Dataset Information

Integrative mixture of experts to combine clinical factors and gene markers.

ABSTRACT:

Motivation

Microarrays are being increasingly used in cancer research to better characterize and classify tumors by selecting marker genes. However, as very few of these genes have been validated as predictive biomarkers so far, it is mostly conventional clinical and pathological factors that are being used as prognostic indicators of clinical course. Combining clinical data with gene expression data may add valuable information, but it is a challenging task due to their categorical versus continuous characteristics. We have further developed the mixture of experts (ME) methodology, a promising approach to tackle complex non-linear problems. Several variants are proposed in integrative ME as well as the inclusion of various gene selection methods to select a hybrid signature.

Results

We show on three cancer studies that prediction accuracy can be improved when combining both types of variables. Furthermore, the selected genes were found to be of high relevance and can be considered as potential biomarkers for the prognostic selection of cancer therapy.

Availability

Integrative ME is implemented in the R package integrativeME (http://cran.r-project.org/).

SUBMITTER: Le Cao KA

PROVIDER: S-EPMC2859127 | biostudies-literature | 2010 May

REPOSITORIES: biostudies-literature

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Publications

Integrative mixture of experts to combine clinical factors and gene markers.

Lê Cao Kim-Anh KA Meugnier Emmanuelle E McLachlan Geoffrey J GJ

Bioinformatics (Oxford, England) 20100311 9

<h4>Motivation</h4>Microarrays are being increasingly used in cancer research to better characterize and classify tumors by selecting marker genes. However, as very few of these genes have been validated as predictive biomarkers so far, it is mostly conventional clinical and pathological factors that are being used as prognostic indicators of clinical course. Combining clinical data with gene expression data may add valuable information, but it is a challenging task due to their categorical vers ...[more]

PMID: 20223834

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Dataset Information

Integrative mixture of experts to combine clinical factors and gene markers.

Motivation

Results

Availability

Publications

Integrative mixture of experts to combine clinical factors and gene markers.

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