An integrated approach to identify causal network modules of complex diseases with application to colorectal cancer

Zhenshu Wen1, Zhi-Ping Liu, Zhengrong Liu

  • 1Key Laboratory of Systems Biology, SIBS-Novo Nordisk Translational Research Centre for PreDiabetes, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China.

Abstract

Insights

This study introduces a new network approach to find causal biomarkers for complex diseases like colorectal cancer (CRC) by integrating multiple data types. The method identifies key gene modules linked to cancer hallmarks, offering potential therapeutic targets.

Area of Science:

  • Bioinformatics
  • Systems Biology
  • Computational Biology

Background:

  • Gene expression data alone struggles to differentiate causative disease genes from effects.
  • Identifying causal relationships between biological networks and disease traits requires integrated approaches.
  • Complex diseases necessitate advanced methods beyond single data types for biomarker discovery.

Purpose of the Study:

  • To develop a novel network-based approach for identifying putative causal module biomarkers.
  • To integrate heterogeneous data including epigenomic, gene expression, and protein-protein interaction networks.
  • To characterize colorectal cancer (CRC) using identified network modules.

Main Methods:

  • Formulated module identification as a mathematical programming problem for efficient and accurate solutions.
  • Integrated epigenomic data, gene expression data, and protein-protein interaction networks.
  • Applied the approach to CRC and validated findings using external datasets and functional enrichment analysis.

Main Results:

  • Identified several network modules as potential biomarkers for CRC characterization.
  • Validated the candidate biomarker properties and method effectiveness across multiple datasets.
  • Found identified modules strongly associated with cancer hallmarks and CRC-specific functions like inflammatory response.

Conclusions:

  • The developed network-based approach effectively identifies causal module biomarkers for complex diseases.
  • Aberrant DNA methylation in transcription factors (TFs) significantly impacts gene activity in CRC.
  • The method shows potential for extension to other complex diseases and multiclassification problems.