Identifying common prognostic factors in genomic cancer studies: A novel index for censored outcomes

<p>Abstract</p> <p>Background</p> <p>With the growing number of public repositories for high-throughput genomic data, it is of great interest to combine the results produced by independent research groups. Such a combination allows the identification of common genomic f...

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Main Authors: Moreau Thierry, Rouam Sigrid, Broët Philippe
Format: Article
Language:English
Published: BMC 2010-03-01
Series:BMC Bioinformatics
Online Access:http://www.biomedcentral.com/1471-2105/11/150
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author Moreau Thierry
Rouam Sigrid
Broët Philippe
author_facet Moreau Thierry
Rouam Sigrid
Broët Philippe
author_sort Moreau Thierry
collection DOAJ
description <p>Abstract</p> <p>Background</p> <p>With the growing number of public repositories for high-throughput genomic data, it is of great interest to combine the results produced by independent research groups. Such a combination allows the identification of common genomic factors across multiple cancer types and provides new insights into the disease process. In the framework of the proportional hazards model, classical procedures, which consist of ranking genes according to the estimated hazard ratio or the p-value obtained from a test statistic of no association between survival and gene expression level, are not suitable for gene selection across multiple genomic datasets with different sample sizes. We propose a novel index for identifying genes with a common effect across heterogeneous genomic studies designed to remain stable whatever the sample size and which has a straightforward interpretation in terms of the percentage of separability between patients according to their survival times and gene expression measurements.</p> <p>Results</p> <p>The simulations results show that the proposed index is not substantially affected by the sample size of the study and the censoring. They also show that its separability performance is higher than indices of predictive accuracy relying on the likelihood function. A simulated example illustrates the good operating characteristics of our index. In addition, we demonstrate that it is linked to the score statistic and possesses a biologically relevant interpretation.</p> <p>The practical use of the index is illustrated for identifying genes with common effects across eight independent genomic cancer studies of different sample sizes. The meta-selection allows the identification of four genes (<it>ESPL1</it>, <it>KIF4A</it>, <it>HJURP</it>, <it>LRIG1</it>) that are biologically relevant to the carcinogenesis process and have a prognostic impact on survival outcome across various solid tumors.</p> <p>Conclusion</p> <p>The proposed index is a promising tool for identifying factors having a prognostic impact across a collection of heterogeneous genomic datasets of various sizes.</p>
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spelling doaj.art-8f0b7a1195b44d3187b187186488e77e2022-12-22T03:29:21ZengBMCBMC Bioinformatics1471-21052010-03-0111115010.1186/1471-2105-11-150Identifying common prognostic factors in genomic cancer studies: A novel index for censored outcomesMoreau ThierryRouam SigridBroët Philippe<p>Abstract</p> <p>Background</p> <p>With the growing number of public repositories for high-throughput genomic data, it is of great interest to combine the results produced by independent research groups. Such a combination allows the identification of common genomic factors across multiple cancer types and provides new insights into the disease process. In the framework of the proportional hazards model, classical procedures, which consist of ranking genes according to the estimated hazard ratio or the p-value obtained from a test statistic of no association between survival and gene expression level, are not suitable for gene selection across multiple genomic datasets with different sample sizes. We propose a novel index for identifying genes with a common effect across heterogeneous genomic studies designed to remain stable whatever the sample size and which has a straightforward interpretation in terms of the percentage of separability between patients according to their survival times and gene expression measurements.</p> <p>Results</p> <p>The simulations results show that the proposed index is not substantially affected by the sample size of the study and the censoring. They also show that its separability performance is higher than indices of predictive accuracy relying on the likelihood function. A simulated example illustrates the good operating characteristics of our index. In addition, we demonstrate that it is linked to the score statistic and possesses a biologically relevant interpretation.</p> <p>The practical use of the index is illustrated for identifying genes with common effects across eight independent genomic cancer studies of different sample sizes. The meta-selection allows the identification of four genes (<it>ESPL1</it>, <it>KIF4A</it>, <it>HJURP</it>, <it>LRIG1</it>) that are biologically relevant to the carcinogenesis process and have a prognostic impact on survival outcome across various solid tumors.</p> <p>Conclusion</p> <p>The proposed index is a promising tool for identifying factors having a prognostic impact across a collection of heterogeneous genomic datasets of various sizes.</p>http://www.biomedcentral.com/1471-2105/11/150
spellingShingle Moreau Thierry
Rouam Sigrid
Broët Philippe
Identifying common prognostic factors in genomic cancer studies: A novel index for censored outcomes
BMC Bioinformatics
title Identifying common prognostic factors in genomic cancer studies: A novel index for censored outcomes
title_full Identifying common prognostic factors in genomic cancer studies: A novel index for censored outcomes
title_fullStr Identifying common prognostic factors in genomic cancer studies: A novel index for censored outcomes
title_full_unstemmed Identifying common prognostic factors in genomic cancer studies: A novel index for censored outcomes
title_short Identifying common prognostic factors in genomic cancer studies: A novel index for censored outcomes
title_sort identifying common prognostic factors in genomic cancer studies a novel index for censored outcomes
url http://www.biomedcentral.com/1471-2105/11/150
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AT rouamsigrid identifyingcommonprognosticfactorsingenomiccancerstudiesanovelindexforcensoredoutcomes
AT broetphilippe identifyingcommonprognosticfactorsingenomiccancerstudiesanovelindexforcensoredoutcomes