Short tandem repeat mutations regulate gene expression in colorectal cancer

Area of Science:

• Genomics
• Cancer Biology
• Molecular Genetics

Background:

• Short tandem repeat (STR) mutations are common in colorectal cancer (CRC), especially in microsatellite instability (MSI) tumors.
• The impact of STR mutations on gene regulation in CRC is not well understood.

Purpose of the Study:

• To investigate the gene regulatory effects of STR mutations in CRC by integrating mutation, clinical, and gene expression data.
• To identify specific STRs that influence gene expression in CRC.

Main Methods:

• Integrated analysis of STR mutation data, clinical information, and gene expression profiles from CRC tumors.
• Statistical modeling to identify associations between STR length variation and gene expression levels.
• Validation of STR-gene expression relationships using linear models.

Main Results:

• STR mutability in CRC is influenced by MSI status, repeat unit size, and repeat length.
• Identified 1244 putative expression STRs (eSTRs) associated with gene expression in CRC.
• Found 73 eSTRs linked to cancer-related genes, including nine CRC-specific genes, with increased mutability in MSI tumors.

Conclusions:

• STR length variations play a significant role in regulating gene expression in colorectal cancer.
• eSTRs represent a novel mechanism by which CRC tumors can alter their phenotype.
• These findings suggest potential for new STR-based therapeutic strategies in cancer treatment.