VarWalker: personalized mutation network analysis of putative cancer genes from next-generation sequencing data

Peilin Jia1, Zhongming Zhao2

  • 1Department of Biomedical Informatics, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America ; Center for Quantitative Sciences, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America.

Plos Computational Biology
|February 12, 2014
PubMed

Insights

Identifying cancer driver mutations is crucial for drug discovery. VarWalker, a novel network method, effectively prioritizes infrequently mutated driver genes by analyzing interactions, improving upon single-gene approaches.

Area of Science:

  • Genomics
  • Bioinformatics
  • Cancer Research

Background:

  • Interpreting next-generation sequencing (NGS) mutation data requires distinguishing driver from passenger mutations.
  • Current methods focusing on single-gene frequencies miss infrequently mutated driver genes and ignore gene interactions.
  • Identifying driver mutations is key for targeted therapies and new drug development.

Purpose of the Study:

  • To introduce VarWalker, a novel mutation network method for prioritizing driver genes in large-scale cancer mutation data.
  • To overcome limitations of single-gene frequency approaches by incorporating functional gene interconnections.
  • To enhance the identification of targetable genes and potential new cancer drugs.

Main Methods:

  • VarWalker utilizes generalized additive models based on sample-specific mutation profiles.
  • It builds on joint frequencies of mutated genes and their interactors identified via Random Walk with Restart in protein-protein interaction networks.
  • The method was applied to lung adenocarcinoma and melanoma datasets (>300 tumor genomes).

Main Results:

  • VarWalker successfully prioritized well-known, infrequently mutated driver genes by considering their interactions with recurrently mutated genes.
  • Consensus mutation subnetworks enriched with cancer genes and pathways were derived for specific cancer types.
  • Network-assisted approaches demonstrated effectiveness in detecting cancer driver genes in NGS data.

Conclusions:

  • VarWalker offers a powerful network-based approach to identify cancer driver genes from NGS data.
  • This method improves upon conventional single-gene analyses by capturing crucial gene network information.
  • VarWalker facilitates the discovery of novel, infrequently mutated driver genes for therapeutic targeting.

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