Mutation Enrichment and Transcriptomic Activation Signatures of 419 Molecular Pathways in Cancer

Area of Science:

• Genomics
• Molecular Biology
• Cancer Research

Background:

• Carcinogenesis involves significant alterations in gene regulatory networks.
• Understanding the role of molecular pathways in cancer is crucial for developing targeted therapies.

Purpose of the Study:

• To investigate the involvement of signaling, metabolic, DNA repair, and cytoskeleton pathways in cancer.
• To analyze mutation and gene expression data across multiple cancer types to determine pathway activation and mutation enrichment.

Main Methods:

• Utilized high-throughput mutation and gene expression data from 4910 primary tumor samples.
• Performed RNA sequencing and whole exome sequencing on tumor samples and compared gene expression with 655 normal tissue profiles.
• Calculated mutation enrichment values and activation levels for 444 molecular pathways across thirteen cancer types.

Main Results:

• Pathway activation profiles were consistent across different cancer types.
• No correlation was observed between mutation enrichment and gene/pathway expression changes.
• DNA repair pathways showed positive median cancer-specific activation and the highest mutation enrichment.
• Signaling and cytoskeleton pathways contained the most frequently mutated genes, suggesting initiator roles in carcinogenesis.

Conclusions:

• DNA repair pathways are significantly altered and frequently mutated in cancer.
• Signaling and cytoskeleton pathways may play initiating roles in cancer development, while metabolic and DNA repair pathways may have supporting roles.