A novel high-throughput screening system identifies a small molecule repressive for matrix metalloproteinase-9...

Area of Science:

• Molecular Biology
• Cancer Research
• Drug Discovery

Background:

• Aberrant gene expression drives cancer progression and is a key target for therapeutic intervention.
• Existing bioluminescence reporter systems for high-throughput screening are often hindered by epigenetic silencing of reporter genes.

Purpose of the Study:

• To develop a novel system for stable reporter gene expression in high-throughput screening for cancer drug discovery.
• To identify small molecules that repress matrix metalloproteinase-9 (MMP-9) gene expression.

Main Methods:

• A novel system was created using Flp-mediated homologous recombination to integrate promoter-reporter constructs into open chromosomal locations, preventing epigenetic silencing.
• Over 8000 compounds from the DIVERSet chemical library were screened for repressors of the MMP-9 promoter.
• Mechanistic studies were performed to elucidate the mode of action of identified compounds.

Main Results:

• The novel system successfully overcame reporter gene silencing, enabling a high-throughput screen of over 8000 compounds.
• 5-methyl-2-(4-methylphenyl)-1H-benzimidazole (MPBD) was identified as an inhibitor of MMP-9 gene expression.
• MPBD demonstrated inhibitory effects on MMP-9-dependent oral cancer cell invasion, preosteoclast migration, and osteoclast activity by antagonizing AP-1 function.

Conclusions:

• The Flp-mediated homologous recombination system provides a robust strategy for stable reporter gene integration, overcoming silencing issues in drug discovery.
• This system facilitates the development of high-throughput screening platforms for identifying lead compounds targeting aberrant gene expression in cancer.
• MPBD represents a promising lead compound for targeting MMP-9 in cancer therapies.