Genetic Determinants of Lung Cancer Prognosis in Never Smokers: A Pooled Analysis in the International Lung Cancer Consortium
CANCER EPIDEMIOLOGY BIOMARKERS & PREVENTION
Authors: Brhane, Yonathan; Yang, Ping; Christiani, David C.; Liu, Geoffrey; McLaughlin, John R.; Brennan, Paul; Shete, Sanjay; Field, John K.; Tardon, Adonina; Kohno, Takashi; Shiraishi, Kouya; Matsuo, Keitaro; Bosse, Yohan; Amos, Christopher, I; Hung, Rayjean J.
Abstract
Background: Lung cancer remains the leading cause of cancer death worldwide, with 15% to 20% occurring in never smokers. To assess genetic determinants for prognosis among never smokers, we conducted a genome-wide investigation in the International Lung Cancer Consortium (ILCCO). Methods: Genomic and clinical data from 1,569 never-smoking patients with lung cancer of European ancestry from 10 ILCCO studies were included. HRs and 95% confidence intervals of overall survival were estimated. We assessed whether the associations were mediated through mRNA expression-based 1,553 normal lung tissues from the lung expression quantitative trait loci (eQTL) dataset and Genotype-Tissue Expression (GTEx). For cross-ethnicity generalization, we assessed the associations in a Japanese study (N = 887). Results: One locus at 13q22.2 was associated with lung adenocarcinoma survival at genome-wide level, with carriers of rs12875562-T allele exhibiting poor prognosis [HR = 1.71 (1.41-2.07), P = 3.60 x 10(-8)], and altered mRNA expression of LMO7DN in lung tissue (GTEx, P = 9.40 x 10(-7); Lung eQTL dataset, P = 0.003). Furthermore, 2 of 11 independent loci that reached the suggestive significance level (P < 10(-6)) were significant eQTL affecting mRNA expression of nearby genes in lung tissues, including CAPZB at 1p36.13 and UBAC1 at 9q34.3. One locus encoding NWD2/KIAA1239 at 4p14 showed associations in both European [HR = 0.50 (0.38-0.66), P = 6.92 x 10(-7)] and Japanese populations [HR = 0.79 (0.67-0.94), P = 0.007]. Conclusions: Based on the largest genomic investigation on the lung cancer prognosis of never smokers to date, we observed that lung cancer prognosis is affected by inherited genetic variants. Impact: We identified one locus near LMO7DN at genome-wide level and several potential prognostic genes with cis-effect on mRNA expression. Further functional genomics work is required to understand their role in tumor progression.
Genome-wide Association Study Identifies Four Genetic Loci Associated with Thyroid Volume and Goiter Risk
AMERICAN JOURNAL OF HUMAN GENETICS
Authors: Teumer, Alexander; Rawal, Rajesh; Homuth, Georg; Ernst, Florian; Heier, Margit; Evert, Matthias; Dombrowski, Frank; Voelker, Uwe; Nauck, Matthias; Radke, Doerte; Ittermann, Till; Biffar, Reiner; Doering, Angela; Gieger, Christian; Klopp, Norman; Wichmann, H. -Erich; Wallaschofski, Henri; Meisinger, Christa; Voelzke, Henry
Abstract
Thyroid disorders such as goiters represent important diseases, especially in iodine-deficient areas. Sibling studies have demonstrated that genetic factors substantially contribute to the interindividual variation of thyroid volume. We performed a genome-wide association study of this phenotype by analyzing a discovery cohort consisting of 3620 participants of the Study of Health in Pomerania (SHIP). Four genetic loci were associated with thyroid volume on a genome-wide level of significance. Of these, two independent loci are located upstream of and within CAPZB, which encodes the beta subunit of the barbed-end F-actin binding protein that modulates actin polymerization, a process crucial in the colloid engulfment during thyroglobulin mobilization in the thyroid. The third locus marks FGF7, which encodes fibroblast growth factor 7. Members of this protein family have been discussed as putative signal molecules involved in the regulation of thyroid development. The fourth locus represents a "gene desert" on chromosome 16q23, located directly downstream of the predicted coding sequence LOC440389, which, however, had already been removed from the NCBI database as a result of the standard genome annotation processing at the time that this study was initiated. Experimental proof of the formerly predicted mature mRNA, however, demonstrates that LOC440389 indeed represents a real gene. All four associations were replicated in an independent sample of 1290 participants of the KORA study. These results increase the knowledge about genetic factors and physiological mechanisms influencing thyroid volume.