on human MZL tumor cells and normal immune cells. Overexpression of GPR34 in lymphoma and HeLa cells resulted in phosphorylation of ERK, PKC, and CREB; induced CRE, AP1, and NF-κB–mediated gene transcription; and increased cell proliferation. In summary, these results are the first to identify a role for a GPR34 in lymphoma cell growth, provide insight into GPR34-mediated signaling, identify a genetically unique subset of MZLs that express high levels of GPR34, and suggest that MEK inhibitors may be useful for treatment of GPR34-expressing tumors.

PurposeThe optimal management of stage I follicular lymphoma, according to consensus guidelines, is based on uncontrolled experiences of select institutions. Diverse treatment approaches are used despite guidelines that recommend radiation therapy (XRT).Patients and MethodsWe analyzed outcomes of patients with stage I follicular lymphoma enrolled onto the National LymphoCare database.ResultsOf 471 patients with stage I follicular lymphoma, 206 patients underwent rigorous staging as defined by both a bone marrow aspirate and biopsy and an imaging study (a computed tomography [CT] scan of the whole body, a positron emission tomography [PET]/CT scan, or both). Rigorously staged patients had superior progression-free survival (PFS) compared with nonrigorously staged patients (hazard ratio [HR], 0.63). Treatments given to rigorously staged patients were rituximab/chemotherapy (R-chemo; 28%), XRT (27%), observation (17%), systemic therapy + XRT (13%), rituximab monotherapy (12%), and other (3%). With a median follow-up of 57 months for PFS, there were 44 progression events (in 21% of patients) for rigorously staged patients. For these patients, PFS was significantly improved with either R-chemo or systemic therapy + XRT compared with patients receiving XRT alone after adjustment for histology, LDH, and the presence of B symptoms. There were no differences in overall survival.ConclusionIn this largest, prospectively enrolled group of patients with stage I follicular lymphoma, variable treatment approaches resulted in similar excellent outcomes, which challenges the paradigm that XRT should be standard for this presentation.

Abstract Background: Cigarette smoking (CS) is an established colorectal cancer (CRC) risk factor. The p53 protein, encoded by the TP53 tumor suppressor gene that is commonly mutated in CRC, is important in cell cycle arrest needed to repair DNA damage or induce apoptosis to prevent tumor propagation. In this prospective cohort study, we examined CS-associated CRC risks by p53 protein expression level 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). 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 CRC cases diagnosed through 12/31/2002. CS was categorized by smoking status (never, current, former), average number of cigarettes per day (1-19, 20-39, > 40) and cumulative pack-years (1-19, 20-39, > 40). P53 protein expression was determined by immunohistochemistry on tissue microarrays. Tumor cores were scored by combining both staining intensity and percent of cells stained to determine negative, low or high p53 protein expression levels. Multivariate Cox regression models were fit to estimate relative risks (RRs) and 95% confidence intervals (CIs). Results: Of the 732 available CRC cases, 486 (66%) had complete CS and p53 data. Associations between CS and CRC subtypes defined by p53 expression level are shown in the Table. Conclusions: These data demonstrate no clear heterogeneity of CS with CRC subtypes defined by p53 expression levels 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 1677. doi:1538-7445.AM2012-1677

Abstract Background: Cigarette smoking (CS) is an established colorectal cancer (CRC) risk factor. The p53 protein, encoded by the TP53 tumor suppressor gene that is commonly mutated in CRC, is important in cell cycle arrest needed to repair DNA damage or induce apoptosis to prevent tumor propagation. In this prospective cohort study, we examined CS-associated CRC risks by p53 protein expression level 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). 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 CRC cases diagnosed through 12/31/2002. CS was categorized by smoking status (never, current, former), average number of cigarettes per day (1-19, 20-39, > 40) and cumulative pack-years (1-19, 20-39, > 40). P53 protein expression was determined by immunohistochemistry on tissue microarrays. Tumor cores were scored by combining both staining intensity and percent of cells stained to determine negative, low or high p53 protein expression levels. Multivariate Cox regression models were fit to estimate relative risks (RRs) and 95% confidence intervals (CIs). Results: Of the 732 available CRC cases, 486 (66%) had complete CS and p53 data. Associations between CS and CRC subtypes defined by p53 expression level are shown in the Table. Conclusions: These data demonstrate no clear heterogeneity of CS with CRC subtypes defined by p53 expression levels 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 1676. doi:1538-7445.AM2012-1676

Abstract Background: Colorectal cancer (CRC) is a molecularly heterogeneous disease. Three molecular pathways (traditional, serrated and alternate) have been recently proposed based on integrated combinations of microsatellite instability (MSI), CpG island methylation phenotype (CIMP), BRAF mutation, and KRAS mutation status (Gastroenterol 2010;138:2088-2100). To our knowledge, clinicopathologic associations with these CRC pathways have not been previously described. Methods: Data and tissue resources were obtained from the population-based Iowa Women's Health Study, which recruited 41,836 randomly selected 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 CRC cases diagnosed through 12/31/2002. Established laboratory methods were used to characterize CRC cases by MSI (MSS/MSI-L or MSI-H), CIMP (neg, low, or high), BRAF mutation (wt or mut), and KRAS mutation (wt or mut) status. Molecular pathways were defined as: traditional (MSS/MSI-L, CIMP-neg, BRAF wt, and KRAS wt); serrated (any MSI, CIMP-high, BRAF mut, and KRAS wt), alternate (MSS/MSI-L, CIMP-low, BRAF wt, and KRAS mut), or other pathway. Chi-square tests and analyses of variance were used to compare clinicopathologic features at CRC presentation (age, anatomic subsite, tumor grade, and SEER stage) across the molecular pathways. Results: Comlete and informative MSI, CIMP, BRAF and KRAS data were obtained for 491/732 (67%) CRC cases. Clinicopathologic associations are shown in the Table. Conclusions: These data suggest that distributions of age at diagnosis, subsite, and tumor grade, but not SEER stage, differ across the traditional, serrated, and alternate carcinogenic pathways, which may have implications for molecularly-targeted CRC prevention and/or therapy strategies. 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 5518. doi:1538-7445.AM2012-5518

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