In Vitro Insertional Mutagenesis Screen Identifies Novel Genes Driving Breast Cancer Metastasis

Area of Science:

• Oncology
• Molecular Biology
• Genetics

Background:

• Metastasis is a major cause of cancer mortality, yet the underlying mechanisms and driving genes remain incompletely understood.
• Effective treatments for metastatic cancer are limited, highlighting the urgent need to identify novel metastasis-promoting genes.

Purpose of the Study:

• To identify novel driver genes involved in cancer metastasis.
• To functionally validate candidate genes in experimental metastasis models.
• To establish the clinical relevance of identified genes in breast cancer metastasis.

Main Methods:

• Conducted an in vitro Sleeping Beauty transposon-based forward genetic screen in nonmetastatic SKBR3 human breast cancer cells.
• Utilized Boyden chamber-based matrix invasion assays to select for cells with a de novo invasive phenotype.
• Performed targeted RNA sequencing and gene-centric candidate gene prediction on invasive cell pools.

Main Results:

• Identified both established and novel genes associated with driving metastasis.
• Demonstrated the association of identified genes with metastasis-related processes.
• Confirmed the clinical relevance of these genes in metastatic breast cancer.
• Functionally validated G protein-coupled receptor kinase interacting ArfGAP 2 (GIT2) and muscle-associated receptor tyrosine kinase (MUSK) as metastasis driver genes.

Conclusions:

• The study successfully identified novel metastasis driver genes, including GIT2 and MUSK.
• The developed screening and prediction approach is robust, scalable, and valuable for discovering metastasis-driving genes.
• Findings contribute to a better understanding of cancer metastasis mechanisms and may inform future therapeutic strategies.