Citations

Abstract The 19p13.1 breast cancer susceptibility locus is a modifier of breast cancer risk in BRCA1 mutation carriers and is also associated with the risk of ovarian cancer. Here, we investigated 19p13.1 variation and risk of breast cancer subtypes, defined by estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor-2 (HER2) status, using 48,869 breast cancer cases and 49,787 controls from the Breast Cancer Association Consortium (BCAC). Variants from 19p13.1 were not associated with breast cancer overall or with ER-positive breast cancer but were significantly associated with ER-negative breast cancer risk [rs8170 OR, 1.10; 95% confidence interval (CI), 1.05–1.15; P = 3.49 × 10−5] and triple-negative (ER-, PR-, and HER2-negative) breast cancer (rs8170: OR, 1.22; 95% CI, 1.13–1.31; P = 2.22 × 10−7). However, rs8170 was no longer associated with ER-negative breast cancer risk when triple-negative cases were excluded (OR, 0.98; 95% CI, 0.89–1.07; P = 0.62). In addition, a combined analysis of triple-negative cases from BCAC and the Triple Negative Breast Cancer Consortium (TNBCC; N = 3,566) identified a genome-wide significant association between rs8170 and triple-negative breast cancer risk (OR, 1.25; 95% CI, 1.18–1.33; P = 3.31 × 10−13]. Thus, 19p13.1 is the first triple-negative–specific breast cancer risk locus and the first locus specific to a histologic subtype defined by ER, PR, and HER2 to be identified. These findings provide convincing evidence that genetic susceptibility to breast cancer varies by tumor subtype and that triple-negative tumors and other subtypes likely arise through distinct etiologic pathways. Cancer Res; 72(7); 1795–803. ©2012 AACR.

Abstract Background: Genetic influences may be discerned in families that have multiple affected members and may manifest as an earlier age of cancer diagnosis. In this study, we determine whether cancers develop at an earlier age in multiplex Familial Barrett's Esophagus (FBE) kindreds, defined by 3 or more members affected by Barrett's esophagus (BE) or esophageal adenocarcinoma (EAC). Methods: Information on BE/EAC risk factors and family history was collected from probands at eight tertiary care academic hospitals. Age of cancer diagnosis and other risk factors were compared between nonfamilial (no affected relatives), duplex (two affected relatives), and multiplex (three or more affected relatives) FBE kindreds. Results: The study included 830 nonfamilial, 274 duplex, and 41 multiplex FBE kindreds with 274, 133, and 43 EAC and 566, 288, and 103 BE cases, respectively. Multivariable mixed models adjusting for familial correlations showed that multiplex kindreds were associated with a younger age of cancer diagnosis (P = 0.0186). Median age of cancer diagnosis was significantly younger in multiplex compared with duplex and nonfamilial kindreds (57 vs. 62 vs. 63 years, respectively, P = 0.0448). Mean body mass index was significantly lower in multiplex kindreds (P = 0.0033), as was smoking (P < 0.0001), and reported regurgitation (P = 0.0014). Conclusions: Members of multiplex FBE kindreds develop EAC at an earlier age compared with nonfamilial EAC cases. Multiplex kindreds do not have a higher proportion of common risk factors for EAC, suggesting that this aggregation might be related to a genetic factor. Impact: These findings indicate that efforts to identify susceptibility genes for BE and EAC will need to focus on multiplex kindreds. Cancer Epidemiol Biomarkers Prev; 21(2); 376–83. ©2011 AACR.

Background— Preclinical diastolic dysfunction (PDD) has been broadly defined as subjects with left ventricular diastolic dysfunction, without the diagnosis of congestive heart failure (HF) and with normal systolic function. Our objective was to determine the risk factors associated with the progression from PDD (stage B) HF to symptomatic (stage C) HF. Methods and Results— Using the resources of the Rochester Epidemiology Project, all residents of Olmsted County, MN, who underwent echocardiography between January 1, 2004, and December 31, 2005, and had grade 2–4 diastolic dysfunction and ejection fraction ≥50% were identified. Patients with a diagnosis of HF before or within 30 days of the echocardiogram were excluded. Patients were also excluded if they had a diagnosis of atrial fibrillation or severe mitral or aortic valve regurgitation at the time of the echocardiogram. A total of 388 patients met the inclusion criteria. The mean age of the cohort was 67±12 years, with a female (57%) predominance. Prevalence of renal insufficiency (estimated glomerular filtration rate <60 mL/min per 1.73 m 2 ) was 34%. The 3-year cumulative probabilities of development of (stage C) HF, development of atrial fibrillation, cardiac hospitalization, and mortality were 11.6%, 14.5%, 17.7%, and 10.1% respectively. In multivariable Cox proportional hazard regression analysis, we determined that age, renal dysfunction, and right ventricular systolic pressure were independently associated with the development of HF. Conclusions— This population-based study demonstrated that in PDD (stage B) HF, there was a moderate degree of progression to symptomatic (stage C) HF over 3 years, and renal dysfunction was associated with this progression independent of age, sex, hypertension, coronary disease, and ejection fraction.

