Abstract 817: Mendelian randomization and mediation analysis of 5p15.33, telomere length and lung cancer risk
Notice bibliographique
Résumé
Abstract Background: Telomere length (TL) is a predictor of lung cancer risk, but the direction of this association differs between and prospective and case-control studies. This discrepancy may be attributed to reverse causation in the latter, due to disease-related changes in TL that is measured after diagnosis or treatment. To overcome these limitations and characterize the relationship between TL and lung cancer risk we carried out observational and mediation analyses, and a 2-stage Mendelian Randomization (MR) analysis, where we developed novel genetic instruments for TL and tested the association with lung cancer using 20 OncoArray studies in the Transdisciplinary Research in Cancer of the Lung group of the International Lung Cancer Consortium. Methods: The observational analysis examined TL measured using qPCR in 1128 cases and 928 controls. Odds ratios (OR) for TL were adjusted for age, sex and cigarette pack-years. Mediation analysis was used to estimate the% of the lung cancer association in 5p15 that operates through TL. To develop novel TL instruments, variants identified through deep sequencing of the 5p15 locus were genotyped in 900 controls. Variants that met MR criteria were combined into a single instrumental variable (IV), and its association with TL was estimated. We also used 6 previously identified TL predictors (p<5×10-8) as genetic instruments: rs10165485 (ACYP2), rs10936599 (TERC), rs11100479 (NAF1), rs9420907 (OBFC1), rs6028466 (DHX35), rs755017 (RTEL1). For these SNPs association estimates for TL were obtained from the literature. To estimate the association with lung cancer risk, we tested all 7 IVs using data from 14324 lung cases and 10783 controls in OncoArray. Lastly, to obtain a summary estimate for the causal effect of TL on lung cancer risk, ORs from OncoArray were combined with â-TL estimates using a likelihood-based MR model. Results: The observational analysis suggested that longer TL is associated with decreased lung cancer risk (OR = 0.94, p = 0.04). This was more pronounced for squamous carcinoma (OR = 0.77, p = 1.1×10-4). We also showed that TL mediates up to 8% (p<0.05) of the lung cancer signal in 5p15. In the first stage of the MR analysis, we identified 8 5p15 SNPs that were associated with TL (p<5×10-3), including 6 novel rare variants, not previously associated with TL. Together these variants were reliably associated with TL (â = 0.15, p = 1.8×10-7) and explained 2.3% of variance in TL. Using this new instrument and 6 other SNPs as IVs, our MR analysis showed that longer TL is a risk factor for lung cancer (OR = 1.77, 95% CI: 1.32-1.54), especially adenocarcinoma (OR = 2.02, 95% CI: 1.29-3.71). Conclusions: We developed novel genetic instruments for TL, and confirmed that genetically predicted longer TL is associated with increased lung cancer risk. These findings suggest that previously reported associations of long TL with decreased risk were likely due to residual confounding by smoking, age and/or reverse causation. Citation Format: Linda Kachuri, George Davey Smith, Geoffrey Liu, Maria Teresa Landi, David C. Christiani, Neil E. Caporaso, James D. McKay, Xifeng Wu, Melinda C. Aldrich, Gad Rennert, Dawn Teare, Chu Chen, Gary E. Goodman, Jennifer A. Doherty, John K. Field, Lambertus A. Kiemeney, Adonina Tardón, Aage Haugen, Stephen Lam, Loic Le Marchand, Matthew B. Schabath, Angeline S. Andrew, Mattias Johansson, Jonas Manjer, Philip Lazarus, Susanne Arnold, Gordon Fehringer, Xuchen Zong, Paul Brennan, Stig E. Bojesen, Christopher I. Amos, Rayjean J. Hung. Mendelian randomization and mediation analysis of 5p15.33, telomere length and lung cancer risk. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 817.
Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.
Comment cette classification a été obtenuedéplier
Prédiction machine sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Le volet Gemma est une étiquette directe du modèle pour chaque travail de la base, lue sur la notice réduite au titre. Le volet Codex est un classifieur appris des 10 348 étiquettes directes de Codex et calibré sur les taux pondérés de l'échantillon; les champs sans appui suffisant ne portent aucun appel Codex. Le mode candidate est l'union des deux volets; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont pas des étiquettes humaines.
Scores du classifieur distillé par catégorie (deux têtes)
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,031 | 0,054 |
| Méta-épidémiologie (sens strict) | 0,001 | 0,000 |
| Méta-épidémiologie (sens large) | 0,001 | 0,003 |
| Bibliométrie | 0,001 | 0,001 |
| Études des sciences et des technologies | 0,001 | 0,001 |
| Communication savante | 0,001 | 0,001 |
| Science ouverte | 0,002 | 0,001 |
| Intégrité de la recherche | 0,001 | 0,001 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,010 | 0,000 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule source (Gemma direct ou Codex distillé), pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».