Core promoter mutation contributes to abnormal gene expression in bladder cancer

Area of Science:

• Genomics
• Cancer Biology
• Molecular Oncology

Background:

• Bladder cancer is a highly mortal disease with a distinct gene expression signature.
• Altered gene expression is implicated in bladder cancer etiology, but the underlying mechanisms remain unclear.
• Core promoters regulate transcriptional initiation, suggesting their mutations could drive altered gene expression.

Purpose of the Study:

• To investigate the role of core promoter mutations in bladder cancer.
• To identify recurrent somatic and germline mutations in core promoters of bladder cancer genes.
• To understand how core promoter mutations affect gene expression and contribute to bladder cancer development.

Main Methods:

• Genome-wide characterization of core promoter mutations in 77 Spanish bladder cancer cases.
• RNA-sequencing (RNA-seq) to analyze gene expression in bladder cancer.
• Luciferase reporter gene assays to validate the functional impact of core promoter mutations.

Main Results:

• Identified 69 recurrent somatic mutations in 61 core promoters (62 genes) and 28 recurrent germline mutations in 20 core promoters (21 genes).
• Mutations were found in TERT, oncogenes, and tumor suppressors, including genes with known roles in bladder cancer.
• Observed altered expression of core promoter-mutated genes and validated their functional effects on gene expression.
• Identified potential drug targets for core promoter-mutated genes.

Conclusions:

• Core promoter mutations are a significant factor in bladder cancer development.
• These mutations contribute to bladder cancer by altering the expression of critical genes.
• The findings highlight a novel mechanism in bladder cancer pathogenesis and suggest therapeutic strategies.