Purpose A phase I/II study of cixutumumab (IMC-A12) in children with refractory solid tumors was conducted. This study was designed to assess the toxicities, pharmacokinetics, and pharmacodynamics of cixutumumab in children to determine a recommended phase II dose and to assess antitumor activity in Ewing sarcoma (ES). Patients and Methods Pediatric patients with relapsed or refractory solid tumors were treated with cixutumumab as a 1-hour intravenous infusion once per week. Two dose levels—6 and 9 mg/kg—were evaluated using a standard three-plus-three cohort design. Patients with refractory ES were treated in an expanded phase II cohort at each dose level. Results Forty-seven eligible patients with a median age of 15 years (range, 4 to 28 years) were enrolled. Twelve patients were treated in the dose-finding phase. Hematologic and nonhematologic toxicities were generally mild and infrequent. Dose-limiting toxicities included grade 4 thrombocytopenia at 6 mg/kg and grade 3 dehydration at 9 mg/kg. Mean trough concentration (± standard deviation) at 9 mg/kg was 106 ± 57 μg/mL, which exceeded the effective trough concentration of 60 μg/mL observed in xenograft models. Three patients with ES had confirmed partial responses: one of 10 at 6 mg/kg and two of 20 at 9 mg/kg. Serum insulin-like growth factor I (IGF-I) levels consistently increased after one dose of cixutumumab. Tumor IGF-I receptor expression by immunohistochemistry did not correlate with response in patients with ES. Conclusion Cixutumumab is well tolerated in children with refractory solid tumors. The recommended phase II dose is 9 mg/kg. Limited single-agent activity of cixutumumab was seen in ES.

AbstractOver the past several years, genome‐wide association studies (GWAS) have succeeded in identifying hundreds of genetic markers associated with common diseases. However, most of these markers confer relatively small increments of risk and explain only a small proportion of familial clustering. To identify obstacles to future progress in genetic epidemiology research and provide recommendations to NIH for overcoming these barriers, the National Cancer Institute sponsored a workshop entitled “Next Generation Analytic Tools for Large‐Scale Genetic Epidemiology Studies of Complex Diseases” on September 15–16, 2010. The goal of the workshop was to facilitate discussions on (1) statistical strategies and methods to efficiently identify genetic and environmental factors contributing to the risk of complex disease; and (2) how to develop, apply, and evaluate these strategies for the design, analysis, and interpretation of large‐scale complex disease association studies in order to guide NIH in setting the future agenda in this area of research. The workshop was organized as a series of short presentations covering scientific (gene‐gene and gene‐environment interaction, complex phenotypes, and rare variants and next generation sequencing) and methodological (simulation modeling and computational resources and data management) topic areas. Specific needs to advance the field were identified during each session and are summarized.Genet. Epidemiol. 36 : 22–35, 2012. © 2011 Wiley Periodicals, Inc.

