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Published on: March 31, 2022
Small-molecule-induced DNA damage identifies alternative DNA structures in human genes
Raphaël Rodriguez1, Kyle M Miller, Josep V Forment
1Department of Chemistry, University of Cambridge, Cambridge, UK.
Nature Chemical Biology
|February 7, 2012
Summary
The drug pyridostatin halts cancer cell growth by causing DNA damage, particularly in genes with G-quadruplex structures. This impacts gene expression, including the SRC proto-oncogene, reducing cancer cell motility.
Area of Science:
- Genomics
- Molecular Biology
- Cancer Research
Background:
- Guanine-rich DNA sequences form non-Watson-Crick structures like G-quadruplexes.
- The in vivo existence and function of these structures in mammalian cells remain under investigation.
Purpose of the Study:
- To investigate the mechanism by which the G-quadruplex-interacting drug pyridostatin affects cancer cells.
- To identify the genomic targets of pyridostatin and its impact on gene expression.
Main Methods:
- Chromatin immunoprecipitation sequencing (ChIP-seq) to map DNA damage sites (γH2AX).
- Analysis of pyridostatin's effect on gene expression and protein abundance.
- Assessment of SRC-dependent cellular motility in breast cancer cells.
Main Results:
- Pyridostatin induces replication- and transcription-dependent DNA damage in human cancer cells.
- Pyridostatin targets gene bodies with G-quadruplex-forming sequence potential.
- Pyridostatin downregulates the proto-oncogene SRC and reduces SRC-mediated cancer cell motility.
Conclusions:
- Pyridostatin's anti-cancer effects are mediated by inducing DNA damage at G-quadruplex-rich genomic regions.
- This study validates SRC as a therapeutic target for pyridostatin in cancer.
- An unbiased genomic approach can uncover functional DNA-drug interactions.
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