Abstract Background and Aims: Cancer and Leukemia Group B 80303 was a randomized, phase III study in patients with advanced pancreatic cancer treated with gemcitabine plus either bevacizumab or placebo. We prospectively collected germline DNA and conducted a genome-wide association study (GWAS) using overall survival (OS) as the endpoint. Experimental Design: DNA from 351 patients was genotyped for more than 550,000 single-nucleotide polymorphisms (SNP). Associations between OS and SNPs were investigated using the log-linear 2-way multiplicative Cox proportional hazards model. The subset of 294 genetically European patients was used for the primary analysis. Results: A nonsynonymous SNP in interleukin (IL)17F (rs763780, H161R) and an intronic SNP in strong linkage disequilibrium (rs7771466) were associated with OS using genome-wide criteria (P ≤ 10−7). Median OS was significantly shorter (P = 2.61 × 10−8) for the rs763780 heterozygotes [3.1 months; 95% confidence interval (CI), 2.3–4.3] than for the patients without this variant (6.8 months; 95% CI, 5.8–7.3). After adjustment by stratification factors, the P value for the association was 9.51 × 10−7. Conclusions: The variant 161R form of IL-17F is a natural antagonist of the antiangiogenic effects of wild-type 161H IL-17F, and angiogenesis may play an important role in the metastatic spread of pancreatic cancer. In this preliminary study, we hypothesize that the angiogenetic potential of pancreatic cancers in patients with variant IL-17F is higher than that of tumors in patients with wild-type IL-17F, conferring worse prognosis. This exploratory GWAS may provide the foundation for testing the biology and clinical effects of novel genes and their heritable variants through mechanistic and confirmatory studies in pancreatic cancer. Clin Cancer Res; 18(2); 577–84. ©2011 AACR.

Purpose Metastatic melanoma, a highly vascularized tumor with strong expression of vascular endothelial growth factor, has an overall poor prognosis. We conducted a placebo-controlled, double-blind phase II study of carboplatin plus paclitaxel with or without bevacizumab in patients with previously untreated metastatic melanoma. Patients and Methods Patients were randomly assigned in a two-to-one ratio to carboplatin (area under the curve, 5) plus paclitaxel (175 mg/m 2 ) and bevacizumab (15 mg/kg; CPB) or placebo (CP) administered intravenously once every 3 weeks. Progression-free survival (PFS) was the primary end point. Secondary end points included overall survival (OS) and safety. Results Two hundred fourteen patients (73% with M1c disease) were randomly assigned. With a median follow-up of 13 months, median PFS was 4.2 months for the CP arm (n = 71) and 5.6 months for the CPB arm (n = 143; hazard ratio [HR], 0.78; P = .1414). Overall response rates were 16.4% and 25.5%, respectively (P = .1577). With 13-month follow-up, median OS was 8.6 months in the CP arm versus 12.3 months in the CPB arm (HR, 0.67; P = .0366), whereas in an evaluation 4 months later, it was 9.2 versus 12.3 months, respectively (HR, 0.79; P = .1916). In patients with elevated serum lactate dehydrogenase (n = 84), median PFS and OS were longer in the CPB arm (PFS: 4.4 v 2.7 months; HR, 0.62; OS: 8.5 v 7.5 months; HR, 0.52). No new safety signals were observed. Conclusion The study did not meet the primary objective of statistically significant improvement in PFS with the addition of bevacizumab to carboplatin plus paclitaxel. A larger phase III study will be necessary to determine whether there is benefit to the addition of bevacizumab to carboplatin plus paclitaxel in this disease setting.

Fasting results in the mobilization of adipose stores and the elevation of levels of free fatty acids (FFA). In humans, this process is driven by a release in GH. Little is known regarding the role of GH in modulating this process during early stages of fasting in the mouse. Confirmation of the role of GH in modulating FFA release in the fasting mouse is of particular importance given the frequent use of mouse models to study metabolic mechanisms. Here, we correlate the initial release of FFA throughout fasting in mice with pulsatile GH secretion. Observations illustrate the rapid release of FFA in response to food withdrawal. This does not correlate with a rise in GH secretion. Rather, we observed a striking loss in pulsatile secretion of GH throughout the first 6 h of fasting, suggesting that GH does not modulate the initial release of FFA in the mouse in response to fasting. This was confirmed in GH receptor knockout mice, in which we observed a robust fasting-induced rise in FFA. We further illustrate the dynamic relationship between the orexigenic and anorexigenic hormones ghrelin and leptin during fasting in the mouse. Our findings show an initial suppression of leptin and the eventual rise in circulating levels of acyl-ghrelin with fasting. However, altered acyl-ghrelin and leptin secretion occurs well after the rise in FFA and the suppression of GH secretion. Consequently, we conclude that although acyl-ghrelin and leptin may modulate the physiological response to drive food intake, these changes do not contribute to the initial loss of pulsatile GH secretion. Rather, it appears that the suppression of GH secretion in fasting may occur in response to an elevation in fasting levels of FFA or physiological stress. Observations highlight a divergent role for GH in modulating FFA release between man and mouse.